feat(i18n): add Traditional and Simplified Chinese UI localization

README.md

@@ -46,6 +46,7 @@ Windows. Test your ISO in a VM before installing it.**
 ## More information
 
 [Usage, compatibility and build instructions](docs/usage.md) ·
+[Interface translations](docs/translations.md) ·
 [Attribution and distribution notes](NOTICE.md)
 
 The original PowerShell builders remain in this repository.

docs/translations.md

@@ -0,0 +1,36 @@
+# Interface translations
+
+The WinUI app resolves its interface text through `Strings\<language>\Resources.resw`.
+English is the source language; every other language must contain the same keys.
+
+| Language | Tag | File |
+| --- | --- | --- |
+| English | `en-US` | `src/Tiny11Builder.App/Strings/en-US/Resources.resw` |
+| Traditional Chinese | `zh-Hant` | `src/Tiny11Builder.App/Strings/zh-Hant/Resources.resw` |
+| Simplified Chinese | `zh-Hans` | `src/Tiny11Builder.App/Strings/zh-Hans/Resources.resw` |
+
+Choose a language under **Language** in the sidebar. The choice is saved in
+`%LOCALAPPDATA%\Tiny11Builder\settings.json` and applied after a restart, because
+XAML resolves its text when a page is loaded.
+
+## Add a language
+
+1. Copy `Strings\en-US\Resources.resw` to `Strings\<tag>\Resources.resw`, using a
+   BCP-47 tag such as `ja-JP` or `de-DE`.
+2. Translate every value. Keep the `name` attributes and the `{0}` placeholders
+   unchanged; a placeholder may move within a sentence.
+3. Add the tag and its native name to `LanguageCatalog.All` in
+   `src/Tiny11Builder.App/LanguageCatalog.cs`.
+4. Run `dotnet test tests/Tiny11Builder.Core.Tests`. `LocalizationTests` checks
+   that every language has exactly the English keys, no empty values, and the
+   same placeholders, and that every `{loc:Tr Key=…}` used by XAML exists.
+
+Keys are flat and use `__` between words (`Build__Result__Saved`). A key must not
+be a prefix of another key: MRT treats dots as resource-map separators, so flat
+keys keep a resource from also becoming a scope.
+
+## What stays English
+
+Build-engine operation names, stage status words, the raw build recipe and the
+build log are technical diagnostics. They are not translated by these files; the
+interactive interface, removal catalog and user-facing notices are.

docs/usage.md

@@ -341,6 +341,17 @@ as an unsupported operation. Removing a service deletes its offline registry
 registration; shared `svchost.exe` and other shared binaries are never blindly
 deleted. Test aggressive images in an isolated VM and keep known-good media.
 
+## Interface languages
+
+The app ships with English, Traditional Chinese (`zh-Hant`) and Simplified
+Chinese (`zh-Hans`). Choose a language under **Language** in the sidebar; the
+choice is saved and applied after a restart. The interface, removal catalog and
+user-facing notices are translated. Build-engine operation names, stage status
+words, the raw recipe and the build log remain English technical text.
+
+See [translations.md](translations.md) for the resource layout and the steps to
+add another language.
+
 ## Build and run
 
 Requirements: Windows 10 2004 or newer as the host, .NET 8 SDK and a Windows SDK

src/Tiny11Builder.App/App.xaml.cs

@@ -1,11 +1,22 @@
 using Microsoft.UI.Xaml;
+using Microsoft.Windows.Globalization;
 
 namespace Tiny11Builder.App;
 
 public partial class App : Application
 {
     private Window? window;
-    public App() => InitializeComponent();
+
+    public App()
+    {
+        // The override must be in place before any XAML is loaded: markup-extension text is resolved
+        // when a page is parsed, not when the window is shown.
+        var language = LanguageCatalog.Normalize(AppSettings.Load().Language);
+        if (language.Length > 0) ApplicationLanguages.PrimaryLanguageOverride = language;
+        InitializeComponent();
+        ResourceProvider.Install();
+    }
+
     protected override void OnLaunched(LaunchActivatedEventArgs args)
     {
         window = new MainWindow();

src/Tiny11Builder.App/AppSettings.cs

@@ -0,0 +1,30 @@
+using System.Text.Json;
+
+namespace Tiny11Builder.App;
+
+// The only user setting the app owns. It lives beside the downloaded tools, never in the build
+// workspace, so a recovered or discarded job cannot change the interface language.
+internal sealed class AppSettings
+{
+    private static readonly string FilePath = Path.Combine(
+        Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Tiny11Builder", "settings.json");
+
+    public string Language { get; set; } = "";
+
+    public static AppSettings Load()
+    {
+        try { return JsonSerializer.Deserialize<AppSettings>(File.ReadAllText(FilePath)) ?? new(); }
+        catch (Exception error) when (error is IOException or UnauthorizedAccessException or JsonException) { return new(); }
+    }
+
+    public bool TrySave()
+    {
+        try
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(FilePath)!);
+            File.WriteAllText(FilePath, JsonSerializer.Serialize(this));
+            return true;
+        }
+        catch (Exception error) when (error is IOException or UnauthorizedAccessException) { return false; }
+    }
+}

src/Tiny11Builder.App/Choices.cs

@@ -24,9 +24,16 @@ public sealed class OptionChoice(CleanupOption option) : ObservableChoice
 {
     private bool selected = option.Balanced;
     public CleanupOption Option { get; } = option;
-    public string Title => Option.Title;
-    public string Description => Option.Description;
-    public string Category => Option.Category;
+    public string Title => Loc.Get($"Catalog__{Option.Id}__Title");
+    public string Description => Loc.Get($"Catalog__{Option.Id}__Description");
+    public string Category => Option.Category switch
+    {
+        "Bundled apps" => Loc.Get("Catalog__Category__Apps"),
+        "Optional features" => Loc.Get("Catalog__Category__Features"),
+        "Windows settings" => Loc.Get("Catalog__Category__Settings"),
+        "Advanced / original builder" => Loc.Get("Catalog__Category__Advanced"),
+        _ => Option.Category
+    };
     public bool Selected { get => selected; set => Set(ref selected, value); }
 }
 
