fix. 插件安装修复

LanMountainDesktop.Launcher/Infrastructure/Commands.cs

@@ -14,7 +14,7 @@ internal static class Commands
         {
             var source = context.GetOption("source") ?? string.Empty;
             var pluginsDir = context.GetOption("plugins-dir") ?? string.Empty;
-            result = installer.InstallPackage(source, pluginsDir);
+            result = installer.InstallPackage(source, pluginsDir, context.ExplicitAppRoot);
         }
         catch (Exception ex)
         {
@@ -91,12 +91,12 @@ internal static class Commands
             {
                 var source = context.GetOption("source") ?? throw new InvalidOperationException("Missing --source.");
                 var pluginsDir = context.GetOption("plugins-dir") ?? throw new InvalidOperationException("Missing --plugins-dir.");
-                return pluginInstaller.InstallPackage(source, pluginsDir);
+                return pluginInstaller.InstallPackage(source, pluginsDir, context.ExplicitAppRoot);
             }
             case "update":
             {
                 var pluginsDir = context.GetOption("plugins-dir") ?? throw new InvalidOperationException("Missing --plugins-dir.");
-                return pluginUpgrades.ApplyPendingUpgrades(pluginsDir);
+                return pluginUpgrades.ApplyPendingUpgrades(pluginsDir, context.ExplicitAppRoot);
             }
             default:
                 return new LauncherResult

LanMountainDesktop.Launcher/Infrastructure/DataLocationResolver.cs

@@ -193,8 +193,10 @@ internal sealed class DataLocationResolver
 
     public bool ApplyLocationChoice(DataLocationMode mode, string? customPath = null, bool migrateExistingData = false)
     {
-        var targetDataRoot = mode == DataLocationMode.Portable && !string.IsNullOrWhiteSpace(customPath)
+        var targetDataRoot = mode == DataLocationMode.Portable
-            ? Path.GetFullPath(customPath)
+            ? Path.GetFullPath(!string.IsNullOrWhiteSpace(customPath)
+                ? customPath
+                : DefaultPortableDataPath)
             : _defaultSystemDataPath;
 
         var config = new DataLocationConfig

LanMountainDesktop.Launcher/Plugins/PluginInstallerService.cs

@@ -22,7 +22,7 @@ internal sealed class PluginInstallerService
         TimeSpan.FromMilliseconds(500)
     ];
 
-    public LauncherResult InstallPackage(string sourcePath, string pluginsDirectory)
+    public LauncherResult InstallPackage(string sourcePath, string pluginsDirectory, string? appRoot = null)
     {
         var fullSourcePath = Path.GetFullPath(sourcePath);
         var fullPluginsDirectory = Path.GetFullPath(pluginsDirectory);
@@ -32,7 +32,7 @@ internal sealed class PluginInstallerService
             throw new FileNotFoundException($"Plugin package '{fullSourcePath}' was not found.", fullSourcePath);
         }
 
-        if (TryBuildElevationRequiredResult(fullPluginsDirectory) is { } elevationRequiredResult)
+        if (TryBuildElevationRequiredResult(fullPluginsDirectory, appRoot) is { } elevationRequiredResult)
         {
             return elevationRequiredResult;
         }
@@ -58,7 +58,7 @@ internal sealed class PluginInstallerService
         };
     }
 
-    private static LauncherResult? TryBuildElevationRequiredResult(string pluginsDirectory)
+    private static LauncherResult? TryBuildElevationRequiredResult(string pluginsDirectory, string? appRoot)
     {
         if (!OperatingSystem.IsWindows())
         {
@@ -68,8 +68,10 @@ internal sealed class PluginInstallerService
         string? allowedRoot = null;
         try
         {
-            var appRoot = Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolvedAppRoot = !string.IsNullOrWhiteSpace(appRoot)
-            var resolver = new DataLocationResolver(appRoot);
+                ? Path.GetFullPath(appRoot)
+                : Commands.ResolveAppRoot(CommandContext.FromArgs([]));
+            var resolver = new DataLocationResolver(resolvedAppRoot);
             allowedRoot = EnsureTrailingSeparator(resolver.ResolveDataRoot());
         }
         catch

LanMountainDesktop.Launcher/Plugins/PluginUpgradeQueueService.cs

@@ -14,7 +14,7 @@ internal sealed class PluginUpgradeQueueService
         _installerService = installerService;
     }
 
-    public LauncherResult ApplyPendingUpgrades(string pluginsDirectory)
+    public LauncherResult ApplyPendingUpgrades(string pluginsDirectory, string? appRoot = null)
     {
         var pendingPath = Path.Combine(pluginsDirectory, PendingUpgradesFileName);
         if (!File.Exists(pendingPath))
@@ -43,7 +43,7 @@ internal sealed class PluginUpgradeQueueService
 
             try
             {
-                _installerService.InstallPackage(item.SourcePackagePath, pluginsDirectory);
+                _installerService.InstallPackage(item.SourcePackagePath, pluginsDirectory, appRoot);
                 succeeded.Add(item);
             }
             catch

