Fix WASM compatibility issues and arrow selection rendering bug

- Fix arrow selection line count calculation (overcounted by 1 due to
  trailing newline, causing progressive line truncation on each redraw)
- Replace sync Loreline bridge with queue-based async pattern to avoid
  "Cannot wait on monitors" WASM deadlock
- Add bounded input buffer (8 keys, DropOldest) to prevent held-key
  accumulation
- Set Spectre.Console Profile.Height on all AnsiConsole.Create calls to
  prevent PlatformNotSupportedException on Console.WindowHeight
- Add explicit Loreline.dll reference + TrimmerRootAssembly for WASM
- Use MSBuild CopyGameContent target instead of Content/Link for static
  file serving in Blazor WASM
- Add WASM guards for file I/O in ContentRegistry, LocalizationManager,
  AdventureEngine
- Enforce min 120x30 terminal dimensions in xterm.js
- Add Playwright E2E tests (6 tests: page load, language selection,
  full flow, multi-box progression, extended play, adventure)

.gitignore

@@ -44,3 +44,6 @@ Thumbs.db
 .claude/
 
 builds
+
+## Web project: content files copied by build target (source of truth is content/)
+src/OpenTheBox.Web/wwwroot/content/

OpenTheBox.slnx

@@ -5,5 +5,6 @@
   </Folder>
   <Folder Name="/tests/">
     <Project Path="tests/OpenTheBox.Tests/OpenTheBox.Tests.csproj" />
+    <Project Path="tests/OpenTheBox.Web.Tests/OpenTheBox.Web.Tests.csproj" />
   </Folder>
 </Solution>

src/OpenTheBox.Web/OpenTheBox.Web.csproj

@@ -16,20 +16,30 @@
     <ProjectReference Include="..\OpenTheBox\OpenTheBox.csproj" />
   </ItemGroup>
 
-  <!-- Copy game content files to wwwroot for HTTP loading -->
+  <!-- Loreline DLL: must be explicitly referenced for WASM (transitive ref from OpenTheBox doesn't resolve for browser-wasm) -->
   <ItemGroup>
-    <Content Include="..\..\content\data\**\*">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-      <Link>wwwroot\content\data\%(RecursiveDir)%(Filename)%(Extension)</Link>
-    </Content>
-    <Content Include="..\..\content\adventures\**\*">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-      <Link>wwwroot\content\adventures\%(RecursiveDir)%(Filename)%(Extension)</Link>
-    </Content>
-    <Content Include="..\..\content\strings\**\*">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-      <Link>wwwroot\content\strings\%(RecursiveDir)%(Filename)%(Extension)</Link>
-    </Content>
+    <Reference Include="Loreline">
+      <HintPath>..\..\lib\Loreline.dll</HintPath>
+    </Reference>
+    <TrimmerRootAssembly Include="Loreline" />
   </ItemGroup>
 
+  <!-- Copy game content files into wwwroot before build so Blazor serves them as static files -->
+  <Target Name="CopyGameContent" BeforeTargets="BeforeBuild">
+    <ItemGroup>
+      <GameDataFiles Include="$(MSBuildProjectDirectory)\..\..\content\data\**\*" />
+      <GameAdventureFiles Include="$(MSBuildProjectDirectory)\..\..\content\adventures\**\*" />
+      <GameStringFiles Include="$(MSBuildProjectDirectory)\..\..\content\strings\**\*" />
+    </ItemGroup>
+    <Copy SourceFiles="@(GameDataFiles)"
+          DestinationFiles="@(GameDataFiles->'$(MSBuildProjectDirectory)\wwwroot\content\data\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
+    <Copy SourceFiles="@(GameAdventureFiles)"
+          DestinationFiles="@(GameAdventureFiles->'$(MSBuildProjectDirectory)\wwwroot\content\adventures\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
+    <Copy SourceFiles="@(GameStringFiles)"
+          DestinationFiles="@(GameStringFiles->'$(MSBuildProjectDirectory)\wwwroot\content\strings\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
+  </Target>
+
 </Project>

src/OpenTheBox.Web/Program.cs

@@ -20,6 +20,14 @@ public static class Program
         var http = host.Services.GetRequiredService<HttpClient>();
 
         var gameHost = new WebGameHost(js, http);
-        await gameHost.RunAsync();
+        try
+        {
+            await gameHost.RunAsync();
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[OpenTheBox] Fatal error: {ex}");
+            throw;
+        }
     }
 }

src/OpenTheBox.Web/WebGameHost.cs

@@ -129,7 +129,7 @@ public sealed class WebGameHost
         if (_locStrings.TryGetValue(key, out string? json))
             _loc.LoadFromString(locale, json);
         else
-            _loc.Change(locale); // fallback to file-based (will fail gracefully in WASM)
+            _loc.LoadFromString(locale, "{}"); // no file I/O in WASM — use empty strings as fallback
     }
 
     // ── Main menu ────────────────────────────────────────────────────────
@@ -592,6 +592,7 @@ public sealed class WebGameHost
                 ColorSystem = ColorSystemSupport.TrueColor
             });
             bufferConsole.Profile.Width = WebTerminal.Width;
+            bufferConsole.Profile.Height = WebTerminal.Height;
 
             bufferConsole.Write(InventoryPanel.Render(_state, _registry, _loc, scrollOffset, selectedIndex: selectedIndex));
 
@@ -785,11 +786,7 @@ public sealed class WebGameHost
                 _adventureTranslations.TryGetValue(themeName, out translationContent);
             }
 
