Add classic mode launcher

.github/workflows/build-release.yml

@@ -125,7 +125,7 @@ jobs:
         uses: actions/cache@v5
         with:
           path: ${{ env.NUGET_PACKAGES }}
-          key: ${{ runner.os }}-nuget-${{ hashFiles('global.json', 'src/**/*.csproj', 'src/**/*.props', 'src/**/*.targets', 'src/**/*.sln') }}
+          key: ${{ runner.os }}-nuget-${{ hashFiles('global.json', 'src/**/*.csproj', 'src/**/*.props', 'src/**/*.targets', 'src/**/*.sln', 'src/**/*.slnx') }}
           restore-keys: |
             ${{ runner.os }}-nuget-
 
@@ -160,17 +160,17 @@ jobs:
 
       - name: Restore dependencies
         working-directory: src
-        run: dotnet restore UniGetUI.sln
+        run: dotnet restore UniGetUI.Windows.slnx
 
       - name: Run tests
         working-directory: src
         shell: pwsh
         run: |
           # Retry once to handle flaky tests (e.g. TaskRecyclerTests uses Random)
-          dotnet test UniGetUI.sln --no-restore --verbosity q --nologo
+          dotnet test UniGetUI.Windows.slnx --no-restore --verbosity q --nologo /p:Platform=x64
           if ($LASTEXITCODE -ne 0) {
             Write-Host "::warning::First test run failed, retrying..."
-            dotnet test UniGetUI.sln --no-restore --verbosity q --nologo
+            dotnet test UniGetUI.Windows.slnx --no-restore --verbosity q --nologo /p:Platform=x64
             if ($LASTEXITCODE -ne 0) { exit 1 }
           }
 
@@ -188,13 +188,19 @@ jobs:
 
           $TargetFramework = "$PortableTargetFramework-windows$WindowsTargetPlatformVersion"
           dotnet publish src/UniGetUI/UniGetUI.csproj /noLogo /p:Configuration=Release /p:Platform=$Platform -p:RuntimeIdentifier=win-$Platform -v m
-          if ($LASTEXITCODE -ne 0) { throw "dotnet publish failed" }
+          if ($LASTEXITCODE -ne 0) { throw "dotnet publish WinUI failed" }
+
+          dotnet publish src/UniGetUI.Avalonia/UniGetUI.Avalonia.csproj /noLogo /p:Configuration=Release /p:Platform=$Platform -p:RuntimeIdentifier=win-$Platform --self-contained true -v m
+          if ($LASTEXITCODE -ne 0) { throw "dotnet publish Avalonia failed" }
 
           # Stage binaries
           $PublishDir = "src/UniGetUI/bin/$Platform/Release/$TargetFramework/win-$Platform/publish"
+          $AvaloniaPublishDir = "src/UniGetUI.Avalonia/bin/$Platform/Release/$TargetFramework/win-$Platform/publish"
           if (Test-Path "unigetui_bin") { Remove-Item "unigetui_bin" -Recurse -Force }
           New-Item "unigetui_bin" -ItemType Directory | Out-Null
           Get-ChildItem $PublishDir | Move-Item -Destination "unigetui_bin" -Force
+          New-Item "unigetui_bin/Avalonia" -ItemType Directory | Out-Null
+          Get-ChildItem $AvaloniaPublishDir | Move-Item -Destination "unigetui_bin/Avalonia" -Force
 
           # Backward-compat alias
           Copy-Item "unigetui_bin/UniGetUI.exe" "unigetui_bin/WingetUI.exe" -Force
@@ -330,7 +336,7 @@ jobs:
         uses: actions/cache@v5
         with:
           path: ${{ env.NUGET_PACKAGES }}
-          key: ${{ runner.os }}-nuget-${{ hashFiles('global.json', 'src/**/*.csproj', 'src/**/*.props', 'src/**/*.targets', 'src/**/*.sln') }}
+          key: ${{ runner.os }}-nuget-${{ hashFiles('global.json', 'src/**/*.csproj', 'src/**/*.props', 'src/**/*.targets', 'src/**/*.sln', 'src/**/*.slnx') }}
           restore-keys: |
             ${{ runner.os }}-nuget-
 