LanMountainDesktop.Tests/DataLocationResolverTests.cs

@@ -0,0 +1,35 @@
+using LanMountainDesktop.Launcher.Models;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class DataLocationResolverTests : IDisposable
+{
+    private readonly string _appRoot = Path.Combine(
+        Path.GetTempPath(),
+        "LanMountainDesktop.Tests",
+        nameof(DataLocationResolverTests),
+        Guid.NewGuid().ToString("N"));
+
+    [Fact]
+    public void ApplyLocationChoice_PortableWithoutCustomPath_UsesAppRootDesktopDirectory()
+    {
+        Directory.CreateDirectory(_appRoot);
+        var resolver = new DataLocationResolver(_appRoot);
+
+        var applied = resolver.ApplyLocationChoice(DataLocationMode.Portable);
+
+        Assert.True(applied);
+        Assert.Equal(
+            Path.Combine(Path.GetFullPath(_appRoot), "Desktop"),
+            resolver.ResolveDataRoot());
+    }
+
+    public void Dispose()
+    {
+        if (Directory.Exists(_appRoot))
+        {
+            Directory.Delete(_appRoot, recursive: true);
+        }
+    }
+}

LanMountainDesktop.Tests/PluginInstallerServiceTests.cs

@@ -1,5 +1,6 @@
 using LanMountainDesktop.Launcher.Plugins;
 using System.IO.Compression;
+using System.Text.Json;
 using Xunit;
 
 namespace LanMountainDesktop.Tests;
@@ -34,10 +35,10 @@ public sealed class PluginInstallerServiceTests : IDisposable
         Directory.CreateDirectory(_tempRoot);
         CreatePluginPackage(packagePath, "plugin.json", "plugin.install.sample", "Sample Plugin");
 
-        var pluginsDirectory = CreateUserScopedPluginsDirectory();
+        var pluginsDirectory = CreateConfiguredPortablePluginsDirectory(out var appRoot);
         var service = new PluginInstallerService();
 
-        var result = service.InstallPackage(packagePath, pluginsDirectory);
+        var result = service.InstallPackage(packagePath, pluginsDirectory, appRoot);
 
         Assert.True(result.Success);
         Assert.Equal("ok", result.Code);
@@ -49,6 +50,42 @@ public sealed class PluginInstallerServiceTests : IDisposable
         Assert.Empty(Directory.EnumerateFiles(pluginsDirectory, "*.incoming", SearchOption.AllDirectories));
     }
 
+    [Fact]
+    public void InstallPackage_AllowsConfiguredPortableDataRootOutsideUserScope()
+    {
+        if (!OperatingSystem.IsWindows())
+        {
+            return;
+        }
+
+        Directory.CreateDirectory(_tempRoot);
+        var appRoot = Path.Combine(_tempRoot, "PackageRoot");
+        var portableDataRoot = Path.Combine(appRoot, "Desktop");
+        var launcherDataRoot = Path.Combine(appRoot, ".Launcher");
+        Directory.CreateDirectory(launcherDataRoot);
+        File.WriteAllText(
+            Path.Combine(launcherDataRoot, "data-location.config.json"),
+            JsonSerializer.Serialize(new
+            {
+                DataLocationMode = "Portable",
+                SystemDataPath = Path.Combine(_tempRoot, "System"),
+                PortableDataPath = portableDataRoot
+            }));
+
+        var packagePath = Path.Combine(_tempRoot, "portable.laapp");
+        CreatePluginPackage(packagePath, "plugin.json", "plugin.portable.sample", "Portable Plugin");
+
+        var pluginsDirectory = Path.Combine(portableDataRoot, "Extensions", "Plugins");
+        var service = new PluginInstallerService();
+
+        var result = service.InstallPackage(packagePath, pluginsDirectory, appRoot);
+
+        Assert.True(result.Success);
+        Assert.Equal("ok", result.Code);
+        Assert.True(File.Exists(result.InstalledPackagePath));
+        Assert.StartsWith(Path.GetFullPath(portableDataRoot), Path.GetFullPath(result.InstalledPackagePath!), StringComparison.OrdinalIgnoreCase);
+    }
+
     [Fact]
     public void InstallPackage_ReplacesExistingPackageWithSamePluginId()
     {
@@ -58,11 +95,11 @@ public sealed class PluginInstallerServiceTests : IDisposable
         CreatePluginPackage(firstPackagePath, "plugin.json", "plugin.replace.sample", "Sample Plugin v1");
         CreatePluginPackage(secondPackagePath, "plugin.json", "plugin.replace.sample", "Sample Plugin v2");
 
-        var pluginsDirectory = CreateUserScopedPluginsDirectory();
+        var pluginsDirectory = CreateConfiguredPortablePluginsDirectory(out var appRoot);
         var service = new PluginInstallerService();
 
