Make Avalonia frontend the default

src/UniGetUI.Avalonia/Views/Pages/SettingsPages/Interface_P.axaml

@@ -27,7 +27,7 @@
 
             <Border Height="16"/>
 
-            <settings:CheckboxCard SettingName="DisableClassicMode"
+            <settings:CheckboxCard SettingName="UseClassicMode"
                                    Text="{t:Translate Use classic mode}"
                                    WarningText="{t:Translate Restart UniGetUI to apply this change}"
                                    StateChangedCommand="{Binding ShowRestartRequiredCommand}"

src/UniGetUI.Core.Settings/SettingsEngine_Names.cs

@@ -91,6 +91,7 @@ public enum K
         WinGetComApiPolicy,
         WinGetDownloadFullManifest,
         DisableClassicMode,
+        UseClassicMode,
         DisableInstallerHostChangeWarning,
         BunPreferLatestVersions,
         RedactUsernameInLog,
@@ -198,6 +199,7 @@ public static string ResolveKey(K key)
             K.WinGetComApiPolicy => "WinGetComApiPolicy",
             K.WinGetDownloadFullManifest => "WinGetDownloadFullManifest",
             K.DisableClassicMode => "DisableClassicMode",
+            K.UseClassicMode => "UseClassicMode",
             K.DisableInstallerHostChangeWarning => "DisableInstallerHostChangeWarning",
             K.BunPreferLatestVersions => "BunPreferLatestVersions",
             K.RedactUsernameInLog => "RedactUsernameInLog",

src/UniGetUI.Tests/ModernAppLauncherTests.cs

@@ -1,3 +1,4 @@
+using System.Runtime.InteropServices;
 using UniGetUI.Core.Data;
 using UniGetUI.Core.SettingsEngine;
 
@@ -28,25 +29,35 @@ public void Dispose()
     }
 
     [Fact]
-    public void ClassicModeDefaultsToEnabled()
+    public void ClassicModeDefaultsToDisabled()
     {
-        Assert.True(ModernAppLauncher.IsClassicModeEnabled());
+        Assert.False(ModernAppLauncher.IsClassicModeEnabled());
 
-        Settings.Set(Settings.K.DisableClassicMode, true);
+        Settings.Set(Settings.K.UseClassicMode, true);
 
-        Assert.False(ModernAppLauncher.IsClassicModeEnabled());
+        Assert.True(ModernAppLauncher.IsClassicModeEnabled());
     }
 
     [Fact]
-    public void BetaTestersDefaultToModernUI()
+    public void BetaTestersAlwaysUseModernUI()
     {
+        Settings.Set(Settings.K.UseClassicMode, true);
+
         Assert.True(ModernAppLauncher.IsClassicModeEnabled());
 
         Settings.Set(Settings.K.EnableUniGetUIBeta, true);
 
         Assert.False(ModernAppLauncher.IsClassicModeEnabled());
     }
 
+    [Fact]
+    public void LegacyDisableClassicModeSettingDoesNotEnableClassicMode()
+    {
+        Settings.Set(Settings.K.DisableClassicMode, true);
+
+        Assert.False(ModernAppLauncher.IsClassicModeEnabled());
+    }
+
     [Fact]
     public void ResolveModernExecutablePath_PrefersRootExecutable()
     {
@@ -107,6 +118,57 @@ public void ResolveModernExecutablePath_FindsDevelopmentBuildOutput()
         Assert.Equal(expected, ModernAppLauncher.ResolveModernExecutablePath(baseDirectory));
     }
 
