Introduce PowerDisplay

Directory.Packages.props

@@ -85,6 +85,7 @@
     <PackageVersion Include="StyleCop.Analyzers" Version="1.2.0-beta.556" />
     <!-- Package System.CodeDom added as a hack for being able to exclude the runtime assets so they don't conflict with 8.0.1. This is a dependency of System.Management but the 8.0.1 version wasn't published to nuget. -->
     <PackageVersion Include="System.CodeDom" Version="9.0.8" />
+    <PackageVersion Include="System.Collections.Immutable" Version="9.0.0" />
     <PackageVersion Include="System.CommandLine" Version="2.0.0-beta4.22272.1" />
     <PackageVersion Include="System.ComponentModel.Composition" Version="9.0.8" />
     <PackageVersion Include="System.Configuration.ConfigurationManager" Version="9.0.8" />
@@ -111,6 +112,7 @@
     <PackageVersion Include="UnitsNet" Version="5.56.0" />
     <PackageVersion Include="UTF.Unknown" Version="2.6.0" />
     <PackageVersion Include="WinUIEx" Version="2.8.0" />
+    <PackageVersion Include="WmiLight" Version="6.14.0" />
     <PackageVersion Include="WPF-UI" Version="3.0.5" />
     <PackageVersion Include="WyHash" Version="1.0.5" />
     <PackageVersion Include="WixToolset.Heat" Version="5.0.2" />

PowerToys.sln

@@ -517,6 +517,8 @@ Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "RegistryPreviewExt", "src\m
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "RegistryPreview", "RegistryPreview", "{929C1324-22E8-4412-A9A8-80E85F3985A5}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "PowerDisplay", "PowerDisplay", "{B5E6F789-0123-4567-8901-23456789ABCD}"
+EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FilePreviewCommon", "src\common\FilePreviewCommon\FilePreviewCommon.csproj", "{9EBAA524-0EDA-470B-95D4-39383285CBB2}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.PowerToys.Run.Plugin.PowerToys", "src\modules\launcher\Plugins\Microsoft.PowerToys.Run.Plugin.PowerToys\Microsoft.PowerToys.Run.Plugin.PowerToys.csproj", "{500DED3E-CFB5-4ED5-ACC6-02B3D6DC336D}"
@@ -563,6 +565,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Hosts", "src\modules\Hosts\
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "RegistryPreview", "src\modules\registrypreview\RegistryPreview\RegistryPreview.csproj", "{8E23E173-7127-4A5F-9F93-3049F2B68047}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "PowerDisplay", "src\modules\powerdisplay\PowerDisplay\PowerDisplay.csproj", "{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}"
+EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "PowerDisplayModuleInterface", "src\modules\powerdisplay\PowerDisplayModuleInterface\PowerDisplayModuleInterface.vcxproj", "{D1234567-8901-2345-6789-ABCDEF012345}"
+EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "EnvironmentVariables", "src\modules\EnvironmentVariables\EnvironmentVariables\EnvironmentVariables.csproj", "{DFF88D16-D36F-40A4-A955-CDCAA76EF7B8}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "FancyZonesEditorCommon", "src\modules\fancyzones\FancyZonesEditorCommon\FancyZonesEditorCommon.csproj", "{C0974915-8A1D-4BF0-977B-9587D3807AB7}"
@@ -2246,6 +2252,22 @@ Global
 		{8E23E173-7127-4A5F-9F93-3049F2B68047}.Release|ARM64.Build.0 = Release|ARM64
 		{8E23E173-7127-4A5F-9F93-3049F2B68047}.Release|x64.ActiveCfg = Release|x64
 		{8E23E173-7127-4A5F-9F93-3049F2B68047}.Release|x64.Build.0 = Release|x64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Debug|ARM64.Build.0 = Debug|ARM64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Debug|x64.ActiveCfg = Debug|x64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Debug|x64.Build.0 = Debug|x64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Release|ARM64.ActiveCfg = Release|ARM64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Release|ARM64.Build.0 = Release|ARM64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Release|x64.ActiveCfg = Release|x64
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF}.Release|x64.Build.0 = Release|x64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Debug|ARM64.Build.0 = Debug|ARM64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Debug|x64.ActiveCfg = Debug|x64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Debug|x64.Build.0 = Debug|x64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Release|ARM64.ActiveCfg = Release|ARM64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Release|ARM64.Build.0 = Release|ARM64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Release|x64.ActiveCfg = Release|x64
+		{D1234567-8901-2345-6789-ABCDEF012345}.Release|x64.Build.0 = Release|x64
 		{DFF88D16-D36F-40A4-A955-CDCAA76EF7B8}.Debug|ARM64.ActiveCfg = Debug|ARM64
 		{DFF88D16-D36F-40A4-A955-CDCAA76EF7B8}.Debug|ARM64.Build.0 = Debug|ARM64
 		{DFF88D16-D36F-40A4-A955-CDCAA76EF7B8}.Debug|x64.ActiveCfg = Debug|x64
@@ -3222,6 +3244,9 @@ Global
 		{C32D254F-7597-4CBE-BF74-D922D81CDF29} = {9873BA05-4C41-4819-9283-CF45D795431B}
 		{02DD46D3-F761-47D9-8894-2D6DA0124650} = {F05E590D-AD46-42BE-9C25-6A63ADD2E3EA}
 		{8E23E173-7127-4A5F-9F93-3049F2B68047} = {929C1324-22E8-4412-A9A8-80E85F3985A5}
+		{A1B2C3D4-E5F6-7890-1234-567890ABCDEF} = {B5E6F789-0123-4567-8901-23456789ABCD}
+		{D1234567-8901-2345-6789-ABCDEF012345} = {B5E6F789-0123-4567-8901-23456789ABCD}
+		{B5E6F789-0123-4567-8901-23456789ABCD} = {4574FDD0-F61D-4376-98BF-E5A1262C11EC}
 		{DFF88D16-D36F-40A4-A955-CDCAA76EF7B8} = {538ED0BB-B863-4B20-98CC-BCDF7FA0B68A}
 		{C0974915-8A1D-4BF0-977B-9587D3807AB7} = {D1D6BC88-09AE-4FB4-AD24-5DED46A791DD}
 		{1D6893CB-BC0C-46A8-A76C-9728706CA51A} = {557C4636-D7E1-4838-A504-7D19B725EE95}

installer/PowerToysSetup/PowerDisplay.wxs

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi"
+     xmlns:util="http://schemas.microsoft.com/wix/UtilExtension" >
+
+  <?include $(sys.CURRENTDIR)\Common.wxi?>
+
+  <?define PowerDisplayAssetsFiles=?>
+  <?define PowerDisplayAssetsFilesPath=$(var.BinDir)WinUI3Apps\Assets\PowerDisplay?>
+
+  <Fragment>
+    <!-- Power Display -->
+    <DirectoryRef Id="WinUI3AppsAssetsFolder">
+      <Directory Id="PowerDisplayAssetsInstallFolder" Name="PowerDisplay" />
+    </DirectoryRef>
+    <DirectoryRef Id="PowerDisplayAssetsInstallFolder" FileSource="$(var.PowerDisplayAssetsFilesPath)">
+    <!-- Generated by generateFileComponents.ps1 -->
+    <!--PowerDisplayAssetsFiles_Component_Def-->
+    </DirectoryRef>
+
+    <ComponentGroup Id="PowerDisplayComponentGroup">
+      <Component Id="RemovePowerDisplayFolder" Guid="B8F2E3A5-72C1-4A2D-9B3F-8E5D7C6A4F9B" Directory="PowerDisplayAssetsInstallFolder" >
+        <RegistryKey Root="$(var.RegistryScope)" Key="Software\Classes\powertoys\components">
+          <RegistryValue Type="string" Name="RemovePowerDisplayFolder" Value="" KeyPath="yes"/>
+        </RegistryKey>
+        <RemoveFolder Id="RemoveFolderPowerDisplayAssetsFolder" Directory="PowerDisplayAssetsInstallFolder" On="uninstall"/>
+      </Component>
+    </ComponentGroup>
+
+  </Fragment>
+</Wix>

installer/PowerToysSetupVNext/PowerDisplay.wxs

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi"
+     xmlns:util="http://schemas.microsoft.com/wix/UtilExtension" >
+
+  <?include $(sys.CURRENTDIR)\Common.wxi?>
+
+  <?define PowerDisplayAssetsFiles=?>
+  <?define PowerDisplayAssetsFilesPath=$(var.BinDir)WinUI3Apps\Assets\PowerDisplay?>
+
+  <Fragment>
+    <!-- Power Display -->
+    <DirectoryRef Id="WinUI3AppsAssetsFolder">
+      <Directory Id="PowerDisplayAssetsInstallFolder" Name="PowerDisplay" />
+    </DirectoryRef>
+    <DirectoryRef Id="PowerDisplayAssetsInstallFolder" FileSource="$(var.PowerDisplayAssetsFilesPath)">
+    <!-- Generated by generateFileComponents.ps1 -->
+    <!--PowerDisplayAssetsFiles_Component_Def-->
+    </DirectoryRef>
+
+    <ComponentGroup Id="PowerDisplayComponentGroup">
+      <Component Id="RemovePowerDisplayFolder" Guid="B8F2E3A5-72C1-4A2D-9B3F-8E5D7C6A4F9B" Directory="PowerDisplayAssetsInstallFolder" >
+        <RegistryKey Root="$(var.RegistryScope)" Key="Software\Classes\powertoys\components">
+          <RegistryValue Type="string" Name="RemovePowerDisplayFolder" Value="" KeyPath="yes"/>
+        </RegistryKey>
+        <RemoveFolder Id="RemoveFolderPowerDisplayAssetsFolder" Directory="PowerDisplayAssetsInstallFolder" On="uninstall"/>
+      </Component>
+    </ComponentGroup>
+
+  </Fragment>
+</Wix>

installer/PowerToysSetupVNext/Product.wxs

@@ -53,6 +53,7 @@
       <ComponentGroupRef Id="LightSwitchComponentGroup" />
       <ComponentGroupRef Id="PeekComponentGroup" />
       <ComponentGroupRef Id="PowerRenameComponentGroup" />
+      <ComponentGroupRef Id="PowerDisplayComponentGroup" />
       <ComponentGroupRef Id="RegistryPreviewComponentGroup" />
       <ComponentGroupRef Id="RunComponentGroup" />
       <ComponentGroupRef Id="SettingsComponentGroup" />

src/common/Common.UI/SettingsDeepLink.cs

@@ -43,6 +43,7 @@ namespace Common.UI
             NewPlus,
             CmdPal,
             ZoomIt,
+            PowerDisplay,
         }
 
         private static string SettingsWindowNameToString(SettingsWindow value)
@@ -113,6 +114,8 @@ namespace Common.UI
                     return "CmdPal";
                 case SettingsWindow.ZoomIt:
                     return "ZoomIt";
+                case SettingsWindow.PowerDisplay:
+                    return "PowerDisplay";
                 default:
                     {
                         return string.Empty;

src/common/ManagedCommon/ModuleType.cs

@@ -29,6 +29,7 @@ namespace ManagedCommon
         PowerRename,
         PowerLauncher,
         PowerAccent,
+        PowerDisplay,
         RegistryPreview,
         MeasureTool,
         ShortcutGuide,

src/common/interop/Constants.cpp

@@ -195,4 +195,12 @@ namespace winrt::PowerToys::Interop::implementation
     {
         return CommonSharedConstants::CMDPAL_SHOW_EVENT;
     }
+    hstring Constants::ShowPowerDisplayEvent()
+    {
+        return CommonSharedConstants::SHOW_POWER_DISPLAY_EVENT;
+    }
+    hstring Constants::TerminatePowerDisplayEvent()
+    {
+        return CommonSharedConstants::TERMINATE_POWER_DISPLAY_EVENT;
+    }
 }

src/common/interop/Constants.h

@@ -52,6 +52,8 @@ namespace winrt::PowerToys::Interop::implementation
         static hstring WorkspacesHotkeyEvent();
         static hstring PowerToysRunnerTerminateSettingsEvent();
         static hstring ShowCmdPalEvent();
+        static hstring ShowPowerDisplayEvent();
+        static hstring TerminatePowerDisplayEvent();
     };
 }
 

src/common/interop/shared_constants.h

@@ -131,6 +131,10 @@ namespace CommonSharedConstants
     const wchar_t ZOOMIT_REFRESH_SETTINGS_EVENT[] = L"Local\\PowerToysZoomIt-RefreshSettingsEvent-f053a563-d519-4b0d-8152-a54489c13324";
     const wchar_t ZOOMIT_EXIT_EVENT[] = L"Local\\PowerToysZoomIt-ExitEvent-36641ce6-df02-4eac-abea-a3fbf9138220";
 
+    // Path to the events used by PowerDisplay
+    const wchar_t SHOW_POWER_DISPLAY_EVENT[] = L"Local\\PowerToysPowerDisplay-ShowEvent-d8a4e0e3-2c5b-4a1c-9e7f-8b3d6c1a2f4e";
+    const wchar_t TERMINATE_POWER_DISPLAY_EVENT[] = L"Local\\PowerToysPowerDisplay-TerminateEvent-7b9c2e1f-8a5d-4c3e-9f6b-2a1d8c5e3b7a";
+
     // used from quick access window
     const wchar_t CMDPAL_SHOW_EVENT[] = L"Local\\PowerToysCmdPal-ShowEvent-62336fcd-8611-4023-9b30-091a6af4cc5a";
     const wchar_t CMDPAL_EXIT_EVENT[] = L"Local\\PowerToysCmdPal-ExitEvent-eb73f6be-3f22-4b36-aee3-62924ba40bfd";

src/modules/powerdisplay/PowerDisplay/Commands/RelayCommand.cs

@@ -0,0 +1,56 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Windows.Input;
+
+namespace PowerDisplay.Commands
+{
+    /// <summary>
+    /// Basic relay command implementation for parameterless actions
+    /// </summary>
+    public partial class RelayCommand : ICommand
+    {
+        private readonly Action _execute;
+        private readonly Func<bool>? _canExecute;
+
+        public RelayCommand(Action execute, Func<bool>? canExecute = null)
+        {
+            _execute = execute ?? throw new ArgumentNullException(nameof(execute));
+            _canExecute = canExecute;
+        }
+
+        public event EventHandler? CanExecuteChanged;
+
+        public bool CanExecute(object? parameter) => _canExecute?.Invoke() ?? true;
+
+        public void Execute(object? parameter) => _execute();
+
+        public void RaiseCanExecuteChanged() => CanExecuteChanged?.Invoke(this, EventArgs.Empty);
+    }
+
+    /// <summary>
+    /// Generic relay command implementation for parameterized actions
+    /// </summary>
+    /// <typeparam name="T">Type of the command parameter</typeparam>
+    public partial class RelayCommand<T> : ICommand
+    {
+        private readonly Action<T?> _execute;
+        private readonly Func<T?, bool>? _canExecute;
+
+        public RelayCommand(Action<T?> execute, Func<T?, bool>? canExecute = null)
+        {
+            _execute = execute ?? throw new ArgumentNullException(nameof(execute));
+            _canExecute = canExecute;
+        }
+
+        public event EventHandler? CanExecuteChanged;
+
+        public bool CanExecute(object? parameter) => _canExecute?.Invoke((T?)parameter) ?? true;
+
+        public void Execute(object? parameter) => _execute((T?)parameter);
+
+        public void RaiseCanExecuteChanged() => CanExecuteChanged?.Invoke(this, EventArgs.Empty);
+    }
+}

src/modules/powerdisplay/PowerDisplay/Configuration/AppConstants.cs

@@ -0,0 +1,86 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace PowerDisplay.Configuration
+{
+    /// <summary>
+    /// Application-wide constants and configuration values
+    /// </summary>
+    public static class AppConstants
+    {
+        /// <summary>
+        /// State management configuration
+        /// </summary>
+        public static class State
+        {
+            /// <summary>
+            /// Interval in milliseconds to check for pending state changes to save
+            /// </summary>
+            public const int SaveIntervalMs = 2000;
+
+            /// <summary>
+            /// Name of the state file for monitor parameters
+            /// </summary>
+            public const string StateFileName = "monitor_state.json";
+        }
+
+        /// <summary>
+        /// Monitor parameter defaults and ranges
+        /// </summary>
+        public static class MonitorDefaults
+        {
+            // Brightness
+            public const int MinBrightness = 0;
+            public const int MaxBrightness = 100;
+            public const int DefaultBrightness = 50;
+
+            // Color Temperature (Kelvin)
+            public const int MinColorTemp = 2000;  // Warm
+            public const int MaxColorTemp = 10000; // Cool
+            public const int DefaultColorTemp = 6500; // Neutral
+
+            // Contrast
+            public const int MinContrast = 0;
+            public const int MaxContrast = 100;
+            public const int DefaultContrast = 50;
+
+            // Volume
+            public const int MinVolume = 0;
+            public const int MaxVolume = 100;
+            public const int DefaultVolume = 50;
+        }
+
+        /// <summary>
+        /// UI layout and timing constants
+        /// </summary>
+        public static class UI
+        {
+            // Window dimensions
+            public const int WindowWidth = 640;
+            public const int MaxWindowHeight = 650;
+            public const int WindowRightMargin = 10;
+
+            // Animation and layout update delays (milliseconds)
+            public const int AnimationDelayMs = 100;
+            public const int LayoutUpdateDelayMs = 50;
+            public const int MonitorDiscoveryDelayMs = 200;
+        }
+
+        /// <summary>
+        /// Application lifecycle timing constants
+        /// </summary>
+        public static class Lifetime
+        {
+            /// <summary>
+            /// Normal shutdown timeout in milliseconds
+            /// </summary>
+            public const int NormalShutdownTimeoutMs = 1000;
+
+            /// <summary>
+            /// Emergency shutdown timeout in milliseconds
+            /// </summary>
+            public const int EmergencyShutdownTimeoutMs = 500;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Converters/BoolToVisibilityConverter.cs

@@ -0,0 +1,36 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Data;
+
+namespace PowerDisplay.Converters
+{
+    /// <summary>
+    /// Converts boolean values to Visibility
+    /// </summary>
+    public partial class BoolToVisibilityConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, string language)
+        {
+            if (value is bool boolValue)
+            {
+                return boolValue ? Visibility.Visible : Visibility.Collapsed;
+            }
+
+            return Visibility.Collapsed;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, string language)
+        {
+            if (value is Visibility visibility)
+            {
+                return visibility == Visibility.Visible;
+            }
+
+            return false;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Converters/InverseBoolConverter.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using Microsoft.UI.Xaml.Data;
+
+namespace PowerDisplay.Converters
+{
+    /// <summary>
+    /// Converts boolean values to their inverse
+    /// </summary>
+    public partial class InverseBoolConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, string language)
+        {
+            if (value is bool boolValue)
+            {
+                return !boolValue;
+            }
+
+            return true; // Default to enabled if value is not bool
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, string language)
+        {
+            if (value is bool boolValue)
+            {
+                return !boolValue;
+            }
+
+            return false;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Converters/InverseBoolToVisibilityConverter.cs

@@ -0,0 +1,36 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Data;
+
+namespace PowerDisplay.Converters
+{
+    /// <summary>
+    /// Converts boolean values to Visibility (inverted)
+    /// </summary>
+    public partial class InverseBoolToVisibilityConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, string language)
+        {
+            if (value is bool boolValue)
+            {
+                return boolValue ? Visibility.Collapsed : Visibility.Visible;
+            }
+
+            return Visibility.Visible;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, string language)
+        {
+            if (value is Visibility visibility)
+            {
+                return visibility != Visibility.Visible;
+            }
+
+            return true;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Interfaces/IMonitorController.cs

@@ -0,0 +1,145 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using PowerDisplay.Core.Models;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay.Core.Interfaces
+{
+    /// <summary>
+    /// Monitor controller interface
+    /// </summary>
+    public interface IMonitorController
+    {
+        /// <summary>
+        /// Controller name
+        /// </summary>
+        string Name { get; }
+
+        /// <summary>
+        /// Supported monitor type
+        /// </summary>
+        MonitorType SupportedType { get; }
+
+        /// <summary>
+        /// Checks whether the specified monitor can be controlled
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Whether the monitor can be controlled</returns>
+        Task<bool> CanControlMonitorAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Gets monitor brightness
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Brightness information</returns>
+        Task<BrightnessInfo> GetBrightnessAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Sets monitor brightness
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="brightness">Brightness value (0-100)</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Operation result</returns>
+        Task<MonitorOperationResult> SetBrightnessAsync(Monitor monitor, int brightness, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Discovers supported monitors
+        /// </summary>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>List of monitors</returns>
+        Task<IEnumerable<Monitor>> DiscoverMonitorsAsync(CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Validates monitor connection status
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Whether the monitor is connected</returns>
+        Task<bool> ValidateConnectionAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Gets monitor contrast
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Contrast information</returns>
+        Task<BrightnessInfo> GetContrastAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Sets monitor contrast
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="contrast">Contrast value (0-100)</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Operation result</returns>
+        Task<MonitorOperationResult> SetContrastAsync(Monitor monitor, int contrast, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Gets monitor volume
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Volume information</returns>
+        Task<BrightnessInfo> GetVolumeAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Sets monitor volume
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="volume">Volume value (0-100)</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Operation result</returns>
+        Task<MonitorOperationResult> SetVolumeAsync(Monitor monitor, int volume, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Gets monitor color temperature
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Color temperature information</returns>
+        Task<BrightnessInfo> GetColorTemperatureAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Sets monitor color temperature
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="colorTemperature">Color temperature value (2000-10000K)</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Operation result</returns>
+        Task<MonitorOperationResult> SetColorTemperatureAsync(Monitor monitor, int colorTemperature, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Gets monitor capabilities string (DDC/CI)
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Capabilities string</returns>
+        Task<string> GetCapabilitiesStringAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Saves current settings to monitor
+        /// </summary>
+        /// <param name="monitor">Monitor object</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns>Operation result</returns>
+        Task<MonitorOperationResult> SaveCurrentSettingsAsync(Monitor monitor, CancellationToken cancellationToken = default);
+
+        /// <summary>
+        /// Releases resources
+        /// </summary>
+        void Dispose();
+    }
+
+    // IMonitorManager interface removed - YAGNI principle
+    // Only one implementation exists (MonitorManager), so interface abstraction is unnecessary
+    // This simplifies the codebase and eliminates maintenance overhead
+}

src/modules/powerdisplay/PowerDisplay/Core/Interfaces/MonitorListChangedEventArgs.cs

@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using PowerDisplay.Core.Models;
+
+namespace PowerDisplay.Core.Interfaces
+{
+    /// <summary>
+    /// Monitor list changed event arguments
+    /// </summary>
+    public class MonitorListChangedEventArgs : EventArgs
+    {
+        public IReadOnlyList<Monitor> AddedMonitors { get; }
+
+        public IReadOnlyList<Monitor> RemovedMonitors { get; }
+
+        public IReadOnlyList<Monitor> AllMonitors { get; }
+
+        public MonitorListChangedEventArgs(
+            IReadOnlyList<Monitor> addedMonitors,
+            IReadOnlyList<Monitor> removedMonitors,
+            IReadOnlyList<Monitor> allMonitors)
+        {
+            AddedMonitors = addedMonitors;
+            RemovedMonitors = removedMonitors;
+            AllMonitors = allMonitors;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Interfaces/MonitorStatusChangedEventArgs.cs

@@ -0,0 +1,71 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using PowerDisplay.Core.Models;
+
+namespace PowerDisplay.Core.Interfaces
+{
+    /// <summary>
+    /// Monitor status changed event arguments
+    /// </summary>
+    public class MonitorStatusChangedEventArgs : EventArgs
+    {
+        public Monitor Monitor { get; }
+
+        public int? OldBrightness { get; }
+
+        public int NewBrightness { get; }
+
+        public bool? OldAvailability { get; }
+
+        public bool NewAvailability { get; }
+
+        public string Message { get; }
+
+        public ChangeType Type { get; }
+
+        public enum ChangeType
+        {
+            Brightness,
+            Contrast,
+            Volume,
+            ColorTemperature,
+            Availability,
+            General,
+        }
+
+        public MonitorStatusChangedEventArgs(
+            Monitor monitor,
+            int? oldBrightness,
+            int newBrightness,
+            bool? oldAvailability,
+            bool newAvailability)
+        {
+            Monitor = monitor;
+            OldBrightness = oldBrightness;
+            NewBrightness = newBrightness;
+            OldAvailability = oldAvailability;
+            NewAvailability = newAvailability;
+            Message = $"Brightness changed from {oldBrightness} to {newBrightness}";
+            Type = ChangeType.Brightness;
+        }
+
+        public MonitorStatusChangedEventArgs(
+            Monitor monitor,
+            string message,
+            ChangeType changeType)
+        {
+            Monitor = monitor;
+            Message = message;
+            Type = changeType;
+
+            // Set defaults for compatibility
+            OldBrightness = null;
+            NewBrightness = monitor.CurrentBrightness;
+            OldAvailability = null;
+            NewAvailability = monitor.IsAvailable;
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Models/BrightnessInfo.cs

@@ -0,0 +1,90 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace PowerDisplay.Core.Models
+{
+    /// <summary>
+    /// Brightness information structure
+    /// </summary>
+    public readonly struct BrightnessInfo
+    {
+        /// <summary>
+        /// Current brightness value
+        /// </summary>
+        public int Current { get; }
+
+        /// <summary>
+        /// Minimum brightness value
+        /// </summary>
+        public int Minimum { get; }
+
+        /// <summary>
+        /// Maximum brightness value
+        /// </summary>
+        public int Maximum { get; }
+
+        /// <summary>
+        /// Whether the brightness information is valid
+        /// </summary>
+        public bool IsValid { get; }
+
+        /// <summary>
+        /// Timestamp when the brightness information was obtained
+        /// </summary>
+        public DateTime Timestamp { get; }
+
+        public BrightnessInfo(int current, int minimum, int maximum)
+        {
+            Current = current;
+            Minimum = minimum;
+            Maximum = maximum;
+            IsValid = current >= minimum && current <= maximum && maximum > minimum;
+            Timestamp = DateTime.Now;
+        }
+
+        public BrightnessInfo(int current, int maximum)
+            : this(current, 0, maximum)
+        {
+        }
+
+        /// <summary>
+        /// Creates invalid brightness information
+        /// </summary>
+        public static BrightnessInfo Invalid => new(-1, -1, -1);
+
+        /// <summary>
+        /// Converts brightness value to percentage (0-100)
+        /// </summary>
+        public int ToPercentage()
+        {
+            if (!IsValid || Maximum == Minimum)
+            {
+                return 0;
+            }
+
+            return (int)Math.Round((double)(Current - Minimum) * 100 / (Maximum - Minimum));
+        }
+
+        /// <summary>
+        /// Creates brightness value from percentage
+        /// </summary>
+        public int FromPercentage(int percentage)
+        {
+            if (!IsValid)
+            {
+                return -1;
+            }
+
+            percentage = Math.Clamp(percentage, 0, 100);
+            return Minimum + (int)Math.Round((double)(Maximum - Minimum) * percentage / 100);
+        }
+
+        public override string ToString()
+        {
+            return IsValid ? $"{Current}/{Maximum} ({ToPercentage()}%)" : "Invalid";
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Models/Monitor.cs

@@ -0,0 +1,249 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using PowerDisplay.Configuration;
+
+namespace PowerDisplay.Core.Models
+{
+    /// <summary>
+    /// Monitor model that implements property change notification
+    /// </summary>
+    public partial class Monitor : INotifyPropertyChanged
+    {
+        private int _currentBrightness;
+        private int _currentColorTemperature = AppConstants.MonitorDefaults.DefaultColorTemp;
+        private bool _isAvailable = true;
+
+        /// <summary>
+        /// Unique identifier (based on hardware ID)
+        /// </summary>
+        public string Id { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Hardware ID (EDID format like GSM5C6D)
+        /// </summary>
+        public string HardwareId { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Display name
+        /// </summary>
+        public string Name { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Monitor type
+        /// </summary>
+        public MonitorType Type { get; set; } = MonitorType.Unknown;
+
+        /// <summary>
+        /// Current brightness (0-100)
+        /// </summary>
+        public int CurrentBrightness
+        {
+            get => _currentBrightness;
+            set
+            {
+                var clamped = Math.Clamp(value, MinBrightness, MaxBrightness);
+                if (_currentBrightness != clamped)
+                {
+                    _currentBrightness = clamped;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Minimum brightness value
+        /// </summary>
+        public int MinBrightness { get; set; }
+
+        /// <summary>
+        /// Maximum brightness value
+        /// </summary>
+        public int MaxBrightness { get; set; } = 100;
+
+        /// <summary>
+        /// Current color temperature (2000-10000K)
+        /// </summary>
+        public int CurrentColorTemperature
+        {
+            get => _currentColorTemperature;
+            set
+            {
+                var clamped = Math.Clamp(value, MinColorTemperature, MaxColorTemperature);
+                if (_currentColorTemperature != clamped)
+                {
+                    _currentColorTemperature = clamped;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Minimum color temperature value
+        /// </summary>
+        public int MinColorTemperature { get; set; } = AppConstants.MonitorDefaults.MinColorTemp;
+
+        /// <summary>
+        /// Maximum color temperature value
+        /// </summary>
+        public int MaxColorTemperature { get; set; } = AppConstants.MonitorDefaults.MaxColorTemp;
+
+        /// <summary>
+        /// Whether supports color temperature adjustment
+        /// </summary>
+        public bool SupportsColorTemperature { get; set; } = true;
+
+        /// <summary>
+        /// Whether supports contrast adjustment
+        /// </summary>
+        public bool SupportsContrast => Capabilities.HasFlag(MonitorCapabilities.Contrast);
+
+        /// <summary>
+        /// Whether supports volume adjustment (for audio-capable monitors)
+        /// </summary>
+        public bool SupportsVolume => Capabilities.HasFlag(MonitorCapabilities.Volume);
+
+        private int _currentContrast = 50;
+        private int _currentVolume = 50;
+
+        /// <summary>
+        /// Current contrast (0-100)
+        /// </summary>
+        public int CurrentContrast
+        {
+            get => _currentContrast;
+            set
+            {
+                var clamped = Math.Clamp(value, MinContrast, MaxContrast);
+                if (_currentContrast != clamped)
+                {
+                    _currentContrast = clamped;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Minimum contrast value
+        /// </summary>
+        public int MinContrast { get; set; }
+
+        /// <summary>
+        /// Maximum contrast value
+        /// </summary>
+        public int MaxContrast { get; set; } = 100;
+
+        /// <summary>
+        /// Current volume (0-100)
+        /// </summary>
+        public int CurrentVolume
+        {
+            get => _currentVolume;
+            set
+            {
+                var clamped = Math.Clamp(value, MinVolume, MaxVolume);
+                if (_currentVolume != clamped)
+                {
+                    _currentVolume = clamped;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Minimum volume value
+        /// </summary>
+        public int MinVolume { get; set; }
+
+        /// <summary>
+        /// Maximum volume value
+        /// </summary>
+        public int MaxVolume { get; set; } = 100;
+
+        /// <summary>
+        /// Whether available/online
+        /// </summary>
+        public bool IsAvailable
+        {
+            get => _isAvailable;
+            set
+            {
+                if (_isAvailable != value)
+                {
+                    _isAvailable = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        /// <summary>
+        /// Physical monitor handle (for DDC/CI)
+        /// </summary>
+        public IntPtr Handle { get; set; } = IntPtr.Zero;
+
+        /// <summary>
+        /// Device key - unique identifier part of device path (like Twinkle Tray's deviceKey)
+        /// </summary>
+        public string DeviceKey { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Instance name (used by WMI)
+        /// </summary>
+        public string InstanceName { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Manufacturer information
+        /// </summary>
+        public string Manufacturer { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Connection type (HDMI, DP, VGA, etc.)
+        /// </summary>
+        public string ConnectionType { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Communication method (DDC/CI, WMI, HDR API, etc.)
+        /// </summary>
+        public string CommunicationMethod { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Supported control methods
+        /// </summary>
+        public MonitorCapabilities Capabilities { get; set; } = MonitorCapabilities.None;
+
+        /// <summary>
+        /// Last update time
+        /// </summary>
+        public DateTime LastUpdate { get; set; } = DateTime.Now;
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+
+        protected virtual void OnPropertyChanged([CallerMemberName] string? propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+
+        public override string ToString()
+        {
+            return $"{Name} ({Type}) - {CurrentBrightness}%";
+        }
+
+        /// <summary>
+        /// Update monitor status
+        /// </summary>
+        public void UpdateStatus(int brightness, bool isAvailable = true)
+        {
+            IsAvailable = isAvailable;
+            if (isAvailable)
+            {
+                CurrentBrightness = brightness;
+                LastUpdate = DateTime.Now;
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Models/MonitorCapabilities.cs

@@ -0,0 +1,52 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace PowerDisplay.Core.Models
+{
+    /// <summary>
+    /// Monitor control capabilities flags
+    /// </summary>
+    [Flags]
+    public enum MonitorCapabilities
+    {
+        None = 0,
+
+        /// <summary>
+        /// Supports brightness control
+        /// </summary>
+        Brightness = 1 << 0,
+
+        /// <summary>
+        /// Supports contrast control
+        /// </summary>
+        Contrast = 1 << 1,
+
+        /// <summary>
+        /// Supports DDC/CI protocol
+        /// </summary>
+        DdcCi = 1 << 2,
+
+        /// <summary>
+        /// Supports WMI control
+        /// </summary>
+        Wmi = 1 << 3,
+
+        /// <summary>
+        /// Supports HDR
+        /// </summary>
+        Hdr = 1 << 4,
+
+        /// <summary>
+        /// Supports high-level monitor API
+        /// </summary>
+        HighLevel = 1 << 5,
+
+        /// <summary>
+        /// Supports volume control
+        /// </summary>
+        Volume = 1 << 6,
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Models/MonitorOperationResult.cs

@@ -0,0 +1,58 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace PowerDisplay.Core.Models
+{
+    /// <summary>
+    /// Monitor operation result
+    /// </summary>
+    public readonly struct MonitorOperationResult
+    {
+        /// <summary>
+        /// Whether the operation was successful
+        /// </summary>
+        public bool IsSuccess { get; }
+
+        /// <summary>
+        /// Error message
+        /// </summary>
+        public string? ErrorMessage { get; }
+
+        /// <summary>
+        /// System error code
+        /// </summary>
+        public int? ErrorCode { get; }
+
+        /// <summary>
+        /// Operation timestamp
+        /// </summary>
+        public DateTime Timestamp { get; }
+
+        private MonitorOperationResult(bool isSuccess, string? errorMessage = null, int? errorCode = null)
+        {
+            IsSuccess = isSuccess;
+            ErrorMessage = errorMessage;
+            ErrorCode = errorCode;
+            Timestamp = DateTime.Now;
+        }
+
+        /// <summary>
+        /// Creates a successful result
+        /// </summary>
+        public static MonitorOperationResult Success() => new(true);
+
+        /// <summary>
+        /// Creates a failed result
+        /// </summary>
+        public static MonitorOperationResult Failure(string errorMessage, int? errorCode = null)
+            => new(false, errorMessage, errorCode);
+
+        public override string ToString()
+        {
+            return IsSuccess ? "Success" : $"Failed: {ErrorMessage}";
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Models/MonitorType.cs

@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace PowerDisplay.Core.Models
+{
+    /// <summary>
+    /// Monitor type enumeration
+    /// </summary>
+    public enum MonitorType
+    {
+        /// <summary>
+        /// Unknown type
+        /// </summary>
+        Unknown,
+
+        /// <summary>
+        /// Internal display (laptop screen, controlled via WMI)
+        /// </summary>
+        Internal,
+
+        /// <summary>
+        /// External display (controlled via DDC/CI)
+        /// </summary>
+        External,
+
+        /// <summary>
+        /// HDR display (controlled via Display Config API)
+        /// </summary>
+        HDR,
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/MonitorManager.cs

@@ -0,0 +1,455 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+using PowerDisplay.Core.Interfaces;
+using PowerDisplay.Core.Models;
+using PowerDisplay.Core.Utils;
+using PowerDisplay.Native.DDC;
+using PowerDisplay.Native.WMI;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay.Core
+{
+    /// <summary>
+    /// Monitor manager for unified control of all monitors
+    /// No interface abstraction - KISS principle (only one implementation needed)
+    /// </summary>
+    public partial class MonitorManager : IDisposable
+    {
+        private readonly List<Monitor> _monitors = new();
+        private readonly List<IMonitorController> _controllers = new();
+        private readonly SemaphoreSlim _discoveryLock = new(1, 1);
+        private bool _disposed;
+
+        public IReadOnlyList<Monitor> Monitors => _monitors.AsReadOnly();
+
+        public event EventHandler<MonitorListChangedEventArgs>? MonitorsChanged;
+
+        public MonitorManager()
+        {
+            // Initialize controllers
+            InitializeControllers();
+        }
+
+        /// <summary>
+        /// Initialize controllers
+        /// </summary>
+        private void InitializeControllers()
+        {
+            try
+            {
+                // DDC/CI controller (external monitors)
+                _controllers.Add(new DdcCiController());
+            }
+            catch (Exception ex)
+            {
+                Logger.LogWarning($"Failed to initialize DDC/CI controller: {ex.Message}");
+            }
+
+            try
+            {
+                // WMI controller (internal monitors)
+                // First check if WMI is available
+                if (WmiController.IsWmiAvailable())
+                {
+                    _controllers.Add(new WmiController());
+                }
+                else
+                {
+                    Logger.LogInfo("WMI brightness control not available on this system");
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogWarning($"Failed to initialize WMI controller: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Discover all monitors
+        /// </summary>
+        public async Task<IReadOnlyList<Monitor>> DiscoverMonitorsAsync(CancellationToken cancellationToken = default)
+        {
+            await _discoveryLock.WaitAsync(cancellationToken);
+
+            try
+            {
+                var oldMonitors = _monitors.ToList();
+                var newMonitors = new List<Monitor>();
+
+                // Discover monitors supported by all controllers in parallel
+                var discoveryTasks = _controllers.Select(async controller =>
+                {
+                    try
+                    {
+                        var monitors = await controller.DiscoverMonitorsAsync(cancellationToken);
+                        return (Controller: controller, Monitors: monitors.ToList());
+                    }
+                    catch (Exception ex)
+                    {
+                        // If a controller fails, log the error and return empty list
+                        Logger.LogWarning($"Controller {controller.Name} discovery failed: {ex.Message}");
+                        return (Controller: controller, Monitors: new List<Monitor>());
+                    }
+                });
+
+                var results = await Task.WhenAll(discoveryTasks);
+
+                // Collect all discovered monitors
+                foreach (var (controller, monitors) in results)
+                {
+                    foreach (var monitor in monitors)
+                    {
+                        // Verify if monitor can be controlled
+                        if (await controller.CanControlMonitorAsync(monitor, cancellationToken))
+                        {
+                            // Get current brightness
+                            try
+                            {
+                                var brightnessInfo = await controller.GetBrightnessAsync(monitor, cancellationToken);
+                                if (brightnessInfo.IsValid)
+                                {
+                                    monitor.CurrentBrightness = brightnessInfo.ToPercentage();
+                                    monitor.MinBrightness = brightnessInfo.Minimum;
+                                    monitor.MaxBrightness = brightnessInfo.Maximum;
+                                }
+                            }
+                            catch (Exception ex)
+                            {
+                                // If unable to get brightness, use default values
+                                Logger.LogWarning($"Failed to get brightness for monitor {monitor.Id}: {ex.Message}");
+                            }
+
+                            newMonitors.Add(monitor);
+                        }
+                    }
+                }
+
+                // Update monitor list
+                _monitors.Clear();
+                _monitors.AddRange(newMonitors);
+
+                // Trigger change events
+                var addedMonitors = newMonitors.Where(m => !oldMonitors.Any(o => o.Id == m.Id)).ToList();
+                var removedMonitors = oldMonitors.Where(o => !newMonitors.Any(m => m.Id == o.Id)).ToList();
+
+                if (addedMonitors.Count > 0 || removedMonitors.Count > 0)
+                {
+                    MonitorsChanged?.Invoke(this, new MonitorListChangedEventArgs(
+                        addedMonitors.AsReadOnly(),
+                        removedMonitors.AsReadOnly(),
+                        _monitors.AsReadOnly()));
+                }
+
+                return _monitors.AsReadOnly();
+            }
+            finally
+            {
+                _discoveryLock.Release();
+            }
+        }
+
+        /// <summary>
+        /// Get brightness of the specified monitor
+        /// </summary>
+        public async Task<BrightnessInfo> GetBrightnessAsync(string monitorId, CancellationToken cancellationToken = default)
+        {
+            var monitor = GetMonitor(monitorId);
+            if (monitor == null)
+            {
+                return BrightnessInfo.Invalid;
+            }
+
+            var controller = GetControllerForMonitor(monitor);
+            if (controller == null)
+            {
+                return BrightnessInfo.Invalid;
+            }
+
+            try
+            {
+                var brightnessInfo = await controller.GetBrightnessAsync(monitor, cancellationToken);
+
+                // Update cached brightness value
+                if (brightnessInfo.IsValid)
+                {
+                    monitor.UpdateStatus(brightnessInfo.ToPercentage(), true);
+                }
+
+                return brightnessInfo;
+            }
+            catch (Exception ex)
+            {
+                // Mark monitor as unavailable
+                Logger.LogError($"Failed to get brightness for monitor {monitorId}: {ex.Message}");
+                monitor.IsAvailable = false;
+                return BrightnessInfo.Invalid;
+            }
+        }
+
+        /// <summary>
+        /// Set brightness of the specified monitor
+        /// </summary>
+        public async Task<MonitorOperationResult> SetBrightnessAsync(string monitorId, int brightness, CancellationToken cancellationToken = default)
+        {
+            Logger.LogDebug($"[MonitorManager] SetBrightnessAsync called for {monitorId}, brightness={brightness}");
+
+            var monitor = GetMonitor(monitorId);
+            if (monitor == null)
+            {
+                Logger.LogError($"[MonitorManager] Monitor not found: {monitorId}");
+                return MonitorOperationResult.Failure("Monitor not found");
+            }
+
+            Logger.LogDebug($"[MonitorManager] Monitor found: {monitor.Id}, Type={monitor.Type}, Handle=0x{monitor.Handle:X}, DeviceKey={monitor.DeviceKey}");
+
+            var controller = GetControllerForMonitor(monitor);
+            if (controller == null)
+            {
+                Logger.LogError($"[MonitorManager] No controller available for monitor {monitorId}, Type={monitor.Type}");
+                return MonitorOperationResult.Failure("No controller available for this monitor");
+            }
+
+            Logger.LogDebug($"[MonitorManager] Controller found: {controller.GetType().Name}");
+
+            try
+            {
+                Logger.LogDebug($"[MonitorManager] Calling controller.SetBrightnessAsync for {monitor.Id}");
+                var result = await controller.SetBrightnessAsync(monitor, brightness, cancellationToken);
+                Logger.LogDebug($"[MonitorManager] controller.SetBrightnessAsync returned: IsSuccess={result.IsSuccess}, ErrorMessage={result.ErrorMessage}");
+
+                if (result.IsSuccess)
+                {
+                    // Update monitor status
+                    monitor.UpdateStatus(brightness, true);
+                }
+                else
+                {
+                    // If setting fails, monitor may be unavailable
+                    monitor.IsAvailable = false;
+                }
+
+                return result;
+            }
+            catch (Exception ex)
+            {
+                monitor.IsAvailable = false;
+                return MonitorOperationResult.Failure($"Exception setting brightness: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Set brightness of all monitors
+        /// </summary>
+        public async Task<IEnumerable<MonitorOperationResult>> SetAllBrightnessAsync(int brightness, CancellationToken cancellationToken = default)
+        {
+            var tasks = _monitors
+                .Where(m => m.IsAvailable)
+                .Select(async monitor =>
+                {
+                    try
+                    {
+                        return await SetBrightnessAsync(monitor.Id, brightness, cancellationToken);
+                    }
+                    catch (Exception ex)
+                    {
+                        return MonitorOperationResult.Failure($"Failed to set brightness for {monitor.Name}: {ex.Message}");
+                    }
+                });
+
+            return await Task.WhenAll(tasks);
+        }
+
+        /// <summary>
+        /// Set contrast of the specified monitor
+        /// </summary>
+        public Task<MonitorOperationResult> SetContrastAsync(string monitorId, int contrast, CancellationToken cancellationToken = default)
+            => ExecuteMonitorOperationAsync(
+                monitorId,
+                contrast,
+                (ctrl, mon, val, ct) => ctrl.SetContrastAsync(mon, val, ct),
+                (mon, val) => mon.CurrentContrast = val,
+                cancellationToken);
+
+        /// <summary>
+        /// Set volume of the specified monitor
+        /// </summary>
+        public Task<MonitorOperationResult> SetVolumeAsync(string monitorId, int volume, CancellationToken cancellationToken = default)
+            => ExecuteMonitorOperationAsync(
+                monitorId,
+                volume,
+                (ctrl, mon, val, ct) => ctrl.SetVolumeAsync(mon, val, ct),
+                (mon, val) => mon.CurrentVolume = val,
+                cancellationToken);
+
+        /// <summary>
+        /// Get monitor color temperature
+        /// </summary>
+        public async Task<BrightnessInfo> GetColorTemperatureAsync(string monitorId, CancellationToken cancellationToken = default)
+        {
+            var monitor = GetMonitor(monitorId);
+            if (monitor == null)
+            {
+                return BrightnessInfo.Invalid;
+            }
+
+            var controller = GetControllerForMonitor(monitor);
+            if (controller == null)
+            {
+                return BrightnessInfo.Invalid;
+            }
+
+            try
+            {
+                return await controller.GetColorTemperatureAsync(monitor, cancellationToken);
+            }
+            catch (Exception)
+            {
+                return BrightnessInfo.Invalid;
+            }
+        }
+
+        /// <summary>
+        /// Set monitor color temperature
+        /// </summary>
+        public Task<MonitorOperationResult> SetColorTemperatureAsync(string monitorId, int colorTemperature, CancellationToken cancellationToken = default)
+            => ExecuteMonitorOperationAsync(
+                monitorId,
+                colorTemperature,
+                (ctrl, mon, val, ct) => ctrl.SetColorTemperatureAsync(mon, val, ct),
+                (mon, val) => mon.CurrentColorTemperature = val,
+                cancellationToken);
+
+        /// <summary>
+        /// Initialize color temperature for a monitor (async operation)
+        /// </summary>
+        public async Task InitializeColorTemperatureAsync(string monitorId, CancellationToken cancellationToken = default)
+        {
+            try
+            {
+                var tempInfo = await GetColorTemperatureAsync(monitorId, cancellationToken);
+                if (tempInfo.IsValid)
+                {
+                    var monitor = GetMonitor(monitorId);
+                    if (monitor != null)
+                    {
+                        // Convert VCP value to approximate Kelvin temperature
+                        // This is a rough mapping - actual values depend on monitor implementation
+                        var kelvin = ConvertVcpValueToKelvin(tempInfo.Current, tempInfo.Maximum);
+                        monitor.CurrentColorTemperature = kelvin;
+
+                        Logger.LogInfo($"Initialized color temperature for {monitorId}: {kelvin}K (VCP: {tempInfo.Current}/{tempInfo.Maximum})");
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogWarning($"Failed to initialize color temperature for {monitorId}: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Convert VCP value to approximate Kelvin temperature (uses unified converter)
+        /// </summary>
+        private static int ConvertVcpValueToKelvin(int vcpValue, int maxVcpValue)
+        {
+            return ColorTemperatureConverter.VcpToKelvin(vcpValue, maxVcpValue);
+        }
+
+        /// <summary>
+        /// Get monitor by ID
+        /// </summary>
+        public Monitor? GetMonitor(string monitorId)
+        {
+            return _monitors.FirstOrDefault(m => m.Id == monitorId);
+        }
+
+        /// <summary>
+        /// Get controller for the monitor
+        /// </summary>
+        private IMonitorController? GetControllerForMonitor(Monitor monitor)
+        {
+            return _controllers.FirstOrDefault(c => c.SupportedType == monitor.Type);
+        }
+
+        /// <summary>
+        /// Generic helper to execute monitor operations with common error handling.
+        /// Eliminates code duplication across Set* methods.
+        /// </summary>
+        private async Task<MonitorOperationResult> ExecuteMonitorOperationAsync<T>(
+            string monitorId,
+            T value,
+            Func<IMonitorController, Monitor, T, CancellationToken, Task<MonitorOperationResult>> operation,
+            Action<Monitor, T> onSuccess,
+            CancellationToken cancellationToken = default)
+        {
+            var monitor = GetMonitor(monitorId);
+            if (monitor == null)
+            {
+                Logger.LogError($"[MonitorManager] Monitor not found: {monitorId}");
+                return MonitorOperationResult.Failure("Monitor not found");
+            }
+
+            var controller = GetControllerForMonitor(monitor);
+            if (controller == null)
+            {
+                Logger.LogError($"[MonitorManager] No controller available for monitor {monitorId}, Type={monitor.Type}");
+                return MonitorOperationResult.Failure("No controller available for this monitor");
+            }
+
+            try
+            {
+                var result = await operation(controller, monitor, value, cancellationToken);
+
+                if (result.IsSuccess)
+                {
+                    onSuccess(monitor, value);
+                    monitor.LastUpdate = DateTime.Now;
+                }
+                else
+                {
+                    monitor.IsAvailable = false;
+                }
+
+                return result;
+            }
+            catch (Exception ex)
+            {
+                monitor.IsAvailable = false;
+                Logger.LogError($"[MonitorManager] Operation failed for {monitorId}: {ex.Message}");
+                return MonitorOperationResult.Failure($"Exception: {ex.Message}");
+            }
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!_disposed && disposing)
+            {
+                _discoveryLock?.Dispose();
+
+                // Release all controllers
+                foreach (var controller in _controllers)
+                {
+                    controller?.Dispose();
+                }
+
+                _controllers.Clear();
+                _monitors.Clear();
+                _disposed = true;
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Core/Utils/ColorTemperatureConverter.cs