-            // Create a web-compatible renderer adapter for AdventureEngine
-            var rendererAdapter = new WebRendererAdapter(this);
-            var adventureEngine = new AdventureEngine(rendererAdapter, _loc);
-            var events = await adventureEngine.PlayAdventureFromContent(
-                theme, _state, scriptContent, translationContent);
+            var events = await PlayAdventureWasmAsync(theme, scriptContent, translationContent);
 
             foreach (var evt in events)
             {
@@ -826,6 +823,195 @@ public sealed class WebGameHost
         await WaitForKeyAsync();
     }
 
+    /// <summary>
+    /// WASM-compatible adventure playback. Uses a queue-based pattern to bridge
+    /// Loreline's synchronous callbacks with async terminal I/O.
+    /// Loreline handlers store their continuation and signal the async loop,
+    /// which processes the action (render, wait for input) then resumes Loreline.
+    /// </summary>
+    private async Task<List<AdventureEvent>> PlayAdventureWasmAsync(
+        AdventureTheme theme, string scriptContent, string? translationContent)
+    {
+        var events = new List<AdventureEvent>();
+        string themeName = theme.ToString().ToLowerInvariant();
+        string adventureId = $"{themeName}/intro";
+
+        // Parse script
+        var script = Loreline.Engine.Parse(
+            scriptContent,
+            $"{themeName}/intro.lor",
+            (path, callback) => callback(string.Empty));
+
+        if (script is null)
+        {
+            await ShowErrorAsync("Failed to parse adventure script.");
+            return events;
+        }
+
+        // Build interpreter options
+        var options = Loreline.Interpreter.InterpreterOptions.Default();
+
+        // Build custom functions using AdventureEngine's public method.
+        // We use a dummy renderer that does nothing for ShowMessage calls inside custom functions
+        // (events are tracked in the events list and displayed elsewhere).
+        var dummyRenderer = new NoOpRenderer();
+        var engineHelper = new AdventureEngine(dummyRenderer, _loc);
+        options.Functions = engineHelper.BuildCustomFunctions(_state, events);
+
+        if (translationContent is not null)
+        {
+            var translationScript = Loreline.Engine.Parse(translationContent);
+            if (translationScript is not null)
+                options.Translations = Loreline.Engine.ExtractTranslations(translationScript);
+        }
+
+        // Queue-based async bridge for Loreline callbacks
+        // Each handler stores its data + continuation, then signals the loop
+        Action? pendingContinuation = null;
+        string? pendingDialogueChar = null;
+        string? pendingDialogueText = null;
+        List<string>? pendingChoiceOptions = null;
+        List<bool>? pendingChoiceEnabled = null;
+        List<string?>? pendingChoiceHints = null;
+        Action<int>? pendingChoiceCallback = null;
+        bool finished = false;
+        var actionReady = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);
+
+        // Dialogue handler: store callback, DON'T call it — let the async loop handle it
+        void HandleDialogue(Loreline.Interpreter.Dialogue dialogue)
+        {
+            string? displayName = dialogue.Character;
+            if (displayName is not null)
+            {
+                string characterName = dialogue.Interpreter.GetCharacterField(displayName, "name") as string
+                                       ?? displayName;
+                string key = $"character.{characterName.ToLowerInvariant().Replace(" ", "_").Replace("'", "")}";
+                string localized = _loc.Get(key);
+                displayName = !localized.StartsWith("[MISSING:") ? localized : characterName;
+            }
+
+            pendingDialogueChar = displayName;
+            pendingDialogueText = dialogue.Text;
+            pendingContinuation = () => dialogue.Callback();
+            actionReady.TrySetResult();
+        }
+
+        // Choice handler: store options + callback, DON'T call it
+        void HandleChoice(Loreline.Interpreter.Choice choice)
+        {
+            var opts = new List<string>();
+            var enabled = new List<bool>();
+            var hints = new List<string?>();
+
+            foreach (var opt in choice.Options)
+            {
+                var (text, hint) = HintSeparator.Parse(opt.Text);
+                if (opt.Enabled)
+                {
+                    opts.Add(text);
+                    enabled.Add(true);
+                    hints.Add(null);
+                }
+                else
+                {
+                    string prefix = hint ?? _loc.Get("adventure.unavailable");
+                    opts.Add($"({prefix}) {text}");
+                    enabled.Add(false);
+                    hints.Add(hint);
+                }
+            }
+
+            pendingChoiceOptions = opts;
+            pendingChoiceEnabled = enabled;
+            pendingChoiceHints = hints;
+            pendingChoiceCallback = idx => choice.Callback(idx);
+            pendingContinuation = null; // signal that this is a choice, not a dialogue
+            actionReady.TrySetResult();
+        }
+
+        void HandleFinish(Loreline.Interpreter.Finish _)
+        {
+            finished = true;
+            actionReady.TrySetResult();
+        }
+
+        // Check for saved progress
+        bool hasSave = _state.AdventureSaveData.TryGetValue(adventureId, out string? saveData)
+                       && !string.IsNullOrEmpty(saveData);
+
+        Loreline.Interpreter interpreter;
+        if (hasSave)
+        {
+            interpreter = Loreline.Engine.Resume(
+                script, HandleDialogue, HandleChoice, HandleFinish,
+                saveData!, options: options);
+        }
+        else
+        {
+            interpreter = Loreline.Engine.Play(
+                script, HandleDialogue, HandleChoice, HandleFinish,
+                options: options);
+        }
+
+        // Async loop: process queued actions until the adventure finishes
+        while (!finished)
+        {
+            await actionReady.Task;
+            actionReady = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);
+
+            if (finished) break;
+
+            if (pendingChoiceCallback is not null)
+            {
+                // Choice action: show options, get selection, resume Loreline
+                var choiceOpts = pendingChoiceOptions!;
+                var choiceEnabled = pendingChoiceEnabled!;
+                var choiceHints = pendingChoiceHints!;
+                var choiceCb = pendingChoiceCallback;
+                pendingChoiceCallback = null;
+                pendingChoiceOptions = null;
+                pendingChoiceEnabled = null;
+                pendingChoiceHints = null;
+
+                int selectedIndex;
+                while (true)
+                {
+                    selectedIndex = await _terminal.ShowSelectionAsync(
+                        "", choiceOpts, _renderContext.HasArrowSelection);
+
+                    if (choiceEnabled[selectedIndex])
+                        break;
+
+                    if (choiceHints[selectedIndex] is { } hintText)
+                        await _terminal.WriteMarkupLineAsync($"[dim italic]{Spectre.Console.Markup.Escape(hintText)}[/]");
+
+                    await ShowErrorAsync(_loc.Get("adventure.unavailable"));
+                }
+
+                choiceCb(selectedIndex);
+            }
+            else if (pendingContinuation is not null)
+            {
+                // Dialogue action: show text, wait for key, resume Loreline
+                await ShowAdventureDialogueAsync(pendingDialogueChar, pendingDialogueText!);
+                await WaitForKeyAsync();
+
+                var cont = pendingContinuation;
+                pendingContinuation = null;
+                pendingDialogueChar = null;
+                pendingDialogueText = null;
+
+                cont();
+            }
+        }
+
+        // Adventure completed
+        _state.AdventureSaveData.Remove(adventureId);
+        _state.CompletedAdventures.Add(theme.ToString());
+
+        return events;
+    }
+
     // ── Appearance ───────────────────────────────────────────────────────
 
