[Run] Switch to WPF UI theme manager (#30520)

* Switch to WPF UI theme manager

* fix

* add theme manager

* fix

* fix

* update error icon

* moved image initialization

* cleanup

src/modules/launcher/PowerLauncher/Helper/ThemeExtensions.cs

@@ -0,0 +1,46 @@
+// 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.Linq;
+using ManagedCommon;
+using Microsoft.Win32;
+using Wpf.Ui.Appearance;
+
+namespace PowerLauncher.Helper
+{
+    public static class ThemeExtensions
+    {
+        public static Theme ToTheme(this ApplicationTheme applicationTheme)
+        {
+            return applicationTheme switch
+            {
+                ApplicationTheme.Dark => Theme.Dark,
+                ApplicationTheme.Light => Theme.Light,
+                ApplicationTheme.HighContrast => GetHighContrastBaseType(),
+                _ => Theme.Light,
+            };
+        }
+
+        private static Theme GetHighContrastBaseType()
+        {
+            string registryKey = @"HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Themes";
+            string theme = (string)Registry.GetValue(registryKey, "CurrentTheme", string.Empty);
+            theme = theme.Split('\\').Last().Split('.').First().ToString();
+
+            switch (theme)
+            {
+                case "hc1":
+                    return Theme.HighContrastOne;
+                case "hc2":
+                    return Theme.HighContrastTwo;
+                case "hcwhite":
+                    return Theme.HighContrastWhite;
+                case "hcblack":
+                    return Theme.HighContrastBlack;
+                default:
+                    return Theme.HighContrastOne;
+            }
+        }
+    }
+}

src/modules/launcher/PowerLauncher/Helper/ThemeManager.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;
+using ManagedCommon;
+using Wox.Infrastructure.Image;
+using Wox.Infrastructure.UserSettings;
+using Wpf.Ui.Appearance;
+
+namespace PowerLauncher.Helper
+{
+    public class ThemeManager : IDisposable
+    {
+        private readonly PowerToysRunSettings _settings;
+        private readonly MainWindow _mainWindow;
+        private Theme _currentTheme;
+        private bool _disposed;
+
+        public Theme CurrentTheme => _currentTheme;
+
+        public event Common.UI.ThemeChangedHandler ThemeChanged;
+
+        public ThemeManager(PowerToysRunSettings settings, MainWindow mainWindow)
+        {
+            _settings = settings;
+            _mainWindow = mainWindow;
+            _currentTheme = ApplicationThemeManager.GetAppTheme().ToTheme();
+            SetTheme(false);
+
+            ApplicationThemeManager.Changed += ApplicationThemeManager_Changed;
+        }
+
+        public void SetTheme(bool fromSettings)
+        {
+            if (_settings.Theme == Theme.Light)
+            {
+                _currentTheme = Theme.Light;
+                _mainWindow?.Dispatcher.Invoke(() => ApplicationThemeManager.Apply(ApplicationTheme.Light, _mainWindow.WindowBackdropType));
+            }
+            else if (_settings.Theme == Theme.Dark)
+            {
+                _currentTheme = Theme.Dark;
+                _mainWindow?.Dispatcher.Invoke(() => ApplicationThemeManager.Apply(ApplicationTheme.Dark, _mainWindow.WindowBackdropType));
+            }
+            else if (fromSettings)
+            {
+                _mainWindow?.Dispatcher.Invoke(ApplicationThemeManager.ApplySystemTheme);
+            }
+
+            ImageLoader.UpdateIconPath(_currentTheme);
+
+            // oldTheme isn't used
+            ThemeChanged?.Invoke(_currentTheme, _currentTheme);
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        private void ApplicationThemeManager_Changed(ApplicationTheme currentApplicationTheme, System.Windows.Media.Color systemAccent)
+        {
+            var newTheme = currentApplicationTheme.ToTheme();
+            if (_currentTheme == newTheme)
+            {
+                return;
+            }
+
+            _currentTheme = newTheme;
+            SetTheme(false);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposed)
+            {
+                return;
+            }
+
+            if (disposing)
+            {
+                ApplicationThemeManager.Changed -= ApplicationThemeManager_Changed;
+            }
+
+            _disposed = true;
+        }
+    }
+}