-        var first = service.InstallPackage(firstPackagePath, pluginsDirectory);
+        var first = service.InstallPackage(firstPackagePath, pluginsDirectory, appRoot);
-        var second = service.InstallPackage(secondPackagePath, pluginsDirectory);
+        var second = service.InstallPackage(secondPackagePath, pluginsDirectory, appRoot);
 
         Assert.True(first.Success);
         Assert.True(second.Success);
@@ -77,10 +114,10 @@ public sealed class PluginInstallerServiceTests : IDisposable
         Directory.CreateDirectory(_tempRoot);
         CreatePluginPackage(packagePath, "manifest.json", "plugin.legacy.sample", "Legacy Plugin");
 
-        var pluginsDirectory = CreateUserScopedPluginsDirectory();
+        var pluginsDirectory = CreateConfiguredPortablePluginsDirectory(out var appRoot);
         var service = new PluginInstallerService();
 
-        var result = service.InstallPackage(packagePath, pluginsDirectory);
+        var result = service.InstallPackage(packagePath, pluginsDirectory, appRoot);
 
         Assert.True(result.Success);
         Assert.Equal("plugin.legacy.sample", result.ManifestId);
@@ -103,18 +140,24 @@ public sealed class PluginInstallerServiceTests : IDisposable
               """);
     }
 
-    private static string CreateUserScopedPluginsDirectory()
+    private string CreateConfiguredPortablePluginsDirectory(out string appRoot)
     {
-        var root = Path.Combine(
+        appRoot = Path.Combine(_tempRoot, "ConfiguredPackageRoot", Guid.NewGuid().ToString("N"));
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+        var portableDataRoot = Path.Combine(appRoot, "Desktop");
-            "LanMountainDesktop",
+        var launcherDataRoot = Path.Combine(appRoot, ".Launcher");
-            "Tests",
+        Directory.CreateDirectory(launcherDataRoot);
-            nameof(PluginInstallerServiceTests),
+        File.WriteAllText(
-            Guid.NewGuid().ToString("N"),
+            Path.Combine(launcherDataRoot, "data-location.config.json"),
-            "Extensions",
+            JsonSerializer.Serialize(new
-            "Plugins");
+            {
-        Directory.CreateDirectory(root);
+                DataLocationMode = "Portable",
-        return root;
+                SystemDataPath = Path.Combine(_tempRoot, "System"),
+                PortableDataPath = portableDataRoot
+            }));
+
+        var pluginsDirectory = Path.Combine(portableDataRoot, "Extensions", "Plugins");
+        Directory.CreateDirectory(pluginsDirectory);
+        return pluginsDirectory;
     }
 
     public void Dispose()

LanMountainDesktop.Tests/PluginRuntimeDataPathTests.cs

@@ -0,0 +1,40 @@
+using LanMountainDesktop.Services;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class PluginRuntimeDataPathTests : IDisposable
+{
+    private readonly string _dataRoot = Path.Combine(
+        Path.GetTempPath(),
+        "LanMountainDesktop.Tests",
+        nameof(PluginRuntimeDataPathTests),
+        Guid.NewGuid().ToString("N"));
+
+    [Fact]
+    public void PluginRuntime_UsesHostDataRootForPluginsAndMarketData()
+    {
+        AppDataPathProvider.Initialize(["--data-root", _dataRoot]);
+
+        using var runtime = new PluginRuntimeService();
+
+        Assert.Equal(
+            Path.Combine(Path.GetFullPath(_dataRoot), "Extensions", "Plugins"),
+            runtime.PluginsDirectory);
+    }
+
+    public void Dispose()
+    {
+        AppDataPathProvider.ResetForTests();
+        try
+        {
+            if (Directory.Exists(_dataRoot))
+            {
+                Directory.Delete(_dataRoot, recursive: true);
+            }
+        }
+        catch
+        {
+        }
+    }
+}

LanMountainDesktop/Services/AppDataPathProvider.cs

@@ -50,6 +50,11 @@ public static class AppDataPathProvider
         return Path.Combine(GetDataRoot(), "Wallpapers");
     }
 
+    internal static void ResetForTests()
+    {
+        _overriddenDataRoot = null;
+    }
+
     private static string? ResolveDataRootFromArgs(string[] args)
     {
         const string prefix = "--data-root=";