     private async Task ChangeAppearance()
@@ -1291,11 +1477,31 @@ public sealed class WebGameHost
 
 /// <summary>
 /// Adapter that implements IRenderer by delegating to WebGameHost's async methods.
-/// Used by AdventureEngine which requires a synchronous IRenderer.
-/// The adventure callbacks (HandleDialogue/HandleChoice) are called synchronously
-/// by Loreline, so this adapter blocks on the async methods.
-/// In WASM single-threaded mode, this works because Loreline callbacks
-/// resume execution synchronously via TaskCompletionSource.
+/// No-op renderer used only to satisfy AdventureEngine.BuildCustomFunctions() parameter.
+/// Custom function messages (e.g. "You received X") are not shown in WASM — the adventure
+/// dialogue provides the narrative, and events are tracked in the events list.
+/// </summary>
+internal sealed class NoOpRenderer : IRenderer
+{
+    public void ShowMessage(string message) { }
+    public void ShowError(string message) { }
+    public void ShowBoxOpening(string boxName, string rarity) { }
+    public void ShowLootReveal(List<(string name, string rarity, string category)> items) { }
+    public void ShowGameState(GameState state, RenderContext context) { }
+    public void ShowUIFeatureUnlocked(string featureName) { }
+    public void ShowAdventureDialogue(string? character, string text) { }
+    public int ShowAdventureChoice(List<string> options) => 0;
+    public void ShowAdventureHint(string hint) { }
+    public void ShowInteraction(string description) { }
+    public void WaitForKeyPress(string? message = null) { }
+    public void Clear() { }
+    public int ShowSelection(string prompt, List<string> options) => 0;
+    public string ShowTextInput(string prompt) => "";
+}
+
+/// <summary>
+/// [DEPRECATED] Sync→async bridge for IRenderer. Kept for reference but no longer used
+/// by adventure playback (which now uses PlayAdventureWasmAsync directly).
 /// </summary>
 internal sealed class WebRendererAdapter : IRenderer
 {

src/OpenTheBox.Web/WebTerminal.cs

@@ -14,11 +14,17 @@ public sealed class WebTerminal
     private static WebTerminal? _instance;
 
     private readonly IJSRuntime _js;
+
+    /// <summary>
+    /// Bounded key buffer — prevents held keys from accumulating minutes of input.
+    /// FullMode.DropWrite silently drops new keys when the buffer is full.
+    /// </summary>
     private readonly Channel<ConsoleKeyInfo> _keyChannel =
-        Channel.CreateUnbounded<ConsoleKeyInfo>(new UnboundedChannelOptions
+        Channel.CreateBounded<ConsoleKeyInfo>(new BoundedChannelOptions(8)
         {
             SingleReader = true,
-            SingleWriter = true
+            SingleWriter = true,
+            FullMode = BoundedChannelFullMode.DropOldest
         });
 
     public const int Width = 120;
@@ -77,6 +83,7 @@ public sealed class WebTerminal
             ColorSystem = ColorSystemSupport.TrueColor
         });
         console.Profile.Width = Width;
+        console.Profile.Height = Height;
         console.Write(renderable);
         return writer.ToString();
     }
@@ -105,6 +112,7 @@ public sealed class WebTerminal
             ColorSystem = ColorSystemSupport.TrueColor
         });
         console.Profile.Width = Width;
+        console.Profile.Height = Height;
         console.MarkupLine(markup);
         string ansi = writer.ToString().Replace("\n", "\r\n");
         await WriteAsync(ansi);
@@ -233,6 +241,7 @@ public sealed class WebTerminal
                 ColorSystem = ColorSystemSupport.TrueColor
             });
             console.Profile.Width = Width;
+            console.Profile.Height = Height;
 