@@ -0,0 +1,89 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace PowerDisplay.Core.Utils
+{
+    /// <summary>
+    /// Utility class for converting between Kelvin color temperature and VCP values.
+    /// Centralizes temperature conversion logic to eliminate code duplication (KISS principle).
+    /// </summary>
+    public static class ColorTemperatureConverter
+    {
+        /// <summary>
+        /// Minimum color temperature in Kelvin (warm)
+        /// </summary>
+        public const int MinKelvin = 2000;
+
+        /// <summary>
+        /// Maximum color temperature in Kelvin (cool)
+        /// </summary>
+        public const int MaxKelvin = 10000;
+
+        /// <summary>
+        /// Convert VCP value to Kelvin temperature
+        /// </summary>
+        /// <param name="vcpValue">Current VCP value</param>
+        /// <param name="vcpMax">Maximum VCP value</param>
+        /// <returns>Temperature in Kelvin (2000-10000K)</returns>
+        public static int VcpToKelvin(int vcpValue, int vcpMax)
+        {
+            if (vcpMax <= 0)
+            {
+                return (MinKelvin + MaxKelvin) / 2; // Default to neutral 6000K
+            }
+
+            // Normalize VCP value to 0-1 range
+            double normalized = Math.Clamp((double)vcpValue / vcpMax, 0.0, 1.0);
+
+            // Map to Kelvin range
+            int kelvin = (int)(MinKelvin + (normalized * (MaxKelvin - MinKelvin)));
+
+            return Math.Clamp(kelvin, MinKelvin, MaxKelvin);
+        }
+
+        /// <summary>
+        /// Convert Kelvin temperature to VCP value
+        /// </summary>
+        /// <param name="kelvin">Temperature in Kelvin (2000-10000K)</param>
+        /// <param name="vcpMax">Maximum VCP value</param>
+        /// <returns>VCP value (0 to vcpMax)</returns>
+        public static int KelvinToVcp(int kelvin, int vcpMax)
+        {
+            // Clamp input to valid range
+            kelvin = Math.Clamp(kelvin, MinKelvin, MaxKelvin);
+
+            // Normalize kelvin to 0-1 range
+            double normalized = (double)(kelvin - MinKelvin) / (MaxKelvin - MinKelvin);
+
+            // Map to VCP range
+            int vcpValue = (int)(normalized * vcpMax);
+
+            return Math.Clamp(vcpValue, 0, vcpMax);
+        }
+
+        /// <summary>
+        /// Check if a temperature value is in valid Kelvin range
+        /// </summary>
+        public static bool IsValidKelvin(int kelvin)
+        {
+            return kelvin >= MinKelvin && kelvin <= MaxKelvin;
+        }
+
+        /// <summary>
+        /// Get a human-readable description of color temperature
+        /// </summary>
+        public static string GetTemperatureDescription(int kelvin)
+        {
+            return kelvin switch
+            {
+                < 3500 => "Warm",
+                < 5500 => "Neutral",
+                < 7500 => "Cool",
+                _ => "Very Cool",
+            };
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/GlobalUsings.cs

@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.CompilerServices;
+
+// Enable compile-time marshalling for all P/Invoke declarations
+// This allows LibraryImport to handle array marshalling and achieve 100% coverage
+[assembly: DisableRuntimeMarshalling]

src/modules/powerdisplay/PowerDisplay/Helpers/MonitorStateManager.cs

@@ -0,0 +1,270 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text.Json;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+using PowerDisplay.Configuration;
+using PowerDisplay.Serialization;
+
+namespace PowerDisplay.Helpers
+{
+    /// <summary>
+    /// Manages monitor parameter state in a separate file from main settings.
+    /// This avoids FileSystemWatcher feedback loops by separating read-only config (settings.json)
+    /// from frequently-updated state (monitor_state.json).
+    /// Simplified to use direct save strategy for reliability and simplicity (KISS principle).
+    /// </summary>
+    public partial class MonitorStateManager : IDisposable
+    {
+        private readonly string _stateFilePath;
+        private readonly Dictionary<string, MonitorState> _states = new();
+        private readonly object _lock = new object();
+
+        private bool _disposed;
+
+        /// <summary>
+        /// Monitor state data (internal tracking, not serialized)
+        /// </summary>
+        private sealed class MonitorState
+        {
+            public int Brightness { get; set; }
+
+            public int ColorTemperature { get; set; }
+
+            public int Contrast { get; set; }
+
+            public int Volume { get; set; }
+        }
+
+        public MonitorStateManager()
+        {
+            // Store state file in same location as settings.json but with different name
+            var settingsPath = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            var powerToysPath = Path.Combine(settingsPath, "Microsoft", "PowerToys", "PowerDisplay");
+
+            if (!Directory.Exists(powerToysPath))
+            {
+                Directory.CreateDirectory(powerToysPath);
+            }
+
+            _stateFilePath = Path.Combine(powerToysPath, AppConstants.State.StateFileName);
+
+            // Load existing state if available
+            LoadStateFromDisk();
+
+            Logger.LogInfo($"MonitorStateManager initialized with direct-save strategy, state file: {_stateFilePath}");
+        }
+
+        /// <summary>
+        /// Update monitor parameter and save immediately to disk.
+        /// Uses HardwareId as the stable key.
+        /// Direct-save strategy ensures no data loss and simplifies code (KISS principle).
+        /// </summary>
+        public void UpdateMonitorParameter(string hardwareId, string property, int value)
+        {
+            try
+            {
+                if (string.IsNullOrEmpty(hardwareId))
+                {
+                    Logger.LogWarning($"Cannot update monitor parameter: HardwareId is empty");
+                    return;
+                }
+
+                lock (_lock)
+                {
+                    // Get or create state entry using HardwareId
+                    if (!_states.TryGetValue(hardwareId, out var state))
+                    {
+                        state = new MonitorState();
+                        _states[hardwareId] = state;
+                    }
+
+                    // Update the specific property
+                    switch (property)
+                    {
+                        case "Brightness":
+                            state.Brightness = value;
+                            break;
+                        case "ColorTemperature":
+                            state.ColorTemperature = value;
+                            break;
+                        case "Contrast":
+                            state.Contrast = value;
+                            break;
+                        case "Volume":
+                            state.Volume = value;
+                            break;
+                        default:
+                            Logger.LogWarning($"Unknown property: {property}");
+                            return;
+                    }
+                }
+
+                // Save immediately after update - simple and reliable!
+                SaveStateToDisk();
+
+                Logger.LogTrace($"[State] Updated and saved {property}={value} for monitor HardwareId='{hardwareId}'");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to update monitor parameter: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Get saved parameters for a monitor using HardwareId
+        /// </summary>
+        public (int Brightness, int ColorTemperature, int Contrast, int Volume)? GetMonitorParameters(string hardwareId)
+        {
+            if (string.IsNullOrEmpty(hardwareId))
+            {
+                return null;
+            }
+
+            lock (_lock)
+            {
+                if (_states.TryGetValue(hardwareId, out var state))
+                {
+                    return (state.Brightness, state.ColorTemperature, state.Contrast, state.Volume);
+                }
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Check if state exists for a monitor (by HardwareId)
+        /// </summary>
+        public bool HasMonitorState(string hardwareId)
+        {
+            if (string.IsNullOrEmpty(hardwareId))
+            {
+                return false;
+            }
+
+            lock (_lock)
+            {
+                return _states.ContainsKey(hardwareId);
+            }
+        }
+
+        /// <summary>
+        /// Load state from disk
+        /// </summary>
+        private void LoadStateFromDisk()
+        {
+            try
+            {
+                if (!File.Exists(_stateFilePath))
+                {
+                    Logger.LogInfo("[State] No existing state file found, starting fresh");
+                    return;
+                }
+
+                var json = File.ReadAllText(_stateFilePath);
+                var stateFile = JsonSerializer.Deserialize(json, AppJsonContext.Default.MonitorStateFile);
+
+                if (stateFile?.Monitors != null)
+                {
+                    lock (_lock)
+                    {
+                        foreach (var kvp in stateFile.Monitors)
+                        {
+                            var monitorKey = kvp.Key; // Should be HardwareId (e.g., "GSM5C6D")
+                            var entry = kvp.Value;
+
+                            _states[monitorKey] = new MonitorState
+                            {
+                                Brightness = entry.Brightness,
+                                ColorTemperature = entry.ColorTemperature,
+                                Contrast = entry.Contrast,
+                                Volume = entry.Volume,
+                            };
+                        }
+                    }
+
+                    Logger.LogInfo($"[State] Loaded state for {stateFile.Monitors.Count} monitors from {_stateFilePath}");
+                    Logger.LogInfo($"[State] Monitor keys in state file: {string.Join(", ", stateFile.Monitors.Keys)}");
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to load monitor state: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Save current state to disk immediately.
+        /// Simplified direct-save approach - no timer, no dirty flags, just save!
+        /// </summary>
+        private void SaveStateToDisk()
+        {
+            try
+            {
+                if (_disposed)
+                {
+                    return;
+                }
+
+                // Build state file
+                var stateFile = new MonitorStateFile
+                {
+                    LastUpdated = DateTime.Now,
+                };
+
+                var now = DateTime.Now;
+
+                lock (_lock)
+                {
+                    foreach (var kvp in _states)
+                    {
+                        var monitorId = kvp.Key;
+                        var state = kvp.Value;
+
+                        stateFile.Monitors[monitorId] = new MonitorStateEntry
+                        {
+                            Brightness = state.Brightness,
+                            ColorTemperature = state.ColorTemperature,
+                            Contrast = state.Contrast,
+                            Volume = state.Volume,
+                            LastUpdated = now,
+                        };
+                    }
+                }
+
+                // Write to disk
+                var json = JsonSerializer.Serialize(stateFile, AppJsonContext.Default.MonitorStateFile);
+                File.WriteAllText(_stateFilePath, json);
+
+                Logger.LogDebug($"[State] Saved state for {stateFile.Monitors.Count} monitors");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to save monitor state: {ex.Message}");
+            }
+        }
+
+        public void Dispose()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            lock (_lock)
+            {
+                _disposed = true;
+            }
+
+            // State is already saved with each update, no need for final flush!
+            Logger.LogInfo("MonitorStateManager disposed");
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Helpers/ResourceLoaderInstance.cs

@@ -0,0 +1,18 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using Microsoft.Windows.ApplicationModel.Resources;
+
+namespace PowerDisplay.Helpers
+{
+    public static class ResourceLoaderInstance
+    {
+        public static ResourceLoader ResourceLoader { get; private set; }
+
+        static ResourceLoaderInstance()
+        {
+            ResourceLoader = new ResourceLoader("PowerToys.PowerDisplay.pri");
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Helpers/SettingsDeepLink.cs

@@ -0,0 +1,43 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Diagnostics;
+using System.IO;
+using ManagedCommon;
+
+namespace PowerDisplay.Helpers
+{
+    /// <summary>
+    /// Helper class to open PowerToys Settings application.
+    /// Simplified version for PowerDisplay module (AOT compatible).
+    /// </summary>
+    internal static class SettingsDeepLink
+    {
+        /// <summary>
+        /// Opens PowerToys Settings to PowerDisplay page
+        /// </summary>
+        public static void OpenPowerDisplaySettings()
+        {
+            try
+            {
+                // PowerDisplay is a WinUI3 app, PowerToys.exe is in parent directory
+                var directoryPath = Path.Combine(AppContext.BaseDirectory, "..", "PowerToys.exe");
+
+                var startInfo = new ProcessStartInfo(directoryPath)
+                {
+                    Arguments = "--open-settings=PowerDisplay",
+                    UseShellExecute = true,
+                };
+
+                Process.Start(startInfo);
+                Logger.LogInfo("Opened PowerToys Settings to PowerDisplay page");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to open PowerToys Settings: {ex.Message}");
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Helpers/SimpleDebouncer.cs

@@ -0,0 +1,106 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+
+namespace PowerDisplay.Helpers
+{
+    /// <summary>
+    /// Simple debouncer that delays execution of an action until a quiet period.
+    /// Replaces the complex PropertyUpdateQueue with a much simpler approach (KISS principle).
+    /// </summary>
+    public partial class SimpleDebouncer : IDisposable
+    {
+        private readonly int _delayMs;
+        private readonly object _lock = new object();
+        private CancellationTokenSource? _cts;
+        private bool _disposed;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="SimpleDebouncer"/> class.
+        /// Create a debouncer with specified delay
+        /// </summary>
+        /// <param name="delayMs">Delay in milliseconds before executing action</param>
+        public SimpleDebouncer(int delayMs = 300)
+        {
+            _delayMs = delayMs;
+        }
+
+        /// <summary>
+        /// Debounce an async action. Cancels previous invocation if still pending.
+        /// </summary>
+        /// <param name="action">Async action to execute after delay</param>
+        public async void Debounce(Func<Task> action)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            CancellationTokenSource cts;
+
+            lock (_lock)
+            {
+                // Cancel previous invocation
+                _cts?.Cancel();
+                _cts = new CancellationTokenSource();
+                cts = _cts;
+            }
+
+            try
+            {
+                // Wait for quiet period
+                await Task.Delay(_delayMs, cts.Token);
+
+                // Execute action if not cancelled
+                if (!cts.Token.IsCancellationRequested)
+                {
+                    await action();
+                }
+            }
+            catch (OperationCanceledException)
+            {
+                // Expected when debouncing - a newer call cancelled this one
+                Logger.LogTrace("Debounced action cancelled (replaced by newer call)");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Debounced action failed: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Debounce a synchronous action
+        /// </summary>
+        public void Debounce(Action action)
+        {
+            Debounce(() =>
+            {
+                action();
+                return Task.CompletedTask;
+            });
+        }
+
+        public void Dispose()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            lock (_lock)
+            {
+                _disposed = true;
+                _cts?.Cancel();
+                _cts?.Dispose();
+                _cts = null;
+            }
+
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Helpers/TrayIconHelper.cs

@@ -0,0 +1,484 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Drawing;
+using System.Runtime.InteropServices;
+using ManagedCommon;
+using Microsoft.UI.Xaml;
+using PowerDisplay.Native;
+using static PowerDisplay.Native.PInvoke;
+
+namespace PowerDisplay.Helpers
+{
+    /// <summary>
+    /// System tray icon helper class
+    /// </summary>
+    public partial class TrayIconHelper : IDisposable
+    {
+        private const uint NifMessage = 0x00000001;
+        private const uint NifIcon = 0x00000002;
+        private const uint NifTip = 0x00000004;
+        private const uint NifInfo = 0x00000010;
+
+        private const uint NimAdd = 0x00000000;
+        private const uint NimModify = 0x00000001;
+        private const uint NimDelete = 0x00000002;
+
+        private const uint WmUser = 0x0400;
+        private const uint WmTrayicon = WmUser + 1;
+        private const uint WmLbuttonup = 0x0202;
+        private const uint WmRbuttonup = 0x0205;
+        private const uint WmCommand = 0x0111;
+
+        private uint _wmTaskbarCreated; // TaskbarCreated message ID
+
+        // Menu item IDs
+        private const int IdShow = 1001;
+        private const int IdExit = 1002;
+        private const int IdRefresh = 1003;
+        private const int IdSettings = 1004;
+
+        private delegate IntPtr WndProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam);
+
+        private const uint MfString = 0x00000000;
+        private const uint MfSeparator = 0x00000800;
+        private const uint TpmLeftalign = 0x0000;
+        private const uint TpmReturncmd = 0x0100;
+
+        private const int SwHide = 0;
+        private const int SwShow = 5;
+
+        private IntPtr _messageWindowHandle;
+        private NOTIFYICONDATA _notifyIconData;
+        private bool _isDisposed;
+        private WndProc _wndProc;
+        private Window _mainWindow;
+        private Action? _onShowWindow;
+        private Action? _onExitApplication;
+        private Action? _onRefresh;
+        private Action? _onSettings;
+        private bool _isWindowVisible = true;
+        private System.Drawing.Icon? _trayIcon;  // Keep icon reference to prevent garbage collection
+
+        public TrayIconHelper(Window mainWindow)
+        {
+            _mainWindow = mainWindow;
+            _wndProc = WindowProc;
+
+            // Register TaskbarCreated message
+            _wmTaskbarCreated = RegisterWindowMessage("TaskbarCreated");
+            Logger.LogInfo($"Registered TaskbarCreated message: {_wmTaskbarCreated}");
+
+            if (!CreateMessageWindow())
+            {
+                Logger.LogError("Failed to create message window");
+                return;
+            }
+
+            CreateTrayIcon();
+        }
+
+        /// <summary>
+        /// Set callback functions
+        /// </summary>
+        public void SetCallbacks(Action onShow, Action onExit, Action? onRefresh = null, Action? onSettings = null)
+        {
+            _onShowWindow = onShow;
+            _onExitApplication = onExit;
+            _onRefresh = onRefresh;
+            _onSettings = onSettings;
+        }
+
+        /// <summary>
+        /// Create message window - using system predefined Message window class
+        /// </summary>
+        private bool CreateMessageWindow()
+        {
+            try
+            {
+                Logger.LogDebug("Creating message window using system Message class...");
+
+                // Use system predefined "Message" window class, no registration needed
+                // HWND_MESSAGE (-3) creates pure message window, no hInstance needed
+                _messageWindowHandle = CreateWindowEx(
+                    0,                      // dwExStyle
+                    "Message",              // lpClassName - system predefined message window class
+                    string.Empty,           // lpWindowName
+                    0,                      // dwStyle
+                    0,
+                    0,
+                    0,
+                    0, // x, y, width, height
+                    new IntPtr(-3), // hWndParent = HWND_MESSAGE (pure message window)
+                    IntPtr.Zero, // hMenu
+                    IntPtr.Zero, // hInstance - not needed
+                    IntPtr.Zero); // lpParam
+
+                if (_messageWindowHandle == IntPtr.Zero)
+                {
+                    var error = Marshal.GetLastWin32Error();
+                    Logger.LogError($"CreateWindowEx failed with error: {error}");
+                    return false;
+                }
+
+                Logger.LogInfo($"Message window created successfully: {_messageWindowHandle}");
+
+                // Set window procedure to handle our messages
+                SetWindowLongPtr(_messageWindowHandle, -4, Marshal.GetFunctionPointerForDelegate(_wndProc));
+
+                return true;
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"CreateMessageWindow exception: {ex.Message}");
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// Create tray icon
+        /// </summary>
+        private unsafe void CreateTrayIcon()
+        {
+            if (_messageWindowHandle == IntPtr.Zero)
+            {
+                Logger.LogError("Cannot create tray icon: invalid message window handle");
+                return;
+            }
+
+            // First try to delete any existing old icon (if any)
+            var tempData = new NOTIFYICONDATA
+            {
+                CbSize = (uint)sizeof(NOTIFYICONDATA),
+                HWnd = _messageWindowHandle,
+                UID = 1,
+            };
+            Shell_NotifyIcon(NimDelete, ref tempData);
+
+            // Get icon handle
+            var iconHandle = GetDefaultIcon();
+            if (iconHandle == IntPtr.Zero)
+            {
+                Logger.LogError("Cannot create tray icon: invalid icon handle");
+                return;
+            }
+
+            _notifyIconData = new NOTIFYICONDATA
+            {
+                CbSize = (uint)sizeof(NOTIFYICONDATA),
+                HWnd = _messageWindowHandle,
+                UID = 1,
+                UFlags = NifMessage | NifIcon | NifTip,
+                UCallbackMessage = WmTrayicon,
+                HIcon = iconHandle,
+            };
+            _notifyIconData.SetTip("Power Display");
+
+            // Retry mechanism: try up to 3 times to create tray icon
+            const int maxRetries = 3;
+            const int retryDelayMs = 500;
+
+            for (int attempt = 1; attempt <= maxRetries; attempt++)
+            {
+                Logger.LogDebug($"Creating tray icon (attempt {attempt}/{maxRetries})...");
+
+                bool result = Shell_NotifyIcon(NimAdd, ref _notifyIconData);
+                if (result)
+                {
+                    Logger.LogInfo($"Tray icon created successfully on attempt {attempt}");
+                    return;
+                }
+
+                var lastError = Marshal.GetLastWin32Error();
+                Logger.LogWarning($"Failed to create tray icon on attempt {attempt}. Error: {lastError}");
+
+                // Analyze specific error and provide suggestions
+                switch (lastError)
+                {
+                    case 0: // ERROR_SUCCESS - may be false success
+                        Logger.LogWarning("Shell_NotifyIcon returned false but GetLastWin32Error is 0");
+                        break;
+                    case 1400: // ERROR_INVALID_WINDOW_HANDLE
+                        Logger.LogWarning("Invalid window handle - message window may not be properly created");
+                        break;
+                    case 1418: // ERROR_THREAD_1_INACTIVE
+                        Logger.LogWarning("Thread inactive - may need to wait for Explorer to be ready");
+                        break;
+                    case 1414: // ERROR_INVALID_ICON_HANDLE
+                        Logger.LogWarning("Invalid icon handle - icon may have been garbage collected");
+                        break;
+                    default:
+                        Logger.LogWarning($"Unexpected error code: {lastError}");
+                        break;
+                }
+
+                // If not the last attempt, wait and retry
+                if (attempt < maxRetries)
+                {
+                    Logger.LogDebug($"Retrying in {retryDelayMs}ms...");
+                    System.Threading.Thread.Sleep(retryDelayMs);
+
+                    // Re-get icon handle to prevent handle invalidation
+                    iconHandle = GetDefaultIcon();
+                    _notifyIconData.HIcon = iconHandle;
+                }
+            }
+
+            Logger.LogError($"Failed to create tray icon after {maxRetries} attempts");
+        }
+
+        /// <summary>
+        /// Get default icon
+        /// </summary>
+        private IntPtr GetDefaultIcon()
+        {
+            try
+            {
+                // First release previous icon
+                _trayIcon?.Dispose();
+                _trayIcon = null;
+
+                // Try to load icon from Assets folder in exe directory
+                var exePath = System.Diagnostics.Process.GetCurrentProcess().MainModule?.FileName;
+                if (!string.IsNullOrEmpty(exePath))
+                {
+                    var exeDir = System.IO.Path.GetDirectoryName(exePath);
+                    if (!string.IsNullOrEmpty(exeDir))
+                    {
+                        var iconPath = System.IO.Path.Combine(exeDir, "Assets", "PowerDisplay.ico");
+
+                        Logger.LogDebug($"Attempting to load icon from: {iconPath}");
+
+                        if (System.IO.File.Exists(iconPath))
+                        {
+                            // Create icon and save as class member to prevent garbage collection
+                            _trayIcon = new System.Drawing.Icon(iconPath);
+                            Logger.LogInfo($"Successfully loaded custom icon from {iconPath}");
+                            return _trayIcon.Handle;
+                        }
+                        else
+                        {
+                            Logger.LogWarning($"Icon file not found at: {iconPath}");
+                        }
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to load PowerDisplay icon: {ex.Message}");
+                _trayIcon?.Dispose();
+                _trayIcon = null;
+            }
+
+            // If loading fails, use system default icon
+            var systemIconHandle = LoadIcon(IntPtr.Zero, new IntPtr(32512)); // IDI_APPLICATION
+            Logger.LogInfo($"Using system default icon: {systemIconHandle}");
+            return systemIconHandle;
+        }
+
+        /// <summary>
+        /// Window message processing
+        /// </summary>
+        private IntPtr WindowProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam)
+        {
+            if (msg == _wmTaskbarCreated)
+            {
+                // Explorer restarted, need to recreate tray icon
+                Logger.LogInfo("TaskbarCreated message received - recreating tray icon");
+                CreateTrayIcon();
+                return IntPtr.Zero;
+            }
+
+            switch (msg)
+            {
+                case WmTrayicon:
+                    HandleTrayIconMessage(lParam);
+                    break;
+                case WmCommand:
+                    HandleMenuCommand(wParam);
+                    break;
+            }
+
+            return DefWindowProc(hWnd, msg, wParam, lParam);
+        }
+
+        /// <summary>
+        /// Handle tray icon messages
+        /// </summary>
+        private void HandleTrayIconMessage(IntPtr lParam)
+        {
+            switch ((uint)lParam)
+            {
+                case WmLbuttonup:
+                    // Left click - show/hide window
+                    ToggleWindowVisibility();
+                    break;
+                case WmRbuttonup:
+                    // Right click - show menu
+                    ShowContextMenu();
+                    break;
+            }
+        }
+
+        /// <summary>
+        /// Toggle window visibility state
+        /// </summary>
+        private void ToggleWindowVisibility()
+        {
+            _isWindowVisible = !_isWindowVisible;
+            if (_isWindowVisible)
+            {
+                _onShowWindow?.Invoke();
+            }
+            else
+            {
+                // Hide window logic will be implemented in MainWindow
+                if (_mainWindow != null)
+                {
+                    var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(_mainWindow);
+                    ShowWindow(hWnd, SwHide);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Show right-click menu
+        /// </summary>
+        private void ShowContextMenu()
+        {
+            var hMenu = CreatePopupMenu();
+
+            AppendMenu(hMenu, MfString, IdShow, _isWindowVisible ? "Hide Window" : "Show Window");
+            if (_onRefresh != null)
+            {
+                AppendMenu(hMenu, MfString, IdRefresh, "Refresh Monitors");
+            }
+
+            if (_onSettings != null)
+            {
+                AppendMenu(hMenu, MfString, IdSettings, "Settings");
+            }
+
+            AppendMenu(hMenu, MfSeparator, 0, string.Empty);
+            AppendMenu(hMenu, MfString, IdExit, "Exit");
+
+            GetCursorPos(out POINT pt);
+            SetForegroundWindow(_messageWindowHandle);
+
+            var cmd = TrackPopupMenu(hMenu, TpmLeftalign | TpmReturncmd, pt.X, pt.Y, 0, _messageWindowHandle, IntPtr.Zero);
+
+            if (cmd != 0)
+            {
+                HandleMenuCommand(new IntPtr(cmd));
+            }
+
+            DestroyMenu(hMenu);
+        }
+
+        /// <summary>
+        /// Handle menu commands
+        /// </summary>
+        private void HandleMenuCommand(IntPtr commandId)
+        {
+            switch (commandId.ToInt32())
+            {
+                case IdShow:
+                    ToggleWindowVisibility();
+                    break;
+                case IdRefresh:
+                    _onRefresh?.Invoke();
+                    break;
+                case IdSettings:
+                    _onSettings?.Invoke();
+                    break;
+                case IdExit:
+                    _onExitApplication?.Invoke();
+                    break;
+            }
+        }
+
+        /// <summary>
+        /// Show balloon tip
+        /// </summary>
+        public void ShowBalloonTip(string title, string text, uint timeout = 3000)
+        {
+            _notifyIconData.UFlags |= NifInfo;
+            _notifyIconData.SetInfoTitle(title);
+            _notifyIconData.SetInfo(text);
+            _notifyIconData.UTimeout = timeout;
+            _notifyIconData.DwInfoFlags = 1; // NIIF_INFO
+
+            Shell_NotifyIcon(NimModify, ref _notifyIconData);
+        }
+
+        /// <summary>
+        /// Update tray icon tooltip text
+        /// </summary>
+        public void UpdateTooltip(string tooltip)
+        {
+            _notifyIconData.SetTip(tooltip);
+            Shell_NotifyIcon(NimModify, ref _notifyIconData);
+        }
+
+        /// <summary>
+        /// Recreate tray icon (for failure recovery)
+        /// </summary>
+        public void RecreateTrayIcon()
+        {
+            Logger.LogInfo("Manually recreating tray icon...");
+            CreateTrayIcon();
+        }
+
+        public void Dispose()
+        {
+            if (!_isDisposed)
+            {
+                Logger.LogDebug("Disposing TrayIconHelper...");
+
+                // Remove tray icon
+                try
+                {
+                    Shell_NotifyIcon(NimDelete, ref _notifyIconData);
+                    Logger.LogInfo("Tray icon removed successfully");
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"Error removing tray icon: {ex.Message}");
+                }
+
+                // Release icon resources
+                try
+                {
+                    _trayIcon?.Dispose();
+                    _trayIcon = null;
+                    Logger.LogInfo("Icon resources disposed successfully");
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"Error disposing icon: {ex.Message}");
+                }
+
+                // Destroy message window
+                try
+                {
+                    if (_messageWindowHandle != IntPtr.Zero)
+                    {
+                        DestroyWindow(_messageWindowHandle);
+                        _messageWindowHandle = IntPtr.Zero;
+                        Logger.LogInfo("Message window destroyed successfully");
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"Error destroying message window: {ex.Message}");
+                }
+
+                _isDisposed = true;
+                GC.SuppressFinalize(this);
+                Logger.LogDebug("TrayIconHelper disposed completely");
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Helpers/TypePreservation.cs

@@ -0,0 +1,81 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Diagnostics.CodeAnalysis;
+
+namespace PowerDisplay.Helpers
+{
+    /// <summary>
+    /// This class ensures types used in XAML are preserved during AOT compilation.
+    /// Framework types cannot have attributes added directly to their definitions since they're external types.
+    /// Use DynamicDependency to preserve all members of these WinUI3 framework types.
+    /// </summary>
+    internal static class TypePreservation
+    {
+        // Core WinUI3 Controls used in XAML
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Window))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Application))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.Grid))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.Border))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ScrollViewer))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.StackPanel))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ItemsControl))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.Slider))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.TextBlock))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.Button))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.FontIcon))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ProgressRing))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.InfoBar))]
+
+        // Animation and Transform types
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.Storyboard))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.DoubleAnimation))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.CubicEase))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.TranslateTransform))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.TransitionCollection))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.EntranceThemeTransition))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.RepositionThemeTransition))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Animation.EasingFunctionBase))]
+
+        // Template and Resource types
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.DataTemplate))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ItemsPanelTemplate))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Style))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.FontIconSource))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.ResourceDictionary))]
+
+        // Text and Document types
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Documents.Run))]
+
+        // Layout types
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.RowDefinition))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ColumnDefinition))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.RowDefinitionCollection))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ColumnDefinitionCollection))]
+
+        // Media types for brushes and visuals
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.SolidColorBrush))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Brush))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Media.Transform))]
+
+        // Core UI element types
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.UIElement))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.FrameworkElement))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.DependencyObject))]
+
+        // Thickness and other value types used in XAML (structs, not enums)
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Thickness))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.CornerRadius))]
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.GridLength))]
+
+        // ToolTip service used in buttons
+        [DynamicDependency(DynamicallyAccessedMemberTypes.All, typeof(Microsoft.UI.Xaml.Controls.ToolTipService))]
+
+        public static void PreserveTypes()
+        {
+            // This method exists only to hold the DynamicDependency attributes above.
+            // It must be called to ensure the types are not trimmed during AOT compilation.
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/DDC/DdcCiController.cs

