Cmdpal: Peek command in indexer (#44581)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
Add a peek command, so we could quickly view the files found by indexer

I’m aware that wiring the Peek command directly into the indexer
extension is fairly PowerToys-specific.
I’m open to suggestions if we think this should instead be handled via a
more general extension / plugin mechanism; if a broader framework is
planned, I’m happy to wait and revisit this once that structure is in
place.

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## PR Checklist

- [ ] Closes: #43517
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issues) -->
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
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repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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## Detailed Description of the Pull Request / Additional comments

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src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Commands/PeekFileCommand.cs

@@ -0,0 +1,73 @@
+// 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;
+using Microsoft.CmdPal.Ext.Indexer.Properties;
+using Microsoft.CommandPalette.Extensions.Toolkit;
+
+namespace Microsoft.CmdPal.Ext.Indexer.Commands;
+
+/// <summary>
+/// Command to preview a file using PowerToys Peek.
+/// </summary>
+public sealed partial class PeekFileCommand : InvokableCommand
+{
+    private const string PeekExecutable = @"WinUI3Apps\PowerToys.Peek.UI.exe";
+
+    private static readonly Lazy<string> _peekPath = new(GetPeekExecutablePath);
+
+    private readonly string _fullPath;
+
+    public PeekFileCommand(string fullPath)
+    {
+        _fullPath = fullPath;
+        Name = Resources.Indexer_Command_Peek;
+        Icon = Icons.PeekIcon;
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether Peek is available on this system.
+    /// </summary>
+    public static bool IsPeekAvailable => !string.IsNullOrEmpty(_peekPath.Value);
+
+    public override CommandResult Invoke()
+    {
+        var peekExe = _peekPath.Value;
+        if (string.IsNullOrEmpty(peekExe))
+        {
+            return CommandResult.ShowToast(Resources.Indexer_Command_Peek_NotAvailable);
+        }
+
+        try
+        {
+            using var process = new Process();
+            process.StartInfo.FileName = peekExe;
+            process.StartInfo.Arguments = $"\"{_fullPath}\"";
+            process.StartInfo.UseShellExecute = false;
+            process.Start();
+        }
+        catch (Exception ex)
+        {
+            ExtensionHost.LogMessage($"Unable to launch Peek for {_fullPath}\n{ex}");
+            return CommandResult.ShowToast(Resources.Indexer_Command_Peek_Failed);
+        }
+
+        return CommandResult.Dismiss();
+    }
+
+    private static string GetPeekExecutablePath()
+    {
+        var installPath = PowerToysPathResolver.GetPowerToysInstallPath();
+        if (string.IsNullOrEmpty(installPath))
+        {
+            return string.Empty;
+        }
+
+        var peekPath = Path.Combine(installPath, PeekExecutable);
+        return File.Exists(peekPath) ? peekPath : string.Empty;
+    }
+}

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Data/IndexerListItem.cs

@@ -7,6 +7,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Microsoft.CmdPal.Core.Common.Commands;
+using Microsoft.CmdPal.Ext.Indexer.Commands;
 using Microsoft.CmdPal.Ext.Indexer.Helpers;
 using Microsoft.CmdPal.Ext.Indexer.Pages;
 using Microsoft.CmdPal.Ext.Indexer.Properties;
@@ -96,6 +97,13 @@ internal sealed partial class IndexerListItem : ListItem
         }
 
         commands.Add(new CommandContextItem(new OpenWithCommand(fullPath)));
+
+        // Add Peek command if available (only for files, not directories)
+        if (!isDir && PeekFileCommand.IsPeekAvailable)
+        {
+            commands.Add(new CommandContextItem(new PeekFileCommand(fullPath)) { RequestedShortcut = KeyChords.Peek });
+        }
+
         commands.Add(new CommandContextItem(new ShowFileInFolderCommand(fullPath) { Name = Resources.Indexer_Command_ShowInFolder }) { RequestedShortcut = KeyChords.OpenFileLocation });
         commands.Add(new CommandContextItem(new CopyPathCommand(fullPath) { Name = Resources.Indexer_Command_CopyPath }) { RequestedShortcut = KeyChords.CopyFilePath });
         commands.Add(new CommandContextItem(new OpenInConsoleCommand(fullPath)) { RequestedShortcut = KeyChords.OpenInConsole });

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Icons.cs

@@ -23,4 +23,6 @@ internal static class Icons
     internal static IconInfo FilesIcon { get; } = new("\uF571"); // PrintAllPages
 
     internal static IconInfo FilterIcon { get; } = new("\uE71C"); // Filter
+
+    internal static IconInfo PeekIcon { get; } = IconHelpers.FromRelativePath("Assets\\Peek.png");
 }

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/KeyChords.cs

@@ -4,6 +4,8 @@
 
 using Microsoft.CmdPal.Core.Common.Helpers;
 using Microsoft.CommandPalette.Extensions;
+using Microsoft.CommandPalette.Extensions.Toolkit;
+using Windows.System;
 
 namespace Microsoft.CmdPal.Ext.Indexer;
 
@@ -14,4 +16,6 @@ internal static class KeyChords
     internal static KeyChord CopyFilePath { get; } = WellKnownKeyChords.CopyFilePath;
 
     internal static KeyChord OpenInConsole { get; } = WellKnownKeyChords.OpenInConsole;
+
+    internal static KeyChord Peek { get; } = KeyChordHelpers.FromModifiers(ctrl: true, vkey: (int)VirtualKey.Space);
 }

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Microsoft.CmdPal.Ext.Indexer.csproj

@@ -42,6 +42,9 @@
     <Content Update="Assets\FileExplorer.svg">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Content Update="Assets\Peek.png">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
   </ItemGroup>
 
   <ItemGroup>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Properties/Resources.Designer.cs

@@ -132,6 +132,33 @@ namespace Microsoft.CmdPal.Ext.Indexer.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Peek preview.
+        /// </summary>
+        internal static string Indexer_Command_Peek {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Failed to launch Peek.
+        /// </summary>
+        internal static string Indexer_Command_Peek_Failed {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek_Failed", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to PowerToys Peek is not available.
+        /// </summary>
+        internal static string Indexer_Command_Peek_NotAvailable {
+            get {
+                return ResourceManager.GetString("Indexer_Command_Peek_NotAvailable", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Search all files.
         /// </summary>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Indexer/Properties/Resources.resx

@@ -202,4 +202,13 @@ You can try searching all files on this PC or adjust your indexing settings.</va
   <data name="Indexer_Filter_Files_Only" xml:space="preserve">
     <value>Files</value>
   </data>
+  <data name="Indexer_Command_Peek" xml:space="preserve">
+    <value>Peek preview</value>
+  </data>
+  <data name="Indexer_Command_Peek_NotAvailable" xml:space="preserve">
+    <value>PowerToys Peek is not available</value>
+  </data>
+  <data name="Indexer_Command_Peek_Failed" xml:space="preserve">
+    <value>Failed to launch Peek</value>
+  </data>
 </root>