             if (prompt.Length > 0)
                 console.MarkupLine($"[bold]{Markup.Escape(prompt)}[/]");
@@ -253,7 +262,8 @@ public sealed class WebTerminal
                 console.MarkupLine("[dim]  ▼ ...[/]");
 
             string rendered = writer.ToString().Replace("\n", "\r\n");
-            int lineCount = rendered.Split('\n').Length;
+            // Count actual line breaks — Split('\n').Length overcounts by 1 due to trailing newline
+            int lineCount = rendered.Count(c => c == '\n');
 
             await WriteAsync(rendered);
 

src/OpenTheBox.Web/wwwroot/appsettings.json

@@ -0,0 +1 @@
+{}

src/OpenTheBox.Web/wwwroot/js/terminal-interop.js

@@ -25,7 +25,12 @@ window.terminalInterop = {
         term.loadAddon(fitAddon);
 
         term.open(document.getElementById('terminal'));
+
+        // Fit to container, but enforce minimum dimensions for game readability
         fitAddon.fit();
+        if (term.cols < 120 || term.rows < 30) {
+            term.resize(Math.max(term.cols, 120), Math.max(term.rows, 30));
+        }
 
         // Forward key input to C#
         term.onData(function (data) {
@@ -35,6 +40,9 @@ window.terminalInterop = {
         // Handle resize
         window.addEventListener('resize', function () {
             fitAddon.fit();
+            if (term.cols < 120 || term.rows < 30) {
+                term.resize(Math.max(term.cols, 120), Math.max(term.rows, 30));
+            }
         });
 
         this.term = term;

src/OpenTheBox/Adventures/AdventureEngine.cs

@@ -30,7 +30,7 @@ public enum GameEventKind
 /// <example>
 /// In .lor files: Open the secret path|||A keen sense of Luck might help here... #label [if hasStat("Luck", 30)]
 /// </example>
-internal static class HintSeparator
+public static class HintSeparator
 {
     public const string Delimiter = "|||";
 
@@ -77,6 +77,13 @@ public sealed class AdventureEngine
     /// </summary>
     public async Task<List<AdventureEvent>> PlayAdventure(AdventureTheme theme, GameState state)
     {
+        // In WASM, use PlayAdventureFromContent() with pre-loaded scripts instead
+        if (OperatingSystem.IsBrowser())
+        {
+            _renderer.ShowError("PlayAdventure requires file I/O. Use PlayAdventureFromContent in WASM.");
+            return [];
+        }
+
         string themeName = theme.ToString().ToLowerInvariant();
         string scriptPath = Path.Combine(AdventuresRoot, themeName, "intro.lor");
 
@@ -338,7 +345,11 @@ public sealed class AdventureEngine
 
     // ── Custom functions registered into the Loreline interpreter ────────
 
-    private Dictionary<string, Loreline.Interpreter.Function> BuildCustomFunctions(
+    /// <summary>
+    /// Builds the custom Loreline functions dictionary for a given game state.
+    /// Public so the WASM build can reuse it with its own async adventure loop.
+    /// </summary>
+    public Dictionary<string, Loreline.Interpreter.Function> BuildCustomFunctions(
         GameState state,
         List<AdventureEvent> events)
     {

src/OpenTheBox/Data/ContentRegistry.cs

@@ -42,6 +42,10 @@ public class ContentRegistry
     public static ContentRegistry LoadFromFiles(
         string itemsPath, string boxesPath, string interactionsPath, string? recipesPath = null)
     {
+        if (OperatingSystem.IsBrowser())
+            throw new PlatformNotSupportedException(
+                "LoadFromFiles requires file I/O. Use LoadFromStrings in WASM.");
+
         var registry = new ContentRegistry();
 
         if (File.Exists(itemsPath))

src/OpenTheBox/Localization/LocalizationManager.cs

@@ -35,6 +35,10 @@ public sealed class LocalizationManager
         CurrentLocale = locale;
         _strings = [];
 
+        // File I/O is not available in Blazor WASM — use LoadFromString() instead
+        if (OperatingSystem.IsBrowser())
+            return;
+
         string localeName = locale.ToString().ToLowerInvariant();
         string path = Path.Combine(StringsDirectory, $"{localeName}.json");
 