.github/workflows/dotnet-test.yml

@@ -57,28 +57,22 @@ jobs:
 
     - name: Install dependencies
       working-directory: src
-      run: |
-        dotnet restore UniGetUI.sln
-        dotnet restore UniGetUI.Avalonia.slnx
+      run: dotnet restore UniGetUI.Windows.slnx
 
     - name: Check whitespace formatting
       run: dotnet format whitespace src --folder --verify-no-changes --verbosity minimal
 
-    - name: Check code style formatting (WinUI solution)
+    - name: Check code style formatting (Windows solution)
       working-directory: src
-      run: dotnet format style UniGetUI.sln --no-restore --verify-no-changes --verbosity minimal
+      run: dotnet format style UniGetUI.Windows.slnx --no-restore --verify-no-changes --verbosity minimal
 
-    - name: Check code style formatting (Avalonia solution)
+    - name: Build Windows solution
       working-directory: src
-      run: dotnet format style UniGetUI.Avalonia.slnx --no-restore --verify-no-changes --verbosity minimal
-
-    - name: Build Avalonia solution
-      working-directory: src
-      run: dotnet build UniGetUI.Avalonia.slnx --no-restore --verbosity minimal
+      run: dotnet build UniGetUI.Windows.slnx --no-restore --verbosity minimal /p:Platform=x64
 
     - name: Run Tests
       working-directory: src
       env:
         GITHUB_TOKEN: ${{ github.token }}
-      run: dotnet test UniGetUI.sln --no-restore --verbosity q --nologo
+      run: dotnet test UniGetUI.Windows.slnx --no-restore --verbosity q --nologo /p:Platform=x64
 

AGENTS.md

@@ -5,7 +5,7 @@
 UniGetUI is a WinUI 3 desktop app (C#/.NET 10, Windows App SDK) providing a GUI for CLI package managers (WinGet, Scoop, Chocolatey, Pip, Npm, .NET Tool, PowerShell Gallery, Cargo, Vcpkg).
 
 Solution entry points:
-- `src/UniGetUI.sln` - official Windows application based on WinUI 3
+- `src/UniGetUI.Windows.slnx` - official Windows solution; builds the WinUI 3 launcher/classic app and the Avalonia app
 - `src/UniGetUI.Avalonia.slnx` - experimental cross-platform Avalonia port
 
 ## Architecture
@@ -94,7 +94,7 @@ Use `CoreTools.Translate("text")` for all user-facing strings. Parameterized: `C
 
 | Purpose | Path |
 |---|---|
-| Solution | `src/UniGetUI.sln` |
+| Windows solution | `src/UniGetUI.Windows.slnx` |
 | Experimental cross-platform solution | `src/UniGetUI.Avalonia.slnx` |
 | Shared build props | `src/Directory.Build.props` |
 | Version info | `src/SharedAssemblyInfo.cs` |

CONTRIBUTING.md

@@ -41,9 +41,9 @@ Before reading: All of the rules below are guidelines, which means that they sho
 ## Formatting:
  - Run `pwsh ./scripts/install-git-hooks.ps1` once after cloning to enable the repository pre-commit hook.
 - The pre-commit hook runs `dotnet format whitespace src --folder` on staged files under `src` when the `dotnet` CLI is available, and stops the commit if it had to rewrite files so you can review the changes and commit again.
- - CI enforces whitespace formatting with `dotnet format whitespace src --folder --verify-no-changes` and code-style verification with `dotnet format style src/UniGetUI.sln --no-restore --verify-no-changes` in `.github/workflows/dotnet-test.yml`.
+- CI enforces whitespace formatting with `dotnet format whitespace src --folder --verify-no-changes` and code-style verification with `dotnet format style src/UniGetUI.Windows.slnx --no-restore --verify-no-changes` in `.github/workflows/dotnet-test.yml`.
  - The pre-commit hook intentionally does not run `dotnet format style` because solution loading makes it take roughly the same time for one staged C# file as for the full solution.
- - If you want to check the same style rules locally before pushing, run `dotnet format style src/UniGetUI.sln --no-restore --verify-no-changes` from the repository root.
+- If you want to check the same style rules locally before pushing, run `dotnet format style src/UniGetUI.Windows.slnx --no-restore --verify-no-changes` from the repository root.
  - If you want to prepare a dedicated formatting-only commit, run `dotnet format whitespace src --folder` from the repository root.
 