LanMountainDesktop/Services/ElevatedPluginInstallService.cs

@@ -0,0 +1,237 @@
+using System;
+using System.Diagnostics;
+using System.IO;
+using System.Text.Json;
+using System.Threading;
+using System.Threading.Tasks;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+
+namespace LanMountainDesktop.Services;
+
+internal sealed record ElevatedPluginInstallResult(
+    bool Success,
+    string? Code,
+    string? Message,
+    string? ErrorMessage,
+    string? InstalledPackagePath,
+    string? ManifestId,
+    string? ManifestName);
+
+internal sealed class ElevatedPluginInstallService
+{
+    public async Task<ElevatedPluginInstallResult> InstallAsync(
+        string sourcePackagePath,
+        string pluginsDirectory,
+        CancellationToken cancellationToken)
+    {
+        ArgumentException.ThrowIfNullOrWhiteSpace(sourcePackagePath);
+        ArgumentException.ThrowIfNullOrWhiteSpace(pluginsDirectory);
+
+        if (!OperatingSystem.IsWindows())
+        {
+            return new ElevatedPluginInstallResult(
+                false,
+                "elevation_unsupported",
+                "Elevated plugin installation is only supported on Windows.",
+                "Elevated plugin installation is only supported on Windows.",
+                null,
+                null,
+                null);
+        }
+
+        var launcherPath = ResolveLauncherExecutablePath();
+        if (string.IsNullOrWhiteSpace(launcherPath) || !File.Exists(launcherPath))
+        {
+            return new ElevatedPluginInstallResult(
+                false,
+                "launcher_not_found",
+                "Launcher executable was not found for elevated plugin installation.",
+                $"Launcher executable was not found. ResolvedPath='{launcherPath ?? string.Empty}'.",
+                null,
+                null,
+                null);
+        }
+
+        var resultPath = Path.Combine(
+            Path.GetTempPath(),
+            $"LanMountainDesktop.PluginInstall.{Guid.NewGuid():N}.json");
+
+        try
+        {
+            var startInfo = new ProcessStartInfo
+            {
+                FileName = launcherPath,
+                UseShellExecute = true,
+                Verb = "runas",
+                WorkingDirectory = Path.GetDirectoryName(launcherPath) ?? AppContext.BaseDirectory
+            };
+            startInfo.ArgumentList.Add("plugin");
+            startInfo.ArgumentList.Add("install");
+            startInfo.ArgumentList.Add("--source");
+            startInfo.ArgumentList.Add(Path.GetFullPath(sourcePackagePath));
+            startInfo.ArgumentList.Add("--plugins-dir");
+            startInfo.ArgumentList.Add(Path.GetFullPath(pluginsDirectory));
+            startInfo.ArgumentList.Add("--result");
+            startInfo.ArgumentList.Add(resultPath);
+
+            var packageRoot = LauncherRuntimeMetadata.GetPackageRoot();
+            if (!string.IsNullOrWhiteSpace(packageRoot))
+            {
+                startInfo.ArgumentList.Add("--app-root");
+                startInfo.ArgumentList.Add(Path.GetFullPath(packageRoot));
+            }
+
+            var process = Process.Start(startInfo);
+            if (process is null)
+            {
+                return new ElevatedPluginInstallResult(
+                    false,
+                    "launch_failed",
+                    "Elevated plugin installer did not start.",
+                    "Elevated plugin installer did not start.",
+                    null,
+                    null,
+                    null);
+            }
+
+            await process.WaitForExitAsync(cancellationToken).ConfigureAwait(false);
+            if (File.Exists(resultPath))
+            {
+                return ReadResult(resultPath);
+            }
+
+            return new ElevatedPluginInstallResult(
+                process.ExitCode == 0,
+                process.ExitCode == 0 ? "ok" : "installer_failed",
+                process.ExitCode == 0 ? "Plugin installed." : $"Elevated installer exited with code {process.ExitCode}.",
+                process.ExitCode == 0 ? null : $"Elevated installer exited with code {process.ExitCode}.",
+                null,
+                null,
+                null);
+        }
+        catch (OperationCanceledException)
+        {
+            throw;
+        }
+        catch (System.ComponentModel.Win32Exception ex) when (ex.NativeErrorCode == 1223)
+        {
+            return new ElevatedPluginInstallResult(
+                false,
+                "elevation_cancelled",
+                "Plugin installation was cancelled before elevation was approved.",
+                ex.Message,
+                null,
+                null,
+                null);
+        }
+        catch (Exception ex)
+        {
+            return new ElevatedPluginInstallResult(
+                false,
+                "elevation_failed",
+                "Elevated plugin installation failed.",
+                ex.Message,
+                null,
+                null,
+                null);
+        }
+        finally
+        {
+            TryDelete(resultPath);
+        }
+    }
+
+    private static ElevatedPluginInstallResult ReadResult(string resultPath)
+    {
+        try
+        {
+            using var document = JsonDocument.Parse(File.ReadAllText(resultPath));
+            var root = document.RootElement;
+            return new ElevatedPluginInstallResult(
+                GetBoolean(root, "Success"),
+                GetString(root, "Code"),
+                GetString(root, "Message"),
+                GetString(root, "ErrorMessage"),
+                GetString(root, "InstalledPackagePath"),
+                GetString(root, "ManifestId"),
+                GetString(root, "ManifestName"));
+        }
+        catch (Exception ex)
+        {
+            return new ElevatedPluginInstallResult(
+                false,
+                "invalid_result",
+                "Elevated plugin installer returned an invalid result.",
+                ex.Message,
+                null,
+                null,
+                null);
+        }
+    }
+
+    private static string? ResolveLauncherExecutablePath()
+    {
+        var candidates = new[]
+        {
+            LauncherRuntimeMetadata.GetPackageRoot(),
+            AppContext.BaseDirectory,
+            Path.GetFullPath(Path.Combine(AppContext.BaseDirectory, ".."))
+        };
+
+        foreach (var root in candidates.Where(candidate => !string.IsNullOrWhiteSpace(candidate)))
+        {
+            var path = Path.Combine(root!, OperatingSystem.IsWindows()
+                ? "LanMountainDesktop.Launcher.exe"
+                : "LanMountainDesktop.Launcher");
+            if (File.Exists(path))
+            {
+                return path;
+            }
+        }
+
+        return null;
+    }
+
+    private static bool GetBoolean(JsonElement element, string propertyName)
+    {
+        return TryGetProperty(element, propertyName, out var property) &&
+               property.ValueKind == JsonValueKind.True;
+    }
+
+    private static string? GetString(JsonElement element, string propertyName)
+    {
+        return TryGetProperty(element, propertyName, out var property) &&
+               property.ValueKind == JsonValueKind.String
+            ? property.GetString()
+            : null;
+    }
+
+    private static bool TryGetProperty(JsonElement element, string propertyName, out JsonElement property)
+    {
+        foreach (var candidate in element.EnumerateObject())
+        {
+            if (string.Equals(candidate.Name, propertyName, StringComparison.OrdinalIgnoreCase))
+            {
+                property = candidate.Value;
+                return true;
+            }
+        }
+
+        property = default;
+        return false;
+    }
+
+    private static void TryDelete(string path)
+    {
+        try
+        {
+            if (File.Exists(path))
+            {
+                File.Delete(path);
+            }
+        }
+        catch
+        {
+        }
+    }
+}