tests/OpenTheBox.Web.Tests/GameFlowTests.cs

@@ -0,0 +1,393 @@
+using Microsoft.Playwright;
+
+namespace OpenTheBox.Web.Tests;
+
+/// <summary>
+/// End-to-end tests that validate the web game is interactive and functional.
+/// These tests launch the Blazor WASM app and interact with the xterm.js terminal.
+/// </summary>
+[Collection("WebApp")]
+public class GameFlowTests
+{
+    private readonly WebAppFixture _fixture;
+
+    public GameFlowTests(WebAppFixture fixture)
+    {
+        _fixture = fixture;
+    }
+
+    private async Task<(IPage page, IBrowserContext context)> CreateFreshSessionAsync()
+    {
+        var context = await _fixture.Browser.NewContextAsync(new BrowserNewContextOptions
+        {
+            ViewportSize = new ViewportSize { Width = 1400, Height = 900 }
+        });
+        var page = await context.NewPageAsync();
+        return (page, context);
+    }
+
+    /// <summary>
+    /// Types a number and presses Enter for numbered selection prompts.
+    /// </summary>
+    private static async Task SelectNumberedOptionAsync(IPage page, int number)
+    {
+        await TerminalHelper.PressDigitAsync(page, number);
+        await Task.Delay(200);
+        await TerminalHelper.PressEnterAsync(page);
+    }
+
+    /// <summary>
+    /// Navigates through language selection → main menu → name entry → game loop.
+    /// Returns the page ready at the first action menu.
+    /// </summary>
+    private async Task<IPage> StartNewGameAsync(IBrowserContext context, string playerName = "Tester")
+    {
+        var page = await context.NewPageAsync();
+        await page.GotoAsync(_fixture.BaseUrl, new PageGotoOptions { WaitUntil = WaitUntilState.NetworkIdle });
+        await TerminalHelper.WaitForTerminalReadyAsync(page, timeoutMs: 90000);
+
+        // Language selection → English
+        await TerminalHelper.WaitForTerminalTextAsync(page, "Language", timeoutMs: 60000);
+        await SelectNumberedOptionAsync(page, 1);
+        await Task.Delay(500);
+
+        // Main menu → New Game
+        await TerminalHelper.WaitForTerminalTextAsync(page, "OPEN THE BOX", timeoutMs: 30000);
+        await SelectNumberedOptionAsync(page, 1);
+        await Task.Delay(500);
+
+        // Name prompt
+        await TerminalHelper.WaitForTerminalTextAsync(page, "name", timeoutMs: 15000);
+        await TerminalHelper.TypeAsync(page, playerName);
+        await TerminalHelper.PressEnterAsync(page);
+        await Task.Delay(500);
+
+        // Welcome message → press Enter
+        await TerminalHelper.WaitForTerminalTextAsync(page, playerName, timeoutMs: 10000);
+        await TerminalHelper.PressEnterAsync(page);
+        await Task.Delay(500);
+
+        // Wait for action menu
+        await TerminalHelper.WaitForTerminalTextAsync(page, "Open a box", timeoutMs: 15000);
+
+        return page;
+    }
+
+    /// <summary>
+    /// Opens a box from the action menu (selects "Open a box" → selects box #1 → presses through results).
+    /// </summary>
+    private static async Task OpenBoxAsync(IPage page)
+    {
+        // Select "Open a box" — find which option number it is
+        var content = await TerminalHelper.ReadTerminalAsync(page);
+
+        // "Open a box" should be option 1 in the action menu
+        await SelectNumberedOptionAsync(page, 1);
+        await Task.Delay(500);
+
+        // Select the first box in the list
+        await SelectNumberedOptionAsync(page, 1);
+        await Task.Delay(1000);
+
+        // Press Enter through box opening results
+        for (int i = 0; i < 3; i++)
+        {
+            await TerminalHelper.PressEnterAsync(page);
+            await Task.Delay(300);
+        }
+
+        // Wait for the action menu to reappear
+        await TerminalHelper.WaitForTerminalTextAsync(page, "Open a box", timeoutMs: 15000);
+    }
+
+    // ── Tests ──────────────────────────────────────────────────────────────
+
+    [Fact]
+    public async Task PageLoads_TerminalInitializes()
+    {
+        var (page, context) = await CreateFreshSessionAsync();
+        var consoleLogs = new List<string>();
+        page.Console += (_, msg) => consoleLogs.Add($"[{msg.Type}] {msg.Text}");
+        page.PageError += (_, error) => consoleLogs.Add($"[PAGE ERROR] {error}");
+        try
+        {
+            await page.GotoAsync(_fixture.BaseUrl, new PageGotoOptions { WaitUntil = WaitUntilState.NetworkIdle });
+            await TerminalHelper.WaitForTerminalReadyAsync(page, timeoutMs: 90000);
+
+            var containerVisible = await page.EvaluateAsync<bool>(@"() => {
+                const el = document.getElementById('terminal-container');
+                return el && el.classList.contains('active');
+            }");
+            Assert.True(containerVisible, "Terminal container should be active");
+
+            var loadingHidden = await page.EvaluateAsync<bool>(@"() => {
+                const el = document.getElementById('loading');
+                return el && el.classList.contains('hidden');
+            }");
+            Assert.True(loadingHidden, "Loading screen should be hidden");
+
+            var cols = await page.EvaluateAsync<int>("() => window.terminalInterop?.term?.cols ?? 0");
+            Assert.True(cols >= 120, $"Terminal should have at least 120 cols, got {cols}");
+
+            Assert.DoesNotContain(consoleLogs, l => l.StartsWith("[error]"));
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+
+    [Fact]
+    public async Task LanguageSelection_DisplaysOptions()
+    {
+        var (page, context) = await CreateFreshSessionAsync();
+        try
+        {
+            await page.GotoAsync(_fixture.BaseUrl, new PageGotoOptions { WaitUntil = WaitUntilState.NetworkIdle });
+            await TerminalHelper.WaitForTerminalReadyAsync(page, timeoutMs: 90000);
+
+            await TerminalHelper.WaitForTerminalTextAsync(page, "Language", timeoutMs: 60000);
+
+            var content = await TerminalHelper.ReadTerminalAsync(page);
+            Assert.Contains("English", content);
+            Assert.Contains("Fran", content);
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+
+    [Fact]
+    public async Task FullFlow_SelectLanguage_EnterName_OpenFirstBox()
+    {
+        var (_, context) = await CreateFreshSessionAsync();
+        try
+        {
+            var page = await StartNewGameAsync(context);
+
+            // Verify initial state
+            var content = await TerminalHelper.ReadTerminalAsync(page);
+            Console.WriteLine($"Initial game state:\n{content}");
+            Assert.Contains("Boxes Opened: 0", content);
+
+            // Open the first box
+            await OpenBoxAsync(page);
+
+            // Verify box was opened
+            var afterOpen = await TerminalHelper.ReadTerminalAsync(page);
+            Console.WriteLine($"After first box:\n{afterOpen}");
+            Assert.Contains("Boxes Opened: 1", afterOpen);
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+
+    [Fact]
+    public async Task MultipleBoxes_ProgressionAndMetaUnlocks()
+    {
+        var (_, context) = await CreateFreshSessionAsync();
+        var consoleLogs = new List<string>();
+        try
+        {
+            var page = await StartNewGameAsync(context);
+            page.Console += (_, msg) => consoleLogs.Add($"[{msg.Type}] {msg.Text}");
+
+            // Open several boxes — should trigger meta unlocks (new UI features)
+            // The pacing test says 1st meta UI unlock should happen before box ~50
+            int boxesOpened = 0;
+            bool sawNewLabel = false;
+            bool sawAdventure = false;
+
+            for (int i = 0; i < 20; i++)
+            {
+                await OpenBoxAsync(page);
+                boxesOpened++;
+
+                var content = await TerminalHelper.ReadTerminalAsync(page);