 ## Coding:

scripts/build.ps1

@@ -37,7 +37,9 @@ $ErrorActionPreference = 'Stop'
 
 $RepoRoot = Resolve-Path (Join-Path $PSScriptRoot "..")
 $SrcDir = Join-Path $RepoRoot "src"
+$WindowsSolution = Join-Path $SrcDir "UniGetUI.Windows.slnx"
 $PublishProject = Join-Path $SrcDir "UniGetUI" "UniGetUI.csproj"
+$AvaloniaPublishProject = Join-Path $SrcDir "UniGetUI.Avalonia" "UniGetUI.Avalonia.csproj"
 $BinDir = Join-Path $RepoRoot "unigetui_bin"
 $BuildPropsPath = Join-Path $SrcDir "Directory.Build.props"
 [xml] $BuildProps = Get-Content $BuildPropsPath
@@ -50,6 +52,7 @@ if ([string]::IsNullOrWhiteSpace($PortableTargetFramework) -or [string]::IsNullO
 
 $TargetFramework = "$PortableTargetFramework-windows$WindowsTargetPlatformVersion"
 $PublishDir = Join-Path $SrcDir "UniGetUI" "bin" $Platform $Configuration $TargetFramework "win-$Platform" "publish"
+$AvaloniaPublishDir = Join-Path $SrcDir "UniGetUI.Avalonia" "bin" $Platform $Configuration $TargetFramework "win-$Platform" "publish"
 
 # --- Version stamping ---
 if ($Version) {
@@ -66,26 +69,34 @@ Write-Host "Building UniGetUI version: $PackageVersion"
 # --- Test ---
 if (-not $SkipTests) {
     Write-Host "`n=== Running tests ===" -ForegroundColor Cyan
-    dotnet test (Join-Path $SrcDir "UniGetUI.sln") --verbosity q --nologo --ignore-failed-sources
+    dotnet test $WindowsSolution --verbosity q --nologo --ignore-failed-sources /p:Platform=$Platform
     if ($LASTEXITCODE -ne 0) {
         throw "Tests failed with exit code $LASTEXITCODE"
     }
 }
 
 # --- Build / Publish ---
 Write-Host "`n=== Publishing $Configuration|$Platform ===" -ForegroundColor Cyan
-dotnet clean (Join-Path $SrcDir "UniGetUI.sln") -v m --nologo
+dotnet clean $WindowsSolution -v m --nologo /p:Platform=$Platform
 
 dotnet publish $PublishProject /noLogo /p:Configuration=$Configuration /p:Platform=$Platform --ignore-failed-sources -v m
 if ($LASTEXITCODE -ne 0) {
-    throw "dotnet publish failed with exit code $LASTEXITCODE"
+    throw "dotnet publish WinUI failed with exit code $LASTEXITCODE"
+}
+
+dotnet publish $AvaloniaPublishProject /noLogo /p:Configuration=$Configuration /p:Platform=$Platform -p:RuntimeIdentifier=win-$Platform --self-contained true --ignore-failed-sources -v m
+if ($LASTEXITCODE -ne 0) {
+    throw "dotnet publish Avalonia failed with exit code $LASTEXITCODE"
 }
 
 # --- Stage binaries ---
 if (Test-Path $BinDir) { Remove-Item $BinDir -Recurse -Force }
 New-Item $BinDir -ItemType Directory | Out-Null
 # Move published output into unigetui_bin
 Get-ChildItem $PublishDir | Move-Item -Destination $BinDir -Force
+$AvaloniaBinDir = Join-Path $BinDir "Avalonia"
+New-Item $AvaloniaBinDir -ItemType Directory | Out-Null
+Get-ChildItem $AvaloniaPublishDir | Move-Item -Destination $AvaloniaBinDir -Force
 