LanMountainDesktop/Services/HostApplicationLifecycleService.cs

@@ -1,9 +1,7 @@
 using System;
 using System.Diagnostics;
-using System.IO;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
-using Avalonia.Threading;
 using LanMountainDesktop.PluginSdk;
 using LanMountainDesktop.Shared.Contracts.Launcher;
 
@@ -11,8 +9,6 @@ namespace LanMountainDesktop.Services;
 
 public sealed class HostApplicationLifecycleService : IHostApplicationLifecycle
 {
-    private const string UpgradeHelperExecutableName = "LanMountainDesktop.PluginUpgradeHelper.exe";
-
     public bool TryExit(HostApplicationLifecycleRequest? request = null)
     {
         App? app = null;
@@ -53,11 +49,6 @@ public sealed class HostApplicationLifecycleService : IHostApplicationLifecycle
                 return false;
             }
 
-            if (HasPendingPluginUpgrades())
-            {
-                return TryRestartWithUpgradeHelper(request);
-            }
-
             return TryRestartDirectly(request);
         }
         catch (Exception ex)
@@ -68,61 +59,6 @@ public sealed class HostApplicationLifecycleService : IHostApplicationLifecycle
         }
     }
 
-    private static bool HasPendingPluginUpgrades()
-    {
-        try
-        {
-            var pluginsDirectory = Path.Combine(
-                Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-                "LanMountainDesktop",
-                "Extensions",
-                "Plugins");
-            var pendingUpgradesPath = Path.Combine(pluginsDirectory, ".pending-plugin-upgrades.json");
-            return File.Exists(pendingUpgradesPath);
-        }
-        catch
-        {
-            return false;
-        }
-    }
-
-    private bool TryRestartWithUpgradeHelper(HostApplicationLifecycleRequest? request)
-    {
-        AppLogger.Info("HostLifecycle", "Detected pending plugin upgrades. Using upgrade helper for restart.");
-
-        var helperPath = ResolveUpgradeHelperPath();
-        if (!File.Exists(helperPath))
-        {
-            AppLogger.Warn("HostLifecycle", $"Upgrade helper not found at '{helperPath}'. Falling back to direct restart.");
-            return TryRestartDirectly(request);
-        }
-
-        var pluginsDirectory = Path.Combine(
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop",
-            "Extensions",
-            "Plugins");
-
-        var app = Application.Current as App;
-        var restartPresentationMode = app?.GetCurrentRestartPresentationMode() ?? RestartPresentationMode.Foreground;
-        var startInfo = AppRestartService.CreateRestartStartInfo(restartPresentationMode: restartPresentationMode);
-        var launchCommand = startInfo?.FileName ?? Process.GetCurrentProcess().MainModule?.FileName ?? AppContext.BaseDirectory;
-        var launchArgs = startInfo?.Arguments ?? "";
-
-        var helperStartInfo = new ProcessStartInfo
-        {
-            FileName = helperPath,
-            Arguments = $"--plugins-dir \"{pluginsDirectory}\" --parent-pid {Environment.ProcessId} --launch \"{launchCommand}\" --launch-args \"{launchArgs}\" --working-dir \"{AppContext.BaseDirectory}\"",
-            UseShellExecute = true,
-            WorkingDirectory = AppContext.BaseDirectory
-        };
-
-        AppLogger.Info("HostLifecycle", $"Starting upgrade helper: {helperStartInfo.FileName} {helperStartInfo.Arguments}");
-
-        Process.Start(helperStartInfo);
-        return app?.TrySubmitShutdown(HostShutdownMode.Restart, request) == true;
-    }
-
     private bool TryRestartDirectly(HostApplicationLifecycleRequest? request)
     {
         var app = Application.Current as App;
@@ -149,8 +85,4 @@ public sealed class HostApplicationLifecycleService : IHostApplicationLifecycle
         return app?.TrySubmitShutdown(HostShutdownMode.Restart, shutdownRequest) == true;
     }
 