+
+                // Check for NEW labels (meta unlocks) or adventure option
+                if (content.Contains("NEW", StringComparison.Ordinal))
+                    sawNewLabel = true;
+                if (content.Contains("adventure", StringComparison.OrdinalIgnoreCase))
+                    sawAdventure = true;
+
+                Console.WriteLine($"Box #{boxesOpened}: menu options visible. NEW={sawNewLabel}, Adventure={sawAdventure}");
+
+                // If we've seen both, no need to open more
+                if (sawNewLabel && sawAdventure)
+                    break;
+            }
+
+            Console.WriteLine($"After {boxesOpened} boxes: NEW labels seen={sawNewLabel}, Adventure unlocked={sawAdventure}");
+
+            // Verify no browser errors from box opening
+            var errors = consoleLogs.Where(l => l.StartsWith("[error]")).ToList();
+            foreach (var err in errors)
+                Console.WriteLine($"Browser error: {err}");
+            Assert.Empty(errors);
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+
+    [Fact]
+    public async Task ExtendedPlay_NoWasmCrash()
+    {
+        var (_, context) = await CreateFreshSessionAsync();
+        var consoleLogs = new List<string>();
+        try
+        {
+            var page = await StartNewGameAsync(context);
+            page.Console += (_, msg) => consoleLogs.Add($"[{msg.Type}] {msg.Text}");
+
+            // Open 20+ boxes — should trigger meta unlocks, arrow navigation, adventures
+            // This validates that the full game loop works in WASM without crashing
+            for (int i = 0; i < 25; i++)
+            {
+                await OpenBoxAsync(page);
+
+                // Check for fatal errors after each box
+                bool hasFatalError = consoleLogs.Any(l => l.Contains("[OpenTheBox] Fatal error"));
+                if (hasFatalError)
+                {
+                    var errors = consoleLogs.Where(l => l.Contains("error", StringComparison.OrdinalIgnoreCase));
+                    foreach (var err in errors)
+                        Console.WriteLine($"WASM error: {err}");
+                    Assert.Fail($"Fatal error after box #{i + 1}");
+                }
+            }
+
+            var finalContent = await TerminalHelper.ReadTerminalAsync(page);
+            Console.WriteLine($"After 25 boxes:\n{finalContent}");
+
+            // After 25 boxes, the game should still be running and show the action menu
+            Assert.Contains("box", finalContent, StringComparison.OrdinalIgnoreCase);
+
+            // Verify no WASM-specific errors
+            bool hasMonitorError = consoleLogs.Any(l => l.Contains("Cannot wait on monitors"));
+            Assert.False(hasMonitorError, "Should not get 'Cannot wait on monitors' error in WASM");
+
+            bool hasPlatformError = consoleLogs.Any(l => l.Contains("PlatformNotSupported"));
+            Assert.False(hasPlatformError, "Should not get PlatformNotSupportedException in WASM");
+
+            Console.WriteLine($"25 boxes opened successfully. Browser console had {consoleLogs.Count} messages.");
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+
+    [Fact]
+    public async Task Adventure_NoWasmCrash()
+    {
+        var (_, context) = await CreateFreshSessionAsync();
+        var consoleLogs = new List<string>();
+        try
+        {
+            var page = await StartNewGameAsync(context);
+            page.Console += (_, msg) => consoleLogs.Add($"[{msg.Type}] {msg.Text}");
+
+            // Open boxes until adventure is unlocked
+            bool adventureUnlocked = false;
+            for (int i = 0; i < 30 && !adventureUnlocked; i++)
+            {
+                await OpenBoxAsync(page);
+                var content = await TerminalHelper.ReadTerminalAsync(page);
+                adventureUnlocked = content.Contains("adventure", StringComparison.OrdinalIgnoreCase);
+            }
+
+            if (!adventureUnlocked)
+            {
+                Console.WriteLine("Adventure not unlocked within 30 boxes — skipping");
+                return;
+            }
+
+            Console.WriteLine("Adventure unlocked, attempting to start...");
+
+            // Navigate to adventure: use arrow keys to find "adventure" option
+            // Try each digit from 1-9 — the arrow selection responds to digit shortcuts
+            for (int d = 1; d <= 9; d++)
+            {
+                await TerminalHelper.PressDigitAsync(page, d);
+                await Task.Delay(1000);
+
+                var content = await TerminalHelper.ReadTerminalAsync(page);
+                // If we see the adventure list (contains "Back" and a theme name), we found it
+                if (content.Contains("Back", StringComparison.OrdinalIgnoreCase)
+                    && !content.Contains("Open a box", StringComparison.OrdinalIgnoreCase))
+                {
+                    Console.WriteLine($"Adventure menu found with digit {d}");
+                    break;
+                }
+
+                // If we accidentally selected something else, press Escape or go back
+                if (!content.Contains("adventure", StringComparison.OrdinalIgnoreCase))
+                {
+                    // We're in a submenu we don't want — go back by selecting "Back" option
+                    // First check if this is a box selection or other menu
+                    if (content.Contains("Back"))
+                    {
+                        // Find the Back option number and press it
+                        var backLines = content.Split('\n');
+                        foreach (var line in backLines)
+                        {
+                            if (line.Contains("Back"))
+                            {
+                                foreach (var ch in line)
+                                {
+                                    if (char.IsDigit(ch))
+                                    {
+                                        await TerminalHelper.PressDigitAsync(page, ch - '0');
+                                        await Task.Delay(500);
+                                        break;
+                                    }
+                                }
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+
+            // Try to select the first adventure
+            await TerminalHelper.PressDigitAsync(page, 1);
+            await Task.Delay(2000);
+
+            // Read the result
+            var dialogueContent = await TerminalHelper.ReadTerminalAsync(page);
+            Console.WriteLine($"After adventure selection:\n{dialogueContent}");
+
+            // The key assertion: no WASM-specific crash errors
+            bool hasMonitorError = consoleLogs.Any(l => l.Contains("Cannot wait on monitors"));
+            Assert.False(hasMonitorError, "Should not get 'Cannot wait on monitors' error in WASM");
+
+            bool hasFatalError = consoleLogs.Any(l => l.Contains("[OpenTheBox] Fatal error"));
+            if (hasFatalError)
+            {
+                var errors = consoleLogs.Where(l => l.Contains("error", StringComparison.OrdinalIgnoreCase));
+                foreach (var err in errors)
+                    Console.WriteLine($"Browser error: {err}");
+            }
+            Assert.False(hasFatalError, "Should not get fatal error during adventure");
+
+            // If we got this far with dialogue, press through a few lines
+            for (int i = 0; i < 5; i++)
+            {
+                await TerminalHelper.PressEnterAsync(page);
+                await Task.Delay(500);
+            }
+
+            Console.WriteLine("Adventure test completed without WASM crash");
+        }
+        finally
+        {
+            await context.CloseAsync();
+        }
+    }
+}

