feat: Refactor Wolf3dApp to manage audio shutdown on dispose and add audio shutdown test

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

packages/wolf_3d_flutter/lib/widgets/wolf3d_app.dart

@@ -1,8 +1,7 @@
 library;
 
-import 'dart:collection';
+import 'dart:async';
 
-import 'package:file_selector/file_selector.dart';
 import 'package:flutter/material.dart';
 import 'package:wolf_3d_flutter/wolf_3d_flutter.dart';
 
@@ -21,108 +20,38 @@ class Wolf3dApp extends StatefulWidget {
   State<Wolf3dApp> createState() => _Wolf3dAppState();
 }
 
-class _Wolf3dAppState extends State<Wolf3dApp> {
-  bool _isLoadingGameData = false;
-  String? _pickerError;
+class _Wolf3dAppState extends State<Wolf3dApp> with WidgetsBindingObserver {
+  Future<void>? _shutdownFuture;
 
-  Future<void> _pickGameDataDirectory() async {
-    setState(() {
-      _isLoadingGameData = true;
-      _pickerError = null;
-    });
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addObserver(this);
+  }
 
-    try {
-      final String? directoryPath = await getDirectoryPath(
-        confirmButtonText: 'Use this folder',
-      );
+  @override
+  void dispose() {
+    WidgetsBinding.instance.removeObserver(this);
+    unawaited(_ensureAudioShutdown());
+    super.dispose();
+  }
 
-      if (directoryPath == null || directoryPath.trim().isEmpty) {
-        return;
-      }
-
-      await widget.engine.init(directory: directoryPath.trim());
-    } catch (error) {
-      setState(() {
-        _pickerError = 'Unable to load selected directory: $error';
-      });
-    } finally {
-      if (mounted) {
-        setState(() {
-          _isLoadingGameData = false;
-        });
-      }
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    if (state == AppLifecycleState.detached) {
+      unawaited(_ensureAudioShutdown());
     }
   }
 
-  Future<void> _pickGameDataFiles() async {
-    setState(() {
-      _isLoadingGameData = true;
-      _pickerError = null;
-    });
-
-    try {
-      final List<XFile> selectedFiles = await openFiles();
-
-      if (selectedFiles.isEmpty) {
-        return;
-      }
-
-      final LinkedHashSet<String> directories = LinkedHashSet<String>();
-      for (final XFile file in selectedFiles) {
-        final String directory = _directoryFromFilePath(file.path);
-        if (directory.isNotEmpty) {
-          directories.add(directory);
-        }
-      }
-
-      if (directories.isEmpty) {
-        setState(() {
-          _pickerError = 'Selected files do not expose local filesystem paths.';
-        });
-        return;
-      }
-
-      final List<String> orderedDirectories = directories.toList(
-        growable: false,
-      );
-      await widget.engine.init(
-        directory: orderedDirectories.first,
-        additionalDirectories: orderedDirectories.skip(1),
-      );
-    } catch (error) {
-      setState(() {
-        _pickerError = 'Unable to load selected files: $error';
-      });
-    } finally {
-      if (mounted) {
-        setState(() {
-          _isLoadingGameData = false;
-        });
-      }
-    }
-  }
-
-  String _directoryFromFilePath(String path) {
-    final String trimmedPath = path.trim();
-    if (trimmedPath.isEmpty) {
-      return '';
+  Future<void> _ensureAudioShutdown() {
+    final Future<void>? existing = _shutdownFuture;
+    if (existing != null) {
+      return existing;
     }
 
-    final int slashIndex = trimmedPath.lastIndexOf('/');
-    final int backslashIndex = trimmedPath.lastIndexOf(r'\');
-    final int separatorIndex = slashIndex > backslashIndex
-        ? slashIndex
-        : backslashIndex;
-
-    if (separatorIndex < 0) {
-      return '';
-    }
-
-    if (separatorIndex == 0) {
-      return trimmedPath[0];
-    }
-
-    return trimmedPath.substring(0, separatorIndex);
+    final Future<void> shutdown = widget.engine.shutdownAudio();
+    _shutdownFuture = shutdown;
+    return shutdown;
   }
 
   @override
@@ -130,10 +59,6 @@ class _Wolf3dAppState extends State<Wolf3dApp> {
     return widget.engine.availableGames.isEmpty
         ? NoGameDataScreen(
             configuredDataDirectory: widget.engine.configuredDataDirectory,
-            onPickGameDataDirectory: _pickGameDataDirectory,
-            onPickGameDataFiles: _pickGameDataFiles,
-            isLoadingGameData: _isLoadingGameData,
-            pickerError: _pickerError,
           )
         : GameScreen(wolf3d: widget.engine);
   }