-    private static string ResolveUpgradeHelperPath()
-    {
-        return Path.Combine(AppContext.BaseDirectory, "PluginUpgradeHelper", UpgradeHelperExecutableName);
-    }
 }

LanMountainDesktop/Services/PluginInstallTargetAccess.cs

@@ -0,0 +1,28 @@
+using System;
+using System.IO;
+
+namespace LanMountainDesktop.Services;
+
+internal static class PluginInstallTargetAccess
+{
+    public static bool CanWriteDirectory(string directory)
+    {
+        if (string.IsNullOrWhiteSpace(directory))
+        {
+            return false;
+        }
+
+        try
+        {
+            Directory.CreateDirectory(directory);
+            var probePath = Path.Combine(directory, $".write-test-{Guid.NewGuid():N}.tmp");
+            File.WriteAllText(probePath, string.Empty);
+            File.Delete(probePath);
+            return true;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+}

LanMountainDesktop/plugins/PluginMarketEmbeddedView.cs

@@ -67,10 +67,7 @@ internal sealed class PluginMarketEmbeddedView : UserControl, IDisposable
     public PluginMarketEmbeddedView(PluginRuntimeService runtime)
     {
         _runtime = runtime;
-        var dataDirectory = Path.Combine(
+        var dataDirectory = AppDataPathProvider.GetPluginMarketDirectory();
-            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
-            "LanMountainDesktop",
-            "AirAppMarket");
         _indexService = new AirAppMarketIndexService(new AirAppMarketCacheService(dataDirectory));
         _installService = new AirAppMarketInstallService(runtime, dataDirectory);
         _readmeService = new AirAppMarketReadmeService();

LanMountainDesktop/plugins/PluginMarketInstallService.cs

@@ -19,13 +19,14 @@ internal sealed class AirAppMarketInstallService : IDisposable
     private readonly ResumableDownloadService _downloadService;
     private readonly AirAppMarketReleaseResolverService _releaseResolverService;
     private readonly PendingPluginUpgradeService _pendingUpgradeService;
+    private readonly ElevatedPluginInstallService _elevatedInstallService = new();
     private readonly string _downloadsDirectory;
     private readonly Version? _hostVersion;
 
     public AirAppMarketInstallService(PluginRuntimeService runtime, string dataDirectory)
     {
         _runtime = runtime;
-        _downloadsDirectory = Path.Combine(dataDirectory, "downloads");
+        _downloadsDirectory = ResolveDownloadsDirectory(dataDirectory);
         _httpClient = new HttpClient
         {
             Timeout = TimeSpan.FromMinutes(2)
@@ -77,9 +78,10 @@ internal sealed class AirAppMarketInstallService : IDisposable
         bool isUpgrade,
         CancellationToken cancellationToken)
     {
+        var canWritePluginsDirectory = PluginInstallTargetAccess.CanWriteDirectory(_runtime.PluginsDirectory);
         AppLogger.Info(
             "PluginMarket",
-            $"Detected {(isUpgrade ? "upgrade" : "new install")} scenario. Downloading package for deferred install. PluginId='{plugin.Id}'.");
+            $"Detected {(isUpgrade ? "upgrade" : "new install")} scenario. Downloading package for {(canWritePluginsDirectory ? "deferred" : "elevated")} install. PluginId='{plugin.Id}'; PluginsDirectory='{_runtime.PluginsDirectory}'; CanWritePluginsDirectory={canWritePluginsDirectory}.");
 
         var sourceErrors = new List<string>();
         foreach (var source in sources)
@@ -98,6 +100,25 @@ internal sealed class AirAppMarketInstallService : IDisposable
             try
             {
                 var manifest = ReadManifestFromPackage(downloadResult.PackagePath);
+                if (!canWritePluginsDirectory)
+                {
+                    var elevatedResult = await _elevatedInstallService.InstallAsync(
+                        downloadResult.PackagePath,
+                        _runtime.PluginsDirectory,
+                        cancellationToken).ConfigureAwait(false);
+                    if (!elevatedResult.Success)
+                    {
+                        sourceErrors.Add($"{source.SourceKind}: {elevatedResult.ErrorMessage ?? elevatedResult.Message ?? elevatedResult.Code ?? "Elevated install failed."}");
+                        continue;
+                    }
+
+                    AppLogger.Info(
+                        "PluginMarket",
+                        $"Plugin package installed through elevated installer. PluginId='{manifest.Id}'; Version='{manifest.Version ?? plugin.Version}'; PackagePath='{downloadResult.PackagePath}'; IsUpgrade={isUpgrade}.");
+
+                    return new AirAppMarketInstallResult(true, manifest, null, RestartRequired: true);
+                }
+
                 _pendingUpgradeService.AddPendingInstallOrUpgrade(
                     manifest.Id,
                     downloadResult.PackagePath,
@@ -276,6 +297,21 @@ internal sealed class AirAppMarketInstallService : IDisposable
         }
     }
 