@@ -0,0 +1,637 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+using PowerDisplay.Core.Interfaces;
+using PowerDisplay.Core.Models;
+using static PowerDisplay.Native.NativeConstants;
+using static PowerDisplay.Native.NativeDelegates;
+using static PowerDisplay.Native.PInvoke;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+// Type aliases matching Windows API naming conventions for better readability when working with native structures.
+// These uppercase aliases are used consistently throughout this file to match Win32 API documentation.
+using MONITORINFOEX = PowerDisplay.Native.MonitorInfoEx;
+using PHYSICAL_MONITOR = PowerDisplay.Native.PhysicalMonitor;
+using RECT = PowerDisplay.Native.Rect;
+
+namespace PowerDisplay.Native.DDC
+{
+    /// <summary>
+    /// DDC/CI monitor controller for controlling external monitors
+    /// </summary>
+    public partial class DdcCiController : IMonitorController, IDisposable
+    {
+        private readonly PhysicalMonitorHandleManager _handleManager = new();
+        private readonly VcpCodeResolver _vcpResolver = new();
+        private readonly MonitorDiscoveryHelper _discoveryHelper;
+
+        private bool _disposed;
+
+        public DdcCiController()
+        {
+            _discoveryHelper = new MonitorDiscoveryHelper(_vcpResolver);
+        }
+
+        public string Name => "DDC/CI Monitor Controller";
+
+        public MonitorType SupportedType => MonitorType.External;
+
+        /// <summary>
+        /// Check if the specified monitor can be controlled
+        /// </summary>
+        public async Task<bool> CanControlMonitorAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            if (monitor.Type != MonitorType.External)
+            {
+                return false;
+            }
+
+            return await Task.Run(
+                () =>
+                {
+                    var physicalHandle = GetPhysicalHandle(monitor);
+                    return physicalHandle != IntPtr.Zero && DdcCiNative.ValidateDdcCiConnection(physicalHandle);
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get monitor brightness
+        /// </summary>
+        public async Task<BrightnessInfo> GetBrightnessAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                    var physicalHandle = GetPhysicalHandle(monitor);
+                    if (physicalHandle == IntPtr.Zero)
+                    {
+                        return BrightnessInfo.Invalid;
+                    }
+
+                    // First try high-level API
+                    if (DdcCiNative.TryGetMonitorBrightness(physicalHandle, out uint minBrightness, out uint currentBrightness, out uint maxBrightness))
+                    {
+                        return new BrightnessInfo((int)currentBrightness, (int)minBrightness, (int)maxBrightness);
+                    }
+
+                    // Try different VCP codes
+                    var vcpCode = _vcpResolver.GetBrightnessVcpCode(monitor.Id, physicalHandle);
+                    if (vcpCode.HasValue && DdcCiNative.TryGetVCPFeature(physicalHandle, vcpCode.Value, out uint current, out uint max))
+                    {
+                        return new BrightnessInfo((int)current, 0, (int)max);
+                    }
+
+                    return BrightnessInfo.Invalid;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Set monitor brightness
+        /// </summary>
+        public async Task<MonitorOperationResult> SetBrightnessAsync(Monitor monitor, int brightness, CancellationToken cancellationToken = default)
+        {
+            brightness = Math.Clamp(brightness, 0, 100);
+
+            return await Task.Run(
+                () =>
+                {
+                    var physicalHandle = GetPhysicalHandle(monitor);
+                    if (physicalHandle == IntPtr.Zero)
+                    {
+                        return MonitorOperationResult.Failure("No physical handle found");
+                    }
+
+                    try
+                    {
+                        var currentInfo = GetBrightnessInfo(monitor, physicalHandle);
+                        if (!currentInfo.IsValid)
+                        {
+                            return MonitorOperationResult.Failure("Cannot read current brightness");
+                        }
+
+                        uint targetValue = (uint)currentInfo.FromPercentage(brightness);
+
+                        // First try high-level API
+                        if (DdcCiNative.TrySetMonitorBrightness(physicalHandle, targetValue))
+                        {
+                            return MonitorOperationResult.Success();
+                        }
+
+                        // Try VCP codes
+                        var vcpCode = _vcpResolver.GetBrightnessVcpCode(monitor.Id, physicalHandle);
+                        if (vcpCode.HasValue && DdcCiNative.TrySetVCPFeature(physicalHandle, vcpCode.Value, targetValue))
+                        {
+                            return MonitorOperationResult.Success();
+                        }
+
+                        var lastError = GetLastError();
+                        return MonitorOperationResult.Failure($"Failed to set brightness via DDC/CI", (int)lastError);
+                    }
+                    catch (Exception ex)
+                    {
+                        return MonitorOperationResult.Failure($"Exception setting brightness: {ex.Message}");
+                    }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get monitor contrast
+        /// </summary>
+        public Task<BrightnessInfo> GetContrastAsync(Monitor monitor, CancellationToken cancellationToken = default)
+            => GetVcpFeatureAsync(monitor, NativeConstants.VcpCodeContrast, cancellationToken);
+
+        /// <summary>
+        /// Set monitor contrast
+        /// </summary>
+        public Task<MonitorOperationResult> SetContrastAsync(Monitor monitor, int contrast, CancellationToken cancellationToken = default)
+            => SetVcpFeatureAsync(monitor, NativeConstants.VcpCodeContrast, contrast, 0, 100, cancellationToken);
+
+        /// <summary>
+        /// Get monitor volume
+        /// </summary>
+        public Task<BrightnessInfo> GetVolumeAsync(Monitor monitor, CancellationToken cancellationToken = default)
+            => GetVcpFeatureAsync(monitor, NativeConstants.VcpCodeVolume, cancellationToken);
+
+        /// <summary>
+        /// Set monitor volume
+        /// </summary>
+        public Task<MonitorOperationResult> SetVolumeAsync(Monitor monitor, int volume, CancellationToken cancellationToken = default)
+            => SetVcpFeatureAsync(monitor, NativeConstants.VcpCodeVolume, volume, 0, 100, cancellationToken);
+
+        /// <summary>
+        /// Get monitor color temperature
+        /// </summary>
+        public async Task<BrightnessInfo> GetColorTemperatureAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                    if (monitor.Handle == IntPtr.Zero)
+                    {
+                        return BrightnessInfo.Invalid;
+                    }
+
+                    // Try different VCP codes for color temperature
+                    var vcpCode = _vcpResolver.GetColorTemperatureVcpCode(monitor.Id, monitor.Handle);
+                    if (vcpCode.HasValue && DdcCiNative.TryGetVCPFeature(monitor.Handle, vcpCode.Value, out uint current, out uint max))
+                    {
+                        return new BrightnessInfo((int)current, 0, (int)max);
+                    }
+
+                    return BrightnessInfo.Invalid;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Set monitor color temperature
+        /// </summary>
+        public async Task<MonitorOperationResult> SetColorTemperatureAsync(Monitor monitor, int colorTemperature, CancellationToken cancellationToken = default)
+        {
+            colorTemperature = Math.Clamp(colorTemperature, 2000, 10000);
+
+            return await Task.Run(
+                () =>
+                {
+                    if (monitor.Handle == IntPtr.Zero)
+                    {
+                        return MonitorOperationResult.Failure("Invalid monitor handle");
+                    }
+
+                    try
+                    {
+                        // Get current color temperature info to understand the range
+                        var currentInfo = _vcpResolver.GetCurrentColorTemperature(monitor.Handle);
+                        if (!currentInfo.IsValid)
+                        {
+                            return MonitorOperationResult.Failure("Cannot read current color temperature");
+                        }
+
+                        // Convert Kelvin temperature to VCP value
+                        uint targetValue = _vcpResolver.ConvertKelvinToVcpValue(colorTemperature, currentInfo);
+
+                        // Try to set using the best available VCP code
+                        var vcpCode = _vcpResolver.GetColorTemperatureVcpCode(monitor.Id, monitor.Handle);
+                        if (vcpCode.HasValue && DdcCiNative.TrySetVCPFeature(monitor.Handle, vcpCode.Value, targetValue))
+                        {
+                            Logger.LogInfo($"Successfully set color temperature to {colorTemperature}K via DDC/CI (VCP 0x{vcpCode.Value:X2})");
+                            return MonitorOperationResult.Success();
+                        }
+
+                        var lastError = GetLastError();
+                        return MonitorOperationResult.Failure($"Failed to set color temperature via DDC/CI", (int)lastError);
+                    }
+                    catch (Exception ex)
+                    {
+                        return MonitorOperationResult.Failure($"Exception setting color temperature: {ex.Message}");
+                    }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get monitor capabilities string
+        /// </summary>
+        public async Task<string> GetCapabilitiesStringAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                if (monitor.Handle == IntPtr.Zero)
+                {
+                    return string.Empty;
+                }
+
+                try
+                {
+                    if (GetCapabilitiesStringLength(monitor.Handle, out uint length) && length > 0)
+                    {
+                        var buffer = System.Runtime.InteropServices.Marshal.AllocHGlobal((int)length);
+                        try
+                        {
+                            if (CapabilitiesRequestAndCapabilitiesReply(monitor.Handle, buffer, length))
+                            {
+                                return System.Runtime.InteropServices.Marshal.PtrToStringAnsi(buffer) ?? string.Empty;
+                            }
+                        }
+                        finally
+                        {
+                            System.Runtime.InteropServices.Marshal.FreeHGlobal(buffer);
+                        }
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogWarning($"Failed to get capabilities string: {ex.Message}");
+                }
+
+                return string.Empty;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Save current settings
+        /// </summary>
+        public async Task<MonitorOperationResult> SaveCurrentSettingsAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                if (monitor.Handle == IntPtr.Zero)
+                {
+                    return MonitorOperationResult.Failure("Invalid monitor handle");
+                }
+
+                try
+                {
+                    if (SaveCurrentSettings(monitor.Handle))
+                    {
+                        return MonitorOperationResult.Success();
+                    }
+
+                    var lastError = GetLastError();
+                    return MonitorOperationResult.Failure($"Failed to save settings", (int)lastError);
+                }
+                catch (Exception ex)
+                {
+                    return MonitorOperationResult.Failure($"Exception saving settings: {ex.Message}");
+                }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Discover supported monitors
+        /// </summary>
+        public async Task<IEnumerable<Monitor>> DiscoverMonitorsAsync(CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                async () =>
+                {
+                var monitors = new List<Monitor>();
+                var newHandleMap = new Dictionary<string, IntPtr>();
+
+                try
+                {
+                    // Get all display devices with stable device IDs (Twinkle Tray style)
+                    var displayDevices = DdcCiNative.GetAllDisplayDevices();
+                    Logger.LogInfo($"DDC: Found {displayDevices.Count} display devices via EnumDisplayDevices");
+
+                    // Also get hardware info for friendly names
+                    var monitorDisplayInfo = DdcCiNative.GetAllMonitorDisplayInfo();
+                    Logger.LogDebug($"DDC: GetAllMonitorDisplayInfo returned {monitorDisplayInfo.Count} items");
+
+                    // Enumerate all monitors
+                    var monitorHandles = new List<IntPtr>();
+                    Logger.LogDebug($"DDC: About to call EnumDisplayMonitors...");
+
+                    bool EnumProc(IntPtr hMonitor, IntPtr hdcMonitor, IntPtr lprcMonitor, IntPtr dwData)
+                    {
+                        Logger.LogDebug($"DDC: EnumProc callback - hMonitor=0x{hMonitor:X}");
+                        monitorHandles.Add(hMonitor);
+                        return true;
+                    }
+
+                    bool enumResult = EnumDisplayMonitors(IntPtr.Zero, IntPtr.Zero, EnumProc, IntPtr.Zero);
+                    Logger.LogDebug($"DDC: EnumDisplayMonitors returned {enumResult}, found {monitorHandles.Count} monitor handles");
+
+                    if (!enumResult)
+                    {
+                        Logger.LogWarning($"DDC: EnumDisplayMonitors failed");
+                        return monitors;
+                    }
+
+                    // Get physical handles for each monitor
+                    foreach (var hMonitor in monitorHandles)
+                    {
+                        var adapterName = _discoveryHelper.GetMonitorDeviceId(hMonitor);
+                        if (string.IsNullOrEmpty(adapterName))
+                        {
+                            continue;
+                        }
+
+                        // Sometimes Windows returns NULL handles. Implement Twinkle Tray's retry logic.
+                        // See: twinkle-tray/src/Monitors.js line 617
+                        PHYSICAL_MONITOR[]? physicalMonitors = null;
+                        const int maxRetries = 3;
+                        const int retryDelayMs = 200;
+
+                        for (int attempt = 0; attempt < maxRetries; attempt++)
+                        {
+                            if (attempt > 0)
+                            {
+                                Logger.LogInfo($"DDC: Retry attempt {attempt}/{maxRetries - 1} for hMonitor 0x{hMonitor:X} after {retryDelayMs}ms delay");
+                                await Task.Delay(retryDelayMs, cancellationToken);
+                            }
+
+                            physicalMonitors = _discoveryHelper.GetPhysicalMonitors(hMonitor);
+
+                            if (physicalMonitors == null || physicalMonitors.Length == 0)
+                            {
+                                if (attempt < maxRetries - 1)
+                                {
+                                    Logger.LogWarning($"DDC: GetPhysicalMonitors returned null/empty on attempt {attempt + 1}, will retry");
+                                }
+
+                                continue;
+                            }
+
+                            // Check if any handle is NULL (Twinkle Tray checks handleIsValid)
+                            bool hasNullHandle = false;
+                            for (int i = 0; i < physicalMonitors.Length; i++)
+                            {
+                                if (physicalMonitors[i].HPhysicalMonitor == IntPtr.Zero)
+                                {
+                                    hasNullHandle = true;
+                                    Logger.LogWarning($"DDC: Physical monitor [{i}] has NULL handle on attempt {attempt + 1}");
+                                    break;
+                                }
+                            }
+
+                            if (!hasNullHandle)
+                            {
+                                // Success! All handles are valid
+                                if (attempt > 0)
+                                {
+                                    Logger.LogInfo($"DDC: Successfully obtained valid handles on attempt {attempt + 1}");
+                                }
+
+                                break;
+                            }
+                            else if (attempt < maxRetries - 1)
+                            {
+                                Logger.LogWarning($"DDC: NULL handle detected, will retry (attempt {attempt + 1}/{maxRetries})");
+                                physicalMonitors = null; // Reset for retry
+                            }
+                            else
+                            {
+                                Logger.LogWarning($"DDC: NULL handle still present after {maxRetries} attempts, continuing anyway");
+                            }
+                        }
+
+                        if (physicalMonitors == null || physicalMonitors.Length == 0)
+                        {
+                            Logger.LogWarning($"DDC: Failed to get physical monitors for hMonitor 0x{hMonitor:X} after {maxRetries} attempts");
+                            continue;
+                        }
+
+                        // Match physical monitors with DisplayDeviceInfo (Twinkle Tray logic)
+                        // For each physical monitor on this adapter, find the corresponding DisplayDeviceInfo
+                        for (int i = 0; i < physicalMonitors.Length; i++)
+                        {
+                            var physicalMonitor = physicalMonitors[i];
+                            if (physicalMonitor.HPhysicalMonitor == IntPtr.Zero)
+                            {
+                                continue;
+                            }
+
+                            // Find matching DisplayDeviceInfo for this physical monitor
+                            DisplayDeviceInfo? matchedDevice = null;
+                            int foundCount = 0;
+
+                            foreach (var displayDevice in displayDevices)
+                            {
+                                if (displayDevice.AdapterName == adapterName)
+                                {
+                                    if (foundCount == i)
+                                    {
+                                        matchedDevice = displayDevice;
+                                        break;
+                                    }
+
+                                    foundCount++;
+                                }
+                            }
+
+                            // Determine device key for handle reuse logic
+                            string deviceKey = matchedDevice?.DeviceKey ?? $"{adapterName}_{i}";
+
+                            // Use HandleManager to reuse or create handle
+                            var (handleToUse, reusingOldHandle) = _handleManager.ReuseOrCreateHandle(deviceKey, physicalMonitor.HPhysicalMonitor);
+
+                            // Validate DDC/CI connection for the handle we're going to use
+                            if (!reusingOldHandle && !DdcCiNative.ValidateDdcCiConnection(handleToUse))
+                            {
+                                Logger.LogWarning($"DDC: New handle 0x{handleToUse:X} failed DDC/CI validation, skipping");
+                                continue;
+                            }
+
+                            // Update physical monitor handle to use the correct one
+                            var monitorToCreate = physicalMonitor;
+                            monitorToCreate.HPhysicalMonitor = handleToUse;
+
+                            var monitor = _discoveryHelper.CreateMonitorFromPhysical(monitorToCreate, adapterName, i, monitorDisplayInfo, matchedDevice);
+                            if (monitor != null)
+                            {
+                                Logger.LogInfo($"DDC: Created monitor {monitor.Id} with handle 0x{monitor.Handle:X} (reused: {reusingOldHandle}), deviceKey: {monitor.DeviceKey}");
+                                monitors.Add(monitor);
+
+                                // Store in new map for cleanup
+                                newHandleMap[monitor.DeviceKey] = handleToUse;
+                            }
+                        }
+                    }
+
+                    // Update handle manager with new mapping
+                    _handleManager.UpdateHandleMap(newHandleMap);
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"DDC: DiscoverMonitorsAsync exception: {ex.Message}\nStack: {ex.StackTrace}");
+                }
+                finally
+                {
+                    Logger.LogDebug($"DDC: DiscoverMonitorsAsync returning {monitors.Count} monitors");
+                }
+
+                return monitors;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Validate monitor connection status
+        /// </summary>
+        public async Task<bool> ValidateConnectionAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () => monitor.Handle != IntPtr.Zero && DdcCiNative.ValidateDdcCiConnection(monitor.Handle),
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Generic method to get VCP feature value
+        /// </summary>
+        private async Task<BrightnessInfo> GetVcpFeatureAsync(
+            Monitor monitor,
+            byte vcpCode,
+            CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                    if (monitor.Handle == IntPtr.Zero)
+                    {
+                        return BrightnessInfo.Invalid;
+                    }
+
+                    if (DdcCiNative.TryGetVCPFeature(monitor.Handle, vcpCode, out uint current, out uint max))
+                    {
+                        return new BrightnessInfo((int)current, 0, (int)max);
+                    }
+
+                    return BrightnessInfo.Invalid;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Generic method to set VCP feature value
+        /// </summary>
+        private async Task<MonitorOperationResult> SetVcpFeatureAsync(
+            Monitor monitor,
+            byte vcpCode,
+            int value,
+            int min = 0,
+            int max = 100,
+            CancellationToken cancellationToken = default)
+        {
+            value = Math.Clamp(value, min, max);
+
+            return await Task.Run(
+                () =>
+                {
+                    if (monitor.Handle == IntPtr.Zero)
+                    {
+                        return MonitorOperationResult.Failure("Invalid monitor handle");
+                    }
+
+                    try
+                    {
+                        // Get current value to determine range
+                        var currentInfo = GetVcpFeatureAsync(monitor, vcpCode).Result;
+                        if (!currentInfo.IsValid)
+                        {
+                            return MonitorOperationResult.Failure($"Cannot read current value for VCP 0x{vcpCode:X2}");
+                        }
+
+                        uint targetValue = (uint)currentInfo.FromPercentage(value);
+
+                        if (DdcCiNative.TrySetVCPFeature(monitor.Handle, vcpCode, targetValue))
+                        {
+                            return MonitorOperationResult.Success();
+                        }
+
+                        var lastError = GetLastError();
+                        return MonitorOperationResult.Failure($"Failed to set VCP 0x{vcpCode:X2}", (int)lastError);
+                    }
+                    catch (Exception ex)
+                    {
+                        return MonitorOperationResult.Failure($"Exception setting VCP 0x{vcpCode:X2}: {ex.Message}");
+                    }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get brightness information (with explicit handle)
+        /// </summary>
+        private BrightnessInfo GetBrightnessInfo(Monitor monitor, IntPtr physicalHandle)
+        {
+            if (physicalHandle == IntPtr.Zero)
+            {
+                return BrightnessInfo.Invalid;
+            }
+
+            // First try high-level API
+            if (DdcCiNative.TryGetMonitorBrightness(physicalHandle, out uint min, out uint current, out uint max))
+            {
+                return new BrightnessInfo((int)current, (int)min, (int)max);
+            }
+
+            // Try VCP codes
+            var vcpCode = _vcpResolver.GetBrightnessVcpCode(monitor.Id, physicalHandle);
+            if (vcpCode.HasValue && DdcCiNative.TryGetVCPFeature(physicalHandle, vcpCode.Value, out current, out max))
+            {
+                return new BrightnessInfo((int)current, 0, (int)max);
+            }
+
+            return BrightnessInfo.Invalid;
+        }
+
+        /// <summary>
+        /// Get physical handle for monitor using stable deviceKey
+        /// </summary>
+        private IntPtr GetPhysicalHandle(Monitor monitor)
+        {
+            return _handleManager.GetPhysicalHandle(monitor);
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!_disposed && disposing)
+            {
+                _handleManager?.Dispose();
+                _vcpResolver?.ClearCache();
+                _disposed = true;
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/DDC/DdcCiNative.cs

@@ -0,0 +1,499 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using ManagedCommon;
+using static PowerDisplay.Native.NativeConstants;
+using static PowerDisplay.Native.NativeDelegates;
+using static PowerDisplay.Native.PInvoke;
+
+// 类型别名，兼容 Windows API 命名约定
+using DISPLAY_DEVICE = PowerDisplay.Native.DisplayDevice;
+using DISPLAYCONFIG_DEVICE_INFO_HEADER = PowerDisplay.Native.DISPLAYCONFIG_DEVICE_INFO_HEADER;
+using DISPLAYCONFIG_MODE_INFO = PowerDisplay.Native.DISPLAYCONFIG_MODE_INFO;
+using DISPLAYCONFIG_PATH_INFO = PowerDisplay.Native.DISPLAYCONFIG_PATH_INFO;
+using DISPLAYCONFIG_TARGET_DEVICE_NAME = PowerDisplay.Native.DISPLAYCONFIG_TARGET_DEVICE_NAME;
+using LUID = PowerDisplay.Native.Luid;
+using MONITORINFOEX = PowerDisplay.Native.MonitorInfoEx;
+using PHYSICAL_MONITOR = PowerDisplay.Native.PhysicalMonitor;
+using RECT = PowerDisplay.Native.Rect;
+
+#pragma warning disable SA1649 // File name should match first type name - Multiple related types for DDC/CI
+#pragma warning disable SA1402 // File may only contain a single type - Related DDC/CI types grouped together
+
+namespace PowerDisplay.Native.DDC
+{
+    /// <summary>
+    /// 显示设备信息类
+    /// </summary>
+    public class DisplayDeviceInfo
+    {
+        public string DeviceName { get; set; } = string.Empty;
+
+        public string AdapterName { get; set; } = string.Empty;
+
+        public string DeviceID { get; set; } = string.Empty;
+
+        public string DeviceKey { get; set; } = string.Empty;
+    }
+
+    /// <summary>
+    /// DDC/CI 原生 API 封装
+    /// </summary>
+    public static class DdcCiNative
+    {
+        // Display Configuration 常量
+        public const uint QdcAllPaths = 0x00000001;
+
+        public const uint QdcOnlyActivePaths = 0x00000002;
+
+        public const uint DisplayconfigDeviceInfoGetTargetName = 2;
+
+        // Helper Methods
+
+        /// <summary>
+        /// 获取 VCP 功能值的安全包装
+        /// </summary>
+        /// <param name="hPhysicalMonitor">物理显示器句柄</param>
+        /// <param name="vcpCode">VCP 代码</param>
+        /// <param name="currentValue">当前值</param>
+        /// <param name="maxValue">最大值</param>
+        /// <returns>是否成功</returns>
+        public static bool TryGetVCPFeature(IntPtr hPhysicalMonitor, byte vcpCode, out uint currentValue, out uint maxValue)
+        {
+            currentValue = 0;
+            maxValue = 0;
+
+            if (hPhysicalMonitor == IntPtr.Zero)
+            {
+                return false;
+            }
+
+            try
+            {
+                return GetVCPFeatureAndVCPFeatureReply(hPhysicalMonitor, vcpCode, IntPtr.Zero, out currentValue, out maxValue);
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// 设置 VCP 功能值的安全包装
+        /// </summary>
+        /// <param name="hPhysicalMonitor">物理显示器句柄</param>
+        /// <param name="vcpCode">VCP 代码</param>
+        /// <param name="value">新值</param>
+        /// <returns>是否成功</returns>
+        public static bool TrySetVCPFeature(IntPtr hPhysicalMonitor, byte vcpCode, uint value)
+        {
+            if (hPhysicalMonitor == IntPtr.Zero)
+            {
+                return false;
+            }
+
+            try
+            {
+                return SetVCPFeature(hPhysicalMonitor, vcpCode, value);
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// 获取高级亮度信息的安全包装
+        /// </summary>
+        /// <param name="hPhysicalMonitor">物理显示器句柄</param>
+        /// <param name="minBrightness">最小亮度</param>
+        /// <param name="currentBrightness">当前亮度</param>
+        /// <param name="maxBrightness">最大亮度</param>
+        /// <returns>是否成功</returns>
+        public static bool TryGetMonitorBrightness(IntPtr hPhysicalMonitor, out uint minBrightness, out uint currentBrightness, out uint maxBrightness)
+        {
+            minBrightness = 0;
+            currentBrightness = 0;
+            maxBrightness = 0;
+
+            if (hPhysicalMonitor == IntPtr.Zero)
+            {
+                return false;
+            }
+
+            try
+            {
+                return GetMonitorBrightness(hPhysicalMonitor, out minBrightness, out currentBrightness, out maxBrightness);
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// 设置高级亮度的安全包装
+        /// </summary>
+        /// <param name="hPhysicalMonitor">物理显示器句柄</param>
+        /// <param name="brightness">亮度值</param>
+        /// <returns>是否成功</returns>
+        public static bool TrySetMonitorBrightness(IntPtr hPhysicalMonitor, uint brightness)
+        {
+            if (hPhysicalMonitor == IntPtr.Zero)
+            {
+                return false;
+            }
+
+            try
+            {
+                return SetMonitorBrightness(hPhysicalMonitor, brightness);
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// 检查 DDC/CI 连接的有效性
+        /// </summary>
+        /// <param name="hPhysicalMonitor">物理显示器句柄</param>
+        /// <returns>是否连接有效</returns>
+        public static bool ValidateDdcCiConnection(IntPtr hPhysicalMonitor)
+        {
+            if (hPhysicalMonitor == IntPtr.Zero)
+            {
+                return false;
+            }
+
+            // 尝试读取基本的 VCP 代码来验证连接
+            var testCodes = new byte[] { NativeConstants.VcpCodeBrightness, NativeConstants.VcpCodeNewControlValue, NativeConstants.VcpCodeVcpVersion };
+
+            foreach (var code in testCodes)
+            {
+                if (TryGetVCPFeature(hPhysicalMonitor, code, out _, out _))
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        /// <summary>
+        /// 获取显示器友好名称
+        /// </summary>
+        /// <param name="adapterId">适配器 ID</param>
+        /// <param name="targetId">目标 ID</param>
+        /// <returns>显示器友好名称，如果获取失败返回 null</returns>
+        public static unsafe string? GetMonitorFriendlyName(LUID adapterId, uint targetId)
+        {
+            try
+            {
+                var deviceName = new DISPLAYCONFIG_TARGET_DEVICE_NAME
+                {
+                    Header = new DISPLAYCONFIG_DEVICE_INFO_HEADER
+                    {
+                        Type = DisplayconfigDeviceInfoGetTargetName,
+                        Size = (uint)sizeof(DISPLAYCONFIG_TARGET_DEVICE_NAME),
+                        AdapterId = adapterId,
+                        Id = targetId,
+                    },
+                };
+
+                var result = DisplayConfigGetDeviceInfo(ref deviceName);
+                if (result == 0)
+                {
+                    return deviceName.GetMonitorFriendlyDeviceName();
+                }
+            }
+            catch
+            {
+                // 忽略错误
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// 通过枚举显示配置获取所有显示器友好名称
+        /// </summary>
+        /// <returns>设备路径到友好名称的映射</returns>
+        public static Dictionary<string, string> GetAllMonitorFriendlyNames()
+        {
+            var friendlyNames = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+
+            try
+            {
+                // 获取缓冲区大小
+                var result = GetDisplayConfigBufferSizes(QdcOnlyActivePaths, out uint pathCount, out uint modeCount);
+                if (result != 0)
+                {
+                    return friendlyNames;
+                }
+
+                // 分配缓冲区
+                var paths = new DISPLAYCONFIG_PATH_INFO[pathCount];
+                var modes = new DISPLAYCONFIG_MODE_INFO[modeCount];
+
+                // 查询显示配置
+                result = QueryDisplayConfig(QdcOnlyActivePaths, ref pathCount, paths, ref modeCount, modes, IntPtr.Zero);
+                if (result != 0)
+                {
+                    return friendlyNames;
+                }
+
+                // 获取每个路径的友好名称
+                for (int i = 0; i < pathCount; i++)
+                {
+                    var path = paths[i];
+                    var friendlyName = GetMonitorFriendlyName(path.TargetInfo.AdapterId, path.TargetInfo.Id);
+
+                    if (!string.IsNullOrEmpty(friendlyName))
+                    {
+                        // 使用适配器和目标 ID 作为键
+                        var key = $"{path.TargetInfo.AdapterId}_{path.TargetInfo.Id}";
+                        friendlyNames[key] = friendlyName;
+                    }
+                }
+            }
+            catch
+            {
+                // 忽略错误
+            }
+
+            return friendlyNames;
+        }
+
+        /// <summary>
+        /// 获取显示器的EDID硬件ID信息
+        /// </summary>
+        /// <param name="adapterId">适配器ID</param>
+        /// <param name="targetId">目标ID</param>
+        /// <returns>硬件ID字符串，格式为制造商代码+产品代码</returns>
+        public static unsafe string? GetMonitorHardwareId(LUID adapterId, uint targetId)
+        {
+            try
+            {
+                var deviceName = new DISPLAYCONFIG_TARGET_DEVICE_NAME
+                {
+                    Header = new DISPLAYCONFIG_DEVICE_INFO_HEADER
+                    {
+                        Type = DisplayconfigDeviceInfoGetTargetName,
+                        Size = (uint)sizeof(DISPLAYCONFIG_TARGET_DEVICE_NAME),
+                        AdapterId = adapterId,
+                        Id = targetId,
+                    },
+                };
+
+                var result = DisplayConfigGetDeviceInfo(ref deviceName);
+                if (result == 0)
+                {
+                    // 将制造商ID转换为3字符字符串
+                    var manufacturerId = deviceName.EdidManufactureId;
+                    var manufactureCode = ConvertManufactureIdToString(manufacturerId);
+
+                    // 将产品ID转换为4位十六进制字符串
+                    var productCode = deviceName.EdidProductCodeId.ToString("X4", System.Globalization.CultureInfo.InvariantCulture);
+
+                    var hardwareId = $"{manufactureCode}{productCode}";
+                    Logger.LogDebug($"GetMonitorHardwareId - ManufacturerId: 0x{manufacturerId:X4}, Code: '{manufactureCode}', ProductCode: '{productCode}', Result: '{hardwareId}'");
+
+                    return hardwareId;
+                }
+                else
+                {
+                    Logger.LogError($"GetMonitorHardwareId - DisplayConfigGetDeviceInfo failed with result: {result}");
+                }
+            }
+            catch
+            {
+                // 忽略错误
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// 将制造商ID转换为3字符制造商代码
+        /// </summary>
+        /// <param name="manufacturerId">制造商ID</param>
+        /// <returns>3字符制造商代码</returns>
+        private static string ConvertManufactureIdToString(ushort manufacturerId)
+        {
+            // EDID制造商ID需要先进行字节序交换
+            manufacturerId = (ushort)(((manufacturerId & 0xff00) >> 8) | ((manufacturerId & 0x00ff) << 8));
+
+            // 提取3个5位字符（每个字符是A-Z，其中A=1, B=2, ..., Z=26）
+            var char1 = (char)('A' - 1 + ((manufacturerId >> 0) & 0x1f));
+            var char2 = (char)('A' - 1 + ((manufacturerId >> 5) & 0x1f));
+            var char3 = (char)('A' - 1 + ((manufacturerId >> 10) & 0x1f));
+
+            // 按正确顺序组合字符
+            return $"{char3}{char2}{char1}";
+        }
+
+        /// <summary>
+        /// 获取所有显示器的完整信息，包括友好名称和硬件ID
+        /// </summary>
+        /// <returns>包含显示器信息的字典</returns>
+        public static Dictionary<string, MonitorDisplayInfo> GetAllMonitorDisplayInfo()
+        {
+            var monitorInfo = new Dictionary<string, MonitorDisplayInfo>(StringComparer.OrdinalIgnoreCase);
+
+            try
+            {
+                // 获取缓冲区大小
+                var result = GetDisplayConfigBufferSizes(QdcOnlyActivePaths, out uint pathCount, out uint modeCount);
+                if (result != 0)
+                {
+                    return monitorInfo;
+                }
+
+                // 分配缓冲区
+                var paths = new DISPLAYCONFIG_PATH_INFO[pathCount];
+                var modes = new DISPLAYCONFIG_MODE_INFO[modeCount];
+
+                // 查询显示配置
+                result = QueryDisplayConfig(QdcOnlyActivePaths, ref pathCount, paths, ref modeCount, modes, IntPtr.Zero);
+                if (result != 0)
+                {
+                    return monitorInfo;
+                }
+
+                // 获取每个路径的信息
+                for (int i = 0; i < pathCount; i++)
+                {
+                    var path = paths[i];
+                    var friendlyName = GetMonitorFriendlyName(path.TargetInfo.AdapterId, path.TargetInfo.Id);
+                    var hardwareId = GetMonitorHardwareId(path.TargetInfo.AdapterId, path.TargetInfo.Id);
+
+                    if (!string.IsNullOrEmpty(friendlyName) || !string.IsNullOrEmpty(hardwareId))
+                    {
+                        var key = $"{path.TargetInfo.AdapterId}_{path.TargetInfo.Id}";
+                        monitorInfo[key] = new MonitorDisplayInfo
+                        {
+                            FriendlyName = friendlyName ?? string.Empty,
+                            HardwareId = hardwareId ?? string.Empty,
+                            AdapterId = path.TargetInfo.AdapterId,
+                            TargetId = path.TargetInfo.Id,
+                        };
+                    }
+                }
+            }
+            catch
+            {
+                // 忽略错误
+            }
+
+            return monitorInfo;
+        }
+
+        /// <summary>
+        /// 获取所有显示设备信息（使用 EnumDisplayDevices API）
+        /// 与 Twinkle Tray 实现保持一致
+        /// </summary>
+        /// <returns>显示设备信息列表</returns>
+        public static unsafe List<DisplayDeviceInfo> GetAllDisplayDevices()
+        {
+            var devices = new List<DisplayDeviceInfo>();
+
+            try
+            {
+                // 枚举所有适配器
+                uint adapterIndex = 0;
+                var adapter = default(DISPLAY_DEVICE);
+                adapter.Cb = (uint)sizeof(DisplayDevice);
+
+                while (EnumDisplayDevices(null, adapterIndex, ref adapter, EddGetDeviceInterfaceName))
+                {
+                    // 跳过镜像驱动程序
+                    if ((adapter.StateFlags & DisplayDeviceMirroringDriver) != 0)
+                    {
+                        adapterIndex++;
+                        adapter = default(DISPLAY_DEVICE);
+                        adapter.Cb = (uint)sizeof(DisplayDevice);
+                        continue;
+                    }
+
+                    // 只处理已连接到桌面的适配器
+                    if ((adapter.StateFlags & DisplayDeviceAttachedToDesktop) != 0)
+                    {
+                        // 枚举该适配器上的所有显示器
+                        uint displayIndex = 0;
+                        var display = default(DISPLAY_DEVICE);
+                        display.Cb = (uint)sizeof(DisplayDevice);
+
+                        string adapterDeviceName = adapter.GetDeviceName();
+                        while (EnumDisplayDevices(adapterDeviceName, displayIndex, ref display, EddGetDeviceInterfaceName))
+                        {
+                            string displayDeviceID = display.GetDeviceID();
+
+                            // 只处理活动的显示器
+                            if ((display.StateFlags & DisplayDeviceAttachedToDesktop) != 0 &&
+                                !string.IsNullOrEmpty(displayDeviceID))
+                            {
+                                var deviceInfo = new DisplayDeviceInfo
+                                {
+                                    DeviceName = display.GetDeviceName(),
+                                    AdapterName = adapterDeviceName,
+                                    DeviceID = displayDeviceID,
+                                };
+
+                                // 提取 DeviceKey：移除 GUID 部分（#{...} 及之后的内容）
+                                // 例如：\\?\DISPLAY#GSM5C6D#5&1234&0&UID#{GUID} -> \\?\DISPLAY#GSM5C6D#5&1234&0&UID
+                                int guidIndex = deviceInfo.DeviceID.IndexOf("#{", StringComparison.Ordinal);
+                                if (guidIndex >= 0)
+                                {
+                                    deviceInfo.DeviceKey = deviceInfo.DeviceID.Substring(0, guidIndex);
+                                }
+                                else
+                                {
+                                    deviceInfo.DeviceKey = deviceInfo.DeviceID;
+                                }
+
+                                devices.Add(deviceInfo);
+
+                                Logger.LogDebug($"Found display device - Name: {deviceInfo.DeviceName}, Adapter: {deviceInfo.AdapterName}, DeviceKey: {deviceInfo.DeviceKey}");
+                            }
+
+                            displayIndex++;
+                            display = default(DISPLAY_DEVICE);
+                            display.Cb = (uint)sizeof(DisplayDevice);
+                        }
+                    }
+
+                    adapterIndex++;
+                    adapter = default(DISPLAY_DEVICE);
+                    adapter.Cb = (uint)sizeof(DisplayDevice);
+                }
+
+                Logger.LogInfo($"GetAllDisplayDevices found {devices.Count} display devices");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"GetAllDisplayDevices exception: {ex.Message}");
+            }
+
+            return devices;
+        }
+    }
+
+    /// <summary>
+    /// 显示器显示信息结构
+    /// </summary>
+    public struct MonitorDisplayInfo
+    {
+        public string FriendlyName { get; set; }
+
+        public string HardwareId { get; set; }
+
+        public LUID AdapterId { get; set; }
+
+        public uint TargetId { get; set; }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/DDC/MonitorDiscoveryHelper.cs

@@ -0,0 +1,274 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using ManagedCommon;
+using PowerDisplay.Core.Models;
+using static PowerDisplay.Native.NativeConstants;
+using static PowerDisplay.Native.PInvoke;
+
+using MONITORINFOEX = PowerDisplay.Native.MonitorInfoEx;
+using PHYSICAL_MONITOR = PowerDisplay.Native.PhysicalMonitor;
+using RECT = PowerDisplay.Native.Rect;
+
+namespace PowerDisplay.Native.DDC
+{
+    /// <summary>
+    /// Helper class for discovering and creating monitor objects
+    /// </summary>
+    public class MonitorDiscoveryHelper
+    {
+        private readonly VcpCodeResolver _vcpResolver;
+
+        public MonitorDiscoveryHelper(VcpCodeResolver vcpResolver)
+        {
+            _vcpResolver = vcpResolver;
+        }
+
+        /// <summary>
+        /// Get monitor device ID
+        /// </summary>
+        public unsafe string GetMonitorDeviceId(IntPtr hMonitor)
+        {
+            try
+            {
+                var monitorInfo = new MONITORINFOEX { CbSize = (uint)sizeof(MonitorInfoEx) };
+                if (GetMonitorInfo(hMonitor, ref monitorInfo))
+                {
+                    return monitorInfo.GetDeviceName() ?? string.Empty;
+                }
+            }
+            catch
+            {
+                // Silent failure
+            }
+
+            return string.Empty;
+        }
+
+        /// <summary>
+        /// Get physical monitors for a logical monitor
+        /// </summary>
+        internal PHYSICAL_MONITOR[]? GetPhysicalMonitors(IntPtr hMonitor)
+        {
+            try
+            {
+                Logger.LogDebug($"GetPhysicalMonitors: hMonitor=0x{hMonitor:X}");
+
+                if (!GetNumberOfPhysicalMonitorsFromHMONITOR(hMonitor, out uint numMonitors))
+                {
+                    Logger.LogWarning($"GetPhysicalMonitors: GetNumberOfPhysicalMonitorsFromHMONITOR failed for 0x{hMonitor:X}");
+                    return null;
+                }
+
+                Logger.LogDebug($"GetPhysicalMonitors: numMonitors={numMonitors}");
+                if (numMonitors == 0)
+                {
+                    Logger.LogWarning($"GetPhysicalMonitors: numMonitors is 0");
+                    return null;
+                }
+
+                var physicalMonitors = new PHYSICAL_MONITOR[numMonitors];
+                bool apiResult;
+                unsafe
+                {
+                    fixed (PHYSICAL_MONITOR* ptr = physicalMonitors)
+                    {
+                        apiResult = GetPhysicalMonitorsFromHMONITOR(hMonitor, numMonitors, ptr);
+                    }
+                }
+
+                Logger.LogDebug($"GetPhysicalMonitors: GetPhysicalMonitorsFromHMONITOR returned {apiResult}");
+
+                if (!apiResult)
+                {
+                    Logger.LogWarning($"GetPhysicalMonitors: GetPhysicalMonitorsFromHMONITOR failed");
+                    return null;
+                }
+
+                // Log each physical monitor
+                for (int i = 0; i < numMonitors; i++)
+                {
+                    string desc = physicalMonitors[i].GetDescription() ?? string.Empty;
+                    IntPtr handle = physicalMonitors[i].HPhysicalMonitor;
+                    Logger.LogDebug($"GetPhysicalMonitors: [{i}] Handle=0x{handle:X}, Desc='{desc}'");
+
+                    if (handle == IntPtr.Zero)
+                    {
+                        Logger.LogWarning($"GetPhysicalMonitors: Monitor [{i}] has NULL handle despite successful API call!");
+                    }
+                }
+
+                return physicalMonitors;
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"GetPhysicalMonitors: Exception: {ex.Message}");
+                return null;
+            }
+        }
+
+        /// <summary>
+        /// Create Monitor object from physical monitor
+        /// </summary>
+        internal Monitor? CreateMonitorFromPhysical(
+            PHYSICAL_MONITOR physicalMonitor,
+            string adapterName,
+            int index,
+            Dictionary<string, MonitorDisplayInfo> monitorDisplayInfo,
+            DisplayDeviceInfo? displayDevice)
+        {
+            try
+            {
+                // Get hardware ID and friendly name from the display info
+                string hardwareId = string.Empty;
+                string name = physicalMonitor.GetDescription() ?? string.Empty;
+
+                // Try to find matching monitor info
+                foreach (var kvp in monitorDisplayInfo.Values)
+                {
+                    if (!string.IsNullOrEmpty(kvp.HardwareId))
+                    {
+                        hardwareId = kvp.HardwareId;
+
+                        if (!string.IsNullOrEmpty(kvp.FriendlyName) && !kvp.FriendlyName.Contains("Generic"))
+                        {
+                            name = kvp.FriendlyName;
+                        }
+
+                        break;
+                    }
+                }
+
+                // Use stable device IDs from DisplayDeviceInfo
+                string deviceKey;
+                string monitorId;
+
+                if (displayDevice != null && !string.IsNullOrEmpty(displayDevice.DeviceKey))
+                {
+                    // Use stable device key from EnumDisplayDevices
+                    deviceKey = displayDevice.DeviceKey;
+                    monitorId = $"DDC_{deviceKey.Replace(@"\\?\", string.Empty, StringComparison.Ordinal).Replace("#", "_", StringComparison.Ordinal).Replace("&", "_", StringComparison.Ordinal)}";
+                }
+                else
+                {
+                    // Fallback: create device ID without handle in the key
+                    var baseDevice = adapterName.Replace(@"\\.\", string.Empty, StringComparison.Ordinal);
+                    deviceKey = $"{baseDevice}_{index}";
+                    monitorId = $"DDC_{deviceKey}";
+                }
+
+                // If still no good name, use default value
+                if (string.IsNullOrEmpty(name) || name.Contains("Generic") || name.Contains("PnP"))
+                {
+                    name = $"External Display {index + 1}";
+                }
+
+                // Get current brightness
+                var brightnessInfo = GetCurrentBrightness(physicalMonitor.HPhysicalMonitor);
+
+                var monitor = new Monitor
+                {
+                    Id = monitorId,
+                    HardwareId = hardwareId,
+                    Name = name.Trim(),
+                    Type = MonitorType.External,
+                    CurrentBrightness = brightnessInfo.IsValid ? brightnessInfo.ToPercentage() : 50,
+                    MinBrightness = 0,
+                    MaxBrightness = 100,
+                    IsAvailable = true,
+                    Handle = physicalMonitor.HPhysicalMonitor,
+                    DeviceKey = deviceKey,
+                    Capabilities = MonitorCapabilities.Brightness | MonitorCapabilities.DdcCi,
+                    ConnectionType = "External",
+                    CommunicationMethod = "DDC/CI",
+                    Manufacturer = ExtractManufacturer(name),
+                };
+
+                // Check contrast support
+                if (DdcCiNative.TryGetVCPFeature(physicalMonitor.HPhysicalMonitor, VcpCodeContrast, out _, out _))
+                {
+                    monitor.Capabilities |= MonitorCapabilities.Contrast;
+                }
+
+                // Check color temperature support (suppress logging for discovery)
+                var colorTempVcpCode = _vcpResolver.GetColorTemperatureVcpCode(monitorId, physicalMonitor.HPhysicalMonitor);
+                monitor.SupportsColorTemperature = colorTempVcpCode.HasValue;
+
+                // Check volume support
+                if (DdcCiNative.TryGetVCPFeature(physicalMonitor.HPhysicalMonitor, VcpCodeVolume, out _, out _))
+                {
+                    monitor.Capabilities |= MonitorCapabilities.Volume;
+                }
+
+                // Check high-level API support
+                if (DdcCiNative.TryGetMonitorBrightness(physicalMonitor.HPhysicalMonitor, out _, out _, out _))
+                {
+                    monitor.Capabilities |= MonitorCapabilities.HighLevel;
+                }
+
+                return monitor;
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"DDC: CreateMonitorFromPhysical exception: {ex.Message}");
+                return null;
+            }
+        }
+
+        /// <summary>
+        /// Get current brightness using VCP codes
+        /// </summary>
+        private BrightnessInfo GetCurrentBrightness(IntPtr handle)
+        {
+            // Try high-level API
+            if (DdcCiNative.TryGetMonitorBrightness(handle, out uint min, out uint current, out uint max))
+            {
+                return new BrightnessInfo((int)current, (int)min, (int)max);
+            }
+
+            // Try VCP codes
+            byte[] vcpCodes = { VcpCodeBrightness, VcpCodeBacklightControl, VcpCodeBacklightLevelWhite, VcpCodeContrast };
+            foreach (var code in vcpCodes)
+            {
+                if (DdcCiNative.TryGetVCPFeature(handle, code, out current, out max))
+                {
+                    return new BrightnessInfo((int)current, 0, (int)max);
+                }
+            }
+
+            return BrightnessInfo.Invalid;
+        }
+
+        /// <summary>
+        /// Extract manufacturer from name
+        /// </summary>
+        private string ExtractManufacturer(string name)
+        {
+            if (string.IsNullOrEmpty(name))
+            {
+                return "Unknown";
+            }
+
+            // Common manufacturer prefixes
+            var manufacturers = new[] { "DELL", "HP", "LG", "Samsung", "ASUS", "Acer", "BenQ", "AOC", "ViewSonic" };
+            var upperName = name.ToUpperInvariant();
+
+            foreach (var manufacturer in manufacturers)
+            {
+                if (upperName.Contains(manufacturer))
+                {
+                    return manufacturer;
+                }
+            }
+
+            // Return first word as manufacturer
+            var firstWord = name.Split(' ')[0];
+            return firstWord.Length > 2 ? firstWord : "Unknown";
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/DDC/PhysicalMonitorHandleManager.cs

