/// High-level Flutter facade for discovering game data and sharing runtime services.
library;

import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:wolf_3d_dart/wolf_3d_data.dart';
import 'package:wolf_3d_dart/wolf_3d_data_types.dart';
import 'package:wolf_3d_dart/wolf_3d_engine.dart';
import 'package:wolf_3d_flutter/audio/wolf3d_platform_audio.dart';
import 'package:wolf_3d_flutter/managers/desktop_windowing_support.dart'
    as desktop_windowing_support;
import 'package:wolf_3d_flutter/managers/game_data_directory_persistence.dart';
import 'package:wolf_3d_flutter/wolf_3d_input_flutter.dart';

export 'package:wolf_3d_dart/wolf_3d_audio.dart' show DebugMusicPlayer;

export 'audio/wolf3d_platform_audio.dart' show Wolf3dPlatformAudio;
export 'managers/game_app_lifecycle_manager.dart' show GameAppLifecycleManager;
export 'managers/game_data_directory_persistence.dart'
    show DefaultGameDataDirectoryPersistence;
export 'managers/game_display_manager.dart' show GameDisplayManager;
export 'managers/game_persistence_manager.dart' show GamePersistenceManager;
export 'managers/game_renderer_mode_manager.dart'
    show GameRendererMode, gameRendererModeFromSettings, handleGlslUnavailable;
export 'managers/game_screen_input_manager.dart'
    show
        HostShortcutBinding,
        HostShortcutHandler,
        HostShortcutIntent,
        HostShortcutRegistry,
        GameScreenInputManager,
        isAltEnterShortcut;
      export 'managers/wolf3d_app_manager.dart' show Wolf3dAppManager;
export 'screens/audio_gallery.dart' show AudioGallery;
export 'screens/debug_tools_screen.dart' show DebugToolsScreen;
export 'screens/game_screen.dart' show GameScreen;
export 'screens/no_game_data_screen.dart' show NoGameDataScreen;
export 'screens/sprite_gallery.dart' show SpriteGallery;
export 'screens/vga_gallery.dart' show VgaGallery;
export 'widgets/gallery_game_selector.dart'
    show GalleryGameSelector, formatGalleryGameTitle;
export 'widgets/wolf3d_app.dart' show Wolf3dApp;
export 'widgets/wolf_menu_shell.dart' show WolfMenuShell;

/// Flutter-specific host facade built on top of [Wolf3dEngine].
///
/// This type keeps platform-neutral session/engine state in the Dart package
/// while owning Flutter-only concerns such as bundle loading and discovery.
class Wolf3dFlutterEngine extends Wolf3dEngine {
  /// Creates an empty facade that must be initialized with [init].
  Wolf3dFlutterEngine({
    bool debug = false,
    EngineAudio? audioBackend,
    Wolf3dFlutterInput? inputBackend,
    DefaultGameDataDirectoryPersistence? dataDirectoryPersistence,
  }) : dataDirectoryPersistence =
           dataDirectoryPersistence ?? DefaultGameDataDirectoryPersistence(),
       super(
         audio: audioBackend ?? Wolf3dPlatformAudio(),
         input: inputBackend ?? Wolf3dFlutterInput(),
       ) {
    if (debug) {
      enableDebug();
    }
  }

  /// Persists and restores the preferred external game-data directory.
  final DefaultGameDataDirectoryPersistence dataDirectoryPersistence;

  /// Last configured/loaded external game-data directory path.
  String? configuredDataDirectory;

  /// Shared Flutter input adapter reused by gameplay screens.
  @override
  Wolf3dFlutterInput get input => super.input as Wolf3dFlutterInput;

  /// Enables host-level debug affordances such as debug navigation UI.
  @override
  Wolf3dFlutterEngine enableDebug() {
    super.enableDebug();
    return this;
  }

  /// Initializes the engine by loading available game data.
  Future<Wolf3dFlutterEngine> init({
    String? directory,
    Iterable<String>? additionalDirectories,
  }) async {
    await desktop_windowing_support.ensureDesktopWindowingInitialized();
    await audio.init();
    availableGames.clear();

    final String? requestedDirectory = directory?.trim();
    final String? resolvedDirectory =
        requestedDirectory != null && requestedDirectory.isNotEmpty
        ? requestedDirectory
        : await dataDirectoryPersistence.loadDataDirectory();
    configuredDataDirectory = resolvedDirectory;

    if (requestedDirectory != null && requestedDirectory.isNotEmpty) {
      await dataDirectoryPersistence.saveDataDirectory(requestedDirectory);
    }

    // Bundled assets let the GUI work out of the box on supported platforms.
    final versionsToTry = [
      (version: GameVersion.retail, path: 'retail'),
      (version: GameVersion.shareware, path: 'shareware'),
    ];

    for (final version in versionsToTry) {
      try {
        final ext = version.version.fileExtension;
        final folder = 'packages/wolf_3d_assets/assets/${version.path}';

        final data = WolfensteinLoader.loadFromBytes(
          version: version.version,
          vswap: await _tryLoad('$folder/VSWAP.$ext'),
          mapHead: await _tryLoad('$folder/MAPHEAD.$ext'),
          gameMaps: await _tryLoad('$folder/GAMEMAPS.$ext'),
          vgaDict: await _tryLoad('$folder/VGADICT.$ext'),
          vgaHead: await _tryLoad('$folder/VGAHEAD.$ext'),
          vgaGraph: await _tryLoad('$folder/VGAGRAPH.$ext'),
          audioHed: await _tryLoad('$folder/AUDIOHED.$ext'),
          audioT: await _tryLoad('$folder/AUDIOT.$ext'),
        );

        availableGames.add(data);
      } catch (e) {
        debugPrint(e.toString());
      }
    }

    // On non-web platforms, also scan local filesystem locations for
    // user-supplied data folders so the host can pick up extra versions.
    final Set<String> directoriesToScan = <String>{};
    if (resolvedDirectory != null && resolvedDirectory.isNotEmpty) {
      directoriesToScan.add(resolvedDirectory);
    }

    if (additionalDirectories != null) {
      for (final String directoryPath in additionalDirectories) {
        final String trimmedPath = directoryPath.trim();
        if (trimmedPath.isNotEmpty) {
          directoriesToScan.add(trimmedPath);
        }
      }
    }

    if (!kIsWeb && directoriesToScan.isNotEmpty) {
      for (final String directoryPath in directoriesToScan) {
        try {
          final externalGames = await WolfensteinLoader.discover(
            directoryPath: directoryPath,
            recursive: true,
          );
          for (var entry in externalGames.entries) {
            if (!availableGames.any((g) => g.version == entry.key)) {
              availableGames.add(entry.value);
            }
          }
        } catch (e) {
          debugPrint("External discovery failed: $e");
        }
      }
    }

    return this;
  }

  /// Loads an asset from the Flutter bundle, returning `null` when absent.
  Future<ByteData?> _tryLoad(String path) async {
    try {
      return await rootBundle.load(path);
    } catch (e) {
      debugPrint("Asset not found: $path");
      return null;
    }
  }
}