+    [Fact]
+    public void ResolveModernExecutablePath_PrefersCurrentArchitectureDevelopmentBuildOutput()
+    {
+        string baseDirectory = Path.Combine(
+            _testRoot,
+            "UniGetUI",
+            "bin",
+            "x64",
+            "Debug",
+            "net10.0-windows10.0.26100.0",
+            "win-x64"
+        );
+        Directory.CreateDirectory(baseDirectory);
+
+        string currentRuntimeIdentifier = RuntimeInformation.ProcessArchitecture switch
+        {
+            Architecture.X64 => "win-x64",
+            Architecture.Arm64 => "win-arm64",
+            Architecture.X86 => "win-x86",
+            Architecture.Arm => "win-arm",
+            _ => "win-x64",
+        };
+        string otherRuntimeIdentifier = currentRuntimeIdentifier == "win-x64"
+            ? "win-arm64"
+            : "win-x64";
+
+        string expected = CreateAvaloniaDevelopmentExecutable(currentRuntimeIdentifier);
+        string other = CreateAvaloniaDevelopmentExecutable(otherRuntimeIdentifier);
+
+        File.SetLastWriteTimeUtc(expected, DateTime.UtcNow.AddMinutes(-5));
+        File.SetLastWriteTimeUtc(other, DateTime.UtcNow);
+
+        Assert.Equal(expected, ModernAppLauncher.ResolveModernExecutablePath(baseDirectory));
+    }
+
+    private string CreateAvaloniaDevelopmentExecutable(string runtimeIdentifier)
+    {
+        string path = Path.Combine(
+            _testRoot,
+            "UniGetUI.Avalonia",
+            "bin",
+            "Debug",
+            "net10.0-windows10.0.26100.0",
+            runtimeIdentifier,
+            ModernAppLauncher.ModernAppExecutableName
+        );
+        Directory.CreateDirectory(Path.GetDirectoryName(path)!);
+        File.WriteAllText(path, "");
+        return path;
+    }
+
     [Fact]
     public void CreateStartInfo_PreservesArguments()
     {

src/UniGetUI/ModernAppLauncher.cs

@@ -1,4 +1,5 @@
 using System.Diagnostics;
+using System.Runtime.InteropServices;
 using UniGetUI.Core.Logging;
 using UniGetUI.Core.SettingsEngine;
 
@@ -10,7 +11,7 @@ internal static class ModernAppLauncher
     internal const string ModernAppExecutableName = "UniGetUI.Avalonia.exe";
 
     public static bool IsClassicModeEnabled() =>
-        !Settings.Get(Settings.K.DisableClassicMode) && !Settings.Get(Settings.K.EnableUniGetUIBeta);
+        Settings.Get(Settings.K.UseClassicMode) && !Settings.Get(Settings.K.EnableUniGetUIBeta);
 
     public static void Launch(string[] args)
     {
@@ -89,7 +90,8 @@ string candidate in Directory
                             ModernAppExecutableName,
                             SearchOption.AllDirectories
                         )
-                        .OrderByDescending(File.GetLastWriteTimeUtc)
+                        .OrderByDescending(IsCurrentRuntimeCandidate)
+                        .ThenByDescending(File.GetLastWriteTimeUtc)
                 )
                 {
                     yield return candidate;
@@ -99,4 +101,22 @@ string candidate in Directory
             directory = directory.Parent;
         }
     }
+
+    private static bool IsCurrentRuntimeCandidate(string candidate)
+    {
+        string runtimeIdentifier = RuntimeInformation.ProcessArchitecture switch
+        {
+            Architecture.X64 => "win-x64",
+            Architecture.Arm64 => "win-arm64",
+            Architecture.X86 => "win-x86",
+            Architecture.Arm => "win-arm",
+            _ => "",
+        };
+
+        return runtimeIdentifier.Length > 0
+            && candidate.Contains(
+                $"{Path.DirectorySeparatorChar}{runtimeIdentifier}{Path.DirectorySeparatorChar}",
+                StringComparison.OrdinalIgnoreCase
+            );
+    }
 }

src/UniGetUI/Pages/SettingsPages/GeneralPages/Interface_P.xaml

@@ -40,7 +40,7 @@
       <UserControl Height="16" />
       <widgets:CheckboxCard
         CornerRadius="8"
-        SettingName="DisableClassicMode"
+        SettingName="UseClassicMode"
         StateChanged="ShowRestartBanner"
         Text="Use classic mode"
         WarningText="Restart UniGetUI to apply this change"