 # WingetUI.exe alias for backward compat
 Copy-Item (Join-Path $BinDir "UniGetUI.exe") (Join-Path $BinDir "WingetUI.exe") -Force

src/Languages/lang_en.json

@@ -380,6 +380,8 @@
   "Follow system color scheme": "Follow system color scheme",
   "Application theme:": "Application theme:",
   "UniGetUI startup page:": "UniGetUI startup page:",
+  "Use classic mode": "Use classic mode",
+  "Restart UniGetUI to apply this change": "Restart UniGetUI to apply this change",
   "Proxy settings": "Proxy settings",
   "Other settings": "Other settings",
   "Connect the internet using a custom proxy": "Connect the internet using a custom proxy",

src/UniGetUI.Avalonia/App.axaml.cs

@@ -65,6 +65,8 @@ public override void OnFrameworkInitializationCompleted()
             ApplyTheme(CoreSettings.GetValue(CoreSettings.K.PreferredTheme));
             var mainWindow = new MainWindow();
             desktop.MainWindow = mainWindow;
+            Program.SecondaryInstanceArgsReceived += args =>
+                HandleSecondaryInstanceArgs(mainWindow, args);
 
             if (CoreData.WasDaemon)
             {
@@ -139,6 +141,20 @@ private static async Task StartupAsync(MainWindow mainWindow)
         await AvaloniaBootstrapper.InitializeAsync();
     }
 
+    private static void HandleSecondaryInstanceArgs(MainWindow mainWindow, string[] args)
+    {
+        bool isDaemonLaunch = args.Contains(AvaloniaCliHandler.DAEMON);
+        CoreData.IsDaemon = isDaemonLaunch;
+
+        if (isDaemonLaunch)
+            return;
+
+        if (!mainWindow.IsVisible)
+            mainWindow.Show();
+
+        mainWindow.Activate();
+    }
+
     public static void ApplyTheme(string value)
     {
         Current!.RequestedThemeVariant = value switch

src/UniGetUI.Avalonia/Infrastructure/AppRestartHelper.cs

@@ -0,0 +1,75 @@
+using System.Diagnostics;
+using Avalonia.Controls.ApplicationLifetimes;
+using UniGetUI.Avalonia.Views;
+
+namespace UniGetUI.Avalonia.Infrastructure;
+
+internal static class AppRestartHelper
+{
+    private const string LauncherExecutableName = "UniGetUI.exe";
+
+    public static void Restart()
+    {
+        string executablePath = ResolveRestartExecutablePath(AppContext.BaseDirectory);
+        Process.Start(new ProcessStartInfo(executablePath)
+        {
+            UseShellExecute = false,
+        });
+
+        if (MainWindow.Instance is { } mainWindow)
+        {
+            mainWindow.QuitApplication();
+            return;
+        }
+
+        (global::Avalonia.Application.Current?.ApplicationLifetime
+            as IClassicDesktopStyleApplicationLifetime)?.Shutdown();
+    }
+
+    internal static string ResolveRestartExecutablePath(string baseDirectory)
+    {
+        if (!OperatingSystem.IsWindows())
+            return Environment.ProcessPath
+                ?? throw new InvalidOperationException("Could not resolve the current executable path.");
+
+        foreach (string candidate in GetWindowsLauncherCandidates(baseDirectory))
+        {
+            if (File.Exists(candidate))
+                return candidate;
+        }
+
+        return Environment.ProcessPath
+            ?? throw new FileNotFoundException(
+                $"Could not find the UniGetUI launcher '{LauncherExecutableName}'."
+            );
+    }
+
+    private static IEnumerable<string> GetWindowsLauncherCandidates(string baseDirectory)
+    {
+        yield return Path.Combine(baseDirectory, "..", LauncherExecutableName);
+        yield return Path.Combine(baseDirectory, LauncherExecutableName);
+
+        var directory = new DirectoryInfo(Path.GetFullPath(baseDirectory));
+        while (directory is not null)
+        {
+            string launcherBinDirectory = Path.Combine(directory.FullName, "UniGetUI", "bin");
+            if (Directory.Exists(launcherBinDirectory))
+            {
+                foreach (
+                    string candidate in Directory
+                        .EnumerateFiles(
+                            launcherBinDirectory,
+                            LauncherExecutableName,
+                            SearchOption.AllDirectories
+                        )
+                        .OrderByDescending(File.GetLastWriteTimeUtc)
+                )
+                {
+                    yield return candidate;
+                }
+            }
+
+            directory = directory.Parent;
+        }
+    }
+}