@@ -0,0 +1,164 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using ManagedCommon;
+using PowerDisplay.Core.Models;
+using static PowerDisplay.Native.PInvoke;
+
+namespace PowerDisplay.Native.DDC
+{
+    /// <summary>
+    /// Manages physical monitor handles - reuse, cleanup, and validation
+    /// Twinkle Tray style handle management
+    /// </summary>
+    public partial class PhysicalMonitorHandleManager : IDisposable
+    {
+        // Twinkle Tray style mapping: deviceKey -> physical handle
+        private readonly Dictionary<string, IntPtr> _deviceKeyToHandleMap = new();
+        private bool _disposed;
+
+        /// <summary>
+        /// Get physical handle for monitor using stable deviceKey
+        /// </summary>
+        public IntPtr GetPhysicalHandle(Monitor monitor)
+        {
+            // Primary lookup: use stable deviceKey from EnumDisplayDevices
+            if (!string.IsNullOrEmpty(monitor.DeviceKey) &&
+                _deviceKeyToHandleMap.TryGetValue(monitor.DeviceKey, out var handle))
+            {
+                return handle;
+            }
+
+            // Fallback: use direct handle from monitor object
+            if (monitor.Handle != IntPtr.Zero)
+            {
+                return monitor.Handle;
+            }
+
+            return IntPtr.Zero;
+        }
+
+        /// <summary>
+        /// Try to reuse existing handle if valid, otherwise use new handle
+        /// Returns the handle to use and whether it was reused
+        /// </summary>
+        public (IntPtr Handle, bool WasReused) ReuseOrCreateHandle(string deviceKey, IntPtr newHandle)
+        {
+            if (string.IsNullOrEmpty(deviceKey))
+            {
+                return (newHandle, false);
+            }
+
+            // Try to reuse existing handle if it's still valid
+            if (_deviceKeyToHandleMap.TryGetValue(deviceKey, out var existingHandle) &&
+                existingHandle != IntPtr.Zero &&
+                DdcCiNative.ValidateDdcCiConnection(existingHandle))
+            {
+                // Destroy the newly created handle since we're using the old one
+                if (newHandle != existingHandle && newHandle != IntPtr.Zero)
+                {
+                    DestroyPhysicalMonitor(newHandle);
+                }
+
+                return (existingHandle, true);
+            }
+
+            return (newHandle, false);
+        }
+
+        /// <summary>
+        /// Update the handle mapping with new handles
+        /// </summary>
+        public void UpdateHandleMap(Dictionary<string, IntPtr> newHandleMap)
+        {
+            // Clean up unused handles before updating
+            CleanupUnusedHandles(newHandleMap);
+
+            // Update the device key map
+            _deviceKeyToHandleMap.Clear();
+            foreach (var kvp in newHandleMap)
+            {
+                _deviceKeyToHandleMap[kvp.Key] = kvp.Value;
+            }
+        }
+
+        /// <summary>
+        /// Clean up handles that are no longer in use
+        /// </summary>
+        private void CleanupUnusedHandles(Dictionary<string, IntPtr> newHandles)
+        {
+            if (_deviceKeyToHandleMap.Count == 0)
+            {
+                return;
+            }
+
+            var handlesToDestroy = new List<IntPtr>();
+
+            // Find handles that are in old map but not being reused
+            foreach (var oldMapping in _deviceKeyToHandleMap)
+            {
+                bool found = false;
+                foreach (var newMapping in newHandles)
+                {
+                    // If the same handle is being reused, don't destroy it
+                    if (oldMapping.Value == newMapping.Value)
+                    {
+                        found = true;
+                        break;
+                    }
+                }
+
+                if (!found && oldMapping.Value != IntPtr.Zero)
+                {
+                    handlesToDestroy.Add(oldMapping.Value);
+                }
+            }
+
+            // Destroy unused handles
+            foreach (var handle in handlesToDestroy)
+            {
+                try
+                {
+                    DestroyPhysicalMonitor(handle);
+                    Logger.LogDebug($"DDC: Cleaned up unused handle 0x{handle:X}");
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogWarning($"DDC: Failed to destroy handle 0x{handle:X}: {ex.Message}");
+                }
+            }
+        }
+
+        public void Dispose()
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            // Release all physical monitor handles
+            foreach (var handle in _deviceKeyToHandleMap.Values)
+            {
+                if (handle != IntPtr.Zero)
+                {
+                    try
+                    {
+                        DestroyPhysicalMonitor(handle);
+                        Logger.LogDebug($"Released physical monitor handle 0x{handle:X}");
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogWarning($"Failed to destroy physical monitor handle 0x{handle:X}: {ex.Message}");
+                    }
+                }
+            }
+
+            _deviceKeyToHandleMap.Clear();
+            _disposed = true;
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/DDC/VcpCodeResolver.cs

@@ -0,0 +1,124 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using ManagedCommon;
+using PowerDisplay.Core.Models;
+using PowerDisplay.Core.Utils;
+
+namespace PowerDisplay.Native.DDC
+{
+    /// <summary>
+    /// Resolves and caches VCP codes for monitor controls
+    /// Handles brightness, color temperature, and other VCP feature codes
+    /// </summary>
+    public class VcpCodeResolver
+    {
+        private readonly Dictionary<string, byte> _cachedCodes = new();
+
+        // VCP code priority order (for brightness control)
+        private static readonly byte[] BrightnessVcpCodes =
+        {
+            NativeConstants.VcpCodeBrightness,           // 0x10 - Standard brightness
+            NativeConstants.VcpCodeBacklightControl,    // 0x13 - Backlight control
+            NativeConstants.VcpCodeBacklightLevelWhite, // 0x6B - White backlight level
+            NativeConstants.VcpCodeContrast,             // 0x12 - Contrast as last resort
+        };
+
+        // VCP code priority order (for color temperature control)
+        private static readonly byte[] ColorTemperatureVcpCodes =
+        {
+            NativeConstants.VcpCodeColorTemperature,           // 0x0C - Standard color temperature
+            NativeConstants.VcpCodeColorTemperatureIncrement,  // 0x0B - Color temperature increment
+            NativeConstants.VcpCodeSelectColorPreset,          // 0x14 - Color preset selection
+            NativeConstants.VcpCodeGamma,                      // 0x72 - Gamma correction
+        };
+
+        /// <summary>
+        /// Get best VCP code for brightness control
+        /// </summary>
+        public byte? GetBrightnessVcpCode(string monitorId, IntPtr physicalHandle)
+        {
+            // Return cached best code if available
+            if (_cachedCodes.TryGetValue(monitorId, out var cachedCode))
+            {
+                return cachedCode;
+            }
+
+            // Find first working VCP code (highest priority)
+            foreach (var code in BrightnessVcpCodes)
+            {
+                if (DdcCiNative.TryGetVCPFeature(physicalHandle, code, out _, out _))
+                {
+                    // Cache and return the best (first working) code
+                    _cachedCodes[monitorId] = code;
+                    return code;
+                }
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Get best VCP code for color temperature control
+        /// </summary>
+        public byte? GetColorTemperatureVcpCode(string monitorId, IntPtr physicalHandle)
+        {
+            var cacheKey = $"{monitorId}_colortemp";
+
+            // Return cached best code if available
+            if (_cachedCodes.TryGetValue(cacheKey, out var cachedCode))
+            {
+                return cachedCode;
+            }
+
+            // Find first working VCP code (highest priority)
+            foreach (var code in ColorTemperatureVcpCodes)
+            {
+                if (DdcCiNative.TryGetVCPFeature(physicalHandle, code, out _, out _))
+                {
+                    // Cache and return the best (first working) code
+                    _cachedCodes[cacheKey] = code;
+                    return code;
+                }
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Convert Kelvin temperature to VCP value (uses unified converter)
+        /// </summary>
+        public uint ConvertKelvinToVcpValue(int kelvin, BrightnessInfo vcpRange)
+        {
+            return (uint)ColorTemperatureConverter.KelvinToVcp(kelvin, vcpRange.Maximum);
+        }
+
+        /// <summary>
+        /// Get current color temperature information
+        /// </summary>
+        public BrightnessInfo GetCurrentColorTemperature(IntPtr physicalHandle)
+        {
+            // Try different VCP codes to get color temperature
+            foreach (var code in ColorTemperatureVcpCodes)
+            {
+                if (DdcCiNative.TryGetVCPFeature(physicalHandle, code, out uint current, out uint max))
+                {
+                    return new BrightnessInfo((int)current, 0, (int)max);
+                }
+            }
+
+            return BrightnessInfo.Invalid;
+        }
+
+        /// <summary>
+        /// Clear all cached codes
+        /// </summary>
+        public void ClearCache()
+        {
+            _cachedCodes.Clear();
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/NativeConstants.cs

@@ -0,0 +1,304 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace PowerDisplay.Native
+{
+    /// <summary>
+    /// Windows API constant definitions
+    /// </summary>
+    public static class NativeConstants
+    {
+        /// <summary>
+        /// VCP code: Brightness (primary usage)
+        /// </summary>
+        public const byte VcpCodeBrightness = 0x10;
+
+        /// <summary>
+        /// VCP code: Contrast
+        /// </summary>
+        public const byte VcpCodeContrast = 0x12;
+
+        /// <summary>
+        /// VCP code: Backlight control (alternative brightness)
+        /// </summary>
+        public const byte VcpCodeBacklightControl = 0x13;
+
+        /// <summary>
+        /// VCP code: White backlight level
+        /// </summary>
+        public const byte VcpCodeBacklightLevelWhite = 0x6B;
+
+        /// <summary>
+        /// VCP code: Audio speaker volume
+        /// </summary>
+        public const byte VcpCodeVolume = 0x62;
+
+        /// <summary>
+        /// VCP code: Audio mute
+        /// </summary>
+        public const byte VcpCodeMute = 0x8D;
+
+        /// <summary>
+        /// VCP code: Color temperature request (主要色温控制)
+        /// </summary>
+        public const byte VcpCodeColorTemperature = 0x0C;
+
+        /// <summary>
+        /// VCP code: Color temperature increment (色温增量调节)
+        /// </summary>
+        public const byte VcpCodeColorTemperatureIncrement = 0x0B;
+
+        /// <summary>
+        /// VCP code: Gamma correction (Gamma调节)
+        /// </summary>
+        public const byte VcpCodeGamma = 0x72;
+
+        /// <summary>
+        /// VCP code: Select color preset (颜色预设选择)
+        /// </summary>
+        public const byte VcpCodeSelectColorPreset = 0x14;
+
+        /// <summary>
+        /// VCP code: VCP version
+        /// </summary>
+        public const byte VcpCodeVcpVersion = 0xDF;
+
+        /// <summary>
+        /// VCP code: New control value
+        /// </summary>
+        public const byte VcpCodeNewControlValue = 0x02;
+
+        /// <summary>
+        /// Display device attached to desktop
+        /// </summary>
+        public const uint DisplayDeviceAttachedToDesktop = 0x00000001;
+
+        /// <summary>
+        /// Multi-monitor primary display
+        /// </summary>
+        public const uint DisplayDeviceMultiDriver = 0x00000002;
+
+        /// <summary>
+        /// Primary device
+        /// </summary>
+        public const uint DisplayDevicePrimaryDevice = 0x00000004;
+
+        /// <summary>
+        /// Mirroring driver
+        /// </summary>
+        public const uint DisplayDeviceMirroringDriver = 0x00000008;
+
+        /// <summary>
+        /// VGA compatible
+        /// </summary>
+        public const uint DisplayDeviceVgaCompatible = 0x00000010;
+
+        /// <summary>
+        /// Removable device
+        /// </summary>
+        public const uint DisplayDeviceRemovable = 0x00000020;
+
+        /// <summary>
+        /// Get device interface name
+        /// </summary>
+        public const uint EddGetDeviceInterfaceName = 0x00000001;
+
+        /// <summary>
+        /// Primary monitor
+        /// </summary>
+        public const uint MonitorinfoFPrimary = 0x00000001;
+
+        /// <summary>
+        /// Query display config: only active paths
+        /// </summary>
+        public const uint QdcOnlyActivePaths = 0x00000002;
+
+        /// <summary>
+        /// Query display config: all paths
+        /// </summary>
+        public const uint QdcAllPaths = 0x00000001;
+
+        /// <summary>
+        /// Set display config: apply
+        /// </summary>
+        public const uint SdcApply = 0x00000080;
+
+        /// <summary>
+        /// Set display config: use supplied display config
+        /// </summary>
+        public const uint SdcUseSuppliedDisplayConfig = 0x00000020;
+
+        /// <summary>
+        /// Set display config: save to database
+        /// </summary>
+        public const uint SdcSaveToDatabase = 0x00000200;
+
+        /// <summary>
+        /// Set display config: topology supplied
+        /// </summary>
+        public const uint SdcTopologySupplied = 0x00000010;
+
+        /// <summary>
+        /// Set display config: allow path order changes
+        /// </summary>
+        public const uint SdcAllowPathOrderChanges = 0x00002000;
+
+        /// <summary>
+        /// Get target name
+        /// </summary>
+        public const uint DisplayconfigDeviceInfoGetTargetName = 1;
+
+        /// <summary>
+        /// Get SDR white level
+        /// </summary>
+        public const uint DisplayconfigDeviceInfoGetSdrWhiteLevel = 7;
+
+        /// <summary>
+        /// Get advanced color information
+        /// </summary>
+        public const uint DisplayconfigDeviceInfoGetAdvancedColorInfo = 9;
+
+        /// <summary>
+        /// Set SDR white level (custom)
+        /// </summary>
+        public const uint DisplayconfigDeviceInfoSetSdrWhiteLevel = 0xFFFFFFEE;
+
+        /// <summary>
+        /// Path active
+        /// </summary>
+        public const uint DisplayconfigPathActive = 0x00000001;
+
+        /// <summary>
+        /// Path mode index invalid
+        /// </summary>
+        public const uint DisplayconfigPathModeIdxInvalid = 0xFFFFFFFF;
+
+        /// <summary>
+        /// COM initialization: multithreaded
+        /// </summary>
+        public const uint CoinitMultithreaded = 0x0;
+
+        /// <summary>
+        /// RPC authentication level: connect
+        /// </summary>
+        public const uint RpcCAuthnLevelConnect = 2;
+
+        /// <summary>
+        /// RPC impersonation level: impersonate
+        /// </summary>
+        public const uint RpcCImpLevelImpersonate = 3;
+
+        /// <summary>
+        /// RPC authentication service: Win NT
+        /// </summary>
+        public const uint RpcCAuthnWinnt = 10;
+
+        /// <summary>
+        /// RPC authorization service: none
+        /// </summary>
+        public const uint RpcCAuthzNone = 0;
+
+        /// <summary>
+        /// RPC authentication level: call
+        /// </summary>
+        public const uint RpcCAuthnLevelCall = 3;
+
+        /// <summary>
+        /// EOAC: none
+        /// </summary>
+        public const uint EoacNone = 0;
+
+        /// <summary>
+        /// WMI flag: forward only
+        /// </summary>
+        public const long WbemFlagForwardOnly = 0x20;
+
+        /// <summary>
+        /// WMI flag: return immediately
+        /// </summary>
+        public const long WbemFlagReturnImmediately = 0x10;
+
+        /// <summary>
+        /// WMI flag: connect use max wait
+        /// </summary>
+        public const long WbemFlagConnectUseMaxWait = 0x80;
+
+        /// <summary>
+        /// Success
+        /// </summary>
+        public const int ErrorSuccess = 0;
+
+        /// <summary>
+        /// Insufficient buffer
+        /// </summary>
+        public const int ErrorInsufficientBuffer = 122;
+
+        /// <summary>
+        /// Invalid parameter
+        /// </summary>
+        public const int ErrorInvalidParameter = 87;
+
+        /// <summary>
+        /// Access denied
+        /// </summary>
+        public const int ErrorAccessDenied = 5;
+
+        /// <summary>
+        /// General failure
+        /// </summary>
+        public const int ErrorGenFailure = 31;
+
+        /// <summary>
+        /// Unsupported VCP code
+        /// </summary>
+        public const int ErrorGraphicsDdcciVcpNotSupported = -1071243251;
+
+        /// <summary>
+        /// Infinite wait
+        /// </summary>
+        public const uint Infinite = 0xFFFFFFFF;
+
+        /// <summary>
+        /// User message
+        /// </summary>
+        public const uint WmUser = 0x0400;
+
+        /// <summary>
+        /// Output technology: HDMI
+        /// </summary>
+        public const uint DisplayconfigOutputTechnologyHdmi = 5;
+
+        /// <summary>
+        /// Output technology: DVI
+        /// </summary>
+        public const uint DisplayconfigOutputTechnologyDvi = 4;
+
+        /// <summary>
+        /// Output technology: DisplayPort
+        /// </summary>
+        public const uint DisplayconfigOutputTechnologyDisplayportExternal = 6;
+
+        /// <summary>
+        /// Output technology: internal
+        /// </summary>
+        public const uint DisplayconfigOutputTechnologyInternal = 0x80000000;
+
+        /// <summary>
+        /// HDR minimum SDR white level (nits)
+        /// </summary>
+        public const int HdrMinSdrWhiteLevel = 80;
+
+        /// <summary>
+        /// HDR maximum SDR white level (nits)
+        /// </summary>
+        public const int HdrMaxSdrWhiteLevel = 480;
+
+        /// <summary>
+        /// SDR white level conversion factor
+        /// </summary>
+        public const int SdrWhiteLevelFactor = 80;
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/NativeDelegates.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+// 类型别名，兼容 Windows API 命名约定
+using RECT = PowerDisplay.Native.Rect;
+
+namespace PowerDisplay.Native;
+
+/// <summary>
+/// 委托类型定义
+/// </summary>
+public static class NativeDelegates
+{
+    /// <summary>
+    /// 显示器枚举过程委托
+    /// </summary>
+    /// <param name="hMonitor">显示器句柄</param>
+    /// <param name="hdcMonitor">显示器 DC</param>
+    /// <param name="lprcMonitor">显示器矩形指针</param>
+    /// <param name="dwData">用户数据</param>
+    /// <returns>继续枚举返回 true</returns>
+    [UnmanagedFunctionPointer(CallingConvention.StdCall)]
+    public delegate bool MonitorEnumProc(IntPtr hMonitor, IntPtr hdcMonitor, IntPtr lprcMonitor, IntPtr dwData);
+
+    /// <summary>
+    /// 线程启动例程委托
+    /// </summary>
+    /// <param name="lpParameter">线程参数</param>
+    /// <returns>线程退出代码</returns>
+    public delegate uint ThreadStartRoutine(IntPtr lpParameter);
+}

src/modules/powerdisplay/PowerDisplay/Native/NativeStructures.cs

@@ -0,0 +1,532 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+#pragma warning disable SA1649 // File name should match first type name - Multiple related P/Invoke structures
+
+namespace PowerDisplay.Native
+{
+    /// <summary>
+    /// Physical monitor structure for DDC/CI
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public unsafe struct PhysicalMonitor
+    {
+        /// <summary>
+        /// Physical monitor handle
+        /// </summary>
+        public IntPtr HPhysicalMonitor;
+
+        /// <summary>
+        /// Physical monitor description string - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort SzPhysicalMonitorDescription[128];
+
+        /// <summary>
+        /// Helper method to get description as string
+        /// </summary>
+        public readonly string GetDescription()
+        {
+            fixed (ushort* ptr = SzPhysicalMonitorDescription)
+            {
+                return new string((char*)ptr);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Rectangle structure
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct Rect
+    {
+        public int Left;
+        public int Top;
+        public int Right;
+        public int Bottom;
+
+        public int Width => Right - Left;
+
+        public int Height => Bottom - Top;
+
+        public Rect(int left, int top, int right, int bottom)
+        {
+            Left = left;
+            Top = top;
+            Right = right;
+            Bottom = bottom;
+        }
+    }
+
+    /// <summary>
+    /// Monitor information extended structure
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public unsafe struct MonitorInfoEx
+    {
+        /// <summary>
+        /// Structure size
+        /// </summary>
+        public uint CbSize;
+
+        /// <summary>
+        /// Monitor rectangle area
+        /// </summary>
+        public Rect RcMonitor;
+
+        /// <summary>
+        /// Work area rectangle
+        /// </summary>
+        public Rect RcWork;
+
+        /// <summary>
+        /// Flags
+        /// </summary>
+        public uint DwFlags;
+
+        /// <summary>
+        /// Device name (e.g., "\\.\DISPLAY1") - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort SzDevice[32];
+
+        /// <summary>
+        /// Helper property to get device name as string
+        /// </summary>
+        public readonly string GetDeviceName()
+        {
+            fixed (ushort* ptr = SzDevice)
+            {
+                return new string((char*)ptr);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Display device structure
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public unsafe struct DisplayDevice
+    {
+        /// <summary>
+        /// Structure size
+        /// </summary>
+        public uint Cb;
+
+        /// <summary>
+        /// Device name (e.g., "\\.\DISPLAY1\Monitor0") - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort DeviceName[32];
+
+        /// <summary>
+        /// Device description string - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort DeviceString[128];
+
+        /// <summary>
+        /// Status flags
+        /// </summary>
+        public uint StateFlags;
+
+        /// <summary>
+        /// Device ID - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort DeviceID[128];
+
+        /// <summary>
+        /// Registry device key - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort DeviceKey[128];
+
+        /// <summary>
+        /// Helper method to get device name as string
+        /// </summary>
+        public readonly string GetDeviceName()
+        {
+            fixed (ushort* ptr = DeviceName)
+            {
+                return new string((char*)ptr);
+            }
+        }
+
+        /// <summary>
+        /// Helper method to get device string as string
+        /// </summary>
+        public readonly string GetDeviceString()
+        {
+            fixed (ushort* ptr = DeviceString)
+            {
+                return new string((char*)ptr);
+            }
+        }
+
+        /// <summary>
+        /// Helper method to get device ID as string
+        /// </summary>
+        public readonly string GetDeviceID()
+        {
+            fixed (ushort* ptr = DeviceID)
+            {
+                return new string((char*)ptr);
+            }
+        }
+
+        /// <summary>
+        /// Helper method to get device key as string
+        /// </summary>
+        public readonly string GetDeviceKey()
+        {
+            fixed (ushort* ptr = DeviceKey)
+            {
+                return new string((char*)ptr);
+            }
+        }
+    }
+
+    /// <summary>
+    /// LUID (Locally Unique Identifier) structure
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct Luid
+    {
+        public uint LowPart;
+        public int HighPart;
+
+        public override string ToString()
+        {
+            return $"{HighPart:X8}:{LowPart:X8}";
+        }
+    }
+
+    /// <summary>
+    /// Display configuration path information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_PATH_INFO
+    {
+        public DISPLAYCONFIG_PATH_SOURCE_INFO SourceInfo;
+        public DISPLAYCONFIG_PATH_TARGET_INFO TargetInfo;
+        public uint Flags;
+    }
+
+    /// <summary>
+    /// Display configuration path source information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_PATH_SOURCE_INFO
+    {
+        public Luid AdapterId;
+        public uint Id;
+        public uint ModeInfoIdx;
+        public uint StatusFlags;
+    }
+
+    /// <summary>
+    /// Display configuration path target information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_PATH_TARGET_INFO
+    {
+        public Luid AdapterId;
+        public uint Id;
+        public uint ModeInfoIdx;
+        public uint OutputTechnology;
+        public uint Rotation;
+        public uint Scaling;
+        public DISPLAYCONFIG_RATIONAL RefreshRate;
+        public uint ScanLineOrdering;
+        public bool TargetAvailable;
+        public uint StatusFlags;
+    }
+
+    /// <summary>
+    /// Display configuration rational number
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_RATIONAL
+    {
+        public uint Numerator;
+        public uint Denominator;
+    }
+
+    /// <summary>
+    /// Display configuration mode information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_MODE_INFO
+    {
+        public uint InfoType;
+        public uint Id;
+        public Luid AdapterId;
+        public DISPLAYCONFIG_MODE_INFO_UNION ModeInfo;
+    }
+
+    /// <summary>
+    /// Display configuration mode information union
+    /// </summary>
+    [StructLayout(LayoutKind.Explicit)]
+    public struct DISPLAYCONFIG_MODE_INFO_UNION
+    {
+        [FieldOffset(0)]
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("StyleCop.CSharp.NamingRules", "SA1307:Accessible fields should begin with upper-case letter", Justification = "Native API structure field")]
+        public DISPLAYCONFIG_TARGET_MODE targetMode;
+
+        [FieldOffset(0)]
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("StyleCop.CSharp.NamingRules", "SA1307:Accessible fields should begin with upper-case letter", Justification = "Native API structure field")]
+        public DISPLAYCONFIG_SOURCE_MODE sourceMode;
+    }
+
+    /// <summary>
+    /// Display configuration target mode
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_TARGET_MODE
+    {
+        public DISPLAYCONFIG_VIDEO_SIGNAL_INFO TargetVideoSignalInfo;
+    }
+
+    /// <summary>
+    /// Display configuration source mode
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_SOURCE_MODE
+    {
+        public uint Width;
+        public uint Height;
+        public uint PixelFormat;
+        public DISPLAYCONFIG_POINT Position;
+    }
+
+    /// <summary>
+    /// Display configuration point
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_POINT
+    {
+        public int X;
+        public int Y;
+    }
+
+    /// <summary>
+    /// Display configuration video signal information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_VIDEO_SIGNAL_INFO
+    {
+        public ulong PixelRate;
+        public DISPLAYCONFIG_RATIONAL HSyncFreq;
+        public DISPLAYCONFIG_RATIONAL VSyncFreq;
+        public DISPLAYCONFIG_2DREGION ActiveSize;
+        public DISPLAYCONFIG_2DREGION TotalSize;
+        public uint VideoStandard;
+        public uint ScanLineOrdering;
+    }
+
+    /// <summary>
+    /// Display configuration 2D region
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_2DREGION
+    {
+        public uint Cx;
+        public uint Cy;
+    }
+
+    /// <summary>
+    /// Display configuration device information header
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_DEVICE_INFO_HEADER
+    {
+        public uint Type;
+        public uint Size;
+        public Luid AdapterId;
+        public uint Id;
+    }
+
+    /// <summary>
+    /// Display configuration target device name
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public unsafe struct DISPLAYCONFIG_TARGET_DEVICE_NAME
+    {
+        public DISPLAYCONFIG_DEVICE_INFO_HEADER Header;
+        public uint Flags;
+        public uint OutputTechnology;
+        public ushort EdidManufactureId;
+        public ushort EdidProductCodeId;
+        public uint ConnectorInstance;
+
+        /// <summary>
+        /// Monitor friendly name - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort MonitorFriendlyDeviceName[64];
+
+        /// <summary>
+        /// Monitor device path - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort MonitorDevicePath[128];
+
+        /// <summary>
+        /// Helper method to get monitor friendly name as string
+        /// </summary>
+        public readonly string GetMonitorFriendlyDeviceName()
+        {
+            fixed (ushort* ptr = MonitorFriendlyDeviceName)
+            {
+                return new string((char*)ptr);
+            }
+        }
+
+        /// <summary>
+        /// Helper method to get monitor device path as string
+        /// </summary>
+        public readonly string GetMonitorDevicePath()
+        {
+            fixed (ushort* ptr = MonitorDevicePath)
+            {
+                return new string((char*)ptr);
+            }
+        }
+    }
+
+    /// <summary>
+    /// Display configuration SDR white level
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_SDR_WHITE_LEVEL
+    {
+        public DISPLAYCONFIG_DEVICE_INFO_HEADER Header;
+        public uint SDRWhiteLevel;
+    }
+
+    /// <summary>
+    /// Display configuration advanced color information
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_GET_ADVANCED_COLOR_INFO
+    {
+        public DISPLAYCONFIG_DEVICE_INFO_HEADER Header;
+        public uint AdvancedColorSupported;
+        public uint AdvancedColorEnabled;
+        public uint BitsPerColorChannel;
+        public uint ColorEncoding;
+        public uint FormatSupport;
+    }
+
+    /// <summary>
+    /// Custom structure for setting SDR white level
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DISPLAYCONFIG_SET_SDR_WHITE_LEVEL
+    {
+        public DISPLAYCONFIG_DEVICE_INFO_HEADER Header;
+        public uint SDRWhiteLevel;
+        public byte FinalValue;
+    }
+
+    /// <summary>
+    /// Point structure
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct POINT
+    {
+        public int X;
+        public int Y;
+
+        public POINT(int x, int y)
+        {
+            this.X = x;
+            this.Y = y;
+        }
+    }
+
+    /// <summary>
+    /// Notify icon data structure (for system tray)
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public unsafe struct NOTIFYICONDATA
+    {
+        public uint CbSize;
+        public IntPtr HWnd;
+        public uint UID;
+        public uint UFlags;
+        public uint UCallbackMessage;
+        public IntPtr HIcon;
+
+        /// <summary>
+        /// Tooltip text - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort SzTip[128];
+
+        public uint DwState;
+        public uint DwStateMask;
+
+        /// <summary>
+        /// Info balloon text - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort SzInfo[256];
+
+        public uint UTimeout;
+
+        /// <summary>
+        /// Info balloon title - fixed buffer for LibraryImport compatibility
+        /// </summary>
+        public fixed ushort SzInfoTitle[64];
+
+        public uint DwInfoFlags;
+
+        /// <summary>
+        /// Helper method to set tooltip text
+        /// </summary>
+        public void SetTip(string tip)
+        {
+            fixed (ushort* ptr = SzTip)
+            {
+                int length = Math.Min(tip.Length, 127);
+                for (int i = 0; i < length; i++)
+                {
+                    ptr[i] = tip[i];
+                }
+
+                ptr[length] = 0; // Null terminator
+            }
+        }
+
+        /// <summary>
+        /// Helper method to set info balloon text
+        /// </summary>
+        public void SetInfo(string info)
+        {
+            fixed (ushort* ptr = SzInfo)
+            {
+                int length = Math.Min(info.Length, 255);
+                for (int i = 0; i < length; i++)
+                {
+                    ptr[i] = info[i];
+                }
+
+                ptr[length] = 0; // Null terminator
+            }
+        }
+
+        /// <summary>
+        /// Helper method to set info balloon title
+        /// </summary>
+        public void SetInfoTitle(string title)
+        {
+            fixed (ushort* ptr = SzInfoTitle)
+            {
+                int length = Math.Min(title.Length, 63);
+                for (int i = 0; i < length; i++)
+                {
+                    ptr[i] = title[i];
+                }
+
+                ptr[length] = 0; // Null terminator
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/PInvoke.cs

@@ -0,0 +1,275 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace PowerDisplay.Native
+{
+    /// <summary>
+    /// P/Invoke declarations using LibraryImport source generator
+    /// </summary>
+    internal static partial class PInvoke
+    {
+        // ==================== User32.dll - Window Management ====================
+        // GetWindowLong: On 64-bit use GetWindowLongPtrW, on 32-bit use GetWindowLongW
+#if WIN64
+        [LibraryImport("user32.dll", EntryPoint = "GetWindowLongPtrW")]
+        internal static partial IntPtr GetWindowLong(IntPtr hWnd, int nIndex);
+#else
+        [LibraryImport("user32.dll", EntryPoint = "GetWindowLongW")]
+        internal static partial int GetWindowLong(IntPtr hWnd, int nIndex);
+#endif
+
+        // SetWindowLong: On 64-bit use SetWindowLongPtrW, on 32-bit use SetWindowLongW
+#if WIN64
+        [LibraryImport("user32.dll", EntryPoint = "SetWindowLongPtrW")]
+        internal static partial IntPtr SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
+#else
+        [LibraryImport("user32.dll", EntryPoint = "SetWindowLongW")]
+        internal static partial int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
+#endif
+
+        // SetWindowLongPtr: Always uses the Ptr variant (64-bit)
+        [LibraryImport("user32.dll", EntryPoint = "SetWindowLongPtrW")]
+        internal static partial IntPtr SetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SetWindowPos(
+            IntPtr hWnd,
+            IntPtr hWndInsertAfter,
+            int x,
+            int y,
+            int cx,
+            int cy,
+            uint uFlags);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool ShowWindow(IntPtr hWnd, int nCmdShow);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SetForegroundWindow(IntPtr hWnd);
+
+        // ==================== User32.dll - Window Creation and Messaging ====================
+        [LibraryImport("user32.dll", EntryPoint = "CreateWindowExW", StringMarshalling = StringMarshalling.Utf16)]
+        internal static partial IntPtr CreateWindowEx(
+            uint dwExStyle,
+            [MarshalAs(UnmanagedType.LPWStr)] string lpClassName,
+            [MarshalAs(UnmanagedType.LPWStr)] string lpWindowName,
+            uint dwStyle,
+            int x,
+            int y,
+            int nWidth,
+            int nHeight,
+            IntPtr hWndParent,
+            IntPtr hMenu,
+            IntPtr hInstance,
+            IntPtr lpParam);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool DestroyWindow(IntPtr hWnd);
+
+        [LibraryImport("user32.dll", EntryPoint = "DefWindowProcW")]
+        internal static partial IntPtr DefWindowProc(IntPtr hWnd, uint uMsg, IntPtr wParam, IntPtr lParam);
+
+        [LibraryImport("user32.dll")]
+        internal static partial IntPtr LoadIcon(IntPtr hInstance, IntPtr lpIconName);
+
+        [LibraryImport("user32.dll", EntryPoint = "RegisterWindowMessageW", StringMarshalling = StringMarshalling.Utf16)]
+        internal static partial uint RegisterWindowMessage([MarshalAs(UnmanagedType.LPWStr)] string lpString);
+
+        // ==================== User32.dll - Menu Functions ====================
+        [LibraryImport("user32.dll")]
+        internal static partial IntPtr CreatePopupMenu();
+
+        [LibraryImport("user32.dll", EntryPoint = "AppendMenuW", StringMarshalling = StringMarshalling.Utf16)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool AppendMenu(
+            IntPtr hMenu,
+            uint uFlags,
+            uint uIDNewItem,
+            [MarshalAs(UnmanagedType.LPWStr)] string lpNewItem);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool DestroyMenu(IntPtr hMenu);
+
+        [LibraryImport("user32.dll")]
+        internal static partial int TrackPopupMenu(
+            IntPtr hMenu,
+            uint uFlags,
+            int x,
+            int y,
+            int nReserved,
+            IntPtr hWnd,
+            IntPtr prcRect);
+
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetCursorPos(out POINT lpPoint);
+
+        // ==================== User32.dll - Display Configuration ====================
+        [LibraryImport("user32.dll")]
+        internal static partial int GetDisplayConfigBufferSizes(
+            uint flags,
+            out uint numPathArrayElements,
+            out uint numModeInfoArrayElements);
+
+        // With DisableRuntimeMarshalling, LibraryImport can handle struct arrays
+        [LibraryImport("user32.dll")]
+        internal static partial int QueryDisplayConfig(
+            uint flags,
+            ref uint numPathArrayElements,
+            [Out] DISPLAYCONFIG_PATH_INFO[] pathArray,
+            ref uint numModeInfoArrayElements,
+            [Out] DISPLAYCONFIG_MODE_INFO[] modeInfoArray,
+            IntPtr currentTopologyId);
+
+        [LibraryImport("user32.dll")]
+        internal static partial int DisplayConfigGetDeviceInfo(
+            ref DISPLAYCONFIG_TARGET_DEVICE_NAME deviceName);
+
+        // ==================== User32.dll - Monitor Enumeration ====================
+        [LibraryImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool EnumDisplayMonitors(
+            IntPtr hdc,
+            IntPtr lprcClip,
+            NativeDelegates.MonitorEnumProc lpfnEnum,
+            IntPtr dwData);
+
+        [LibraryImport("user32.dll", EntryPoint = "GetMonitorInfoW", StringMarshalling = StringMarshalling.Utf16)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetMonitorInfo(
+            IntPtr hMonitor,
+            ref MonitorInfoEx lpmi);
+
+        [LibraryImport("user32.dll", EntryPoint = "EnumDisplayDevicesW", StringMarshalling = StringMarshalling.Utf16)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool EnumDisplayDevices(
+            [MarshalAs(UnmanagedType.LPWStr)] string? lpDevice,
+            uint iDevNum,
+            ref DisplayDevice lpDisplayDevice,
+            uint dwFlags);
+
+        [LibraryImport("user32.dll")]
+        internal static partial IntPtr MonitorFromWindow(
+            IntPtr hwnd,
+            uint dwFlags);
+
+        [LibraryImport("user32.dll")]
+        internal static partial IntPtr MonitorFromPoint(
+            POINT pt,
+            uint dwFlags);
+
+        // ==================== Shell32.dll - Tray Icon ====================
+        [LibraryImport("shell32.dll", EntryPoint = "Shell_NotifyIconW", StringMarshalling = StringMarshalling.Utf16)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool Shell_NotifyIcon(
+            uint dwMessage,
+            ref NOTIFYICONDATA lpData);
+
+        // ==================== Dxva2.dll - DDC/CI Monitor Control ====================
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetNumberOfPhysicalMonitorsFromHMONITOR(
+            IntPtr hMonitor,
+            out uint pdwNumberOfPhysicalMonitors);
+
+        // Use unsafe pointer to avoid ArraySubType limitation
+        [LibraryImport("Dxva2.dll", StringMarshalling = StringMarshalling.Utf16)]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static unsafe partial bool GetPhysicalMonitorsFromHMONITOR(
+            IntPtr hMonitor,
+            uint dwPhysicalMonitorArraySize,
+            PhysicalMonitor* pPhysicalMonitorArray);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool DestroyPhysicalMonitor(IntPtr hMonitor);
+
+        // Use unsafe pointer to avoid LPArray limitation
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static unsafe partial bool DestroyPhysicalMonitors(
+            uint dwPhysicalMonitorArraySize,
+            PhysicalMonitor* pPhysicalMonitorArray);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetVCPFeatureAndVCPFeatureReply(
+            IntPtr hPhysicalMonitor,
+            byte bVCPCode,
+            IntPtr pvct,
+            out uint pdwCurrentValue,
+            out uint pdwMaximumValue);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SetVCPFeature(
+            IntPtr hPhysicalMonitor,
+            byte bVCPCode,
+            uint dwNewValue);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SaveCurrentSettings(IntPtr hPhysicalMonitor);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetCapabilitiesStringLength(
+            IntPtr hPhysicalMonitor,
+            out uint pdwCapabilitiesStringLengthInCharacters);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool CapabilitiesRequestAndCapabilitiesReply(
+            IntPtr hPhysicalMonitor,
+            IntPtr pszASCIICapabilitiesString,
+            uint dwCapabilitiesStringLengthInCharacters);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetMonitorBrightness(
+            IntPtr hPhysicalMonitor,
+            out uint pdwMinimumBrightness,
+            out uint pdwCurrentBrightness,
+            out uint pdwMaximumBrightness);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SetMonitorBrightness(
+            IntPtr hPhysicalMonitor,
+            uint dwNewBrightness);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetMonitorContrast(
+            IntPtr hPhysicalMonitor,
+            out uint pdwMinimumContrast,
+            out uint pdwCurrentContrast,
+            out uint pdwMaximumContrast);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool SetMonitorContrast(
+            IntPtr hPhysicalMonitor,
+            uint dwNewContrast);
+
+        [LibraryImport("Dxva2.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        internal static partial bool GetMonitorCapabilities(
+            IntPtr hPhysicalMonitor,
+            out uint pdwMonitorCapabilities,
+            out uint pdwSupportedColorTemperatures);
+
+        // ==================== Kernel32.dll ====================
+        [LibraryImport("kernel32.dll")]
+        internal static partial uint GetLastError();
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/WMI/WmiController.cs