+    private static string ResolveDownloadsDirectory(string dataDirectory)
+    {
+        var preferred = Path.Combine(dataDirectory, "downloads");
+        if (PluginInstallTargetAccess.CanWriteDirectory(preferred))
+        {
+            return preferred;
+        }
+
+        var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+        var fallbackRoot = string.IsNullOrWhiteSpace(localAppData)
+            ? Path.GetTempPath()
+            : Path.Combine(localAppData, "LanMountainDesktop");
+        return Path.Combine(fallbackRoot, "PluginMarket", "downloads");
+    }
+
     private async Task<DownloadPackageResult> DownloadPackageAsync(
         AirAppMarketPluginEntry plugin,
         AirAppMarketPluginPackageSourceEntry source,

LanMountainDesktop/plugins/PluginRuntimeService.cs

@@ -46,9 +46,10 @@ public sealed class PluginRuntimeService : IDisposable
         ISettingsFacadeService? settingsFacade = null,
         PublicIpcHostService? publicIpcHostService = null)
     {
-        PluginsDirectory = Path.Combine(GetUserDataRootDirectory(), "Extensions", "Plugins");
+        var dataRoot = AppDataPathProvider.GetDataRoot();
+        PluginsDirectory = Path.Combine(dataRoot, "Extensions", "Plugins");
         _sharedContractManager = new PluginSharedContractManager(
-            Path.Combine(GetUserDataRootDirectory(), "PluginMarket"));
+            AppDataPathProvider.GetPluginMarketDirectory());
         _packageManager = new PluginRuntimePackageManager(this);
         _settingsFacade = settingsFacade ?? new SettingsFacadeService();
         _publicIpcHostService = publicIpcHostService;
@@ -388,9 +389,15 @@ public sealed class PluginRuntimeService : IDisposable
         AppLogger.Info(
             "PluginRuntime",
             $"Installing package. PluginId='{manifest.Id}'; Source='{fullPackagePath}'; PluginsDirectory='{PluginsDirectory}'.");
-        var replacedExisting = RemoveExistingPluginPackages(manifest.Id, fullPackagePath);
 
         var destinationPath = Path.Combine(PluginsDirectory, BuildInstalledPackageFileName(manifest.Id));
+        if (!PluginInstallTargetAccess.CanWriteDirectory(PluginsDirectory))
+        {
+            return InstallPluginPackageWithElevation(fullPackagePath, manifest, destinationPath);
+        }
+
+        var replacedExisting = RemoveExistingPluginPackages(manifest.Id, fullPackagePath);
+
         if (!string.Equals(fullPackagePath, Path.GetFullPath(destinationPath), StringComparison.OrdinalIgnoreCase))
         {
             FileOperationRetryHelper.CopyWithRetry(fullPackagePath, destinationPath, overwrite: true, "PluginRuntime");
@@ -405,6 +412,41 @@ public sealed class PluginRuntimeService : IDisposable
         return new PluginPackageInstallResult(manifest, replacedExisting, RestartRequired: true);
     }
 
+    private PluginPackageInstallResult InstallPluginPackageWithElevation(
+        string fullPackagePath,
+        PluginManifest manifest,
+        string destinationPath)
+    {
+        if (!OperatingSystem.IsWindows())
+        {
+            throw new UnauthorizedAccessException(
+                $"Plugin directory '{PluginsDirectory}' is not writable by the current process.");
+        }
+
+        var elevatedResult = new ElevatedPluginInstallService()
+            .InstallAsync(fullPackagePath, PluginsDirectory, CancellationToken.None)
+            .GetAwaiter()
+            .GetResult();
+        if (!elevatedResult.Success)
+        {
+            throw new UnauthorizedAccessException(
+                elevatedResult.ErrorMessage ??
+                elevatedResult.Message ??
+                $"Elevated plugin install failed with code '{elevatedResult.Code ?? "unknown"}'.");
+        }
+
+        var installedPath = !string.IsNullOrWhiteSpace(elevatedResult.InstalledPackagePath)
+            ? elevatedResult.InstalledPackagePath
+            : destinationPath;
+        UpdateCatalogAfterPackageInstall(manifest, installedPath);
+        PendingRestartStateService.SetPending(PendingRestartStateService.PluginCatalogReason, true);
+        AppLogger.Info(
+            "PluginRuntime",
+            $"Package staged through elevated installer. PluginId='{manifest.Id}'; Destination='{installedPath}'.");
+
+        return new PluginPackageInstallResult(manifest, ReplacedExisting: false, RestartRequired: true);
+    }
+
     private PluginManifest RegisterInstalledPluginPackageCore(string packagePath)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(packagePath);
@@ -694,17 +736,6 @@ public sealed class PluginRuntimeService : IDisposable
             : path + Path.DirectorySeparatorChar;
     }
 