src/UniGetUI.Avalonia/Program.cs

@@ -1,11 +1,17 @@
 using System;
 using Avalonia;
+using UniGetUI.Avalonia.Infrastructure;
 using UniGetUI.Core.Data;
+using UniGetUI.Core.Logging;
 
 namespace UniGetUI.Avalonia;
 
 sealed class Program
 {
+    private static Mutex? _singleInstanceMutex;
+
+    internal static event Action<string[]>? SecondaryInstanceArgsReceived;
+
     // Initialization code. Don't use any Avalonia, third-party APIs or any
     // SynchronizationContext-reliant code before AppMain is called: things aren't initialized
     // yet and stuff might break.
@@ -25,9 +31,42 @@ public static void Main(string[] args)
 
         CoreData.WasDaemon = CoreData.IsDaemon = args.Contains(AvaloniaCliHandler.DAEMON);
 
+        if (!TryRegisterSingleInstance(args))
+            return;
+
         BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
     }
 
+    private static bool TryRegisterSingleInstance(string[] args)
+    {
+        if (!OperatingSystem.IsWindows())
+            return true;
+
+        _singleInstanceMutex = new Mutex(
+            initiallyOwned: true,
+            name: CoreData.MainWindowIdentifier,
+            createdNew: out bool createdNew
+        );
+
+        if (createdNew)
+        {
+            SingleInstanceRedirector.StartListener(args =>
+                SecondaryInstanceArgsReceived?.Invoke(args)
+            );
+            return true;
+        }
+
+        if (SingleInstanceRedirector.TryForwardToFirstInstance(args))
+        {
+            _singleInstanceMutex.Dispose();
+            _singleInstanceMutex = null;
+            return false;
+        }
+
+        Logger.Warn("Could not redirect to the existing Avalonia instance; starting a new one");
+        return true;
+    }
+
     // Avalonia configuration, don't remove; also used by visual designer.
     public static AppBuilder BuildAvaloniaApp()
         => AppBuilder.Configure<App>()

src/UniGetUI.Avalonia/UniGetUI.Avalonia.csproj

@@ -87,6 +87,7 @@
     <ItemGroup>
       <Compile Remove="Infrastructure\**" />
       <Compile Include="Infrastructure\AvaloniaOperationRegistry.cs" />
+      <Compile Include="Infrastructure\AppRestartHelper.cs" />
       <Compile Include="Infrastructure\WindowsAppNotificationBridge.cs" />
       <Compile Include="Infrastructure\WindowsTrayService.cs" Condition="$([MSBuild]::IsOSPlatform('Windows'))" />
       <Compile Include="Infrastructure\MacOsNotificationBridge.cs" />

src/UniGetUI.Avalonia/ViewModels/Pages/SettingsPages/SettingsBasePageViewModel.cs

@@ -1,6 +1,6 @@
-using Avalonia.Controls.ApplicationLifetimes;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using UniGetUI.Avalonia.Infrastructure;
 using UniGetUI.Avalonia.ViewModels;
 using UniGetUI.Core.Tools;
 
@@ -22,12 +22,6 @@ public partial class SettingsBasePageViewModel : ViewModelBase
     [RelayCommand]
     private static void RestartApp()
     {
-        var exe = Environment.ProcessPath;
-        if (exe is not null)
-            System.Diagnostics.Process.Start(
-                new System.Diagnostics.ProcessStartInfo(exe) { UseShellExecute = true });
-        (global::Avalonia.Application.Current?.ApplicationLifetime
-            as IClassicDesktopStyleApplicationLifetime)
-            ?.Shutdown();
+        AppRestartHelper.Restart();
     }
 }