@@ -0,0 +1,450 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+using PowerDisplay.Core.Interfaces;
+using PowerDisplay.Core.Models;
+using WmiLight;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay.Native.WMI
+{
+    /// <summary>
+    /// WMI monitor controller for controlling internal laptop displays.
+    /// Rewritten to use WmiLight library for Native AOT compatibility.
+    /// </summary>
+    public partial class WmiController : IMonitorController, IDisposable
+    {
+        private const string WmiNamespace = @"root\WMI";
+        private const string BrightnessQueryClass = "WmiMonitorBrightness";
+        private const string BrightnessMethodClass = "WmiMonitorBrightnessMethods";
+        private const string MonitorIdClass = "WmiMonitorID";
+
+        private bool _disposed;
+
+        public string Name => "WMI Monitor Controller (WmiLight)";
+
+        public MonitorType SupportedType => MonitorType.Internal;
+
+        /// <summary>
+        /// Check if the specified monitor can be controlled
+        /// </summary>
+        public async Task<bool> CanControlMonitorAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            if (monitor.Type != MonitorType.Internal)
+            {
+                return false;
+            }
+
+            return await Task.Run(
+                () =>
+                {
+                    try
+                    {
+                        using var connection = new WmiConnection(WmiNamespace);
+                        var query = $"SELECT * FROM {BrightnessQueryClass}";
+                        var results = connection.CreateQuery(query).ToList();
+                        return results.Count > 0;
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogWarning($"WMI CanControlMonitor check failed: {ex.Message}");
+                        return false;
+                    }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get monitor brightness
+        /// </summary>
+        public async Task<BrightnessInfo> GetBrightnessAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                    try
+                    {
+                        using var connection = new WmiConnection(WmiNamespace);
+                        var query = $"SELECT CurrentBrightness FROM {BrightnessQueryClass}";
+                        var results = connection.CreateQuery(query);
+
+                        foreach (var obj in results)
+                        {
+                            var currentBrightness = obj.GetPropertyValue<byte>("CurrentBrightness");
+                            return new BrightnessInfo(currentBrightness, 0, 100);
+                        }
+                    }
+                    catch (WmiException ex)
+                    {
+                        Logger.LogWarning($"WMI GetBrightness failed: {ex.Message} (HResult: 0x{ex.HResult:X})");
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogWarning($"WMI GetBrightness failed: {ex.Message}");
+                    }
+
+                    return BrightnessInfo.Invalid;
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Set monitor brightness
+        /// </summary>
+        public async Task<MonitorOperationResult> SetBrightnessAsync(Monitor monitor, int brightness, CancellationToken cancellationToken = default)
+        {
+            // Validate brightness range
+            brightness = Math.Clamp(brightness, 0, 100);
+
+            return await Task.Run(
+                () =>
+                {
+                    try
+                    {
+                    using var connection = new WmiConnection(WmiNamespace);
+                    var query = $"SELECT * FROM {BrightnessMethodClass}";
+                    var results = connection.CreateQuery(query);
+
+                    foreach (var obj in results)
+                    {
+                        // Call WmiSetBrightness method
+                        // Parameters: Timeout (uint32), Brightness (byte)
+                        using (WmiMethod method = obj.GetMethod("WmiSetBrightness"))
+                        using (WmiMethodParameters inParams = method.CreateInParameters())
+                        {
+                            inParams.SetPropertyValue("Timeout", 0u);
+                            inParams.SetPropertyValue("Brightness", (byte)brightness);
+
+                            uint result = obj.ExecuteMethod<uint>(
+                                method,
+                                inParams,
+                                out WmiMethodParameters outParams);
+
+                            // Check return value (0 indicates success)
+                            if (result == 0)
+                            {
+                                return MonitorOperationResult.Success();
+                            }
+                            else
+                            {
+                                return MonitorOperationResult.Failure($"WMI method returned error code: {result}", (int)result);
+                            }
+                        }
+                    }
+
+                    return MonitorOperationResult.Failure("No WMI brightness methods found");
+                }
+                catch (UnauthorizedAccessException)
+                {
+                    return MonitorOperationResult.Failure("Access denied. Administrator privileges may be required.", 5);
+                }
+                catch (WmiException ex)
+                {
+                    return MonitorOperationResult.Failure($"WMI error: {ex.Message}", ex.HResult);
+                }
+                catch (Exception ex)
+                {
+                    return MonitorOperationResult.Failure($"Unexpected error: {ex.Message}");
+                }
+            },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Discover supported monitors
+        /// </summary>
+        public async Task<IEnumerable<Monitor>> DiscoverMonitorsAsync(CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                var monitors = new List<Monitor>();
+
+                try
+                {
+                    using var connection = new WmiConnection(WmiNamespace);
+
+                    // First check if WMI brightness support is available
+                    var brightnessQuery = $"SELECT * FROM {BrightnessQueryClass}";
+                    var brightnessResults = connection.CreateQuery(brightnessQuery).ToList();
+
+                    if (brightnessResults.Count == 0)
+                    {
+                        return monitors;
+                    }
+
+                    // Get monitor information
+                    var idQuery = $"SELECT * FROM {MonitorIdClass}";
+                    var idResults = connection.CreateQuery(idQuery).ToList();
+
+                    var monitorInfos = new Dictionary<string, (string Name, string InstanceName)>();
+
+                    foreach (var obj in idResults)
+                    {
+                        try
+                        {
+                            var instanceName = obj.GetPropertyValue<string>("InstanceName") ?? string.Empty;
+                            var userFriendlyName = GetUserFriendlyName(obj) ?? "Internal Display";
+
+                            if (!string.IsNullOrEmpty(instanceName))
+                            {
+                                monitorInfos[instanceName] = (userFriendlyName, instanceName);
+                            }
+                        }
+                        catch (Exception ex)
+                        {
+                            // Skip problematic entries
+                            Logger.LogDebug($"Failed to parse WMI monitor info: {ex.Message}");
+                        }
+                    }
+
+                    // Create monitor objects for each supported brightness instance
+                    foreach (var obj in brightnessResults)
+                    {
+                        try
+                        {
+                            var instanceName = obj.GetPropertyValue<string>("InstanceName") ?? string.Empty;
+                            var currentBrightness = obj.GetPropertyValue<byte>("CurrentBrightness");
+
+                            var name = "Internal Display";
+                            if (monitorInfos.TryGetValue(instanceName, out var info))
+                            {
+                                name = info.Name;
+                            }
+
+                            var monitor = new Monitor
+                            {
+                                Id = $"WMI_{instanceName}",
+                                Name = name,
+                                Type = MonitorType.Internal,
+                                CurrentBrightness = currentBrightness,
+                                MinBrightness = 0,
+                                MaxBrightness = 100,
+                                IsAvailable = true,
+                                InstanceName = instanceName,
+                                Capabilities = MonitorCapabilities.Brightness | MonitorCapabilities.Wmi,
+                                ConnectionType = "Internal",
+                                CommunicationMethod = "WMI",
+                                Manufacturer = "Internal",
+                                SupportsColorTemperature = false,
+                            };
+
+                            monitors.Add(monitor);
+                        }
+                        catch (Exception ex)
+                        {
+                            // Skip problematic monitors
+                            Logger.LogWarning($"Failed to create monitor from WMI data: {ex.Message}");
+                        }
+                    }
+                }
+                catch (WmiException ex)
+                {
+                    // Return empty list instead of throwing exception
+                    Logger.LogError($"WMI DiscoverMonitors failed: {ex.Message} (HResult: 0x{ex.HResult:X})");
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"WMI DiscoverMonitors failed: {ex.Message}");
+                }
+
+                return monitors;
+            },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Validate monitor connection status
+        /// </summary>
+        public async Task<bool> ValidateConnectionAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return await Task.Run(
+                () =>
+                {
+                    try
+                    {
+                        // Try to read current brightness to validate connection
+                        using var connection = new WmiConnection(WmiNamespace);
+                        var query = $"SELECT CurrentBrightness FROM {BrightnessQueryClass} WHERE InstanceName='{monitor.InstanceName}'";
+                        var results = connection.CreateQuery(query).ToList();
+                        return results.Count > 0;
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogWarning($"WMI ValidateConnection failed for {monitor.InstanceName}: {ex.Message}");
+                        return false;
+                    }
+                },
+                cancellationToken);
+        }
+
+        /// <summary>
+        /// Get user-friendly name from WMI object
+        /// </summary>
+        private static string? GetUserFriendlyName(WmiObject monitorObject)
+        {
+            try
+            {
+                // WmiLight returns arrays as object arrays
+                var userFriendlyNameObj = monitorObject.GetPropertyValue<object>("UserFriendlyName");
+
+                if (userFriendlyNameObj is ushort[] userFriendlyName && userFriendlyName.Length > 0)
+                {
+                    // Convert UINT16 array to string
+                    var chars = userFriendlyName
+                        .Where(c => c != 0)
+                        .Select(c => (char)c)
+                        .ToArray();
+
+                    if (chars.Length > 0)
+                    {
+                        return new string(chars).Trim();
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                // Ignore conversion errors
+                Logger.LogDebug($"Failed to parse UserFriendlyName: {ex.Message}");
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Check WMI service availability
+        /// </summary>
+        public static bool IsWmiAvailable()
+        {
+            try
+            {
+                using var connection = new WmiConnection(WmiNamespace);
+                var query = $"SELECT * FROM {BrightnessQueryClass}";
+                var results = connection.CreateQuery(query).ToList();
+                return results.Count > 0;
+            }
+            catch (WmiException ex) when (ex.HResult == 0x1068)
+            {
+                // Expected on systems without WMI brightness support (desktops, some laptops)
+                Logger.LogInfo("WMI brightness control not supported on this system (expected for desktops)");
+                return false;
+            }
+            catch (Exception ex)
+            {
+                // Unexpected error during WMI check
+                Logger.LogDebug($"WMI availability check failed: {ex.Message}");
+                return false;
+            }
+        }
+
+        /// <summary>
+        /// Check if administrator privileges are required
+        /// </summary>
+        public static bool RequiresElevation()
+        {
+            try
+            {
+                using var connection = new WmiConnection(WmiNamespace);
+                var query = $"SELECT * FROM {BrightnessMethodClass}";
+                var results = connection.CreateQuery(query).ToList();
+
+                foreach (var obj in results)
+                {
+                    // Try to call method to check permissions
+                    try
+                    {
+                        using (WmiMethod method = obj.GetMethod("WmiSetBrightness"))
+                        using (WmiMethodParameters inParams = method.CreateInParameters())
+                        {
+                            inParams.SetPropertyValue("Timeout", 0u);
+                            inParams.SetPropertyValue("Brightness", (byte)50);
+                            obj.ExecuteMethod<uint>(method, inParams, out WmiMethodParameters outParams);
+                            return false; // If successful, no elevation required
+                        }
+                    }
+                    catch (UnauthorizedAccessException)
+                    {
+                        return true; // Administrator privileges required
+                    }
+                    catch (Exception ex)
+                    {
+                        // Other errors may not be permission issues
+                        Logger.LogDebug($"WMI RequiresElevation check error: {ex.Message}");
+                        return false;
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                // Cannot determine, assume privileges required
+                Logger.LogWarning($"WMI RequiresElevation check failed: {ex.Message}");
+                return true;
+            }
+
+            return false;
+        }
+
+        // Extended features not supported by WMI
+        public Task<BrightnessInfo> GetContrastAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(BrightnessInfo.Invalid);
+        }
+
+        public Task<MonitorOperationResult> SetContrastAsync(Monitor monitor, int contrast, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(MonitorOperationResult.Failure("Contrast control not supported via WMI"));
+        }
+
+        public Task<BrightnessInfo> GetVolumeAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(BrightnessInfo.Invalid);
+        }
+
+        public Task<MonitorOperationResult> SetVolumeAsync(Monitor monitor, int volume, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(MonitorOperationResult.Failure("Volume control not supported via WMI"));
+        }
+
+        public Task<BrightnessInfo> GetColorTemperatureAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(BrightnessInfo.Invalid);
+        }
+
+        public Task<MonitorOperationResult> SetColorTemperatureAsync(Monitor monitor, int colorTemperature, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(MonitorOperationResult.Failure("Color temperature control not supported via WMI"));
+        }
+
+        public Task<string> GetCapabilitiesStringAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(string.Empty);
+        }
+
+        public Task<MonitorOperationResult> SaveCurrentSettingsAsync(Monitor monitor, CancellationToken cancellationToken = default)
+        {
+            return Task.FromResult(MonitorOperationResult.Failure("Save settings not supported via WMI"));
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!_disposed && disposing)
+            {
+                // WmiLight objects are automatically cleaned up, no specific cleanup needed here
+                _disposed = true;
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Native/WindowHelper.cs

@@ -0,0 +1,170 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using static PowerDisplay.Native.PInvoke;
+
+namespace PowerDisplay.Native
+{
+    internal static class WindowHelper
+    {
+        // Window Styles
+        private const int GwlStyle = -16;
+        private const int WsCaption = 0x00C00000;
+        private const int WsThickframe = 0x00040000;
+        private const int WsMinimizebox = 0x00020000;
+        private const int WsMaximizebox = 0x00010000;
+        private const int WsSysmenu = 0x00080000;
+
+        // Extended Window Styles
+        private const int GwlExstyle = -20;
+        private const int WsExDlgmodalframe = 0x00000001;
+        private const int WsExWindowedge = 0x00000100;
+        private const int WsExClientedge = 0x00000200;
+        private const int WsExStaticedge = 0x00020000;
+        private const int WsExToolwindow = 0x00000080;
+
+        // Window Messages
+        private const int WmNclbuttondown = 0x00A1;
+        private const int WmSyscommand = 0x0112;
+        private const int ScMove = 0xF010;
+
+        private const uint SwpNosize = 0x0001;
+        private const uint SwpNomove = 0x0002;
+        private const uint SwpFramechanged = 0x0020;
+        private static readonly IntPtr HwndTopmost = new IntPtr(-1);
+        private static readonly IntPtr HwndNotopmost = new IntPtr(-2);
+
+        // ShowWindow commands
+        private const int SwHide = 0;
+        private const int SwShow = 5;
+        private const int SwMinimize = 6;
+        private const int SwRestore = 9;
+
+        /// <summary>
+        /// 禁用窗口的拖动和缩放功能
+        /// </summary>
+        public static void DisableWindowMovingAndResizing(IntPtr hWnd)
+        {
+            // 获取当前窗口样式
+#if WIN64
+            int style = (int)GetWindowLong(hWnd, GwlStyle);
+#else
+            int style = GetWindowLong(hWnd, GwlStyle);
+#endif
+
+            // 移除可调整大小的边框、标题栏和系统菜单
+            style &= ~WsThickframe;
+            style &= ~WsMaximizebox;
+            style &= ~WsMinimizebox;
+            style &= ~WsCaption;  // 移除整个标题栏
+            style &= ~WsSysmenu;   // 移除系统菜单
+
+            // 设置新的窗口样式
+#if WIN64
+            _ = SetWindowLong(hWnd, GwlStyle, new IntPtr(style));
+#else
+            _ = SetWindowLong(hWnd, GwlStyle, style);
+#endif
+
+            // 获取扩展样式并移除相关边框
+#if WIN64
+            int exStyle = (int)GetWindowLong(hWnd, GwlExstyle);
+#else
+            int exStyle = GetWindowLong(hWnd, GwlExstyle);
+#endif
+            exStyle &= ~WsExDlgmodalframe;
+            exStyle &= ~WsExWindowedge;
+            exStyle &= ~WsExClientedge;
+            exStyle &= ~WsExStaticedge;
+#if WIN64
+            _ = SetWindowLong(hWnd, GwlExstyle, new IntPtr(exStyle));
+#else
+            _ = SetWindowLong(hWnd, GwlExstyle, exStyle);
+#endif
+
+            // 刷新窗口框架
+            SetWindowPos(
+                hWnd,
+                IntPtr.Zero,
+                0,
+                0,
+                0,
+                0,
+                SwpNomove | SwpNosize | SwpFramechanged);
+        }
+
+        /// <summary>
+        /// 设置窗口是否置顶
+        /// </summary>
+        public static void SetWindowTopmost(IntPtr hWnd, bool topmost)
+        {
+            SetWindowPos(
+                hWnd,
+                topmost ? HwndTopmost : HwndNotopmost,
+                0,
+                0,
+                0,
+                0,
+                SwpNomove | SwpNosize);
+        }
+
+        /// <summary>
+        /// 显示或隐藏窗口
+        /// </summary>
+        public static void ShowWindow(IntPtr hWnd, bool show)
+        {
+            PInvoke.ShowWindow(hWnd, show ? SwShow : SwHide);
+        }
+
+        /// <summary>
+        /// 最小化窗口
+        /// </summary>
+        public static void MinimizeWindow(IntPtr hWnd)
+        {
+            PInvoke.ShowWindow(hWnd, SwMinimize);
+        }
+
+        /// <summary>
+        /// 恢复窗口
+        /// </summary>
+        public static void RestoreWindow(IntPtr hWnd)
+        {
+            PInvoke.ShowWindow(hWnd, SwRestore);
+        }
+
+        /// <summary>
+        /// 设置窗口不在任务栏显示
+        /// </summary>
+        public static void HideFromTaskbar(IntPtr hWnd)
+        {
+            // 获取当前扩展样式
+#if WIN64
+            int exStyle = (int)GetWindowLong(hWnd, GwlExstyle);
+#else
+            int exStyle = GetWindowLong(hWnd, GwlExstyle);
+#endif
+
+            // 添加 WS_EX_TOOLWINDOW 样式，这会让窗口不在任务栏显示
+            exStyle |= WsExToolwindow;
+
+            // 设置新的扩展样式
+#if WIN64
+            _ = SetWindowLong(hWnd, GwlExstyle, new IntPtr(exStyle));
+#else
+            _ = SetWindowLong(hWnd, GwlExstyle, exStyle);
+#endif
+
+            // 刷新窗口框架
+            SetWindowPos(
+                hWnd,
+                IntPtr.Zero,
+                0,
+                0,
+                0,
+                0,
+                SwpNomove | SwpNosize | SwpFramechanged);
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/PowerDisplay.csproj

@@ -0,0 +1,86 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <!-- Look at Directory.Build.props in root for common stuff as well -->
+  <Import Project="..\..\..\Common.Dotnet.CsWinRT.props" />
+  <Import Project="..\..\..\Common.SelfContained.props" />
+  <Import Project="..\..\..\Common.Dotnet.AotCompatibility.props" />
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <RootNamespace>PowerDisplay</RootNamespace>
+    <ApplicationManifest>app.manifest</ApplicationManifest>
+    <Platforms>x64;ARM64</Platforms>
+    <UseWinUI>true</UseWinUI>
+    <EnableMsixTooling>true</EnableMsixTooling>
+    <EnablePreviewMsixTooling>true</EnablePreviewMsixTooling>
+    <WindowsPackageType>None</WindowsPackageType>
+    <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
+    <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
+    <WindowsAppSDKSelfContained>true</WindowsAppSDKSelfContained>
+    <OutputPath>..\..\..\..\$(Platform)\$(Configuration)\WinUI3Apps</OutputPath>
+    <AssemblyName>PowerToys.PowerDisplay</AssemblyName>
+    <ApplicationIcon>Assets\PowerDisplay.ico</ApplicationIcon>
+    <!-- MRT from windows app sdk will search for a pri file with the same name of the module before defaulting to resources.pri -->
+    <ProjectPriFileName>PowerToys.PowerDisplay.pri</ProjectPriFileName>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <Nullable>enable</Nullable>
+    <!-- Disable XAML-generated Main method, use custom Program.cs -->
+    <DefineConstants>DISABLE_XAML_GENERATED_MAIN</DefineConstants>
+  </PropertyGroup>
+  <!-- Native AOT Configuration -->
+  <PropertyGroup>
+    <PublishSingleFile>false</PublishSingleFile>
+    <DisableRuntimeMarshalling>false</DisableRuntimeMarshalling>
+    <PublishAot>true</PublishAot>
+    <TrimmerSingleWarn>false</TrimmerSingleWarn>
+    <SuppressTrimAnalysisWarnings>false</SuppressTrimAnalysisWarnings>
+  </PropertyGroup>
+  <ItemGroup>
+    <Page Remove="PowerDisplayXAML\App.xaml" />
+  </ItemGroup>
+  <ItemGroup>
+    <ApplicationDefinition Include="PowerDisplayXAML\App.xaml" />
+  </ItemGroup>
+  <ItemGroup>
+    <Folder Include="PowerDisplayXAML\" />
+  </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.WindowsAppSDK" />
+    <PackageReference Include="Microsoft.Windows.SDK.BuildTools" />
+    <PackageReference Include="WmiLight" />
+    <PackageReference Include="System.Collections.Immutable" />
+    <PackageReference Include="CommunityToolkit.WinUI.Controls.SettingsControls" />
+    <PackageReference Include="CommunityToolkit.WinUI.Animations" />
+    <PackageReference Include="CommunityToolkit.WinUI.Extensions" />
+    <PackageReference Include="CommunityToolkit.WinUI.Controls.Segmented" />
+    <PackageReference Include="CommunityToolkit.WinUI.Controls.Sizers" />
+    <PackageReference Include="CommunityToolkit.WinUI.Converters" />
+    <Manifest Include="$(ApplicationManifest)" />
+  </ItemGroup>
+  <!--
+    Defining the "Msix" ProjectCapability here allows the Single-project MSIX Packaging
+    Tools extension to be activated for this project even if the Windows App SDK Nuget
+    package has not yet been restored.
+  -->
+  <ItemGroup Condition="'$(DisableMsixProjectCapabilityAddedByProject)'!='true' and '$(EnableMsixTooling)'=='true'">
+    <ProjectCapability Include="Msix" />
+  </ItemGroup>
+  <ItemGroup>
+    <!-- Removed Common.UI dependency - SettingsDeepLink is now implemented locally -->
+    <ProjectReference Include="..\..\..\common\ManagedCommon\ManagedCommon.csproj" />
+    <ProjectReference Include="..\..\..\common\ManagedCsWin32\ManagedCsWin32.csproj" />
+    <ProjectReference Include="..\..\..\settings-ui\Settings.UI.Library\Settings.UI.Library.csproj" />
+  </ItemGroup>
+  <!-- Copy Assets folder to output directory -->
+  <ItemGroup>
+    <Content Include="Assets\**\*">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+  <!--
+    Defining the "HasPackageAndPublishMenuAddedByProject" property here allows the Solution
+    Explorer "Package and Publish" context menu entry to be enabled for this project even if
+    the Windows App SDK Nuget package has not yet been restored.
+  -->
+  <PropertyGroup Condition="'$(DisableHasPackageAndPublishMenuAddedByProject)'!='true' and '$(EnableMsixTooling)'=='true'">
+    <HasPackageAndPublishMenu>true</HasPackageAndPublishMenu>
+  </PropertyGroup>
+</Project>

src/modules/powerdisplay/PowerDisplay/PowerDisplayXAML/App.xaml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Application x:Class="PowerDisplay.App"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:converters="using:PowerDisplay.Converters"
+             xmlns:toolkit="using:CommunityToolkit.WinUI">
+    <Application.Resources>
+        <ResourceDictionary>
+            <ResourceDictionary.MergedDictionaries>
+                <!-- WinUI 3 System Resources -->
+                <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
+            </ResourceDictionary.MergedDictionaries>
+
+            <!-- Converters -->
+            <converters:BoolToVisibilityConverter x:Key="BoolToVisibilityConverter"/>
+            <converters:InverseBoolToVisibilityConverter x:Key="InverseBoolToVisibilityConverter"/>
+            <converters:InverseBoolConverter x:Key="InverseBoolConverter"/>
+
+        </ResourceDictionary>
+    </Application.Resources>
+</Application>

src/modules/powerdisplay/PowerDisplay/PowerDisplayXAML/App.xaml.cs

@@ -0,0 +1,540 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using ManagedCommon;
+using Microsoft.PowerToys.Telemetry;
+using Microsoft.UI.Dispatching;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Media;
+using Microsoft.Windows.AppLifecycle;
+using PowerDisplay.Helpers;
+using PowerDisplay.Serialization;
+
+namespace PowerDisplay
+{
+    /// <summary>
+    /// PowerDisplay application main class
+    /// </summary>
+    public partial class App : Application
+    {
+        private Window? _mainWindow;
+        private int _powerToysRunnerPid;
+        private string _pipeUuid = string.Empty;
+        private static Mutex? _mutex;
+
+        // Bidirectional named pipes for IPC
+        private static System.IO.Pipes.NamedPipeClientStream? _readPipe;  // Read from ModuleInterface (OUT pipe)
+        private static System.IO.Pipes.NamedPipeClientStream? _writePipe; // Write to ModuleInterface (IN pipe)
+        private static Thread? _messageReceiverThread;
+        private static bool _stopReceiver;
+
+        /// <summary>
+        /// Sends IPC message to Settings UI via ModuleInterface
+        /// </summary>
+        public static void SendIPCMessage(string message)
+        {
+            try
+            {
+                if (_writePipe != null && _writePipe.IsConnected)
+                {
+                    var writer = new System.IO.StreamWriter(_writePipe) { AutoFlush = true };
+                    writer.WriteLine(message);
+                    Logger.LogTrace($"Sent IPC message: {message}");
+                }
+                else
+                {
+                    Logger.LogWarning("Cannot send IPC message: pipe not connected");
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to send IPC message: {ex.Message}");
+            }
+        }
+
+        public App(int runnerPid, string pipeUuid)
+        {
+            _powerToysRunnerPid = runnerPid;
+            _pipeUuid = pipeUuid;
+
+            this.InitializeComponent();
+
+            // Ensure types used in XAML are preserved for AOT compilation
+            TypePreservation.PreserveTypes();
+
+            // Initialize Logger
+            Logger.InitializeLogger("\\PowerDisplay\\Logs");
+
+            // Initialize PowerToys telemetry
+            try
+            {
+                PowerToysTelemetry.Log.WriteEvent(new Telemetry.Events.PowerDisplayStartEvent());
+            }
+            catch
+            {
+                // Telemetry errors should not crash the app
+            }
+
+            // Initialize language settings
+            string appLanguage = LanguageHelper.LoadLanguage();
+            if (!string.IsNullOrEmpty(appLanguage))
+            {
+                Microsoft.Windows.Globalization.ApplicationLanguages.PrimaryLanguageOverride = appLanguage;
+            }
+
+            // Handle unhandled exceptions
+            this.UnhandledException += OnUnhandledException;
+        }
+
+        /// <summary>
+        /// Handle unhandled exceptions
+        /// </summary>
+        private void OnUnhandledException(object sender, Microsoft.UI.Xaml.UnhandledExceptionEventArgs e)
+        {
+            // Try to display error information
+            ShowStartupError(e.Exception);
+
+            // Mark exception as handled to prevent app crash
+            e.Handled = true;
+        }
+
+        /// <summary>
+        /// Called when the application is launched
+        /// </summary>
+        /// <param name="args">Launch arguments</param>
+        protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
+        {
+            try
+            {
+                // Use Mutex to ensure only one PowerDisplay instance is running
+                _mutex = new Mutex(true, "PowerDisplay", out bool isNewInstance);
+
+                if (!isNewInstance)
+                {
+                    // PowerDisplay is already running, exit current instance
+                    Logger.LogInfo("PowerDisplay is already running. Exiting duplicate instance.");
+                    Environment.Exit(0);
+                    return;
+                }
+
+                // Ensure Mutex is released when app exits
+                AppDomain.CurrentDomain.ProcessExit += (_, _) => _mutex?.ReleaseMutex();
+
+                // Parse command line arguments
+                var cmdArgs = Environment.GetCommandLineArgs();
+                if (cmdArgs?.Length > 1)
+                {
+                    // Support two formats: direct PID or --pid PID
+                    int pidValue = -1;
+
+                    // Check if using --pid format
+                    for (int i = 1; i < cmdArgs.Length - 1; i++)
+                    {
+                        if (cmdArgs[i] == "--pid" && int.TryParse(cmdArgs[i + 1], out pidValue))
+                        {
+                            break;
+                        }
+                    }
+
+                    // If not --pid format, try parsing last argument (compatible with old format)
+                    if (pidValue == -1 && cmdArgs.Length > 1)
+                    {
+                        _ = int.TryParse(cmdArgs[cmdArgs.Length - 1], out pidValue);
+                    }
+
+                    if (pidValue > 0)
+                    {
+                        _powerToysRunnerPid = pidValue;
+
+                        // Started from PowerToys Runner
+                        Logger.LogInfo($"PowerDisplay started from PowerToys Runner. Runner pid={_powerToysRunnerPid}");
+
+                        // Monitor parent process
+                        RunnerHelper.WaitForPowerToysRunner(_powerToysRunnerPid, () =>
+                        {
+                            Logger.LogInfo("PowerToys Runner exited. Exiting PowerDisplay");
+                            ForceExit();
+                        });
+                    }
+                }
+                else
+                {
+                    // Standalone mode
+                    Logger.LogInfo("PowerDisplay started detached from PowerToys Runner.");
+                    _powerToysRunnerPid = -1;
+                }
+
+                // Initialize IPC in background (non-blocking)
+                // Only connect pipes when launched from PowerToys (not standalone)
+                if (!string.IsNullOrEmpty(_pipeUuid) && _powerToysRunnerPid != -1)
+                {
+                    // Async pipe connection in background - don't block UI thread
+                    _ = Task.Run(() => InitializeBidirectionalPipes(_pipeUuid));
+                    Logger.LogInfo("Starting IPC pipe connection in background");
+                }
+                else
+                {
+                    Logger.LogInfo("Running in standalone mode, IPC disabled");
+                }
+
+                // Create main window but don't activate, window will auto-hide after initialization
+                _mainWindow = new MainWindow();
+            }
+            catch (Exception ex)
+            {
+                ShowStartupError(ex);
+            }
+        }
+
+        /// <summary>
+        /// Initialize bidirectional named pipes for IPC with ModuleInterface
+        /// </summary>
+        private void InitializeBidirectionalPipes(string pipeUuid)
+        {
+            try
+            {
+                // Pipe names based on UUID from ModuleInterface
+                string pipeNameIn = $"powertoys_powerdisplay_{pipeUuid}_in";   // Write to this (ModuleInterface reads)
+                string pipeNameOut = $"powertoys_powerdisplay_{pipeUuid}_out"; // Read from this (ModuleInterface writes)
+
+                Logger.LogInfo($"Connecting to pipes: IN={pipeNameIn}, OUT={pipeNameOut}");
+
+                // Connect to write pipe (IN pipe from ModuleInterface perspective)
+                _writePipe = new System.IO.Pipes.NamedPipeClientStream(
+                    ".",
+                    pipeNameIn,
+                    System.IO.Pipes.PipeDirection.Out);
+                _writePipe.Connect(2000); // 2 second timeout (reduced from 5s, we're in background thread)
+
+                // Connect to read pipe (OUT pipe from ModuleInterface perspective)
+                _readPipe = new System.IO.Pipes.NamedPipeClientStream(
+                    ".",
+                    pipeNameOut,
+                    System.IO.Pipes.PipeDirection.In);
+                _readPipe.Connect(2000); // 2 second timeout (reduced from 5s)
+
+                Logger.LogInfo("Successfully connected to bidirectional pipes");
+
+                // Start message receiver thread
+                _stopReceiver = false;
+                _messageReceiverThread = new Thread(MessageReceiverThreadProc)
+                {
+                    IsBackground = true,
+                    Name = "PowerDisplay IPC Receiver",
+                };
+                _messageReceiverThread.Start();
+            }
+            catch (Exception ex)
+            {
+                Logger.LogWarning($"Failed to initialize bidirectional pipes: {ex.Message}. App will continue in standalone mode.");
+
+                // Clean up on failure
+                try
+                {
+                    _writePipe?.Dispose();
+                    _readPipe?.Dispose();
+                    _writePipe = null;
+                    _readPipe = null;
+                }
+                catch
+                {
+                    // Ignore cleanup errors
+                }
+            }
+        }
+
+        /// <summary>
+        /// Message receiver thread procedure
+        /// </summary>
+        private static void MessageReceiverThreadProc()
+        {
+            Logger.LogInfo("Message receiver thread started");
+
+            try
+            {
+                if (_readPipe == null || !_readPipe.IsConnected)
+                {
+                    Logger.LogError("Read pipe is not connected");
+                    return;
+                }
+
+                var reader = new System.IO.StreamReader(_readPipe);
+
+                while (!_stopReceiver && _readPipe.IsConnected)
+                {
+                    try
+                    {
+                        string? message = reader.ReadLine();
+                        if (message != null)
+                        {
+                            OnIPCMessageReceived(message);
+                        }
+                    }
+                    catch (System.IO.IOException)
+                    {
+                        // Pipe disconnected
+                        Logger.LogWarning("Pipe disconnected");
+                        break;
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError($"Error reading from pipe: {ex.Message}");
+                        break;
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Message receiver thread error: {ex.Message}");
+            }
+
+            Logger.LogInfo("Message receiver thread exiting");
+        }
+
+        /// <summary>
+        /// Handle IPC messages received from ModuleInterface/Settings UI
+        /// </summary>
+        private static void OnIPCMessageReceived(string message)
+        {
+            try
+            {
+                Logger.LogInfo($"Received IPC message: {message}");
+
+                // Parse JSON message and handle commands (using source-generated context for AOT)
+                // Expected format: {"action": "command_name", ...}
+                var ipcMessage = System.Text.Json.JsonSerializer.Deserialize(message, AppJsonContext.Default.IPCMessageAction);
+                if (ipcMessage?.Action != null)
+                {
+                    string action = ipcMessage.Action;
+
+                    switch (action)
+                    {
+                        case "show_window":
+                            Logger.LogInfo("Received show_window command");
+
+                            // TODO: Implement window show logic
+                            break;
+
+                        case "toggle_window":
+                            Logger.LogInfo("Received toggle_window command");
+
+                            // TODO: Implement window toggle logic
+                            break;
+
+                        case "refresh_monitors":
+                            Logger.LogInfo("Received refresh_monitors command");
+
+                            // TODO: Implement monitor refresh logic
+                            break;
+
+                        case "settings_updated":
+                            Logger.LogInfo("Received settings_updated command");
+
+                            // TODO: Implement settings update logic
+                            break;
+
+                        case "terminate":
+                            Logger.LogInfo("Received terminate command");
+
+                            // TODO: Implement graceful shutdown
+                            break;
+
+                        default:
+                            Logger.LogWarning($"Unknown action received: {action}");
+                            break;
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Error processing IPC message: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Show startup error
+        /// </summary>
+        private void ShowStartupError(Exception ex)
+        {
+            try
+            {
+                Logger.LogError($"PowerDisplay startup failed: {ex.Message}");
+
+                var errorWindow = new Window { Title = "PowerDisplay - Startup Error" };
+                var panel = new StackPanel { Margin = new Thickness(20), Spacing = 16 };
+
+                panel.Children.Add(new TextBlock
+                {
+                    Text = "PowerDisplay Startup Failed",
+                    FontSize = 20,
+                    FontWeight = Microsoft.UI.Text.FontWeights.SemiBold,
+                });
+
+                panel.Children.Add(new TextBlock
+                {
+                    Text = $"Error: {ex.Message}",
+                    FontSize = 14,
+                    TextWrapping = TextWrapping.Wrap,
+                });
+
+                panel.Children.Add(new TextBlock
+                {
+                    Text = $"Details:\n{ex}",
+                    FontSize = 12,
+                    TextWrapping = TextWrapping.Wrap,
+                    Foreground = new SolidColorBrush(Microsoft.UI.Colors.Gray),
+                    Margin = new Thickness(0, 10, 0, 0),
+                });
+
+                var closeButton = new Button
+                {
+                    Content = "Close",
+                    HorizontalAlignment = HorizontalAlignment.Right,
+                    Margin = new Thickness(0, 10, 0, 0),
+                };
+                closeButton.Click += (_, _) => errorWindow.Close();
+                panel.Children.Add(closeButton);
+
+                errorWindow.Content = new ScrollViewer
+                {
+                    Content = panel,
+                    VerticalScrollBarVisibility = ScrollBarVisibility.Auto,
+                    MaxHeight = 600,
+                    MaxWidth = 800,
+                };
+
+                errorWindow.Activate();
+            }
+            catch
+            {
+                Environment.Exit(1);
+            }
+        }
+
+        /// <summary>
+        /// Gets the main window instance
+        /// </summary>
+        public Window? MainWindow => _mainWindow;
+
+        /// <summary>
+        /// Check if running standalone (not launched from PowerToys Runner)
+        /// </summary>
+        public bool IsRunningDetachedFromPowerToys()
+        {
+            return _powerToysRunnerPid == -1;
+        }
+
+        /// <summary>
+        /// Quick cleanup when application exits
+        /// </summary>
+        public void Shutdown()
+        {
+            try
+            {
+                // Start timeout mechanism, ensure exit within 1 second
+                var timeoutTimer = new System.Threading.Timer(
+                    _ =>
+                    {
+                        Logger.LogWarning("Shutdown timeout reached, forcing exit");
+                        Environment.Exit(0);
+                    },
+                    null,
+                    1000,
+                    System.Threading.Timeout.Infinite);
+
+                // Immediately notify MainWindow that program is exiting, enable fast shutdown mode
+                if (_mainWindow is MainWindow mainWindow)
+                {
+                    mainWindow.SetExiting();
+                    mainWindow.FastShutdown();
+                }
+
+                _mainWindow = null;
+
+                // Clean up IPC pipes
+                try
+                {
+                    _stopReceiver = true;
+                    _messageReceiverThread?.Join(1000); // Wait max 1 second
+
+                    _readPipe?.Close();
+                    _readPipe?.Dispose();
+                    _readPipe = null;
+
+                    _writePipe?.Close();
+                    _writePipe?.Dispose();
+                    _writePipe = null;
+                }
+                catch
+                {
+                    // Ignore IPC cleanup errors
+                }
+
+                // Immediately release Mutex
+                _mutex?.ReleaseMutex();
+                _mutex?.Dispose();
+                _mutex = null;
+
+                // Cancel timeout timer
+                timeoutTimer?.Dispose();
+            }
+            catch
+            {
+                // Ignore cleanup errors, ensure exit
+                Environment.Exit(0);
+            }
+        }
+
+        /// <summary>
+        /// Force exit application, ensure complete termination
+        /// </summary>
+        private void ForceExit()
+        {
+            try
+            {
+                // Immediately start timeout mechanism, must exit within 500ms
+                var emergencyTimer = new System.Threading.Timer(
+                    _ =>
+                    {
+                        Logger.LogWarning("Emergency exit timeout reached, terminating process");
+                        Environment.Exit(0);
+                    },
+                    null,
+                    500,
+                    System.Threading.Timeout.Infinite);
+
+                PerformForceExit();
+            }
+            catch
+            {
+                // If all other methods fail, immediately force exit process
+                Environment.Exit(0);
+            }
+        }
+
+        /// <summary>
+        /// Perform fast exit operation
+        /// </summary>
+        private void PerformForceExit()
+        {
+            try
+            {
+                // Fast shutdown
+                Shutdown();
+
+                // Immediately exit
+                Environment.Exit(0);
+            }
+            catch
+            {
+                // Ensure exit
+                Environment.Exit(0);
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/PowerDisplayXAML/MainWindow.xaml