tests/OpenTheBox.Web.Tests/OpenTheBox.Web.Tests.csproj

@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
+    <PackageReference Include="Microsoft.Playwright" Version="1.52.0" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.4" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="Xunit" />
+  </ItemGroup>
+
+</Project>

tests/OpenTheBox.Web.Tests/TerminalHelper.cs

@@ -0,0 +1,107 @@
+using Microsoft.Playwright;
+
+namespace OpenTheBox.Web.Tests;
+
+/// <summary>
+/// Helpers for interacting with the xterm.js terminal in Playwright tests.
+/// </summary>
+public static class TerminalHelper
+{
+    /// <summary>
+    /// Reads the visible text content from the xterm.js terminal buffer.
+    /// </summary>
+    public static async Task<string> ReadTerminalAsync(IPage page)
+    {
+        return await page.EvaluateAsync<string>(@"() => {
+            const term = window.terminalInterop?.term;
+            if (!term) return '';
+            const buffer = term.buffer.active;
+            let text = '';
+            for (let i = 0; i < buffer.length; i++) {
+                const line = buffer.getLine(i);
+                if (line) text += line.translateToString(true) + '\n';
+            }
+            return text;
+        }");
+    }
+
+    /// <summary>
+    /// Waits until the terminal contains the specified text, with timeout.
+    /// </summary>
+    public static async Task WaitForTerminalTextAsync(IPage page, string text, int timeoutMs = 30000)
+    {
+        var deadline = DateTime.UtcNow.AddMilliseconds(timeoutMs);
+        while (DateTime.UtcNow < deadline)
+        {
+            var content = await ReadTerminalAsync(page);
+            if (content.Contains(text, StringComparison.OrdinalIgnoreCase))
+                return;
+            await Task.Delay(500);
+        }
+        // Read one final time for the error message
+        var finalContent = await ReadTerminalAsync(page);
+        throw new TimeoutException(
+            $"Terminal did not contain \"{text}\" within {timeoutMs}ms.\n" +
+            $"Terminal content:\n{finalContent}");
+    }
+
+    /// <summary>
+    /// Types text into the terminal (sends keystrokes).
+    /// </summary>
+    public static async Task TypeAsync(IPage page, string text)
+    {
+        await page.Keyboard.TypeAsync(text, new KeyboardTypeOptions { Delay = 50 });
+    }
+
+    /// <summary>
+    /// Presses Enter in the terminal.
+    /// </summary>
+    public static async Task PressEnterAsync(IPage page)
+    {
+        await page.Keyboard.PressAsync("Enter");
+    }
+
+    /// <summary>
+    /// Presses a specific key (Arrow keys, Escape, etc.).
+    /// </summary>
+    public static async Task PressKeyAsync(IPage page, string key)
+    {
+        await page.Keyboard.PressAsync(key);
+    }
+
+    /// <summary>
+    /// Sends a digit key press (1-9) for numbered menu selection.
+    /// </summary>
+    public static async Task PressDigitAsync(IPage page, int digit)
+    {
+        await page.Keyboard.PressAsync($"Digit{digit}");
+    }
+
+    /// <summary>
+    /// Waits for the terminal to be initialized (xterm.js loaded and terminal visible).
+    /// </summary>
+    public static async Task WaitForTerminalReadyAsync(IPage page, int timeoutMs = 60000)
+    {
+        var deadline = DateTime.UtcNow.AddMilliseconds(timeoutMs);
+        while (DateTime.UtcNow < deadline)
+        {
+            var ready = await page.EvaluateAsync<bool>(@"() => {
+                return window.terminalInterop?.term != null;
+            }");
+            if (ready)
+            {
+                // Verify terminal has proper dimensions (should be 120x30 after init)
+                var cols = await page.EvaluateAsync<int>("() => window.terminalInterop.term.cols");
+                if (cols < 120)
+                {
+                    // Force resize if fit addon miscalculated (e.g., headless browser)
+                    await page.EvaluateAsync("() => window.terminalInterop.term.resize(120, 30)");
+                    await Task.Delay(200);
+                }
+                return;
+            }
+            await Task.Delay(500);
+        }
+        throw new TimeoutException($"Terminal was not initialized within {timeoutMs}ms");
+    }
+}