-    private static string GetUserDataRootDirectory()
-    {
-        var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-        if (string.IsNullOrWhiteSpace(localAppData))
-        {
-            return Path.Combine(AppContext.BaseDirectory, "Data");
-        }
-
-        return Path.Combine(localAppData, "LanMountainDesktop");
-    }
-
     private static PluginLoaderOptions CreateOptions()
     {
         var devOptions = DevPluginOptions.Current;

LanMountainDesktop/plugins/PluginSharedContractManager.cs

@@ -257,13 +257,7 @@ internal sealed class PluginSharedContractManager : IDisposable
 
     private static string GetSharedContractRootDirectory()
     {
-        var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+        return AppDataPathProvider.GetDataRoot();
-        if (string.IsNullOrWhiteSpace(localAppData))
-        {
-            return Path.Combine(AppContext.BaseDirectory, "Data");
-        }
-
-        return Path.Combine(localAppData, "LanMountainDesktop");
     }
 
     private static string Sanitize(string value)

docs/ARCHITECTURE.md

@@ -264,5 +264,6 @@ See `docs/EXTERNAL_IPC_ARCHITECTURE.md` for the detailed contract and migration
 - `postinstall` may show OOBE only when the launcher is not elevated.
 - `plugin-install` and `debug-preview` must not auto-open OOBE.
 - Elevation is allowed only for the installer, full installer update application, and user-confirmed legacy uninstall.
-- Default plugin install should stay inside the user's LocalAppData scope and should not ask for UAC.
+- Default plugin install targets the Host data root (`AppDataPathProvider.GetDataRoot()/Extensions/Plugins`) and should not ask for UAC when that directory is writable.
-- Marketplace plugin installs are queued under the user's data root and take effect after restart; they do not use Launcher elevation.
+- In portable data mode, plugin packages follow the configured application data root. If that root is under an administrator-protected install path, Host downloads/verifies the package from a user-writable staging directory and invokes the restricted Launcher `plugin install` command with UAC to copy only into the configured data root.
+- Marketplace plugin installs are queued under the Host data root when writable and take effect after restart; protected portable installs are applied immediately through the elevated maintenance command and still require restart before loading.

docs/DEVELOPMENT.md

@@ -161,7 +161,7 @@ Use `LanMountainDesktop.slnx` as the workspace entry point. The standard loop is
 
 For packaging, see `LanMountainDesktop/PACKAGING.md`. For plugin package generation or local feed workflows, use `scripts/Pack-PluginPackages.ps1`.
 
-In-app marketplace plugin installs use a per-user pending plugin queue. The package is downloaded and verified immediately, then applied on the next Host startup before plugin discovery. `LanMountainDesktop.Launcher.exe plugin install` remains only as a maintenance compatibility command.
+In-app marketplace plugin installs use the Host data root. When `Extensions/Plugins` is writable, the package is downloaded and verified immediately, then queued and applied on the next Host startup before plugin discovery. When portable data lives under an administrator-protected install path, Host stages the download in a user-writable location and invokes the restricted `LanMountainDesktop.Launcher.exe plugin install --app-root <package-root>` maintenance command with UAC to copy into the configured data root.
 
 **Launcher Architecture**: LanMountainDesktop uses a Launcher as the single entry point, responsible for version management, updates, and launching the main application. See the Chinese section above for detailed architecture documentation.
 

docs/LAUNCHER.md

@@ -444,8 +444,10 @@ _oobeSteps = [
 - `postinstall` may open OOBE only when the launcher is not elevated and the user state path is available.
 - `plugin-install` and `debug-preview` must not auto-enter OOBE.
 - Allowed elevation paths are limited to the installer itself, full installer update application, and user-confirmed legacy uninstall.
-- Default plugin installation targets the current user's LocalAppData scope and must not request elevation by default.
+- Default plugin installation targets the Host data root and must not request elevation when that directory is writable.
-- In-app market installs are deferred Host-side operations: download and verify now, apply from the per-user pending queue on the next Host startup.
+- The Launcher `plugin install` maintenance command accepts `--app-root` so it can verify the configured data root before writing. It rejects targets outside that root.
+- In-app market installs are deferred Host-side operations when the data root is writable: download and verify now, apply from the pending queue on the next Host startup.
+- If portable data is configured under an administrator-protected install path, Host stages the package in a user-writable download directory and invokes the restricted Launcher maintenance command with UAC to copy the package into `Extensions/Plugins`.
 
 ## Public IPC Baseline