@@ -0,0 +1,394 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Window x:Class="PowerDisplay.MainWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:PowerDisplay.ViewModels"
+        xmlns:converters="using:PowerDisplay.Converters"
+        xmlns:toolkit="using:CommunityToolkit.WinUI.Controls"
+        xmlns:ui="using:CommunityToolkit.WinUI"
+        xmlns:animations="using:CommunityToolkit.WinUI.Animations">
+    <Grid x:Name="RootGrid">
+        <Grid.RenderTransform>
+            <TranslateTransform x:Name="RootGridTransform" X="0" />
+        </Grid.RenderTransform>
+
+        <Grid.Resources>
+            <!-- Enhanced Slide-in animation storyboard -->
+            <Storyboard x:Key="SlideInStoryboard">
+                <DoubleAnimation Storyboard.TargetName="RootGridTransform"
+                               Storyboard.TargetProperty="X"
+                               From="300"
+                               To="0"
+                               Duration="0:0:0.4">
+                    <DoubleAnimation.EasingFunction>
+                        <CubicEase EasingMode="EaseOut" />
+                    </DoubleAnimation.EasingFunction>
+                </DoubleAnimation>
+                <DoubleAnimation Storyboard.TargetName="RootGrid"
+                               Storyboard.TargetProperty="Opacity"
+                               From="0"
+                               To="1"
+                               Duration="0:0:0.3" />
+                <DoubleAnimation Storyboard.TargetName="MainContainer"
+                               Storyboard.TargetProperty="(UIElement.RenderTransform).(TranslateTransform.Y)"
+                               From="20"
+                               To="0"
+                               Duration="0:0:0.5">
+                    <DoubleAnimation.EasingFunction>
+                        <CubicEase EasingMode="EaseOut" />
+                    </DoubleAnimation.EasingFunction>
+                </DoubleAnimation>
+            </Storyboard>
+
+            <!-- Enhanced Slide-out animation storyboard -->
+            <Storyboard x:Key="SlideOutStoryboard">
+                <DoubleAnimation Storyboard.TargetName="RootGridTransform"
+                               Storyboard.TargetProperty="X"
+                               From="0"
+                               To="300"
+                               Duration="0:0:0.3">
+                    <DoubleAnimation.EasingFunction>
+                        <CubicEase EasingMode="EaseIn" />
+                    </DoubleAnimation.EasingFunction>
+                </DoubleAnimation>
+                <DoubleAnimation Storyboard.TargetName="RootGrid"
+                               Storyboard.TargetProperty="Opacity"
+                               From="1"
+                               To="0"
+                               Duration="0:0:0.2" />
+            </Storyboard>
+        </Grid.Resources>
+
+        <!-- Main Container with modern design -->
+        <Border x:Name="MainContainer"
+                CornerRadius="8"
+                Background="{ThemeResource LayerFillColorDefaultBrush}"
+                BorderBrush="{ThemeResource CardStrokeColorDefaultBrush}"
+                BorderThickness="1"
+                Margin="0"
+                MaxWidth="640"
+                HorizontalAlignment="Stretch"
+                VerticalAlignment="Top">
+            <Border.RenderTransform>
+                <TranslateTransform Y="0" />
+            </Border.RenderTransform>
+
+            <Grid>
+                <Grid.RowDefinitions>
+                    <RowDefinition Height="Auto" />
+                    <RowDefinition Height="Auto" />
+                </Grid.RowDefinitions>
+
+                <!-- Content Area -->
+                <ScrollViewer Grid.Row="0"
+                             ZoomMode="Disabled"
+                             HorizontalScrollMode="Disabled"
+                             HorizontalScrollBarVisibility="Disabled"
+                             VerticalScrollBarVisibility="Auto"
+                             MaxHeight="420"
+                             Padding="8">
+
+                    <StackPanel Spacing="4">
+
+                        <!-- Loading State with modern progress -->
+                        <StackPanel Orientation="Vertical"
+                                   Spacing="16"
+                                   HorizontalAlignment="Center"
+                                   VerticalAlignment="Center"
+                                   Visibility="{x:Bind ConvertBoolToVisibility(ViewModel.IsScanning), Mode=OneWay}">
+                            <ProgressRing IsActive="True"
+                                         Width="32"
+                                         Height="32"
+                                         Foreground="{ThemeResource AccentFillColorDefaultBrush}" />
+                            <TextBlock x:Name="ScanningMonitorsTextBlock"
+                                      FontSize="12"
+                                      HorizontalAlignment="Center"
+                                      TextAlignment="Center" />
+                        </StackPanel>
+
+                        <!-- No Monitors State with InfoBar -->
+                        <InfoBar x:Name="NoMonitorsInfoBar"
+                                        IsOpen="{x:Bind ViewModel.ShowNoMonitorsMessage, Mode=OneWay}"
+                                        Severity="Informational"
+                                        IsClosable="False"
+                                        Background="{ThemeResource InfoBarInformationalSeverityBackgroundBrush}">
+                            <InfoBar.IconSource>
+                                <FontIconSource Glyph="&#xE7F4;" />
+                            </InfoBar.IconSource>
+                            <TextBlock x:Name="NoMonitorsTextBlock" />
+                        </InfoBar>
+
+                        <!-- Monitors List with modern card design -->
+                        <ItemsControl ItemsSource="{x:Bind ViewModel.Monitors, Mode=OneWay}"
+                                     Visibility="{x:Bind ConvertBoolToVisibility(ViewModel.HasMonitors), Mode=OneWay}"
+                                     HorizontalAlignment="Stretch">
+                            <ItemsControl.ItemsPanel>
+                                <ItemsPanelTemplate>
+                                    <StackPanel Orientation="Vertical"
+                                               Spacing="0">
+                                        <StackPanel.ChildrenTransitions>
+                                            <TransitionCollection>
+                                                <EntranceThemeTransition FromVerticalOffset="20" />
+                                                <RepositionThemeTransition IsStaggeringEnabled="True" />
+                                            </TransitionCollection>
+                                        </StackPanel.ChildrenTransitions>
+                                    </StackPanel>
+                                </ItemsPanelTemplate>
+                            </ItemsControl.ItemsPanel>
+
+                            <ItemsControl.ItemTemplate>
+                                <DataTemplate x:DataType="vm:MonitorViewModel">
+                                    <StackPanel Spacing="2" HorizontalAlignment="Stretch">
+                                        <StackPanel.ChildrenTransitions>
+                                            <TransitionCollection>
+                                                <EntranceThemeTransition FromVerticalOffset="8" />
+                                                <RepositionThemeTransition />
+                                            </TransitionCollection>
+                                        </StackPanel.ChildrenTransitions>
+
+                                        <!-- Monitor Name with Icon -->
+                                        <StackPanel Orientation="Horizontal"
+                                                    Spacing="12"
+                                                    Padding="12,8">
+                                            <FontIcon Glyph="{x:Bind MonitorIconGlyph, Mode=OneWay}"
+                                                      FontSize="20"
+                                                      VerticalAlignment="Center"
+                                                      HorizontalAlignment="Center" />
+                                            <TextBlock Text="{x:Bind Name, Mode=OneWay}"
+                                                      FontSize="20"
+                                                      FontWeight="SemiBold"
+                                                      VerticalAlignment="Center" />
+                                        </StackPanel>
+
+                                                    <!-- Brightness Control -->
+                                                    <Grid Height="40" HorizontalAlignment="Stretch">
+                                                        <Grid.ColumnDefinitions>
+                                                            <ColumnDefinition Width="1*"/>
+                                                            <ColumnDefinition Width="7*"/>
+                                                            <ColumnDefinition Width="2*"/>
+                                                        </Grid.ColumnDefinitions>
+
+                                                        <FontIcon Grid.Column="0"
+                                                                 Glyph="&#xE793;"
+                                                                 FontSize="14"
+                                                                 VerticalAlignment="Center"
+                                                                 HorizontalAlignment="Center" />
+
+                                                        <Slider Grid.Column="1"
+                                                               HorizontalAlignment="Stretch"
+                                                               MinHeight="32"
+                                                               VerticalAlignment="Center"
+                                                               Margin="0,2"
+                                                               Minimum="{x:Bind MinBrightness, Mode=OneWay}"
+                                                               Maximum="{x:Bind MaxBrightness, Mode=OneWay}"
+                                                               Value="{x:Bind Brightness, Mode=OneWay}"
+                                                               ValueChanged="Slider_ValueChanged"
+                                                               PointerCaptureLost="Slider_PointerCaptureLost"
+                                                               Tag="Brightness"
+                                                               IsEnabled="{x:Bind IsInteractionEnabled, Mode=OneWay}" />
+
+                                                        <TextBlock Grid.Column="2"
+                                                                  FontSize="12"
+                                                                  FontWeight="SemiBold"
+                                                                  HorizontalAlignment="Center"
+                                                                  VerticalAlignment="Center"
+                                                                  Text="{x:Bind Brightness, Mode=OneWay}" />
+                                                    </Grid>
+
+                                                    <!-- Color Temperature Control -->
+                                                    <Grid Height="40"
+                                                          HorizontalAlignment="Stretch"
+                                                          Visibility="{x:Bind ConvertBoolToVisibility(ShowColorTemperature), Mode=OneWay}">
+                                                        <Grid.Transitions>
+                                                            <TransitionCollection>
+                                                                <EntranceThemeTransition FromVerticalOffset="10" />
+                                                                <RepositionThemeTransition />
+                                                            </TransitionCollection>
+                                                        </Grid.Transitions>
+                                                        <Grid.ColumnDefinitions>
+                                                            <ColumnDefinition Width="1*"/>
+                                                            <ColumnDefinition Width="7*"/>
+                                                            <ColumnDefinition Width="2*"/>
+                                                        </Grid.ColumnDefinitions>
+
+                                                        <FontIcon Grid.Column="0"
+                                                                 Glyph="&#xE790;"
+                                                                 FontSize="14"
+                                                                 VerticalAlignment="Center"
+                                                                 HorizontalAlignment="Center" />
+
+                                                        <Slider Grid.Column="1"
+                                                               HorizontalAlignment="Stretch"
+                                                               MinHeight="32"
+                                                               VerticalAlignment="Center"
+                                                               Margin="0,2"
+                                                               Minimum="0"
+                                                               Maximum="100"
+                                                               Value="{x:Bind ColorTemperaturePercent, Mode=OneWay}"
+                                                               ValueChanged="Slider_ValueChanged"
+                                                               PointerCaptureLost="Slider_PointerCaptureLost"
+                                                               Tag="ColorTemperature"
+                                                               IsEnabled="{x:Bind IsInteractionEnabled, Mode=OneWay}" />
+
+                                                        <TextBlock Grid.Column="2"
+                                                                  FontSize="12"
+                                                                  FontWeight="SemiBold"
+                                                                  HorizontalAlignment="Center"
+                                                                  VerticalAlignment="Center">
+                                                            <Run Text="{x:Bind ColorTemperature, Mode=OneWay}" />
+                                                            <Run Text="K" FontSize="9" />
+                                                        </TextBlock>
+                                                    </Grid>
+
+                                                    <!-- Contrast Control -->
+                                                    <Grid Height="40"
+                                                          HorizontalAlignment="Stretch"
+                                                          Visibility="{x:Bind ConvertBoolToVisibility(ShowContrast), Mode=OneWay}">
+                                                        <Grid.Transitions>
+                                                            <TransitionCollection>
+                                                                <EntranceThemeTransition FromVerticalOffset="10" />
+                                                                <RepositionThemeTransition />
+                                                            </TransitionCollection>
+                                                        </Grid.Transitions>
+                                                        <Grid.ColumnDefinitions>
+                                                            <ColumnDefinition Width="1*"/>
+                                                            <ColumnDefinition Width="7*"/>
+                                                            <ColumnDefinition Width="2*"/>
+                                                        </Grid.ColumnDefinitions>
+
+                                                        <FontIcon Grid.Column="0"
+                                                                 Glyph="&#xE7A6;"
+                                                                 FontSize="14"
+                                                                 VerticalAlignment="Center"
+                                                                 HorizontalAlignment="Center" />
+
+                                                        <Slider Grid.Column="1"
+                                                               HorizontalAlignment="Stretch"
+                                                               MinHeight="32"
+                                                               VerticalAlignment="Center"
+                                                               Margin="0,2"
+                                                               Minimum="0"
+                                                               Maximum="100"
+                                                               Value="{x:Bind ContrastPercent, Mode=OneWay}"
+                                                               ValueChanged="Slider_ValueChanged"
+                                                               PointerCaptureLost="Slider_PointerCaptureLost"
+                                                               Tag="Contrast"
+                                                               IsEnabled="{x:Bind IsInteractionEnabled, Mode=OneWay}" />
+
+                                                        <TextBlock Grid.Column="2"
+                                                                  FontSize="12"
+                                                                  FontWeight="SemiBold"
+                                                                  HorizontalAlignment="Center"
+                                                                  VerticalAlignment="Center">
+                                                            <Run Text="{x:Bind Contrast, Mode=OneWay}" />
+                                                            <Run Text="%" FontSize="9" />
+                                                        </TextBlock>
+                                                    </Grid>
+
+                                                    <!-- Volume Control -->
+                                                    <Grid Height="40"
+                                                          HorizontalAlignment="Stretch"
+                                                          Visibility="{x:Bind ConvertBoolToVisibility(ShowVolume), Mode=OneWay}">
+                                                        <Grid.Transitions>
+                                                            <TransitionCollection>
+                                                                <EntranceThemeTransition FromVerticalOffset="10" />
+                                                                <RepositionThemeTransition />
+                                                            </TransitionCollection>
+                                                        </Grid.Transitions>
+                                                        <Grid.ColumnDefinitions>
+                                                            <ColumnDefinition Width="1*"/>
+                                                            <ColumnDefinition Width="7*"/>
+                                                            <ColumnDefinition Width="2*"/>
+                                                        </Grid.ColumnDefinitions>
+
+                                                        <FontIcon Grid.Column="0"
+                                                                 Glyph="&#xE767;"
+                                                                 FontSize="14"
+                                                                 VerticalAlignment="Center"
+                                                                 HorizontalAlignment="Center" />
+
+                                                        <Slider Grid.Column="1"
+                                                               HorizontalAlignment="Stretch"
+                                                               MinHeight="32"
+                                                               VerticalAlignment="Center"
+                                                               Margin="0,2"
+                                                               Minimum="{x:Bind MinVolume, Mode=OneWay}"
+                                                               Maximum="{x:Bind MaxVolume, Mode=OneWay}"
+                                                               Value="{x:Bind Volume, Mode=OneWay}"
+                                                               ValueChanged="Slider_ValueChanged"
+                                                               PointerCaptureLost="Slider_PointerCaptureLost"
+                                                               Tag="Volume"
+                                                               IsEnabled="{x:Bind IsInteractionEnabled, Mode=OneWay}" />
+
+                                                        <TextBlock Grid.Column="2"
+                                                                  FontSize="12"
+                                                                  FontWeight="SemiBold"
+                                                                  HorizontalAlignment="Center"
+                                                                  VerticalAlignment="Center">
+                                                            <Run Text="{x:Bind Volume, Mode=OneWay}" />
+                                                            <Run Text="%" FontSize="9" />
+                                                        </TextBlock>
+                                                    </Grid>
+
+                                    </StackPanel>
+                                </DataTemplate>
+                            </ItemsControl.ItemTemplate>
+                        </ItemsControl>
+                    </StackPanel>
+                </ScrollViewer>
+
+                <!-- Status Bar with modern design -->
+                <Grid Grid.Row="1"
+                      BorderBrush="{ThemeResource DividerStrokeColorDefaultBrush}"
+                      BorderThickness="0,1,0,0"
+                      Padding="8">
+                    <Grid.ColumnDefinitions>
+                        <ColumnDefinition Width="*" />
+                        <ColumnDefinition Width="Auto" />
+                    </Grid.ColumnDefinitions>
+
+                    <!-- Status Information -->
+                    <StackPanel Orientation="Vertical" VerticalAlignment="Center">
+                        <TextBlock x:Name="AdjustBrightnessTextBlock"
+                                  FontSize="16"
+                                  FontWeight="SemiBold" />
+                    </StackPanel>
+
+                    <!-- Action Buttons -->
+                    <StackPanel Grid.Column="1"
+                               Orientation="Horizontal"
+                               Spacing="4"
+                               VerticalAlignment="Center">
+                        <Button x:Name="LinkButton"
+                               Width="40"
+                               Height="40"
+                               CornerRadius="4"
+                               Background="Transparent"
+                               BorderThickness="0"
+                               ToolTipService.ToolTip="Sync all monitors">
+                            <FontIcon Glyph="&#xE71B;" FontSize="16" />
+                        </Button>
+                        <Button x:Name="DisableButton"
+                               Width="40"
+                               Height="40"
+                               CornerRadius="4"
+                               Background="Transparent"
+                               BorderThickness="0"
+                               ToolTipService.ToolTip="Toggle control">
+                            <FontIcon Glyph="&#xE7E8;" FontSize="16" />
+                        </Button>
+                        <Button x:Name="RefreshButton"
+                               Width="40"
+                               Height="40"
+                               CornerRadius="4"
+                               Background="Transparent"
+                               BorderThickness="0"
+                               ToolTipService.ToolTip="Refresh monitors">
+                            <FontIcon Glyph="&#xE72C;" FontSize="16" />
+                        </Button>
+                    </StackPanel>
+                </Grid>
+            </Grid>
+        </Border>
+    </Grid>
+</Window>

src/modules/powerdisplay/PowerDisplay/PowerDisplayXAML/MainWindow.xaml.cs

@@ -0,0 +1,793 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Threading.Tasks;
+using ManagedCommon;
+using Microsoft.PowerToys.Settings.UI.Library;
+using Microsoft.UI;
+using Microsoft.UI.Composition;
+using Microsoft.UI.Windowing;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Media;
+using Microsoft.UI.Xaml.Media.Animation;
+using PowerDisplay.Core;
+using PowerDisplay.Core.Interfaces;
+using PowerDisplay.Core.Models;
+using PowerDisplay.Helpers;
+using PowerDisplay.Native;
+using PowerDisplay.ViewModels;
+using Windows.Graphics;
+using WinRT.Interop;
+using static PowerDisplay.Native.PInvoke;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay
+{
+    /// <summary>
+    /// PowerDisplay main window
+    /// </summary>
+    [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicProperties | DynamicallyAccessedMemberTypes.PublicMethods)]
+    public sealed partial class MainWindow : Window, IDisposable
+    {
+        private readonly ISettingsUtils _settingsUtils = new SettingsUtils();
+        private MainViewModel _viewModel = null!;
+        private TrayIconHelper _trayIcon = null!;
+        private AppWindow _appWindow = null!;
+        private bool _isExiting;
+
+        // Expose ViewModel as property for x:Bind
+        public MainViewModel ViewModel => _viewModel;
+
+        // Conversion functions for x:Bind (AOT-compatible alternative to converters)
+        public Visibility ConvertBoolToVisibility(bool value) => value ? Visibility.Visible : Visibility.Collapsed;
+
+        public MainWindow()
+        {
+            try
+            {
+                this.InitializeComponent();
+
+                // Lightweight initialization - no heavy operations in constructor
+                // Setup window properties
+                SetupWindow();
+
+                // Initialize tray icon
+                InitializeTrayIcon();
+
+                // Initialize UI text
+                InitializeUIText();
+
+                // Clean up resources on window close
+                this.Closed += OnWindowClosed;
+
+                // Delay ViewModel creation until first activation (async)
+                this.Activated += OnFirstActivated;
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"MainWindow initialization failed: {ex.Message}");
+                ShowError($"Unable to start main window: {ex.Message}");
+            }
+        }
+
+        private bool _hasInitialized;
+
+        private async void OnFirstActivated(object sender, WindowActivatedEventArgs args)
+        {
+            // Only initialize once on first activation
+            if (_hasInitialized)
+            {
+                return;
+            }
+
+            _hasInitialized = true;
+            this.Activated -= OnFirstActivated; // Unsubscribe after first run
+
+            // Create and initialize ViewModel asynchronously
+            // This will trigger Loading UI (IsScanning) during monitor discovery
+            _viewModel = new MainViewModel();
+            RootGrid.DataContext = _viewModel;
+
+            // Notify bindings that ViewModel is now available (for x:Bind)
+            Bindings.Update();
+
+            // Initialize ViewModel event handlers
+            _viewModel.UIRefreshRequested += OnUIRefreshRequested;
+            _viewModel.Monitors.CollectionChanged += OnMonitorsCollectionChanged;
+            _viewModel.PropertyChanged += OnViewModelPropertyChanged;
+
+            // Bind button events
+            LinkButton.Click += OnLinkClick;
+            DisableButton.Click += OnDisableClick;
+            RefreshButton.Click += OnRefreshClick;
+
+            // Start async initialization (monitor scanning happens here)
+            await InitializeAsync();
+
+            // Hide window after initialization completes
+            HideWindow();
+        }
+
+        private async Task InitializeAsync()
+        {
+            try
+            {
+                // No delays! Direct async operation
+                await _viewModel.RefreshMonitorsAsync();
+                await _viewModel.ReloadMonitorSettingsAsync();
+
+                // Adjust window size after data is loaded (event-driven)
+                AdjustWindowSizeToContent();
+            }
+            catch (WmiLight.WmiException ex)
+            {
+                Logger.LogError($"WMI access failed: {ex.Message}");
+                ShowError("Unable to access internal display control, administrator privileges may be required.");
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Initialization failed: {ex.Message}");
+                ShowError($"Initialization failed: {ex.Message}");
+            }
+        }
+
+        private void InitializeUIText()
+        {
+            try
+            {
+                var loader = ResourceLoaderInstance.ResourceLoader;
+
+                // Set text block content
+                ScanningMonitorsTextBlock.Text = loader.GetString("ScanningMonitorsText");
+                NoMonitorsTextBlock.Text = loader.GetString("NoMonitorsText");
+                AdjustBrightnessTextBlock.Text = loader.GetString("AdjustBrightnessText");
+
+                // Set button tooltips
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(LinkButton, loader.GetString("SyncAllMonitorsTooltip"));
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(DisableButton, loader.GetString("ToggleControlTooltip"));
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(RefreshButton, loader.GetString("RefreshTooltip"));
+            }
+            catch (Exception ex)
+            {
+                // Use English defaults if resource loading fails
+                Logger.LogWarning($"Failed to load localized strings: {ex.Message}");
+                ScanningMonitorsTextBlock.Text = "Scanning monitors...";
+                NoMonitorsTextBlock.Text = "No monitors detected";
+                AdjustBrightnessTextBlock.Text = "PowerDisplay";
+
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(LinkButton, "Synchronize all monitors to the same brightness");
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(DisableButton, "Enable or disable brightness control");
+                Microsoft.UI.Xaml.Controls.ToolTipService.SetToolTip(RefreshButton, "Rescan connected monitors");
+            }
+        }
+
+        private void ShowError(string message)
+        {
+            if (_viewModel != null)
+            {
+                _viewModel.StatusText = $"Error: {message}";
+            }
+            else
+            {
+                Logger.LogError($"Error (ViewModel not yet initialized): {message}");
+            }
+        }
+
+        private void OnWindowClosed(object sender, WindowEventArgs args)
+        {
+            // Allow window to close if program is exiting
+            if (_isExiting)
+            {
+                // Clean up event subscriptions
+                if (_viewModel != null)
+                {
+                    _viewModel.UIRefreshRequested -= OnUIRefreshRequested;
+                    _viewModel.Monitors.CollectionChanged -= OnMonitorsCollectionChanged;
+                    _viewModel.PropertyChanged -= OnViewModelPropertyChanged;
+                }
+
+                args.Handled = false;
+                return;
+            }
+
+            // If only user operation (although we hide close button), just hide window
+            args.Handled = true; // Prevent window closing
+            HideWindow();
+        }
+
+        private void InitializeTrayIcon()
+        {
+            _trayIcon = new TrayIconHelper(this);
+            _trayIcon.SetCallbacks(
+                onShow: ShowWindow,
+                onExit: ExitApplication,
+                onRefresh: () => _viewModel?.RefreshCommand?.Execute(null),
+                onSettings: OpenSettings);
+        }
+
+        private void OpenSettings()
+        {
+            try
+            {
+                // Open PowerToys Settings to PowerDisplay page
+                PowerDisplay.Helpers.SettingsDeepLink.OpenPowerDisplaySettings();
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Failed to open settings: {ex.Message}");
+            }
+        }
+
+        private void ShowWindow()
+        {
+            var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
+
+            // Adjust window size before showing
+            AdjustWindowSizeToContent();
+
+            // Reposition to bottom right (set position before showing)
+            if (_appWindow != null)
+            {
+                PositionWindowAtBottomRight(_appWindow);
+            }
+
+            // Set initial state for animation
+            RootGrid.Opacity = 0;
+
+            // Show window
+            WindowHelper.ShowWindow(hWnd, true);
+
+            // Bring window to foreground
+            PInvoke.SetForegroundWindow(hWnd);
+
+            // Use storyboard animation for window entrance
+            if (RootGrid.Resources.ContainsKey("SlideInStoryboard"))
+            {
+                var slideInStoryboard = RootGrid.Resources["SlideInStoryboard"] as Storyboard;
+                slideInStoryboard?.Begin();
+            }
+        }
+
+        private void HideWindow()
+        {
+            var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
+
+            // Use storyboard animation for window exit
+            if (RootGrid.Resources.ContainsKey("SlideOutStoryboard"))
+            {
+                var slideOutStoryboard = RootGrid.Resources["SlideOutStoryboard"] as Storyboard;
+                if (slideOutStoryboard != null)
+                {
+                    slideOutStoryboard.Completed += (s, e) =>
+                    {
+                        // Hide window after animation completes
+                        WindowHelper.ShowWindow(hWnd, false);
+                    };
+                    slideOutStoryboard.Begin();
+                }
+            }
+            else
+            {
+                // Fallback: hide immediately if animation not found
+                WindowHelper.ShowWindow(hWnd, false);
+            }
+        }
+
+        private async void OnUIRefreshRequested(object? sender, EventArgs e)
+        {
+            Logger.LogInfo("UI refresh requested due to settings change");
+            await _viewModel.ReloadMonitorSettingsAsync();
+
+            // Adjust window size after settings are reloaded (no delay needed!)
+            DispatcherQueue.TryEnqueue(() => AdjustWindowSizeToContent());
+        }
+
+        private void OnMonitorsCollectionChanged(object? sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
+        {
+            // Adjust window size when monitors collection changes (event-driven!)
+            // The UI binding will update first, then we adjust size
+            DispatcherQueue.TryEnqueue(Microsoft.UI.Dispatching.DispatcherQueuePriority.Low, () =>
+            {
+                AdjustWindowSizeToContent();
+            });
+        }
+
+        private void OnViewModelPropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e)
+        {
+            // Adjust window size when relevant properties change (event-driven!)
+            if (e.PropertyName == nameof(_viewModel.IsScanning) ||
+                e.PropertyName == nameof(_viewModel.HasMonitors) ||
+                e.PropertyName == nameof(_viewModel.ShowNoMonitorsMessage))
+            {
+                // Use Low priority to ensure UI bindings update first
+                DispatcherQueue.TryEnqueue(Microsoft.UI.Dispatching.DispatcherQueuePriority.Low, () =>
+                {
+                    AdjustWindowSizeToContent();
+                });
+            }
+        }
+
+        /// <summary>
+        /// Set exit flag to allow window to close normally
+        /// </summary>
+        public void SetExiting()
+        {
+            _isExiting = true;
+        }
+
+        /// <summary>
+        /// 快速关闭窗口，跳过动画和复杂清理
+        /// </summary>
+        public void FastShutdown()
+        {
+            try
+            {
+                _isExiting = true;
+
+                // 立即释放托盘图标
+                _trayIcon?.Dispose();
+
+                // 快速清理 ViewModel
+                if (_viewModel != null)
+                {
+                    // 取消事件订阅
+                    _viewModel.UIRefreshRequested -= OnUIRefreshRequested;
+                    _viewModel.Monitors.CollectionChanged -= OnMonitorsCollectionChanged;
+                    _viewModel.PropertyChanged -= OnViewModelPropertyChanged;
+
+                    // 立即释放
+                    _viewModel.Dispose();
+                }
+
+                // 直接关闭窗口，不等待动画
+                var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
+                WindowHelper.ShowWindow(hWnd, false);
+            }
+            catch (Exception ex)
+            {
+                // 忽略清理错误，确保能够关闭
+                Logger.LogWarning($"FastShutdown error: {ex.Message}");
+            }
+        }
+
+        private void ExitApplication()
+        {
+            try
+            {
+                // 使用快速关闭
+                FastShutdown();
+
+                // 直接调用应用程序快速退出
+                if (Application.Current is App app)
+                {
+                    app.Shutdown();
+                }
+
+                // 确保立即退出
+                Environment.Exit(0);
+            }
+            catch (Exception ex)
+            {
+                // 确保能够退出
+                Logger.LogError($"ExitApplication error: {ex.Message}");
+                Environment.Exit(0);
+            }
+        }
+
+        private async void OnRefreshClick(object sender, RoutedEventArgs e)
+        {
+            try
+            {
+                // Add button press animation
+                if (sender is Button button)
+                {
+                    await AnimateButtonPress(button);
+                }
+
+                // Refresh monitor list
+                if (_viewModel?.RefreshCommand?.CanExecute(null) == true)
+                {
+                    _viewModel.RefreshCommand.Execute(null);
+
+                    // Window size will be adjusted automatically by OnMonitorsCollectionChanged event!
+                    // No delay needed - event-driven design
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"OnRefreshClick failed: {ex}");
+                if (_viewModel != null)
+                {
+                    _viewModel.StatusText = "Refresh failed";
+                }
+            }
+        }
+
+        private async void OnLinkClick(object sender, RoutedEventArgs e)
+        {
+            try
+            {
+                // Add button press animation
+                if (sender is Button button)
+                {
+                    await AnimateButtonPress(button);
+                }
+
+                // Link all monitor brightness (synchronized adjustment)
+                if (_viewModel != null && _viewModel.Monitors.Count > 0)
+                {
+                    // Get first monitor brightness as reference
+                    var baseBrightness = _viewModel.Monitors.First().Brightness;
+                    _ = _viewModel.SetAllBrightnessAsync(baseBrightness);
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"OnLinkClick failed: {ex}");
+            }
+        }
+
+        private async void OnDisableClick(object sender, RoutedEventArgs e)
+        {
+            try
+            {
+                // Add button press animation
+                if (sender is Button button)
+                {
+                    await AnimateButtonPress(button);
+                }
+
+                // Disable/enable all monitor controls
+                if (_viewModel != null)
+                {
+                    foreach (var monitor in _viewModel.Monitors)
+                    {
+                        monitor.IsAvailable = !monitor.IsAvailable;
+                    }
+
+                    _viewModel.StatusText = _viewModel.Monitors.Any(m => m.IsAvailable)
+                        ? "Display control enabled"
+                        : "Display control disabled";
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"OnDisableClick failed: {ex}");
+            }
+        }
+
+        /// <summary>
+        /// Get internal monitor name, consistent with SettingsManager logic
+        /// </summary>
+        private async void OnTestClick(object sender, RoutedEventArgs e)
+        {
+            ContentDialog? dlg = null;
+            Core.MonitorManager? manager = null;
+
+            try
+            {
+                // Test monitor discovery functionality
+                dlg = new ContentDialog
+                {
+                    Title = "Monitor Detection Test",
+                    Content = "Starting monitor detection...",
+                    CloseButtonText = "Close",
+                    XamlRoot = this.Content.XamlRoot,
+                };
+
+                _ = dlg.ShowAsync();
+
+                manager = new Core.MonitorManager();
+                var monitors = await manager.DiscoverMonitorsAsync(default(System.Threading.CancellationToken));
+
+                string message = $"Found {monitors.Count} monitors:\n\n";
+                foreach (var monitor in monitors)
+                {
+                    message += $"• {monitor.Name}\n";
+                    message += $"  Type: {monitor.Type}\n";
+                    message += $"  Brightness: {monitor.CurrentBrightness}%\n\n";
+                }
+
+                if (monitors.Count == 0)
+                {
+                    message = "No monitors found.\n\n";
+                    message += "Possible reasons:\n";
+                    message += "• DDC/CI not supported\n";
+                    message += "• Driver issues\n";
+                    message += "• Permission issues\n";
+                    message += "• Cable doesn't support DDC/CI";
+                }
+
+                dlg.Content = message;
+
+                // Don't dispose manager, use existing manager
+                // Initialize ViewModel and bind to root Grid refresh
+                if (monitors.Count > 0)
+                {
+                    // Use existing refresh command
+                    await _viewModel.RefreshMonitorsAsync();
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"OnTestClick failed: {ex}");
+                if (dlg != null)
+                {
+                    dlg.Content = $"Error: {ex.Message}\n\nType: {ex.GetType().Name}";
+                }
+            }
+            finally
+            {
+                manager?.Dispose();
+            }
+        }
+
+        private void SetupWindow()
+        {
+            try
+            {
+                // Get window handle
+                var hWnd = WindowNative.GetWindowHandle(this);
+                var windowId = Win32Interop.GetWindowIdFromWindow(hWnd);
+                _appWindow = AppWindow.GetFromWindowId(windowId);
+
+                if (_appWindow != null)
+                {
+                    // Set initial window size - will be adjusted later based on content
+                    _appWindow.Resize(new SizeInt32 { Width = 640, Height = 480 });
+
+                    // Position window at bottom right corner
+                    PositionWindowAtBottomRight(_appWindow);
+
+                    // Set window icon and title bar
+                    _appWindow.Title = "PowerDisplay";
+
+                    // Remove title bar and system buttons
+                    var presenter = _appWindow.Presenter as OverlappedPresenter;
+                    if (presenter != null)
+                    {
+                        // Disable resizing
+                        presenter.IsResizable = false;
+
+                        // Disable maximize button
+                        presenter.IsMaximizable = false;
+
+                        // Disable minimize button
+                        presenter.IsMinimizable = false;
+
+                        // Set borderless mode
+                        presenter.SetBorderAndTitleBar(false, false);
+                    }
+
+                    // Custom title bar - completely remove all buttons
+                    var titleBar = _appWindow.TitleBar;
+                    if (titleBar != null)
+                    {
+                        // Extend content into title bar area
+                        titleBar.ExtendsContentIntoTitleBar = true;
+
+                        // Completely remove title bar height
+                        titleBar.PreferredHeightOption = Microsoft.UI.Windowing.TitleBarHeightOption.Collapsed;
+
+                        // Set all button colors to transparent
+                        titleBar.ButtonBackgroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonInactiveBackgroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonForegroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonHoverBackgroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonHoverForegroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonPressedBackgroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonPressedForegroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+                        titleBar.ButtonInactiveForegroundColor = Windows.UI.Color.FromArgb(0, 0, 0, 0);
+
+                        // Disable title bar interaction area
+                        titleBar.SetDragRectangles(Array.Empty<Windows.Graphics.RectInt32>());
+                    }
+
+                    // Set modern Mica Alt backdrop for Windows 11
+                    try
+                    {
+                        // Use Mica Alt for a more modern appearance
+                        if (Microsoft.UI.Composition.SystemBackdrops.MicaController.IsSupported())
+                        {
+                            this.SystemBackdrop = new Microsoft.UI.Xaml.Media.MicaBackdrop();
+                        }
+                        else
+                        {
+                            // Fallback to basic backdrop for older systems
+                            this.SystemBackdrop = new Microsoft.UI.Xaml.Media.DesktopAcrylicBackdrop();
+                        }
+                    }
+                    catch
+                    {
+                        // Fallback: use solid color background
+                        this.SystemBackdrop = null;
+                    }
+
+                    // Use Win32 API to further disable window moving
+                    WindowHelper.DisableWindowMovingAndResizing(hWnd);
+
+                    // Hide window from taskbar
+                    WindowHelper.HideFromTaskbar(hWnd);
+
+                    // Optional: set window topmost
+                    // WindowHelper.SetWindowTopmost(hWnd, true);
+                }
+            }
+            catch (Exception ex)
+            {
+                // Ignore window setup errors
+                Logger.LogWarning($"Window setup error: {ex.Message}");
+            }
+        }
+
+        private void AdjustWindowSizeToContent()
+        {
+            try
+            {
+                if (_appWindow == null || RootGrid == null)
+                {
+                    return;
+                }
+
+                // Force layout update to ensure proper measurement
+                RootGrid.UpdateLayout();
+
+                // Get precise content height
+                var availableWidth = 640.0;
+                var contentHeight = GetContentHeight(availableWidth);
+
+                // Account for display scaling
+                var scale = RootGrid.XamlRoot?.RasterizationScale ?? 1.0;
+                var scaledHeight = (int)Math.Ceiling(contentHeight * scale);
+
+                // Only set maximum height for scrollable content
+                scaledHeight = Math.Min(scaledHeight, 650);
+
+                // Check if resize is needed
+                var currentSize = _appWindow.Size;
+                if (Math.Abs(currentSize.Height - scaledHeight) > 1)
+                {
+                    Logger.LogInfo($"Adjusting window height from {currentSize.Height} to {scaledHeight} (content: {contentHeight})");
+                    _appWindow.Resize(new SizeInt32 { Width = 640, Height = scaledHeight });
+
+                    // Update clip region to match new window size
+                    UpdateClipRegion(640, scaledHeight / scale);
+
+                    // Reposition to maintain bottom-right position
+                    PositionWindowAtBottomRight(_appWindow);
+                }
+            }
+            catch (Exception ex)
+            {
+                Logger.LogError($"Error adjusting window size: {ex.Message}");
+            }
+        }
+
+        private double GetContentHeight(double availableWidth)
+        {
+            // Try to measure MainContainer directly for precise content size
+            if (RootGrid.FindName("MainContainer") is Border mainContainer)
+            {
+                mainContainer.Measure(new Windows.Foundation.Size(availableWidth, double.PositiveInfinity));
+                return mainContainer.DesiredSize.Height;
+            }
+
+            // Fallback: Measure the root grid
+            RootGrid.Measure(new Windows.Foundation.Size(availableWidth, double.PositiveInfinity));
+            return RootGrid.DesiredSize.Height + 4; // Small padding for fallback method
+        }
+
+        private void UpdateClipRegion(double width, double height)
+        {
+            // Clip region removed to allow automatic sizing
+            // No longer needed as we removed the fixed clip from RootGrid
+        }
+
+        private void PositionWindowAtBottomRight(AppWindow appWindow)
+        {
+            try
+            {
+                // Get display area
+                var displayArea = DisplayArea.GetFromWindowId(appWindow.Id, DisplayAreaFallback.Nearest);
+                if (displayArea != null)
+                {
+                    var workArea = displayArea.WorkArea;
+                    var windowSize = appWindow.Size;
+
+                    // Calculate bottom-right position, close to taskbar
+                    // WorkArea already excludes taskbar area, so use WorkArea bottom directly
+                    int rightMargin = 10; // Small margin from right edge
+                    int x = workArea.Width - windowSize.Width - rightMargin;
+                    int y = workArea.Height - windowSize.Height; // Close to taskbar top, no gap
+
+                    // Move window to bottom right
+                    appWindow.Move(new PointInt32 { X = x, Y = y });
+                }
+            }
+            catch (Exception ex)
+            {
+                // Ignore errors when positioning window
+                Logger.LogDebug($"Failed to position window: {ex.Message}");
+            }
+        }
+
+        /// <summary>
+        /// Animates button press for modern interaction feedback
+        /// </summary>
+        /// <param name="button">The button to animate</param>
+        private async Task AnimateButtonPress(Button button)
+        {
+            // Button animation disabled to avoid compilation errors
+            // Using default button visual states instead
+            await Task.CompletedTask;
+        }
+
+        /// <summary>
+        /// Slider ValueChanged event handler - does nothing during drag
+        /// This allows the slider UI to update smoothly without triggering hardware operations
+        /// </summary>
+        private void Slider_ValueChanged(object sender, Microsoft.UI.Xaml.Controls.Primitives.RangeBaseValueChangedEventArgs e)
+        {
+            // During drag, this event fires 60-120 times per second
+            // We intentionally do nothing here to keep UI smooth
+            // The actual ViewModel update happens in PointerCaptureLost after drag completes
+        }
+
+        /// <summary>
+        /// Slider PointerCaptureLost event handler - updates ViewModel when drag completes
+        /// This is the WinUI3 recommended way to detect drag completion
+        /// </summary>
+        private void Slider_PointerCaptureLost(object sender, Microsoft.UI.Xaml.Input.PointerRoutedEventArgs e)
+        {
+            var slider = sender as Slider;
+            if (slider == null)
+            {
+                return;
+            }
+
+            var propertyName = slider.Tag as string;
+            var monitorVm = slider.DataContext as MonitorViewModel;
+
+            if (monitorVm == null || propertyName == null)
+            {
+                return;
+            }
+
+            // Get final value after drag completes
+            int finalValue = (int)slider.Value;
+
+            // Now update the ViewModel, which will trigger hardware operation
+            switch (propertyName)
+            {
+                case "Brightness":
+                    monitorVm.Brightness = finalValue;
+                    Logger.LogDebug($"[UI] Brightness drag completed: {finalValue}");
+                    break;
+                case "ColorTemperature":
+                    monitorVm.ColorTemperaturePercent = finalValue;
+                    Logger.LogDebug($"[UI] ColorTemperature drag completed: {finalValue}%");
+                    break;
+                case "Contrast":
+                    monitorVm.ContrastPercent = finalValue;
+                    Logger.LogDebug($"[UI] Contrast drag completed: {finalValue}%");
+                    break;
+                case "Volume":
+                    monitorVm.Volume = finalValue;
+                    Logger.LogDebug($"[UI] Volume drag completed: {finalValue}");
+                    break;
+            }
+        }
+
+        public void Dispose()
+        {
+            _viewModel?.Dispose();
+            _trayIcon?.Dispose();
+            GC.SuppressFinalize(this);
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Program.cs

@@ -0,0 +1,59 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Threading;
+using ManagedCommon;
+using Microsoft.UI.Dispatching;
+using Microsoft.Windows.AppLifecycle;
+
+namespace PowerDisplay
+{
+    public static class Program
+    {
+        [STAThread]
+        public static void Main(string[] args)
+        {
+            Logger.InitializeLogger("\\PowerDisplay\\Logs");
+
+            WinRT.ComWrappersSupport.InitializeComWrappers();
+
+            // Parse command line arguments: args[0] = runner_pid, args[1] = pipe_uuid
+            int runnerPid = -1;
+            string pipeUuid = string.Empty;
+
+            if (args.Length >= 2)
+            {
+                if (int.TryParse(args[0], out int parsedPid))
+                {
+                    runnerPid = parsedPid;
+                }
+
+                pipeUuid = args[1];
+                Logger.LogInfo($"PowerDisplay started with runner_pid={runnerPid}, pipe_uuid={pipeUuid}");
+            }
+            else
+            {
+                Logger.LogWarning("PowerDisplay started without command line arguments");
+                Logger.LogWarning($"PowerDisplay started with insufficient arguments (expected 2, got {args.Length}). Running in standalone mode.");
+            }
+
+            var instanceKey = AppInstance.FindOrRegisterForKey("PowerToys_PowerDisplay_Instance");
+
+            if (instanceKey.IsCurrent)
+            {
+                Microsoft.UI.Xaml.Application.Start((p) =>
+                {
+                    var context = new DispatcherQueueSynchronizationContext(DispatcherQueue.GetForCurrentThread());
+                    SynchronizationContext.SetSynchronizationContext(context);
+                    _ = new App(runnerPid, pipeUuid);
+                });
+            }
+            else
+            {
+                Logger.LogWarning("Another instance of PowerDisplay is running. Exiting.");
+            }
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Serialization/JsonSourceGenerationContext.cs

@@ -0,0 +1,76 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Microsoft.PowerToys.Settings.UI.Library;
+
+#pragma warning disable SA1402 // File may only contain a single type - Related JSON serialization types grouped together
+
+namespace PowerDisplay.Serialization
+{
+    /// <summary>
+    /// JSON source generation context for AOT compatibility.
+    /// Eliminates reflection-based JSON serialization.
+    /// </summary>
+    [JsonSerializable(typeof(PowerDisplayMonitorsIPCResponse))]
+    [JsonSerializable(typeof(MonitorInfoData))]
+    [JsonSerializable(typeof(IPCMessageAction))]
+    [JsonSerializable(typeof(MonitorStateFile))]
+    [JsonSerializable(typeof(MonitorStateEntry))]
+    [JsonSourceGenerationOptions(
+        WriteIndented = true,
+        PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
+        DefaultIgnoreCondition = JsonIgnoreCondition.Never)]
+    internal sealed partial class AppJsonContext : JsonSerializerContext
+    {
+    }
+
+    /// <summary>
+    /// IPC message wrapper for parsing action-based messages.
+    /// Used in App.xaml.cs for dynamic IPC command handling.
+    /// </summary>
+    internal sealed class IPCMessageAction
+    {
+        [JsonPropertyName("action")]
+        public string? Action { get; set; }
+    }
+
+    /// <summary>
+    /// Monitor state file structure for JSON persistence.
+    /// Made internal (from private) to support source generation.
+    /// </summary>
+    internal sealed class MonitorStateFile
+    {
+        [JsonPropertyName("monitors")]
+        public Dictionary<string, MonitorStateEntry> Monitors { get; set; } = new();
+
+        [JsonPropertyName("lastUpdated")]
+        public DateTime LastUpdated { get; set; }
+    }
+
+    /// <summary>
+    /// Individual monitor state entry.
+    /// Made internal (from private) to support source generation.
+    /// </summary>
+    internal sealed class MonitorStateEntry
+    {
+        [JsonPropertyName("brightness")]
+        public int Brightness { get; set; }
+
+        [JsonPropertyName("colorTemperature")]
+        public int ColorTemperature { get; set; }
+
+        [JsonPropertyName("contrast")]
+        public int Contrast { get; set; }
+
+        [JsonPropertyName("volume")]
+        public int Volume { get; set; }
+
+        [JsonPropertyName("lastUpdated")]
+        public DateTime LastUpdated { get; set; }
+    }
+}

src/modules/powerdisplay/PowerDisplay/Strings/en-us/Resources.resw

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <data name="ScanningMonitorsText" xml:space="preserve">
+    <value>Scanning monitors...</value>
+  </data>
+  <data name="NoMonitorsText" xml:space="preserve">
+    <value>No monitors detected</value>
+  </data>
+  <data name="AdjustBrightnessText" xml:space="preserve">
+    <value>PowerDisplay</value>
+  </data>
+  <data name="SyncAllMonitorsTooltip" xml:space="preserve">
+    <value>Synchronize all monitors to the same brightness</value>
+  </data>
+  <data name="ToggleControlTooltip" xml:space="preserve">
+    <value>Enable or disable brightness control</value>
+  </data>
+  <data name="RefreshTooltip" xml:space="preserve">
+    <value>Rescan connected monitors</value>
+  </data>
+</root>

src/modules/powerdisplay/PowerDisplay/Telemetry/Events/PowerDisplayStartEvent.cs

@@ -0,0 +1,18 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Diagnostics.Tracing;
+using Microsoft.PowerToys.Telemetry;
+using Microsoft.PowerToys.Telemetry.Events;
+
+namespace PowerDisplay.Telemetry.Events
+{
+    [EventData]
+    public class PowerDisplayStartEvent : EventBase, IEvent
+    {
+        public new string EventName => "PowerDisplay_Start";
+
+        public PartA_PrivTags PartA_PrivTags => PartA_PrivTags.ProductAndServiceUsage;
+    }
+}