tests/OpenTheBox.Web.Tests/WebAppFixture.cs

@@ -0,0 +1,82 @@
+using System.Diagnostics;
+using Microsoft.Playwright;
+
+namespace OpenTheBox.Web.Tests;
+
+/// <summary>
+/// Shared fixture that starts the Blazor WASM dev server and Playwright browser once per test collection.
+/// </summary>
+public class WebAppFixture : IAsyncLifetime
+{
+    private Process? _serverProcess;
+    public IBrowser Browser { get; private set; } = null!;
+    public IPlaywright Playwright { get; private set; } = null!;
+    public string BaseUrl { get; private set; } = "http://localhost:5280";
+
+    public async Task InitializeAsync()
+    {
+        // Start the Blazor WASM dev server
+        _serverProcess = new Process
+        {
+            StartInfo = new ProcessStartInfo
+            {
+                FileName = "dotnet",
+                Arguments = $"run --project src/OpenTheBox.Web --urls {BaseUrl}",
+                WorkingDirectory = FindSolutionRoot(),
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
+                UseShellExecute = false,
+                CreateNoWindow = true
+            }
+        };
+        _serverProcess.Start();
+
+        // Wait for the server to be ready (try connecting)
+        using var httpClient = new HttpClient();
+        for (int i = 0; i < 120; i++) // up to 2 minutes for WASM compilation
+        {
+            try
+            {
+                var response = await httpClient.GetAsync(BaseUrl);
+                if (response.IsSuccessStatusCode) break;
+            }
+            catch { }
+            await Task.Delay(1000);
+        }
+
+        // Initialize Playwright
+        Playwright = await Microsoft.Playwright.Playwright.CreateAsync();
+        Browser = await Playwright.Chromium.LaunchAsync(new BrowserTypeLaunchOptions
+        {
+            Headless = true,
+            Args = ["--window-size=1400,900"]
+        });
+    }
+
+    public async Task DisposeAsync()
+    {
+        await Browser.DisposeAsync();
+        Playwright.Dispose();
+
+        if (_serverProcess is { HasExited: false })
+        {
+            _serverProcess.Kill(entireProcessTree: true);
+            _serverProcess.Dispose();
+        }
+    }
+
+    private static string FindSolutionRoot()
+    {
+        var dir = new DirectoryInfo(AppContext.BaseDirectory);
+        while (dir != null)
+        {
+            if (dir.GetFiles("OpenTheBox.slnx").Length > 0)
+                return dir.FullName;
+            dir = dir.Parent;
+        }
+        throw new InvalidOperationException("Could not find solution root (OpenTheBox.slnx)");
+    }
+}
+
+[CollectionDefinition("WebApp")]
+public class WebAppCollection : ICollectionFixture<WebAppFixture>;

tests/snapshots/item_utility_report.txt

@@ -1,5 +1,5 @@
 # Item Utility Report
-# Total items: 152
+# Total items: 151
 # Total boxes: 31
 # Total recipes: 18
 
@@ -439,7 +439,7 @@
       Adventure: Pirate
       Interaction: pirate_map_compass
 
-## Material (15 items)
+## Material (14 items)
 ────────────────────────────────────────────────────────────────────────────────
   [****] material_bronze_ingot (Uncommon) — Bronze
       Loot: box_ok_tier
@@ -502,8 +502,6 @@
   [*] material_diamond_gem (Legendary) — Diamant
       Loot: box_black
 
-  [NO USE] material_wood_nail (Common) — Bois
-
 ## Meta (33 items)
 ────────────────────────────────────────────────────────────────────────────────
   [**] meta_colors (Rare) — Couleurs de texte
@@ -675,4 +673,4 @@
 
 ## Orphan Items (no usage context)
 ────────────────────────────────────────────────────────────────────────────────
-  material_wood_nail (Material, Common)
+  (none)