@@ -37,10 +44,10 @@ public sealed class InventoryChoice(ImageInventoryItem item) : ObservableChoice
     public ImageInventoryItem Item { get; } = item;
     public string Title => Item.Identity;
     public string Detail => $"{Item.Kind} · {Item.Detail}";
-    public string Risk => Item.Protected ? "Protected / potentially boot-critical" : "Application";
-    public string ModeLabel => $"Action for {Title}";
+    public string Risk => Loc.Get(Item.Protected ? "Components__Inventory__Protected" : "Components__Inventory__Application");
+    public string ModeLabel => Loc.Format("Components__Inventory__ActionFor", Title);
     public bool HasModes => Item.Kind is ImageItemKind.Service or ImageItemKind.Feature;
-    public string[] Modes { get; } = ["Disable", "Remove"];
+    public string[] Modes { get; } = [Loc.Get("Components__Inventory__Disable"), Loc.Get("Components__Inventory__Remove")];
     public bool Selected { get => selected; set => Set(ref selected, value); }
     public int ModeIndex { get => modeIndex; set => Set(ref modeIndex, value); }
     public ExpertAction Action => new(Item.Kind, Item.Identity, ModeIndex == 0 ? ExpertActionMode.Disable : ExpertActionMode.Remove);
@@ -52,8 +59,8 @@ public sealed class BuildStageBoard
 {
     public BuildStageChoice[] Stages { get; } =
     [
-        new("Prepare media", "\uE8B7"), new("Export and mount", "\uE7C5"), new("Remove components", "\uE74D"),
-        new("Commit image", "\uE74E"), new("Compress image", "\uE8B9"), new("Create ISO", "\uE958"), new("Verify output", "\uE73E")
+        new(Loc.Get("Build__Board__Prepare"), "\uE8B7"), new(Loc.Get("Build__Board__Export"), "\uE7C5"), new(Loc.Get("Build__Board__Remove"), "\uE74D"),
+        new(Loc.Get("Build__Board__Commit"), "\uE74E"), new(Loc.Get("Build__Board__Compress"), "\uE8B9"), new(Loc.Get("Build__Board__Iso"), "\uE958"), new(Loc.Get("Build__Board__Verify"), "\uE73E")
     ];
 
     // Returns the phase the event belongs to, or -1 when it is not a displayed operation.

src/Tiny11Builder.App/LanguageCatalog.cs

@@ -0,0 +1,39 @@
+namespace Tiny11Builder.App;
+
+internal sealed record AppLanguage(string Tag, string NativeName)
+{
+    // The system choice has no native name of its own; it is the one label that follows the UI language.
+    public string DisplayName => Tag.Length == 0 ? Loc.Get("Language__System") : NativeName;
+}
+
+internal static class LanguageCatalog
+{
+    // Tags match the Strings\<tag>\Resources.resw folders. English is the fallback and must stay first.
+    public static IReadOnlyList<AppLanguage> All { get; } =
+    [
+        new("", ""),
+        new("en-US", "English"),
+        new("zh-Hant", "繁體中文"),
+        new("zh-Hans", "简体中文"),
+    ];
+
+    public static string Normalize(string? tag)
+    {
+        if (string.IsNullOrWhiteSpace(tag)) return "";
+        var exact = All.FirstOrDefault(language => language.Tag.Equals(tag, StringComparison.OrdinalIgnoreCase));
+        if (exact is not null) return exact.Tag;
+        return tag.ToLowerInvariant() switch
+        {
+            "zh-tw" or "zh-hk" or "zh-mo" or "zh-hant" => "zh-Hant",
+            "zh-cn" or "zh-sg" or "zh-hans" => "zh-Hans",
+            "en" => "en-US",
+            _ => ""
+        };
+    }
+
+    public static AppLanguage For(string? tag)
+    {
+        var normalized = Normalize(tag);
+        return All.First(language => language.Tag == normalized);
+    }
+}

src/Tiny11Builder.App/Localization.cs

@@ -0,0 +1,19 @@
+using System.Globalization;
+
+namespace Tiny11Builder.App;
+
+// UI text is resolved through this one seam. The app installs the Windows resource lookup at startup;
+// the tests install the English resources, so the same code runs in both and no English copy is
+// duplicated in C#.
+internal static class Loc
+{
+    private static Func<string, string?>? lookup;
+
+    public static void Use(Func<string, string?> resolver) => lookup = resolver;
+
+    public static string Get(string key) =>
+        lookup?.Invoke(key) is { Length: > 0 } text ? text : key;
+
+    public static string Format(string key, params object?[] values) =>
+        string.Format(CultureInfo.CurrentCulture, Get(key), values);
+}