src/modules/powerdisplay/PowerDisplay/ViewModels/MainViewModel.cs

@@ -0,0 +1,792 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
+using System.IO;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+using System.Windows.Input;
+using ManagedCommon;
+using Microsoft.PowerToys.Settings.UI.Library;
+using Microsoft.UI.Dispatching;
+using Microsoft.UI.Xaml;
+using PowerDisplay.Commands;
+using PowerDisplay.Core;
+using PowerDisplay.Core.Interfaces;
+using PowerDisplay.Core.Models;
+using PowerDisplay.Helpers;
+using PowerDisplay.Serialization;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay.ViewModels;
+
+/// <summary>
+/// Main ViewModel for the PowerDisplay application
+/// </summary>
+[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicProperties | DynamicallyAccessedMemberTypes.PublicMethods)]
+public partial class MainViewModel : INotifyPropertyChanged, IDisposable
+{
+    private readonly MonitorManager _monitorManager;
+    private readonly DispatcherQueue _dispatcherQueue;
+    private readonly CancellationTokenSource _cancellationTokenSource;
+    private readonly ISettingsUtils _settingsUtils;
+    private readonly MonitorStateManager _stateManager;
+    private FileSystemWatcher? _settingsWatcher;
+
+    private ObservableCollection<MonitorViewModel> _monitors;
+    private string _statusText;
+    private bool _isScanning;
+    private bool _isInitialized;
+    private bool _isLoading;
+
+    /// <summary>
+    /// Event triggered when UI refresh is requested due to settings changes
+    /// </summary>
+    public event EventHandler? UIRefreshRequested;
+
+    public MainViewModel()
+    {
+        _dispatcherQueue = DispatcherQueue.GetForCurrentThread();
+        _cancellationTokenSource = new CancellationTokenSource();
+        _monitors = new ObservableCollection<MonitorViewModel>();
+        _statusText = "Initializing...";
+        _isScanning = true;
+
+        // Initialize settings utils
+        _settingsUtils = new SettingsUtils();
+        _stateManager = new MonitorStateManager();
+
+        // Initialize the monitor manager
+        _monitorManager = new MonitorManager();
+
+        // Subscribe to events
+        _monitorManager.MonitorsChanged += OnMonitorsChanged;
+
+        // Setup settings file monitoring
+        SetupSettingsFileWatcher();
+
+        // Start initial discovery
+        _ = InitializeAsync();
+    }
+
+    public ObservableCollection<MonitorViewModel> Monitors
+    {
+        get => _monitors;
+        set
+        {
+            _monitors = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public string StatusText
+    {
+        get => _statusText;
+        set
+        {
+            _statusText = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public bool IsScanning
+    {
+        get => _isScanning;
+        set
+        {
+            _isScanning = value;
+            OnPropertyChanged();
+            OnPropertyChanged(nameof(HasMonitors));
+            OnPropertyChanged(nameof(ShowNoMonitorsMessage));
+            OnPropertyChanged(nameof(IsInteractionEnabled));
+        }
+    }
+
+    public bool HasMonitors => !IsScanning && Monitors.Count > 0;
+
+    public bool ShowNoMonitorsMessage => !IsScanning && Monitors.Count == 0;
+
+    public bool IsInitialized
+    {
+        get => _isInitialized;
+        private set
+        {
+            _isInitialized = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public bool IsLoading
+    {
+        get => _isLoading;
+        private set
+        {
+            _isLoading = value;
+            OnPropertyChanged();
+            OnPropertyChanged(nameof(IsInteractionEnabled));
+        }
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether gets whether user interaction is enabled (not loading or scanning)
+    /// </summary>
+    public bool IsInteractionEnabled => !IsLoading && !IsScanning;
+
+    public ICommand RefreshCommand => new RelayCommand(async () => await RefreshMonitorsAsync());
+
+    public ICommand SetAllBrightnessCommand => new RelayCommand<int?>(async (brightness) =>
+    {
+        if (brightness.HasValue)
+        {
+            await SetAllBrightnessAsync(brightness.Value);
+        }
+    });
+
+    private async Task InitializeAsync()
+    {
+        try
+        {
+            StatusText = "Scanning monitors...";
+            IsScanning = true;
+
+            // Discover monitors
+            var monitors = await _monitorManager.DiscoverMonitorsAsync(_cancellationTokenSource.Token);
+
+            // Update UI on the dispatcher thread
+            _dispatcherQueue.TryEnqueue(() =>
+            {
+                UpdateMonitorList(monitors);
+                IsScanning = false;
+                IsInitialized = true;
+
+                if (monitors.Count > 0)
+                {
+                    StatusText = $"Found {monitors.Count} monitors";
+                }
+                else
+                {
+                    StatusText = "No controllable monitors found";
+                }
+            });
+        }
+        catch (Exception ex)
+        {
+            _dispatcherQueue.TryEnqueue(() =>
+            {
+                StatusText = $"Scan failed: {ex.Message}";
+                IsScanning = false;
+            });
+        }
+    }
+
+    public async Task RefreshMonitorsAsync()
+    {
+        if (IsScanning)
+        {
+            return;
+        }
+
+        try
+        {
+            StatusText = "Refreshing monitor list...";
+            IsScanning = true;
+
+            var monitors = await _monitorManager.DiscoverMonitorsAsync(_cancellationTokenSource.Token);
+
+            _dispatcherQueue.TryEnqueue(() =>
+            {
+                UpdateMonitorList(monitors);
+                IsScanning = false;
+                StatusText = $"Found {monitors.Count} monitors";
+            });
+        }
+        catch (Exception ex)
+        {
+            _dispatcherQueue.TryEnqueue(() =>
+            {
+                StatusText = $"Refresh failed: {ex.Message}";
+                IsScanning = false;
+            });
+        }
+    }
+
+    private void UpdateMonitorList(IReadOnlyList<Monitor> monitors)
+    {
+        Monitors.Clear();
+
+        var colorTempTasks = new List<Task>();
+        foreach (var monitor in monitors)
+        {
+            var vm = new MonitorViewModel(monitor, _monitorManager, this);
+            Monitors.Add(vm);
+
+            // Asynchronously initialize color temperature for DDC/CI monitors
+            if (monitor.SupportsColorTemperature && monitor.Type == MonitorType.External)
+            {
+                var task = InitializeColorTemperatureSafeAsync(monitor.Id, vm);
+                colorTempTasks.Add(task);
+            }
+        }
+
+        OnPropertyChanged(nameof(HasMonitors));
+        OnPropertyChanged(nameof(ShowNoMonitorsMessage));
+
+        // Send monitor information to Settings UI via IPC
+        SendMonitorInfoToSettingsUI();
+
+        // Restore saved settings if enabled (async, don't block)
+        // Pass color temperature initialization tasks so we can wait for them if needed
+        _ = ReloadMonitorSettingsAsync(colorTempTasks);
+    }
+
+    public async Task SetAllBrightnessAsync(int brightness)
+    {
+        try
+        {
+            StatusText = $"Setting all monitors brightness to {brightness}%...";
+            await _monitorManager.SetAllBrightnessAsync(brightness, _cancellationTokenSource.Token);
+            StatusText = $"All monitors brightness set to {brightness}%";
+        }
+        catch (Exception ex)
+        {
+            StatusText = $"Failed to set brightness: {ex.Message}";
+        }
+    }
+
+    private void OnMonitorsChanged(object? sender, MonitorListChangedEventArgs e)
+    {
+        _dispatcherQueue.TryEnqueue(() =>
+        {
+            // Handle monitors being added or removed
+            if (e.AddedMonitors.Count > 0)
+            {
+                foreach (var monitor in e.AddedMonitors)
+                {
+                    var existingVm = GetMonitorViewModel(monitor.Id);
+                    if (existingVm == null)
+                    {
+                        var vm = new MonitorViewModel(monitor, _monitorManager, this);
+                        Monitors.Add(vm);
+                    }
+                }
+            }
+
+            if (e.RemovedMonitors.Count > 0)
+            {
+                foreach (var monitor in e.RemovedMonitors)
+                {
+                    var vm = GetMonitorViewModel(monitor.Id);
+                    if (vm != null)
+                    {
+                        Monitors.Remove(vm);
+                        vm.Dispose();
+                    }
+                }
+            }
+
+            StatusText = $"Monitor list updated ({Monitors.Count} total)";
+
+            // Send updated monitor list to Settings UI via IPC
+            SendMonitorInfoToSettingsUI();
+        });
+    }
+
+    private MonitorViewModel? GetMonitorViewModel(string monitorId)
+    {
+        foreach (var vm in Monitors)
+        {
+            if (vm.Id == monitorId)
+            {
+                return vm;
+            }
+        }
+
+        return null;
+    }
+
+    /// <summary>
+    /// Setup settings file watcher
+    /// </summary>
+    private void SetupSettingsFileWatcher()
+    {
+        try
+        {
+            var settingsPath = _settingsUtils.GetSettingsFilePath("PowerDisplay");
+            var directory = Path.GetDirectoryName(settingsPath);
+            var fileName = Path.GetFileName(settingsPath);
+
+            if (!string.IsNullOrEmpty(directory))
+            {
+                // Ensure directory exists
+                if (!Directory.Exists(directory))
+                {
+                    Directory.CreateDirectory(directory);
+                }
+
+                _settingsWatcher = new FileSystemWatcher(directory, fileName)
+                {
+                    NotifyFilter = NotifyFilters.LastWrite | NotifyFilters.CreationTime,
+                    EnableRaisingEvents = true,
+                };
+
+                _settingsWatcher.Changed += OnSettingsFileChanged;
+                _settingsWatcher.Created += OnSettingsFileChanged;
+
+                Logger.LogInfo($"Settings file watcher setup for: {settingsPath}");
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Failed to setup settings file watcher: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Handle settings file changes - only monitors UI configuration changes from Settings UI
+    /// (monitor_state.json is managed separately and doesn't trigger this)
+    /// </summary>
+    private void OnSettingsFileChanged(object sender, FileSystemEventArgs e)
+    {
+        try
+        {
+            Logger.LogInfo($"Settings file changed by Settings UI: {e.FullPath}");
+
+            // Add small delay to ensure file write completion
+            Task.Delay(200).ContinueWith(_ =>
+            {
+                try
+                {
+                    // Read updated settings
+                    var settings = _settingsUtils.GetSettingsOrDefault<PowerDisplaySettings>("PowerDisplay");
+
+                    _dispatcherQueue.TryEnqueue(() =>
+                    {
+                        // Update feature visibility for each monitor (UI configuration only)
+                        foreach (var monitorVm in Monitors)
+                        {
+                            // Use HardwareId for lookup (unified identification)
+                            Logger.LogInfo($"[Settings Update] Looking for monitor settings with Hardware ID: '{monitorVm.HardwareId}'");
+
+                            var monitorSettings = settings.Properties.Monitors.FirstOrDefault(m =>
+                                m.HardwareId == monitorVm.HardwareId);
+
+                            if (monitorSettings != null)
+                            {
+                                Logger.LogInfo($"[Settings Update] Found monitor settings for Hardware ID '{monitorVm.HardwareId}': ColorTemp={monitorSettings.EnableColorTemperature}, Contrast={monitorSettings.EnableContrast}, Volume={monitorSettings.EnableVolume}");
+
+                                // Update visibility flags based on Settings UI toggles
+                                monitorVm.ShowColorTemperature = monitorSettings.EnableColorTemperature;
+                                monitorVm.ShowContrast = monitorSettings.EnableContrast;
+                                monitorVm.ShowVolume = monitorSettings.EnableVolume;
+                            }
+                            else
+                            {
+                                Logger.LogWarning($"[Settings Update] No monitor settings found for Hardware ID '{monitorVm.HardwareId}'");
+                                Logger.LogInfo($"[Settings Update] Available monitors in settings:");
+                                foreach (var availableMonitor in settings.Properties.Monitors)
+                                {
+                                    Logger.LogInfo($"  - Hardware: '{availableMonitor.HardwareId}', Name: '{availableMonitor.Name}'");
+                                }
+                            }
+                        }
+
+                        // Trigger UI refresh for configuration changes
+                        UIRefreshRequested?.Invoke(this, EventArgs.Empty);
+                    });
+
+                    Logger.LogInfo($"Settings UI configuration reloaded, monitor count: {settings.Properties.Monitors.Count}");
+                }
+                catch (Exception ex)
+                {
+                    Logger.LogError($"Failed to reload settings: {ex.Message}");
+                }
+            });
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Error handling settings file change: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Safe wrapper for initializing color temperature asynchronously
+    /// </summary>
+    private async Task InitializeColorTemperatureSafeAsync(string monitorId, MonitorViewModel vm)
+    {
+        try
+        {
+            await _monitorManager.InitializeColorTemperatureAsync(monitorId);
+
+            // Update UI on dispatcher thread - get the monitor from manager
+            var monitor = _monitorManager.GetMonitor(monitorId);
+            if (monitor != null)
+            {
+                _dispatcherQueue.TryEnqueue(() =>
+                {
+                    // Update color temperature without triggering hardware write
+                    vm.UpdatePropertySilently(nameof(vm.ColorTemperature), monitor.CurrentColorTemperature);
+                });
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogWarning($"Failed to initialize color temperature for {monitorId}: {ex.Message}");
+        }
+    }
+
+    // INotifyPropertyChanged
+    public event PropertyChangedEventHandler? PropertyChanged;
+
+    protected virtual void OnPropertyChanged([CallerMemberName] string? propertyName = null)
+    {
+        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+    }
+
+    /// <summary>
+    /// Reload monitor settings from configuration
+    /// </summary>
+    /// <param name="colorTempInitTasks">Optional tasks for color temperature initialization to wait for</param>
+    public async Task ReloadMonitorSettingsAsync(List<Task>? colorTempInitTasks = null)
+    {
+        // Prevent duplicate calls
+        if (IsLoading)
+        {
+            Logger.LogInfo("[Startup] ReloadMonitorSettingsAsync already in progress, skipping");
+            return;
+        }
+
+        try
+        {
+            // Set loading state to block UI interactions
+            IsLoading = true;
+            StatusText = "Loading settings...";
+
+            // Read current settings
+            var settings = _settingsUtils.GetSettingsOrDefault<PowerDisplaySettings>("PowerDisplay");
+
+            if (settings.Properties.RestoreSettingsOnStartup)
+            {
+                // Restore saved settings from configuration file
+                Logger.LogInfo("[Startup] RestoreSettingsOnStartup enabled - applying saved settings");
+
+                foreach (var monitorVm in Monitors)
+                {
+                    var hardwareId = monitorVm.HardwareId;
+                    Logger.LogInfo($"[Startup] Processing monitor: '{monitorVm.Name}', HardwareId: '{hardwareId}'");
+
+                    // Find and apply corresponding saved settings from state file using stable HardwareId
+                    var savedState = _stateManager.GetMonitorParameters(hardwareId);
+                    if (savedState.HasValue)
+                    {
+                        Logger.LogInfo($"[Startup] Restoring state for HardwareId '{hardwareId}': Brightness={savedState.Value.Brightness}, ColorTemp={savedState.Value.ColorTemperature}");
+
+                        // Validate and apply saved values (skip invalid values)
+                        // Use UpdatePropertySilently to avoid triggering hardware updates during initialization
+                        if (savedState.Value.Brightness >= monitorVm.MinBrightness && savedState.Value.Brightness <= monitorVm.MaxBrightness)
+                        {
+                            monitorVm.UpdatePropertySilently(nameof(monitorVm.Brightness), savedState.Value.Brightness);
+                        }
+                        else
+                        {
+                            Logger.LogWarning($"[Startup] Invalid brightness value {savedState.Value.Brightness} for HardwareId '{hardwareId}', skipping");
+                        }
+
+                        // Color temperature must be valid and within range
+                        if (savedState.Value.ColorTemperature > 0 &&
+                            savedState.Value.ColorTemperature >= monitorVm.MinColorTemperature &&
+                            savedState.Value.ColorTemperature <= monitorVm.MaxColorTemperature)
+                        {
+                            monitorVm.UpdatePropertySilently(nameof(monitorVm.ColorTemperature), savedState.Value.ColorTemperature);
+                        }
+                        else
+                        {
+                            Logger.LogWarning($"[Startup] Invalid color temperature value {savedState.Value.ColorTemperature} for HardwareId '{hardwareId}', skipping");
+                        }
+
+                        // Contrast validation - only apply if hardware supports it
+                        if (monitorVm.ShowContrast &&
+                            savedState.Value.Contrast >= monitorVm.MinContrast &&
+                            savedState.Value.Contrast <= monitorVm.MaxContrast)
+                        {
+                            monitorVm.UpdatePropertySilently(nameof(monitorVm.Contrast), savedState.Value.Contrast);
+                        }
+                        else if (!monitorVm.ShowContrast)
+                        {
+                            Logger.LogInfo($"[Startup] Contrast not supported on HardwareId '{hardwareId}', skipping");
+                        }
+
+                        // Volume validation - only apply if hardware supports it
+                        if (monitorVm.ShowVolume &&
+                            savedState.Value.Volume >= monitorVm.MinVolume &&
+                            savedState.Value.Volume <= monitorVm.MaxVolume)
+                        {
+                            monitorVm.UpdatePropertySilently(nameof(monitorVm.Volume), savedState.Value.Volume);
+                        }
+                        else if (!monitorVm.ShowVolume)
+                        {
+                            Logger.LogInfo($"[Startup] Volume not supported on HardwareId '{hardwareId}', skipping");
+                        }
+                    }
+                    else
+                    {
+                        Logger.LogInfo($"[Startup] No saved state for HardwareId '{hardwareId}' - keeping current hardware values");
+                    }
+
+                    // Apply feature visibility settings using HardwareId
+                    ApplyFeatureVisibility(monitorVm, settings);
+                }
+
+                StatusText = "Saved settings restored successfully";
+            }
+            else
+            {
+                // Save current hardware values to configuration file
+                Logger.LogInfo("[Startup] RestoreSettingsOnStartup disabled - saving current hardware values");
+
+                // Wait for color temperature initialization to complete (if any)
+                if (colorTempInitTasks != null && colorTempInitTasks.Count > 0)
+                {
+                    Logger.LogInfo("[Startup] Waiting for color temperature initialization to complete...");
+                    try
+                    {
+                        await Task.WhenAll(colorTempInitTasks);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogWarning($"[Startup] Some color temperature initializations failed: {ex.Message}");
+                    }
+                }
+
+                foreach (var monitorVm in Monitors)
+                {
+                    // Save current hardware values to settings
+                    SaveMonitorSettingDirect(monitorVm.HardwareId, "Brightness", monitorVm.Brightness);
+                    SaveMonitorSettingDirect(monitorVm.HardwareId, "ColorTemperature", monitorVm.ColorTemperature);
+                    SaveMonitorSettingDirect(monitorVm.HardwareId, "Contrast", monitorVm.Contrast);
+                    SaveMonitorSettingDirect(monitorVm.HardwareId, "Volume", monitorVm.Volume);
+
+                    Logger.LogInfo($"[Startup] Saved current values for Hardware ID '{monitorVm.HardwareId}': Brightness={monitorVm.Brightness}, ColorTemp={monitorVm.ColorTemperature}");
+
+                    // Apply feature visibility settings
+                    ApplyFeatureVisibility(monitorVm, settings);
+                }
+
+                // No need to flush - MonitorStateManager now saves directly!
+                StatusText = "Current monitor values saved to state file";
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Failed to reload/save settings: {ex.Message}");
+            StatusText = $"Failed to process settings: {ex.Message}";
+        }
+        finally
+        {
+            // Clear loading state to enable UI interactions
+            IsLoading = false;
+        }
+    }
+
+    /// <summary>
+    /// Apply feature visibility settings to a monitor ViewModel
+    /// </summary>
+    private void ApplyFeatureVisibility(MonitorViewModel monitorVm, PowerDisplaySettings settings)
+    {
+        var monitorSettings = settings.Properties.Monitors.FirstOrDefault(m =>
+            m.HardwareId == monitorVm.HardwareId);
+
+        if (monitorSettings != null)
+        {
+            Logger.LogInfo($"[Startup] Applying feature visibility for Hardware ID '{monitorVm.HardwareId}': ColorTemp={monitorSettings.EnableColorTemperature}, Contrast={monitorSettings.EnableContrast}, Volume={monitorSettings.EnableVolume}");
+
+            monitorVm.ShowColorTemperature = monitorSettings.EnableColorTemperature;
+            monitorVm.ShowContrast = monitorSettings.EnableContrast;
+            monitorVm.ShowVolume = monitorSettings.EnableVolume;
+        }
+        else
+        {
+            Logger.LogWarning($"[Startup] No feature settings found for Hardware ID '{monitorVm.HardwareId}' - using defaults");
+        }
+    }
+
+    /// <summary>
+    /// Thread-safe save method that can be called from background threads.
+    /// Does not access UI collections or update UI properties.
+    /// </summary>
+    public void SaveMonitorSettingDirect(string hardwareId, string property, int value)
+    {
+        try
+        {
+            // This is thread-safe - _stateManager has internal locking
+            // No UI thread operations, no ObservableCollection access
+            _stateManager.UpdateMonitorParameter(hardwareId, property, value);
+
+            Logger.LogTrace($"[State] Queued setting change for HardwareId '{hardwareId}': {property}={value}");
+        }
+        catch (Exception ex)
+        {
+            // Only log, don't update UI from background thread
+            Logger.LogError($"Failed to queue setting save for HardwareId '{hardwareId}': {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Reset a monitor to default values
+    /// </summary>
+    public void ResetMonitor(string monitorId)
+    {
+        try
+        {
+            var monitorVm = GetMonitorViewModel(monitorId);
+            if (monitorVm != null)
+            {
+                // Apply default values
+                monitorVm.Brightness = 30;
+                monitorVm.ColorTemperature = 6500;
+                monitorVm.Contrast = 50;
+                monitorVm.Volume = 50;
+
+                StatusText = $"Monitor {monitorVm.Name} reset to default values";
+            }
+        }
+        catch (Exception ex)
+        {
+            StatusText = $"Failed to reset monitor: {ex.Message}";
+        }
+    }
+
+    /// <summary>
+    /// Send monitor information to Settings UI via IPC (using standard Model)
+    /// </summary>
+    private void SendMonitorInfoToSettingsUI()
+    {
+        try
+        {
+            if (Monitors.Count == 0)
+            {
+                Logger.LogInfo("[IPC] No monitors to send to Settings UI");
+                return;
+            }
+
+            // Build monitor data list
+            var monitorsData = new List<MonitorInfoData>();
+
+            foreach (var vm in Monitors)
+            {
+                var monitorData = new MonitorInfoData
+                {
+                    Name = vm.Name,
+                    InternalName = vm.Id,
+                    HardwareId = vm.HardwareId,
+                    CommunicationMethod = GetCommunicationMethodString(vm.Type),
+                    MonitorType = vm.Type.ToString(),
+                    CurrentBrightness = vm.Brightness,
+                    ColorTemperature = vm.ColorTemperature,
+                };
+
+                monitorsData.Add(monitorData);
+            }
+
+            // Use standard IPC Response Model with JsonSerializer (source-generated for AOT)
+            var response = new PowerDisplayMonitorsIPCResponse(monitorsData);
+            string jsonMessage = System.Text.Json.JsonSerializer.Serialize(response, AppJsonContext.Default.PowerDisplayMonitorsIPCResponse);
+
+            // Send to Settings UI via IPC
+            App.SendIPCMessage(jsonMessage);
+
+            Logger.LogInfo($"[IPC] Sent {Monitors.Count} monitors to Settings UI");
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"[IPC] Failed to send monitor info: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Get communication method string based on monitor type
+    /// </summary>
+    private string GetCommunicationMethodString(MonitorType type)
+    {
+        return type switch
+        {
+            MonitorType.External => "DDC/CI",
+            MonitorType.Internal => "WMI",
+            _ => "Unknown",
+        };
+    }
+
+    // IDisposable
+    public void Dispose()
+    {
+        try
+        {
+            // Cancel all async operations first
+            _cancellationTokenSource?.Cancel();
+
+            // Stop file monitoring immediately
+            _settingsWatcher?.Dispose();
+            _settingsWatcher = null;
+
+            // No need to flush state - MonitorStateManager now saves directly on each update!
+            // State is already persisted, no pending changes to wait for.
+
+            // Quick cleanup of monitor view models
+            try
+            {
+                foreach (var vm in Monitors)
+                {
+                    vm?.Dispose();
+                }
+
+                Monitors.Clear();
+            }
+            catch
+            {
+                /* Ignore cleanup errors */
+            }
+
+            // Release monitor manager
+            try
+            {
+                _monitorManager?.Dispose();
+            }
+            catch
+            {
+                /* Ignore cleanup errors */
+            }
+
+            // Release state manager
+            try
+            {
+                _stateManager?.Dispose();
+            }
+            catch
+            {
+                /* Ignore cleanup errors */
+            }
+
+            // Finally release cancellation token
+            try
+            {
+                _cancellationTokenSource?.Dispose();
+            }
+            catch
+            {
+                /* Ignore cleanup errors */
+            }
+
+            GC.SuppressFinalize(this);
+        }
+        catch
+        {
+            // Ensure Dispose doesn't throw exceptions
+        }
+    }
+}

src/modules/powerdisplay/PowerDisplay/ViewModels/MonitorViewModel.cs

@@ -0,0 +1,459 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+using System.Threading.Tasks;
+using System.Windows.Input;
+using ManagedCommon;
+using Microsoft.UI.Xaml;
+using PowerDisplay.Commands;
+using PowerDisplay.Core;
+using PowerDisplay.Core.Models;
+using PowerDisplay.Helpers;
+using Monitor = PowerDisplay.Core.Models.Monitor;
+
+namespace PowerDisplay.ViewModels;
+
+/// <summary>
+/// ViewModel for individual monitor
+/// </summary>
+public partial class MonitorViewModel : INotifyPropertyChanged, IDisposable
+{
+    private readonly Monitor _monitor;
+    private readonly MonitorManager _monitorManager;
+    private readonly MainViewModel? _mainViewModel;
+
+    // Simple debouncers for each property (KISS principle - simpler than complex queue)
+    private readonly SimpleDebouncer _brightnessDebouncer = new(300);
+    private readonly SimpleDebouncer _colorTempDebouncer = new(300);
+    private readonly SimpleDebouncer _contrastDebouncer = new(300);
+    private readonly SimpleDebouncer _volumeDebouncer = new(300);
+
+    private int _brightness;
+    private int _colorTemperature;
+    private int _contrast;
+    private int _volume;
+    private bool _isAvailable;
+
+    // Visibility settings (controlled by Settings UI)
+    private bool _showColorTemperature;
+    private bool _showContrast;
+    private bool _showVolume;
+
+    /// <summary>
+    /// Updates a property value directly without triggering hardware updates.
+    /// Used during initialization to update UI from saved state.
+    /// </summary>
+    internal void UpdatePropertySilently(string propertyName, int value)
+    {
+        switch (propertyName)
+        {
+            case nameof(ColorTemperature):
+                _colorTemperature = value;
+                OnPropertyChanged(nameof(ColorTemperature));
+                OnPropertyChanged(nameof(ColorTemperaturePercent));
+                break;
+            case nameof(Brightness):
+                _brightness = value;
+                OnPropertyChanged(nameof(Brightness));
+                break;
+            case nameof(Contrast):
+                _contrast = value;
+                OnPropertyChanged(nameof(Contrast));
+                OnPropertyChanged(nameof(ContrastPercent));
+                break;
+            case nameof(Volume):
+                _volume = value;
+                OnPropertyChanged(nameof(Volume));
+                break;
+        }
+    }
+
+    // Conversion function for x:Bind (AOT-compatible alternative to converters)
+    public Visibility ConvertBoolToVisibility(bool value) => value ? Visibility.Visible : Visibility.Collapsed;
+
+    // Property to access IsInteractionEnabled from parent ViewModel
+    public bool IsInteractionEnabled => _mainViewModel?.IsInteractionEnabled ?? true;
+
+    public MonitorViewModel(Monitor monitor, MonitorManager monitorManager, MainViewModel mainViewModel)
+    {
+        _monitor = monitor;
+        _monitorManager = monitorManager;
+        _mainViewModel = mainViewModel;
+
+        // Subscribe to MainViewModel property changes to update IsInteractionEnabled
+        if (_mainViewModel != null)
+        {
+            _mainViewModel.PropertyChanged += OnMainViewModelPropertyChanged;
+        }
+
+        // Initialize Show properties based on hardware capabilities
+        _showColorTemperature = monitor.SupportsColorTemperature; // Only show for DDC/CI monitors that support it
+        _showContrast = monitor.SupportsContrast;
+        _showVolume = monitor.SupportsVolume;
+
+        // Try to get current color temperature via DDC/CI, use default if failed
+        try
+        {
+            // For DDC/CI monitors that support color temperature, use 6500K as default
+            // The actual temperature will be loaded asynchronously after construction
+            if (monitor.SupportsColorTemperature)
+            {
+                _colorTemperature = 6500; // Default neutral temperature for DDC monitors
+            }
+            else
+            {
+                _colorTemperature = 6500; // Default for unsupported monitors
+            }
+
+            monitor.CurrentColorTemperature = _colorTemperature;
+            Logger.LogDebug($"Initialized {monitor.Id} with default color temperature {_colorTemperature}K");
+        }
+        catch (Exception ex)
+        {
+            Logger.LogWarning($"Failed to initialize color temperature for {monitor.Id}: {ex.Message}");
+            _colorTemperature = 6500; // Default neutral temperature
+            monitor.CurrentColorTemperature = 6500;
+        }
+
+        // Initialize basic properties from monitor
+        _brightness = monitor.CurrentBrightness;
+        _contrast = monitor.CurrentContrast;
+        _volume = monitor.CurrentVolume;
+        _isAvailable = monitor.IsAvailable;
+    }
+
+    public string Id => _monitor.Id;
+
+    public string HardwareId => _monitor.HardwareId;
+
+    public string Name => _monitor.Name;
+
+    public string Manufacturer => _monitor.Manufacturer;
+
+    public MonitorType Type => _monitor.Type;
+
+    public string TypeDisplay => Type == MonitorType.Internal ? "Internal" : "External";
+
+    /// <summary>
+    /// Gets the icon glyph based on monitor type
+    /// </summary>
+    public string MonitorIconGlyph => Type == MonitorType.Internal ? "\uEA37" : "\uE7F4";
+
+    // Monitor property ranges
+    public int MinBrightness => _monitor.MinBrightness;
+
+    public int MaxBrightness => _monitor.MaxBrightness;
+
+    public int MinColorTemperature => _monitor.MinColorTemperature;
+
+    public int MaxColorTemperature => _monitor.MaxColorTemperature;
+
+    public int MinContrast => _monitor.MinContrast;
+
+    public int MaxContrast => _monitor.MaxContrast;
+
+    public int MinVolume => _monitor.MinVolume;
+
+    public int MaxVolume => _monitor.MaxVolume;
+
+    // Advanced control display logic
+    public bool HasAdvancedControls => ShowColorTemperature || ShowContrast || ShowVolume;
+
+    public bool ShowColorTemperature
+    {
+        get => _showColorTemperature;
+        set
+        {
+            if (_showColorTemperature != value)
+            {
+                _showColorTemperature = value;
+                OnPropertyChanged();
+                OnPropertyChanged(nameof(HasAdvancedControls));
+            }
+        }
+    }
+
+    public bool ShowContrast
+    {
+        get => _showContrast;
+        set
+        {
+            if (_showContrast != value)
+            {
+                _showContrast = value;
+                OnPropertyChanged();
+                OnPropertyChanged(nameof(HasAdvancedControls));
+            }
+        }
+    }
+
+    public bool ShowVolume
+    {
+        get => _showVolume;
+        set
+        {
+            if (_showVolume != value)
+            {
+                _showVolume = value;
+                OnPropertyChanged();
+                OnPropertyChanged(nameof(HasAdvancedControls));
+            }
+        }
+    }
+
+    public int Brightness
+    {
+        get => _brightness;
+        set
+        {
+            if (_brightness != value)
+            {
+                // Update UI state immediately - keep slider smooth
+                _brightness = value;
+                OnPropertyChanged(); // UI responds immediately
+
+                // Debounce hardware update - much simpler than complex queue!
+                var capturedValue = value; // Capture value for async closure
+                _brightnessDebouncer.Debounce(async () =>
+                {
+                    try
+                    {
+                        await _monitorManager.SetBrightnessAsync(Id, capturedValue);
+                        _mainViewModel?.SaveMonitorSettingDirect(_monitor.HardwareId, "Brightness", capturedValue);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError($"Failed to set brightness for {Id}: {ex.Message}");
+                    }
+                });
+            }
+        }
+    }
+
+    public int ColorTemperature
+    {
+        get => _colorTemperature;
+        set
+        {
+            if (_colorTemperature != value)
+            {
+                _colorTemperature = value;
+                OnPropertyChanged();
+
+                // Debounce hardware update - simple and clean!
+                var capturedValue = value;
+                _colorTempDebouncer.Debounce(async () =>
+                {
+                    try
+                    {
+                        var result = await _monitorManager.SetColorTemperatureAsync(Id, capturedValue);
+                        if (result.IsSuccess)
+                        {
+                            _monitor.CurrentColorTemperature = capturedValue;
+                            _mainViewModel?.SaveMonitorSettingDirect(_monitor.HardwareId, "ColorTemperature", capturedValue);
+                        }
+                        else
+                        {
+                            Logger.LogError($"[{Id}] Failed to set color temperature: {result.ErrorMessage}");
+                        }
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError($"Failed to set color temperature for {Id}: {ex.Message}");
+                    }
+                });
+            }
+        }
+    }
+
+    public int Contrast
+    {
+        get => _contrast;
+        set
+        {
+            if (_contrast != value)
+            {
+                _contrast = value;
+                OnPropertyChanged();
+
+                // Debounce hardware update
+                var capturedValue = value;
+                _contrastDebouncer.Debounce(async () =>
+                {
+                    try
+                    {
+                        await _monitorManager.SetContrastAsync(Id, capturedValue);
+                        _mainViewModel?.SaveMonitorSettingDirect(_monitor.HardwareId, "Contrast", capturedValue);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError($"Failed to set contrast for {Id}: {ex.Message}");
+                    }
+                });
+            }
+        }
+    }
+
+    public int Volume
+    {
+        get => _volume;
+        set
+        {
+            if (_volume != value)
+            {
+                _volume = value;
+                OnPropertyChanged();
+
+                // Debounce hardware update
+                var capturedValue = value;
+                _volumeDebouncer.Debounce(async () =>
+                {
+                    try
+                    {
+                        await _monitorManager.SetVolumeAsync(Id, capturedValue);
+                        _mainViewModel?.SaveMonitorSettingDirect(_monitor.HardwareId, "Volume", capturedValue);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.LogError($"Failed to set volume for {Id}: {ex.Message}");
+                    }
+                });
+            }
+        }
+    }
+
+    public bool IsAvailable
+    {
+        get => _isAvailable;
+        set
+        {
+            _isAvailable = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public ICommand SetBrightnessCommand => new RelayCommand<int?>((brightness) =>
+    {
+        if (brightness.HasValue)
+        {
+            Brightness = brightness.Value;
+        }
+    });
+
+    public ICommand SetColorTemperatureCommand => new RelayCommand<int?>((temperature) =>
+    {
+        if (temperature.HasValue && _monitor.SupportsColorTemperature)
+        {
+            Logger.LogDebug($"[{Id}] Color temperature command: {temperature.Value}K (DDC/CI)");
+            ColorTemperature = temperature.Value;
+        }
+        else if (temperature.HasValue && !_monitor.SupportsColorTemperature)
+        {
+            Logger.LogWarning($"[{Id}] Color temperature not supported on this monitor");
+        }
+    });
+
+    public ICommand SetContrastCommand => new RelayCommand<int?>((contrast) =>
+    {
+        if (contrast.HasValue)
+        {
+            Contrast = contrast.Value;
+        }
+    });
+
+    public ICommand SetVolumeCommand => new RelayCommand<int?>((volume) =>
+    {
+        if (volume.HasValue)
+        {
+            Volume = volume.Value;
+        }
+    });
+
+    // Percentage-based properties for uniform slider behavior
+    public int ColorTemperaturePercent
+    {
+        get => MapToPercent(_colorTemperature, MinColorTemperature, MaxColorTemperature);
+        set
+        {
+            var actualValue = MapFromPercent(value, MinColorTemperature, MaxColorTemperature);
+            ColorTemperature = actualValue;
+        }
+    }
+
+    public int ContrastPercent
+    {
+        get => MapToPercent(_contrast, MinContrast, MaxContrast);
+        set
+        {
+            var actualValue = MapFromPercent(value, MinContrast, MaxContrast);
+            Contrast = actualValue;
+        }
+    }
+
+    // Mapping functions for percentage conversion
+    private int MapToPercent(int value, int min, int max)
+    {
+        if (max <= min)
+        {
+            return 0;
+        }
+
+        return (int)Math.Round((value - min) * 100.0 / (max - min));
+    }
+
+    private int MapFromPercent(int percent, int min, int max)
+    {
+        if (max <= min)
+        {
+            return min;
+        }
+
+        percent = Math.Clamp(percent, 0, 100);
+        return min + (int)Math.Round(percent * (max - min) / 100.0);
+    }
+
+    public event PropertyChangedEventHandler? PropertyChanged;
+
+    protected virtual void OnPropertyChanged([CallerMemberName] string? propertyName = null)
+    {
+        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+
+        // Notify percentage properties when actual values change
+        if (propertyName == nameof(ColorTemperature))
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(ColorTemperaturePercent)));
+        }
+        else if (propertyName == nameof(Contrast))
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(ContrastPercent)));
+        }
+    }
+
+    private void OnMainViewModelPropertyChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (e.PropertyName == nameof(MainViewModel.IsInteractionEnabled))
+        {
+            OnPropertyChanged(nameof(IsInteractionEnabled));
+        }
+    }
+
+    public void Dispose()
+    {
+        // Unsubscribe from MainViewModel events
+        if (_mainViewModel != null)
+        {
+            _mainViewModel.PropertyChanged -= OnMainViewModelPropertyChanged;
+        }
+
+        // Dispose all debouncers
+        _brightnessDebouncer?.Dispose();
+        _colorTempDebouncer?.Dispose();
+        _contrastDebouncer?.Dispose();
+        _volumeDebouncer?.Dispose();
+        GC.SuppressFinalize(this);
+    }
+}

src/modules/powerdisplay/PowerDisplay/ViewModels/ViewModelState.cs

@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace PowerDisplay.ViewModels
+{
+    /// <summary>
+    /// Represents the current state of a ViewModel
+    /// </summary>
+    public enum ViewModelState
+    {
+        /// <summary>
+        /// Initial state - ViewModel is being initialized
+        /// </summary>
+        Initializing,
+
+        /// <summary>
+        /// Loading state - data is being reloaded or refreshed
+        /// </summary>
+        Loading,
+
+        /// <summary>
+        /// Ready state - ViewModel is ready for user interaction
+        /// </summary>
+        Ready,
+
+        /// <summary>
+        /// Error state - ViewModel encountered an error
+        /// </summary>
+        Error,
+    }
+}

src/modules/powerdisplay/PowerDisplay/app.manifest

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3">
+  <assemblyIdentity version="1.0.0.0" name="PowerDisplay.app"/>
+  
+  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v2">
+    <security>
+      <requestedPrivileges xmlns="urn:schemas-microsoft-com:asm.v3">
+        <requestedExecutionLevel level="asInvoker" uiAccess="false" />
+      </requestedPrivileges>
+    </security>
+  </trustInfo>
+
+  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+    <application>
+      <!-- Windows 10 -->
+      <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}" />
+      <!-- Windows 11 -->
+      <supportedOS Id="{1f676c76-80e1-4239-95bb-83d0f6d0da78}" />
+    </application>
+  </compatibility>
+
+  <application xmlns="urn:schemas-microsoft-com:asm.v3">
+    <windowsSettings>
+      <!-- The combination of below two tags have the following effect:
+           1) Per-Monitor for >= Windows 10 Anniversary Update
+           2) System < Windows 10 Anniversary Update
+      -->
+      <dpiAware xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">true/PM</dpiAware>
+      <dpiAwareness xmlns="http://schemas.microsoft.com/SMI/2016/WindowsSettings">PerMonitorV2, PerMonitor</dpiAwareness>
+    </windowsSettings>
+  </application>
+</assembly>

src/modules/powerdisplay/PowerDisplayModuleInterface/Constants.h

@@ -0,0 +1,7 @@
+#include <string>
+
+namespace PowerDisplayConstants
+{
+    // Name of the powertoy module.
+    inline const std::wstring ModuleKey = L"PowerDisplay";
+}

src/modules/powerdisplay/PowerDisplayModuleInterface/PowerDisplayModuleInterface.rc

@@ -0,0 +1,97 @@
+// Microsoft Visual C++ generated resource script.
+//
+#include <windows.h>
+#include "resource.h"
+#include "../../../common/version/version.h"
+
+#define APSTUDIO_READONLY_SYMBOLS
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 2 resource.
+//
+#include "winres.h"
+
+/////////////////////////////////////////////////////////////////////////////
+#undef APSTUDIO_READONLY_SYMBOLS
+
+1 VERSIONINFO
+FILEVERSION FILE_VERSION
+PRODUCTVERSION PRODUCT_VERSION
+FILEFLAGSMASK VS_FFI_FILEFLAGSMASK
+#ifdef _DEBUG
+FILEFLAGS VS_FF_DEBUG
+#else
+FILEFLAGS 0x0L
+#endif
+FILEOS VOS_NT_WINDOWS32
+FILETYPE VFT_DLL
+FILESUBTYPE VFT2_UNKNOWN
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904b0" // US English (0x0409), Unicode (0x04B0) charset
+        BEGIN
+            VALUE "CompanyName", COMPANY_NAME
+            VALUE "FileDescription", FILE_DESCRIPTION
+            VALUE "FileVersion", FILE_VERSION_STRING
+            VALUE "InternalName", INTERNAL_NAME
+            VALUE "LegalCopyright", COPYRIGHT_NOTE
+            VALUE "OriginalFilename", ORIGINAL_FILENAME
+            VALUE "ProductName", PRODUCT_NAME
+            VALUE "ProductVersion", PRODUCT_VERSION_STRING
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x409, 1200 // US English (0x0409), Unicode (1200) charset
+    END
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+// English (United States) resources
+
+#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+#pragma code_page(1252)
+
+#ifdef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// TEXTINCLUDE
+//
+
+1 TEXTINCLUDE 
+BEGIN
+    "resource.h\0"
+END
+
+2 TEXTINCLUDE 
+BEGIN
+    "#include ""winres.h""\r\n"
+    "\0"
+END
+
+3 TEXTINCLUDE 
+BEGIN
+    "\r\n"
+    "\0"
+END
+
+#endif    // APSTUDIO_INVOKED
+
+#endif    // English (United States) resources
+/////////////////////////////////////////////////////////////////////////////
+
+
+
+#ifndef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 3 resource.
+//
+
+
+/////////////////////////////////////////////////////////////////////////////
+#endif    // not APSTUDIO_INVOKED
+

src/modules/powerdisplay/PowerDisplayModuleInterface/PowerDisplayModuleInterface.vcxproj

@@ -0,0 +1,133 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props')" />
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|x64">
+      <Configuration>Debug</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|x64">
+      <Configuration>Release</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <VCProjectVersion>16.0</VCProjectVersion>
+    <ProjectGuid>{D1234567-8901-2345-6789-ABCDEF012345}</ProjectGuid>
+    <Keyword>Win32Proj</Keyword>
+    <RootNamespace>PowerDisplayModuleInterface</RootNamespace>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Condition="'$(Configuration)'=='Debug'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)'=='Release'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+  <ImportGroup Label="ExtensionSettings">
+  </ImportGroup>
+  <ImportGroup Label="Shared">
+  </ImportGroup>
+  <ImportGroup>
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup>
+    <OutDir>..\..\..\..\$(Platform)\$(Configuration)\modules\PowerDisplay\</OutDir>
+    <IntDir>$(Platform)\$(Configuration)\PowerDisplayModuleInterface\</IntDir>
+    <TargetName>PowerToys.PowerDisplayModuleInterface</TargetName>
+  </PropertyGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)'=='Debug'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>_DEBUG;POWERDISPLAYMODULEINTERFACE_EXPORTS;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <AdditionalIncludeDirectories>..\..\..\common\inc;..\..\..\common\Telemetry;..\..\;..\..\..\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableUAC>false</EnableUAC>
+      <AdditionalDependencies>Shlwapi.lib;$(CoreLibraryDependencies);%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)'=='Release'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>NDEBUG;POWERDISPLAYMODULEINTERFACE_EXPORTS;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <AdditionalIncludeDirectories>..\..\..\common\inc;..\..\..\common\Telemetry;..\..\;..\..\..\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableUAC>false</EnableUAC>
+      <AdditionalDependencies>Shlwapi.lib;$(CoreLibraryDependencies);%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup>
+    <ClInclude Include="Constants.h" />
+    <ClInclude Include="pch.h" />
+    <ClInclude Include="PowerDisplayProcessManager.h" />
+    <ClInclude Include="resource.h" />
+    <ClInclude Include="trace.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="dllmain.cpp" />
+    <ClCompile Include="pch.cpp">
+      <PrecompiledHeader Condition="'$(UsePrecompiledHeaders)' != 'false'">Create</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="PowerDisplayProcessManager.cpp" />
+    <ClCompile Include="trace.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\common\logger\logger.vcxproj">
+      <Project>{d9b8fc84-322a-4f9f-bbb9-20915c47ddfd}</Project>
+    </ProjectReference>
+    <ProjectReference Include="..\..\..\common\SettingsAPI\SettingsAPI.vcxproj">
+      <Project>{6955446d-23f7-4023-9bb3-8657f904af99}</Project>
+    </ProjectReference>
+  </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="PowerDisplayModuleInterface.rc" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <Import Project="..\..\..\..\deps\spdlog.props" />
+  <ImportGroup Label="ExtensionTargets">
+    <Import Project="..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets')" />
+    <Import Project="..\..\..\..\packages\Microsoft.Windows.ImplementationLibrary.1.0.231216.1\build\native\Microsoft.Windows.ImplementationLibrary.targets" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.ImplementationLibrary.1.0.231216.1\build\native\Microsoft.Windows.ImplementationLibrary.targets')" />
+  </ImportGroup>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props'))" />
+    <Error Condition="!Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets'))" />
+    <Error Condition="!Exists('..\..\..\..\packages\Microsoft.Windows.ImplementationLibrary.1.0.231216.1\build\native\Microsoft.Windows.ImplementationLibrary.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\..\packages\Microsoft.Windows.ImplementationLibrary.1.0.231216.1\build\native\Microsoft.Windows.ImplementationLibrary.targets'))" />
+  </Target>
+</Project>

src/modules/powerdisplay/PowerDisplayModuleInterface/PowerDisplayModuleInterface.vcxproj.filters

@@ -0,0 +1,53 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="Source Files">
+      <UniqueIdentifier>{4FC737F1-C7A5-4376-A066-2A32D752A2FF}</UniqueIdentifier>
+      <Extensions>cpp;c;cc;cxx;c++;cppm;ixx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
+    </Filter>
+    <Filter Include="Header Files">
+      <UniqueIdentifier>{93995380-89BD-4b04-88EB-625FBE52EBFB}</UniqueIdentifier>
+      <Extensions>h;hh;hpp;hxx;h++;hm;inl;inc;ipp;xsd</Extensions>
+    </Filter>
+    <Filter Include="Resource Files">
+      <UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
+      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="pch.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="Constants.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="Trace.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="resource.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="dllmain.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="pch.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="Trace.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="RegistryPreviewExt.rc">
+      <Filter>Resource Files</Filter>
+    </ResourceCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+  <ItemGroup>
+    <Natvis Include="$(MSBuildThisFileDirectory)..\..\natvis\wil.natvis" />
+  </ItemGroup>
+</Project>

src/modules/powerdisplay/PowerDisplayModuleInterface/PowerDisplayProcessManager.cpp

@@ -0,0 +1,274 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#include "pch.h"
+#include "PowerDisplayProcessManager.h"
+
+#include <common/logger/logger.h>
+#include <common/utils/winapi_error.h>
+#include <common/interop/shared_constants.h>
+#include <atlstr.h>
+#include <format>
+
+namespace
+{
+    /// <summary>
+    /// Generate a pipe name with UUID suffix
+    /// </summary>
+    std::optional<std::wstring> get_pipe_uuid()
+    {
+        UUID temp_uuid;
+        wchar_t* uuid_chars = nullptr;
+
+        if (UuidCreate(&temp_uuid) == RPC_S_UUID_NO_ADDRESS)
+        {
+            const auto val = get_last_error_message(GetLastError());
+            Logger::error(L"UuidCreate cannot create guid. {}", val.has_value() ? val.value() : L"");
+            return std::nullopt;
+        }
+        else if (UuidToString(&temp_uuid, reinterpret_cast<RPC_WSTR*>(&uuid_chars)) != RPC_S_OK)
+        {
+            const auto val = get_last_error_message(GetLastError());
+            Logger::error(L"UuidToString cannot convert to string. {}", val.has_value() ? val.value() : L"");
+            return std::nullopt;
+        }
+
+        const auto uuid_str = std::wstring(uuid_chars);
+        RpcStringFree(reinterpret_cast<RPC_WSTR*>(&uuid_chars));
+
+        return uuid_str;
+    }
+}
+
+PowerDisplayProcessManager::~PowerDisplayProcessManager()
+{
+    stop();
+}
+
+void PowerDisplayProcessManager::start()
+{
+    m_enabled = true;
+    submit_task([this]() { refresh(); });
+}
+
+void PowerDisplayProcessManager::stop()
+{
+    m_enabled = false;
+    submit_task([this]() { refresh(); });
+}
+
+void PowerDisplayProcessManager::send_message_to_powerdisplay(const std::wstring& message)
+{
+    submit_task([this, message]() {
+        if (m_write_pipe)
+        {
+            try
+            {
+                const auto formatted = std::format(L"{}\r\n", message);
+                const CString msg(formatted.c_str());
+                const DWORD bytes_to_write = static_cast<DWORD>(msg.GetLength() * sizeof(TCHAR));
+
+                DWORD bytes_written = 0;
+                if (FAILED(m_write_pipe->Write(msg.GetString(), bytes_to_write, &bytes_written)))
+                {
+                    Logger::error(L"Failed to write message to PowerDisplay pipe");
+                }
+                else
+                {
+                    Logger::trace(L"Sent message to PowerDisplay: {}", message);
+                }
+            }
+            catch (...)
+            {
+                Logger::error(L"Exception while sending message to PowerDisplay");
+            }
+        }
+        else
+        {
+            Logger::warn(L"Cannot send message to PowerDisplay: pipe not connected");
+        }
+    });
+}
+
+void PowerDisplayProcessManager::submit_task(std::function<void()> task)
+{
+    m_thread_executor.submit(OnThreadExecutor::task_t{ task });
+}
+
+bool PowerDisplayProcessManager::is_process_running() const
+{
+    return m_hProcess != nullptr && WaitForSingleObject(m_hProcess, 0) == WAIT_TIMEOUT;
+}
+
+void PowerDisplayProcessManager::terminate_process()
+{
+    // Close pipe
+    m_write_pipe.reset();
+
+    // Terminate process
+    if (m_hProcess != nullptr)
+    {
+        TerminateProcess(m_hProcess, 1);
+        CloseHandle(m_hProcess);
+        m_hProcess = nullptr;
+    }
+
+    Logger::trace(L"PowerDisplay process terminated");
+}
+
+HRESULT PowerDisplayProcessManager::start_process(const std::wstring& pipe_uuid)
+{
+    const unsigned long powertoys_pid = GetCurrentProcessId();
+
+    // Pass both runner PID and pipe UUID to PowerDisplay.exe
+    const auto executable_args = std::format(L"{} {}", std::to_wstring(powertoys_pid), pipe_uuid);
+
+    SHELLEXECUTEINFOW sei{ sizeof(sei) };
+    sei.fMask = SEE_MASK_NOCLOSEPROCESS | SEE_MASK_FLAG_NO_UI;
+    sei.lpFile = L"WinUI3Apps\\PowerToys.PowerDisplay.exe";
+    sei.nShow = SW_SHOWNORMAL;
+    sei.lpParameters = executable_args.data();
+
+    if (ShellExecuteExW(&sei))
+    {
+        Logger::trace(L"Successfully started PowerDisplay process with UUID: {}", pipe_uuid);
+        terminate_process(); // Clean up old process if any
+        m_hProcess = sei.hProcess;
+        return S_OK;
+    }
+    else
+    {
+        Logger::error(L"PowerDisplay process failed to start. {}", get_last_error_or_default(GetLastError()));
+        return E_FAIL;
+    }
+}
+
+HRESULT PowerDisplayProcessManager::start_command_pipe(const std::wstring& pipe_uuid)
+{
+    const constexpr DWORD BUFSIZE = 4096 * 4;
+
+    // Create pipe for writing to PowerDisplay (OUT)
+    m_pipe_name_out = std::format(L"\\\\.\\pipe\\powertoys_powerdisplay_{}_out", pipe_uuid);
+
+    HANDLE hWritePipe = CreateNamedPipe(
+        m_pipe_name_out.c_str(),
+        PIPE_ACCESS_OUTBOUND | FILE_FLAG_OVERLAPPED,
+        PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE | PIPE_WAIT,
+        1,       // max instances
+        BUFSIZE, // out buffer size
+        0,       // in buffer size (not used for outbound)
+        0,       // client timeout
+        NULL     // default security
+    );
+
+    if (hWritePipe == NULL || hWritePipe == INVALID_HANDLE_VALUE)
+    {
+        Logger::error(L"Error creating write pipe for PowerDisplay");
+        return E_FAIL;
+    }
+
+    // Create overlapped event for waiting for client to connect
+    OVERLAPPED write_overlapped = { 0 };
+    write_overlapped.hEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
+
+    if (!write_overlapped.hEvent)
+    {
+        Logger::error(L"Error creating overlapped event for PowerDisplay pipe");
+        CloseHandle(hWritePipe);
+        return E_FAIL;
+    }
+
+    // Connect write pipe
+    if (!ConnectNamedPipe(hWritePipe, &write_overlapped))
+    {
+        const auto lastError = GetLastError();
+        if (lastError != ERROR_IO_PENDING && lastError != ERROR_PIPE_CONNECTED)
+        {
+            Logger::error(L"Error connecting to write pipe");
+            CloseHandle(write_overlapped.hEvent);
+            CloseHandle(hWritePipe);
+            return E_FAIL;
+        }
+    }
+
+    // Wait for pipe to connect (with timeout)
+    const constexpr DWORD client_timeout_millis = 5000;
+    DWORD wait_result = WaitForSingleObject(write_overlapped.hEvent, client_timeout_millis);
+
+    if (wait_result == WAIT_OBJECT_0)
+    {
+        // Pipe connected successfully
+        m_write_pipe = std::make_unique<CAtlFile>(hWritePipe);
+        CloseHandle(write_overlapped.hEvent);
+
+        Logger::trace(L"PowerDisplay command pipe connected successfully");
+        return S_OK;
+    }
+    else
+    {
+        Logger::error(L"Timeout waiting for PowerDisplay to connect to command pipe");
+        CloseHandle(write_overlapped.hEvent);
+        CloseHandle(hWritePipe);
+        return E_FAIL;
+    }
+}
+
+void PowerDisplayProcessManager::refresh()
+{
+    if (m_enabled == is_process_running())
+    {
+        // Already in correct state
+        return;
+    }
+
+    if (m_enabled)
+    {
+        // Start PowerDisplay process
+        Logger::trace(L"Starting PowerDisplay process");
+
+        const auto pipe_uuid = get_pipe_uuid();
+        if (!pipe_uuid)
+        {
+            Logger::error(L"Failed to generate pipe UUID");
+            return;
+        }
+
+        if (start_command_pipe(pipe_uuid.value()) != S_OK)
+        {
+            Logger::error(L"Failed to initialize command pipe");
+            return;
+        }
+
+        if (start_process(pipe_uuid.value()) != S_OK)
+        {
+            Logger::error(L"Failed to start PowerDisplay process, cleaning up pipes");
+            terminate_process();
+        }
+    }
+    else
+    {
+        // Stop PowerDisplay process
+        Logger::trace(L"Stopping PowerDisplay process");
+
+        // Send terminate message
+        send_message_to_powerdisplay(L"{\"action\":\"terminate\"}");
+
+        // Wait for graceful exit
+        if (m_hProcess != nullptr)
+        {
+            WaitForSingleObject(m_hProcess, 2000);
+        }
+
+        if (is_process_running())
+        {
+            Logger::warn(L"PowerDisplay process failed to gracefully exit, terminating");
+        }
+        else
+        {
+            Logger::trace(L"PowerDisplay process successfully exited");
+        }
+
+        terminate_process();
+    }
+}

src/modules/powerdisplay/PowerDisplayModuleInterface/PowerDisplayProcessManager.h

@@ -0,0 +1,75 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#pragma once
+
+#include <functional>
+#include <memory>
+#include <atlfile.h>
+#include <common/utils/OnThreadExecutor.h>
+
+/// <summary>
+/// Manages PowerDisplay.exe process lifecycle and bidirectional IPC communication
+/// </summary>
+class PowerDisplayProcessManager
+{
+private:
+    HANDLE m_hProcess = nullptr;
+    std::unique_ptr<CAtlFile> m_write_pipe;  // Write to PowerDisplay (OUT)
+    OnThreadExecutor m_thread_executor;
+    bool m_enabled = false;
+
+    // Pipe name for this session
+    std::wstring m_pipe_name_out;
+
+public:
+    PowerDisplayProcessManager() = default;
+    ~PowerDisplayProcessManager();
+
+    /// <summary>
+    /// Start PowerDisplay.exe process
+    /// </summary>
+    void start();
+
+    /// <summary>
+    /// Stop PowerDisplay.exe process
+    /// </summary>
+    void stop();
+
+    /// <summary>
+    /// Send message to PowerDisplay.exe
+    /// </summary>
+    void send_message_to_powerdisplay(const std::wstring& message);
+
+private:
+    /// <summary>
+    /// Submit task to thread executor
+    /// </summary>
+    void submit_task(std::function<void()> task);
+
+    /// <summary>
+    /// Check if PowerDisplay.exe is running
+    /// </summary>
+    bool is_process_running() const;
+
+    /// <summary>
+    /// Terminate PowerDisplay.exe process
+    /// </summary>
+    void terminate_process();
+
+    /// <summary>
+    /// Start PowerDisplay.exe with command line arguments
+    /// </summary>
+    HRESULT start_process(const std::wstring& pipe_uuid);
+
+    /// <summary>
+    /// Create named pipe for sending commands to PowerDisplay
+    /// </summary>
+    HRESULT start_command_pipe(const std::wstring& pipe_uuid);
+
+    /// <summary>
+    /// Refresh - start or stop process based on m_enabled state
+    /// </summary>
+    void refresh();
+};

src/modules/powerdisplay/PowerDisplayModuleInterface/Trace.cpp

@@ -0,0 +1,32 @@
+#include "pch.h"
+#include "trace.h"
+
+#include <common/Telemetry/TraceBase.h>
+
+TRACELOGGING_DEFINE_PROVIDER(
+    g_hProvider,
+    "Microsoft.PowerToys",
+    // {38e8889b-9731-53f5-e901-e8a7c1753074}
+    (0x38e8889b, 0x9731, 0x53f5, 0xe9, 0x01, 0xe8, 0xa7, 0xc1, 0x75, 0x30, 0x74),
+    TraceLoggingOptionProjectTelemetry());
+
+// Log if the user has enabled or disabled the app
+void Trace::EnablePowerDisplay(_In_ bool enabled) noexcept
+{
+    TraceLoggingWriteWrapper(
+        g_hProvider,
+        "PowerDisplay_EnablePowerDisplay",
+        ProjectTelemetryPrivacyDataTag(ProjectTelemetryTag_ProductAndServicePerformance),
+        TraceLoggingKeyword(PROJECT_KEYWORD_MEASURE),
+        TraceLoggingBoolean(enabled, "Enabled"));
+}
+
+// Log that the user tried to activate the app
+void Trace::ActivatePowerDisplay() noexcept
+{
+    TraceLoggingWriteWrapper(
+        g_hProvider,
+        "PowerDisplay_Activate",
+        ProjectTelemetryPrivacyDataTag(ProjectTelemetryTag_ProductAndServicePerformance),
+        TraceLoggingKeyword(PROJECT_KEYWORD_MEASURE));
+}

src/modules/powerdisplay/PowerDisplayModuleInterface/Trace.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <common/Telemetry/TraceBase.h>
+
+class Trace : public telemetry::TraceBase
+{
+public:
+    // Log if the user has enabled or disabled the app
+    static void EnablePowerDisplay(const bool enabled) noexcept;
+
+    // Log that the user tried to activate the app
+    static void ActivatePowerDisplay() noexcept;
+};

src/modules/powerdisplay/PowerDisplayModuleInterface/dllmain.cpp

@@ -0,0 +1,245 @@
+// dllmain.cpp : Defines the entry point for the DLL Application.
+#include "pch.h"
+#include <interface/powertoy_module_interface.h>
+#include <common/SettingsAPI/settings_objects.h>
+#include "trace.h"
+#include <common/interop/shared_constants.h>
+#include <common/utils/string_utils.h>
+#include <common/utils/winapi_error.h>
+#include <common/utils/logger_helper.h>
+#include <common/utils/resources.h>
+
+#include "resource.h"
+#include "Constants.h"
+#include "PowerDisplayProcessManager.h"
+
+extern "C" IMAGE_DOS_HEADER __ImageBase;
+
+BOOL APIENTRY DllMain(HMODULE /*hModule*/, DWORD ul_reason_for_call, LPVOID /*lpReserved*/)
+{
+    switch (ul_reason_for_call)
+    {
+    case DLL_PROCESS_ATTACH:
+        Trace::RegisterProvider();
+        break;
+    case DLL_THREAD_ATTACH:
+    case DLL_THREAD_DETACH:
+        break;
+    case DLL_PROCESS_DETACH:
+        Trace::UnregisterProvider();
+        break;
+    }
+    return TRUE;
+}
+
+const static wchar_t* MODULE_NAME = L"PowerDisplay";
+const static wchar_t* MODULE_DESC = L"A utility to manage display brightness and color temperature across multiple monitors.";
+
+namespace
+{
+    const wchar_t JSON_KEY_PROPERTIES[] = L"properties";
+    const wchar_t JSON_KEY_ENABLED[] = L"enabled";
+    const wchar_t JSON_KEY_HOTKEY_ENABLED[] = L"hotkey_enabled";
+}
+
+class PowerDisplayModule : public PowertoyModuleIface
+{
+private:
+    bool m_enabled = false;
+    bool m_hotkey_enabled = false;
+
+    // Process manager for handling PowerDisplay.exe lifecycle and IPC
+    PowerDisplayProcessManager m_process_manager;
+
+    void parse_hotkey_settings(PowerToysSettings::PowerToyValues settings)
+    {
+        auto settingsObject = settings.get_raw_json();
+        if (settingsObject.GetView().Size())
+        {
+            try
+            {
+                if (settingsObject.HasKey(JSON_KEY_PROPERTIES))
+                {
+                    auto properties = settingsObject.GetNamedObject(JSON_KEY_PROPERTIES);
+                    m_hotkey_enabled = properties.GetNamedBoolean(JSON_KEY_HOTKEY_ENABLED, false);
+                }
+                else
+                {
+                    Logger::info("Properties object not found in settings, using defaults");
+                    m_hotkey_enabled = false;
+                }
+            }
+            catch (...)
+            {
+                Logger::info("Failed to parse hotkey settings, using defaults");
+                m_hotkey_enabled = false;
+            }
+        }
+        else
+        {
+            Logger::info("Power Display settings are empty");
+            m_hotkey_enabled = false;
+        }
+    }
+
+    void init_settings()
+    {
+        try
+        {
+            PowerToysSettings::PowerToyValues settings =
+                PowerToysSettings::PowerToyValues::load_from_settings_file(get_key());
+
+            parse_hotkey_settings(settings);
+        }
+        catch (std::exception&)
+        {
+            Logger::error("Invalid json when trying to load the Power Display settings json from file.");
+        }
+    }
+
+public:
+    PowerDisplayModule()
+    {
+        LoggerHelpers::init_logger(MODULE_NAME, L"ModuleInterface", "PowerDisplay");
+        Logger::info("Power Display object is constructing");
+
+        init_settings();
+
+        // Note: PowerDisplay.exe will send messages directly to runner via named pipes
+        // The runner's message_receiver_thread will handle routing to Settings UI
+        // No need to set a callback here - the process manager just manages lifecycle
+    }
+
+    ~PowerDisplayModule()
+    {
+        if (m_enabled)
+        {
+            m_process_manager.stop();
+        }
+        m_enabled = false;
+    }
+
+    virtual void destroy() override
+    {
+        Logger::trace("PowerDisplay::destroy()");
+        if (m_enabled)
+        {
+            m_process_manager.stop();
+        }
+        delete this;
+    }
+
+    virtual const wchar_t* get_name() override
+    {
+        return MODULE_NAME;
+    }
+
+    virtual const wchar_t* get_key() override
+    {
+        return MODULE_NAME;
+    }
+
+    virtual powertoys_gpo::gpo_rule_configured_t gpo_policy_enabled_configuration() override
+    {
+        return powertoys_gpo::gpo_rule_configured_not_configured;
+    }
+
+    virtual bool get_config(wchar_t* buffer, int* buffer_size) override
+    {
+        HINSTANCE hinstance = reinterpret_cast<HINSTANCE>(&__ImageBase);
+
+        PowerToysSettings::Settings settings(hinstance, get_name());
+        settings.set_description(MODULE_DESC);
+
+        return settings.serialize_to_buffer(buffer, buffer_size);
+    }
+
+    virtual void call_custom_action(const wchar_t* action) override
+    {
+        try
+        {
+            PowerToysSettings::CustomActionObject action_object =
+                PowerToysSettings::CustomActionObject::from_json_string(action);
+
+            if (action_object.get_name() == L"Launch")
+            {
+                Logger::trace(L"Launch action received, sending show_window command");
+                m_process_manager.send_message_to_powerdisplay(L"{\"action\":\"show_window\"}");
+                Trace::ActivatePowerDisplay();
+            }
+            else if (action_object.get_name() == L"RefreshMonitors")
+            {
+                Logger::trace(L"RefreshMonitors action received");
+                m_process_manager.send_message_to_powerdisplay(L"{\"action\":\"refresh_monitors\"}");
+            }
+        }
+        catch (std::exception&)
+        {
+            Logger::error(L"Failed to parse action. {}", action);
+        }
+    }
+
+    virtual void set_config(const wchar_t* config) override
+    {
+        try
+        {
+            PowerToysSettings::PowerToyValues values =
+                PowerToysSettings::PowerToyValues::from_json_string(config, get_key());
+
+            parse_hotkey_settings(values);
+            values.save_to_settings_file();
+
+            // Notify PowerDisplay.exe that settings have been updated
+            auto message = std::format(L"{{\"action\":\"settings_updated\",\"config\":{}}}", config);
+            m_process_manager.send_message_to_powerdisplay(message);
+        }
+        catch (std::exception&)
+        {
+            Logger::error(L"Invalid json when trying to parse Power Display settings json.");
+        }
+    }
+
+    virtual void enable() override
+    {
+        m_enabled = true;
+        Trace::EnablePowerDisplay(true);
+
+        Logger::trace(L"PowerDisplay enabled, starting process manager");
+        m_process_manager.start();
+    }
+
+    virtual void disable() override
+    {
+        if (m_enabled)
+        {
+            Logger::trace(L"Disabling Power Display...");
+            m_process_manager.stop();
+        }
+
+        m_enabled = false;
+        Trace::EnablePowerDisplay(false);
+    }
+
+    virtual bool is_enabled() override
+    {
+        return m_enabled;
+    }
+
+    virtual bool on_hotkey(size_t /*hotkeyId*/) override
+    {
+        if (m_enabled)
+        {
+            Logger::trace(L"Power Display hotkey pressed");
+            // Send toggle window command
+            m_process_manager.send_message_to_powerdisplay(L"{\"action\":\"toggle_window\"}");
+            return true;
+        }
+
+        return false;
+    }
+};
+
+extern "C" __declspec(dllexport) PowertoyModuleIface* __cdecl powertoy_create()
+{
+    return new PowerDisplayModule();
+}

src/modules/powerdisplay/PowerDisplayModuleInterface/packages.config

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.Windows.CppWinRT" version="2.0.240111.5" targetFramework="native" />
+  <package id="Microsoft.Windows.ImplementationLibrary" version="1.0.231216.1" targetFramework="native" />
+</packages>

src/modules/powerdisplay/PowerDisplayModuleInterface/pch.cpp

@@ -0,0 +1 @@
+#include "pch.h"

src/modules/powerdisplay/PowerDisplayModuleInterface/pch.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+//#include <winrt/Windows.Foundation.h>
+#include <strsafe.h>
+#include <hIdUsage.h>
+#include <shellapi.h>
+
+#include <thread>
+
+#include <winrt/Windows.Foundation.Collections.h>
+//#include <Shlwapi.h>
+#include <common/SettingsAPI/settings_helpers.h>
+#include <common/logger/logger.h>

src/modules/powerdisplay/PowerDisplayModuleInterface/resource.h

@@ -0,0 +1,13 @@
+//{{NO_DEPENDENCIES}}
+// Microsoft Visual C++ generated include file.
+// Used by PowerDisplayExt.rc
+
+//////////////////////////////
+// Non-localizable
+
+#define FILE_DESCRIPTION "PowerToys PowerDisplay Module"
+#define INTERNAL_NAME "PowerToys.PowerDisplay"
+#define ORIGINAL_FILENAME "PowerToys.PowerDisplay.dll"
+
+// Non-localizable
+//////////////////////////////

src/runner/main.cpp

@@ -178,6 +178,7 @@ int runner(bool isProcessElevated, bool openSettings, std::string settingsWindow
             L"PowerToys.CmdPalModuleInterface.dll",
             L"PowerToys.ZoomItModuleInterface.dll",
             L"PowerToys.LightSwitchModuleInterface.dll",
+            L"PowerToys.PowerDisplayExt.dll",
         };
 
         for (auto moduleSubdir : knownModules)

src/runner/settings_window.cpp

@@ -323,6 +323,48 @@ void dispatch_received_json(const std::wstring& json_to_parse)
                 Logger::error(L"Failed to process get all hotkey conflicts request");
             }
         }
+        else if (name == L"powerdisplay_response")
+        {
+            try
+            {
+                // Forward PowerDisplay response messages to Settings UI
+                // PowerDisplay sends monitor information via IPC
+                std::unique_lock lock{ ipc_mutex };
+                if (current_settings_ipc)
+                {
+                    current_settings_ipc->send(value.Stringify().c_str());
+                }
+            }
+            catch (...)
+            {
+                Logger::error(L"Failed to forward PowerDisplay response to Settings");
+            }
+        }
+        else if (name == L"powerdisplay_command")
+        {
+            try
+            {
+                // Forward command from Settings UI to PowerDisplay module
+                Logger::trace(L"Received command from Settings UI to PowerDisplay");
+
+                // Find PowerDisplay module and send the command
+                auto moduleIt = modules().find(L"PowerDisplay");
+                if (moduleIt != modules().end())
+                {
+                    // Use call_custom_action to send the command
+                    // The command should contain an action field
+                    moduleIt->second->call_custom_action(value.Stringify().c_str());
+                }
+                else
+                {
+                    Logger::warn(L"PowerDisplay module not found, cannot send command");
+                }
+            }
+            catch (...)
+            {
+                Logger::error(L"Failed to forward command to PowerDisplay");
+            }
+        }
     }
     return;
 }
@@ -809,6 +851,8 @@ std::string ESettingsWindowNames_to_string(ESettingsWindowNames value)
         return "CmdPal";
     case ESettingsWindowNames::ZoomIt:
         return "ZoomIt";
+    case ESettingsWindowNames::PowerDisplay:
+        return "PowerDisplay";
     default:
     {
         Logger::error(L"Can't convert ESettingsWindowNames value={} to string", static_cast<int>(value));
@@ -948,6 +992,10 @@ ESettingsWindowNames ESettingsWindowNames_from_string(std::string value)
     {
         return ESettingsWindowNames::ZoomIt;
     }
+    else if (value == "PowerDisplay")
+    {
+        return ESettingsWindowNames::PowerDisplay;
+    }
     else
     {
         Logger::error(L"Can't convert string value={} to ESettingsWindowNames", winrt::to_hstring(value));
@@ -956,3 +1004,29 @@ ESettingsWindowNames ESettingsWindowNames_from_string(std::string value)
 
     return ESettingsWindowNames::Dashboard;
 }
+
+// Global function for PowerDisplay module to send messages to Settings UI
+void send_powerdisplay_message_to_settings_ui(const wchar_t* message)
+{
+    try
+    {
+        Logger::trace(L"Sending PowerDisplay message to Settings UI");
+
+        std::unique_lock lock{ ipc_mutex };
+        if (current_settings_ipc)
+        {
+            // Wrap the message in powerdisplay_response format
+            json::JsonObject wrapper;
+            wrapper.SetNamedValue(L"powerdisplay_response", json::JsonValue::Parse(message));
+            current_settings_ipc->send(wrapper.Stringify().c_str());
+        }
+        else
+        {
+            Logger::warn(L"current_settings_ipc is null, cannot send to Settings UI");
+        }
+    }
+    catch (const std::exception&)
+    {
+        Logger::error(L"Exception while sending PowerDisplay message to Settings UI");
+    }
+}

src/runner/settings_window.h

@@ -36,6 +36,7 @@ enum class ESettingsWindowNames
     NewPlus,
     CmdPal,
     ZoomIt,
+    PowerDisplay,
 };
 
 std::string ESettingsWindowNames_to_string(ESettingsWindowNames value);
@@ -47,3 +48,6 @@ void close_settings_window();
 void open_oobe_window();
 void open_scoobe_window();
 void open_flyout();
+
+// PowerDisplay IPC support
+void send_powerdisplay_message_to_settings_ui(const wchar_t* message);

src/settings-ui/Settings.UI.Library/AdvancedPasteProperties.cs

@@ -58,6 +58,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public AdvancedPasteAdditionalActions AdditionalActions { get; init; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.AdvancedPasteProperties);
     }
 }

src/settings-ui/Settings.UI.Library/BasePTModuleSettings.cs

@@ -2,13 +2,33 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
 namespace Microsoft.PowerToys.Settings.UI.Library
 {
+    /// <summary>
+    /// Base class for all PowerToys module settings.
+    /// </summary>
+    /// <remarks>
+    /// <para><strong>IMPORTANT for Native AOT compatibility:</strong></para>
+    /// <para>When creating a new class that inherits from <see cref="BasePTModuleSettings"/>,
+    /// you MUST register it in <see cref="SettingsSerializationContext"/> by adding a
+    /// <c>[JsonSerializable(typeof(YourNewSettingsClass))]</c> attribute.</para>
+    /// <para>Failure to register the type will cause <see cref="ToJsonString"/> to throw
+    /// <see cref="InvalidOperationException"/> at runtime.</para>
+    /// <para>See <see cref="SettingsSerializationContext"/> for registration instructions.</para>
+    /// </remarks>
     public abstract class BasePTModuleSettings
     {
+        // Cached JsonSerializerOptions for Native AOT compatibility
+        private static readonly JsonSerializerOptions _jsonSerializerOptions = new JsonSerializerOptions
+        {
+            TypeInfoResolver = SettingsSerializationContext.Default,
+        };
+
         // Gets or sets name of the powertoy module.
         [JsonPropertyName("name")]
         public string Name { get; set; }
@@ -17,11 +37,33 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("version")]
         public string Version { get; set; }
 
-        // converts the current to a json string.
+        /// <summary>
+        /// Converts the current settings object to a JSON string.
+        /// </summary>
+        /// <returns>JSON string representation of this settings object.</returns>
+        /// <exception cref="InvalidOperationException">
+        /// Thrown when the runtime type is not registered in <see cref="SettingsSerializationContext"/>.
+        /// All derived types must be registered with <c>[JsonSerializable(typeof(YourType))]</c> attribute.
+        /// </exception>
+        /// <remarks>
+        /// This method uses Native AOT-compatible JSON serialization. The runtime type must be
+        /// registered in <see cref="SettingsSerializationContext"/> for serialization to work.
+        /// </remarks>
         public virtual string ToJsonString()
         {
             // By default JsonSerializer will only serialize the properties in the base class. This can be avoided by passing the object type (more details at https://stackoverflow.com/a/62498888)
-            return JsonSerializer.Serialize(this, GetType());
+            var runtimeType = GetType();
+
+            // For Native AOT compatibility, get JsonTypeInfo from the TypeInfoResolver
+            var typeInfo = _jsonSerializerOptions.TypeInfoResolver?.GetTypeInfo(runtimeType, _jsonSerializerOptions);
+
+            if (typeInfo == null)
+            {
+                throw new InvalidOperationException($"Type {runtimeType.FullName} is not registered in SettingsSerializationContext. Please add it to the [JsonSerializable] attributes.");
+            }
+
+            // Use AOT-friendly serialization
+            return JsonSerializer.Serialize(this, typeInfo);
         }
 
         public override int GetHashCode()

src/settings-ui/Settings.UI.Library/BoolProperty.cs

@@ -37,7 +37,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.BoolProperty);
         }
 
         public bool TryToCmdRepresentable(out string result)

src/settings-ui/Settings.UI.Library/BoolPropertyJsonConverter.cs

@@ -12,14 +12,14 @@ namespace Microsoft.PowerToys.Settings.UI.Library
     {
         public override bool Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
         {
-            var boolProperty = JsonSerializer.Deserialize<BoolProperty>(ref reader, options);
+            var boolProperty = JsonSerializer.Deserialize(ref reader, SettingsSerializationContext.Default.BoolProperty);
             return boolProperty.Value;
         }
 
         public override void Write(Utf8JsonWriter writer, bool value, JsonSerializerOptions options)
         {
             var boolProperty = new BoolProperty(value);
-            JsonSerializer.Serialize(writer, boolProperty, options);
+            JsonSerializer.Serialize(writer, boolProperty, SettingsSerializationContext.Default.BoolProperty);
         }
     }
 }

src/settings-ui/Settings.UI.Library/CmdPalProperties.cs

@@ -43,7 +43,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
                 if (doc.RootElement.TryGetProperty(nameof(Hotkey), out JsonElement hotkeyElement))
                 {
-                    Hotkey = JsonSerializer.Deserialize<HotkeySettings>(hotkeyElement.GetRawText());
+                    Hotkey = JsonSerializer.Deserialize(hotkeyElement.GetRawText(), SettingsSerializationContext.Default.HotkeySettings);
                 }
             }
             catch (Exception)

src/settings-ui/Settings.UI.Library/ColorPickerProperties.cs

@@ -87,6 +87,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public bool ShowColorName { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ColorPickerProperties);
     }
 }

src/settings-ui/Settings.UI.Library/ColorPickerPropertiesVersion1.cs

@@ -54,6 +54,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public bool ShowColorName { get; set; }
 
         public override string ToString()
-            => JsonSerializer.Serialize(this);
+            => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ColorPickerPropertiesVersion1);
     }
 }

src/settings-ui/Settings.UI.Library/DoubleProperty.cs

@@ -27,7 +27,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // Returns a JSON version of the class settings configuration class.
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.DoubleProperty);
         }
     }
 }

src/settings-ui/Settings.UI.Library/EnabledModules.cs

@@ -530,6 +530,23 @@ namespace Microsoft.PowerToys.Settings.UI.Library
             }
         }
 
+        private bool powerDisplay;
+
+        [JsonPropertyName("PowerDisplay")]
+        public bool PowerDisplay
+        {
+            get => powerDisplay;
+            set
+            {
+                if (powerDisplay != value)
+                {
+                    LogTelemetryEvent(value);
+                    powerDisplay = value;
+                    NotifyChange();
+                }
+            }
+        }
+
         private void NotifyChange()
         {
             notifyEnabledChangedAction?.Invoke();

src/settings-ui/Settings.UI.Library/FileLocksmithLocalProperties.cs

@@ -21,7 +21,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.FileLocksmithLocalProperties);
         }
 
         // This function is required to implement the ISettingsConfig interface and obtain the settings configurations.

src/settings-ui/Settings.UI.Library/FileLocksmithProperties.cs

@@ -17,6 +17,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("bool_show_extended_menu")]
         public BoolProperty ExtendedContextMenuOnly { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.FileLocksmithProperties);
     }
 }

src/settings-ui/Settings.UI.Library/GeneralSettings.cs

@@ -109,7 +109,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // converts the current to a json string.
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.GeneralSettings);
         }
 
         private static string DefaultPowertoysVersion()

src/settings-ui/Settings.UI.Library/GeneralSettingsCustomAction.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.GeneralSettingsCustomAction);
         }
     }
 }

src/settings-ui/Settings.UI.Library/Helpers/SunTimes.cs

@@ -12,13 +12,18 @@ namespace Microsoft.PowerToys.Settings.UI.Library.Helpers
 {
     public struct SunTimes
     {
-        public int SunriseHour;
+        public int SunriseHour { get; set; }
-        public int SunriseMinute;
-        public int SunsetHour;
-        public int SunsetMinute;
-        public string Text;
 
-        public bool HasSunrise;
+        public int SunriseMinute { get; set; }
-        public bool HasSunset;
+
+        public int SunsetHour { get; set; }
+
+        public int SunsetMinute { get; set; }
+
+        public string Text { get; set; }
+
+        public bool HasSunrise { get; set; }
+
+        public bool HasSunset { get; set; }
     }
 }

src/settings-ui/Settings.UI.Library/ImageResizerSettings.cs

@@ -37,8 +37,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToJsonString()
         {
-            var options = _serializerOptions;
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.ImageResizerSettings);
-            return JsonSerializer.Serialize(this, options);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/IntProperty.cs

@@ -42,7 +42,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         // Returns a JSON version of the class settings configuration class.
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.IntProperty);
         }
 
         public static implicit operator IntProperty(int v)

src/settings-ui/Settings.UI.Library/KeyboardManagerProfile.cs

@@ -34,7 +34,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.KeyboardManagerProfile);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/MeasureToolProperties.cs

@@ -46,6 +46,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public IntProperty DefaultMeasureStyle { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.MeasureToolProperties);
     }
 }

src/settings-ui/Settings.UI.Library/MonitorInfo.cs

@@ -0,0 +1,201 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Text.Json.Serialization;
+using Microsoft.PowerToys.Settings.UI.Library.Helpers;
+
+namespace Microsoft.PowerToys.Settings.UI.Library
+{
+    public class MonitorInfo : Observable
+    {
+        private string _name = string.Empty;
+        private string _internalName = string.Empty;
+        private string _hardwareId = string.Empty;
+        private string _communicationMethod = string.Empty;
+        private string _monitorType = string.Empty;
+        private int _currentBrightness;
+        private int _colorTemperature = 6500;
+        private bool _isHidden;
+        private bool _enableColorTemperature;
+        private bool _enableContrast;
+        private bool _enableVolume;
+
+        public MonitorInfo()
+        {
+        }
+
+        public MonitorInfo(string name, string internalName, string communicationMethod)
+        {
+            Name = name;
+            InternalName = internalName;
+            CommunicationMethod = communicationMethod;
+        }
+
+        public MonitorInfo(string name, string internalName, string hardwareId, string communicationMethod, string monitorType, int currentBrightness, int colorTemperature)
+        {
+            Name = name;
+            InternalName = internalName;
+            HardwareId = hardwareId;
+            CommunicationMethod = communicationMethod;
+            MonitorType = monitorType;
+            CurrentBrightness = currentBrightness;
+            ColorTemperature = colorTemperature;
+        }
+
+        [JsonPropertyName("name")]
+        public string Name
+        {
+            get => _name;
+            set
+            {
+                if (_name != value)
+                {
+                    _name = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("internalName")]
+        public string InternalName
+        {
+            get => _internalName;
+            set
+            {
+                if (_internalName != value)
+                {
+                    _internalName = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("communicationMethod")]
+        public string CommunicationMethod
+        {
+            get => _communicationMethod;
+            set
+            {
+                if (_communicationMethod != value)
+                {
+                    _communicationMethod = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("hardwareId")]
+        public string HardwareId
+        {
+            get => _hardwareId;
+            set
+            {
+                if (_hardwareId != value)
+                {
+                    _hardwareId = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("monitorType")]
+        public string MonitorType
+        {
+            get => _monitorType;
+            set
+            {
+                if (_monitorType != value)
+                {
+                    _monitorType = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("currentBrightness")]
+        public int CurrentBrightness
+        {
+            get => _currentBrightness;
+            set
+            {
+                if (_currentBrightness != value)
+                {
+                    _currentBrightness = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("colorTemperature")]
+        public int ColorTemperature
+        {
+            get => _colorTemperature;
+            set
+            {
+                if (_colorTemperature != value)
+                {
+                    _colorTemperature = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("isHidden")]
+        public bool IsHidden
+        {
+            get => _isHidden;
+            set
+            {
+                if (_isHidden != value)
+                {
+                    _isHidden = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("enableColorTemperature")]
+        public bool EnableColorTemperature
+        {
+            get => _enableColorTemperature;
+            set
+            {
+                if (_enableColorTemperature != value)
+                {
+                    System.Diagnostics.Debug.WriteLine($"[MonitorInfo] EnableColorTemperature changing from {_enableColorTemperature} to {value} for monitor {Name}");
+                    _enableColorTemperature = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("enableContrast")]
+        public bool EnableContrast
+        {
+            get => _enableContrast;
+            set
+            {
+                if (_enableContrast != value)
+                {
+                    _enableContrast = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+
+        [JsonPropertyName("enableVolume")]
+        public bool EnableVolume
+        {
+            get => _enableVolume;
+            set
+            {
+                if (_enableVolume != value)
+                {
+                    _enableVolume = value;
+                    OnPropertyChanged();
+                }
+            }
+        }
+    }
+}

src/settings-ui/Settings.UI.Library/MonitorInfoData.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Text.Json.Serialization;
+
+namespace Microsoft.PowerToys.Settings.UI.Library
+{
+    /// <summary>
+    /// Monitor information data for IPC
+    /// </summary>
+    public class MonitorInfoData
+    {
+        [JsonPropertyName("name")]
+        public string Name { get; set; } = string.Empty;
+
+        [JsonPropertyName("internalName")]
+        public string InternalName { get; set; } = string.Empty;
+
+        [JsonPropertyName("hardwareId")]
+        public string HardwareId { get; set; } = string.Empty;
+
+        [JsonPropertyName("communicationMethod")]
+        public string CommunicationMethod { get; set; } = string.Empty;
+
+        [JsonPropertyName("monitorType")]
+        public string MonitorType { get; set; } = string.Empty;
+
+        [JsonPropertyName("currentBrightness")]
+        public int CurrentBrightness { get; set; }
+
+        [JsonPropertyName("colorTemperature")]
+        public int ColorTemperature { get; set; }
+    }
+}

src/settings-ui/Settings.UI.Library/MouseWithoutBordersProperties.cs

@@ -15,8 +15,9 @@ namespace Microsoft.PowerToys.Settings.UI.Library
     public struct ConnectionRequest
 #pragma warning restore SA1649 // File name should match first type name
     {
-        public string PCName;
+        public string PCName { get; set; }
-        public string SecurityKey;
+
+        public string SecurityKey { get; set; }
     }
 
     public struct NewKeyGenerationRequest

src/settings-ui/Settings.UI.Library/NewPlusProperties.cs

@@ -33,6 +33,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("ReplaceVariables")]
         public BoolProperty ReplaceVariables { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.NewPlusProperties);
     }
 }

src/settings-ui/Settings.UI.Library/OutGoingGeneralSettings.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.OutGoingGeneralSettings);
         }
     }
 }

src/settings-ui/Settings.UI.Library/OutGoingLanguageSettings.cs

@@ -23,7 +23,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public override string ToString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, SettingsSerializationContext.Default.OutGoingLanguageSettings);
         }
     }
 }

src/settings-ui/Settings.UI.Library/PeekPreviewSettings.cs

@@ -34,7 +34,7 @@ namespace Settings.UI.Library
 
         public string ToJsonString()
         {
-            return JsonSerializer.Serialize(this);
+            return JsonSerializer.Serialize(this, Microsoft.PowerToys.Settings.UI.Library.SettingsSerializationContext.Default.PeekPreviewSettings);
         }
 
         public string GetModuleName()

src/settings-ui/Settings.UI.Library/PeekProperties.cs

@@ -32,6 +32,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public BoolProperty EnableSpaceToActivate { get; set; }
 
-        public override string ToString() => JsonSerializer.Serialize(this);
+        public override string ToString() => JsonSerializer.Serialize(this, SettingsSerializationContext.Default.PeekProperties);
     }
 }

src/settings-ui/Settings.UI.Library/PowerDisplayActionMessage.cs

@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Text.Json.Serialization;
+
+namespace Microsoft.PowerToys.Settings.UI.Library
+{
+    /// <summary>
+    /// Message for PowerDisplay module actions
+    /// </summary>
+    public class PowerDisplayActionMessage
+    {
+        [JsonPropertyName("action")]
+        public ActionData Action { get; set; }
+
+        public class ActionData
+        {
+            [JsonPropertyName("PowerDisplay")]
+            public PowerDisplayAction PowerDisplay { get; set; }
+        }
+
+        public class PowerDisplayAction
+        {
+            [JsonPropertyName("action_name")]
+            public string ActionName { get; set; }
+
+            [JsonPropertyName("value")]
+            public string Value { get; set; }
+        }
+    }
+}