import 'dart:io';
import 'dart:async';
import 'dart:convert';
import 'package:shelf/shelf.dart';
import 'package:shelf/shelf_io.dart' as shelf_io;
import 'package:shelf_static/shelf_static.dart';
import 'package:shelf_router/shelf_router.dart';
import 'package:args/args.dart';
import 'database/database.dart';
import 'models/user.dart';
import 'models/playlist.dart';
import 'models/playlist_config.dart';
import 'api/auth_handler.dart';
import 'api/users_handler.dart';
import 'api/playlists_handler.dart';
import 'api/settings_handler.dart';
import 'api/streaming_handler.dart';
import 'api/proxy_handler.dart';
import 'api/recordings_api.dart';
import 'api/epg_api.dart';
import 'api/logo_api.dart';
import 'services/xmltv_epg_service.dart';
import 'services/logo_catalog.dart';
import 'api/season_passes_api.dart';
import 'api/xtream_api_handler.dart';
import 'middleware/auth_middleware.dart';
import 'middleware/security_middleware.dart';
import 'services/cleanup_service.dart';
import 'services/recording_scheduler.dart';
import 'utils/asset_versioning.dart';
import 'api/upstream_probe.dart';
import 'api/player_log.dart';

void main(List<String> args) async {
  // Parse command line arguments
  final parser = ArgParser()
    ..addOption('port', abbr: 'p', defaultsTo: '8089')
    ..addOption('path', defaultsTo: '/app/web');

  final result = parser.parse(args);
  final port = int.parse(result['port']);
  final webPath = result['path'];

  // Initialize database
  final db = AppDatabase();
  await db.init();
  await db.seedAdmin();

  // Initialize and start Recording Scheduler
  // (les Season Passes résolvent la playlist de leur propriétaire à chaque
  // scan : plus d'injection figée du premier utilisateur au démarrage)
  final recordingScheduler = RecordingScheduler(db);
  recordingScheduler.start();

  // Initialize Streaming Subsystem
  await initStreaming();

  // Arrêt gracieux unique (docker stop / Ctrl+C) : clôturer d'abord les
  // enregistrements (kill FFmpeg, fusion des parties, statut en base), puis
  // les sessions de streaming, puis sortir. Sans cela les enregistrements
  // restaient au statut « recording » et la reprise d'orphelins devait
  // systématiquement rattraper au redémarrage.
  var shuttingDown = false;
  Future<void> shutdownServer(String signal) async {
    if (shuttingDown) return;
    shuttingDown = true;
    print('[Server] $signal reçu, arrêt en cours…');
    try {
      await recordingScheduler.shutdown();
    } catch (e) {
      print('[Server] Erreur à l\'arrêt du scheduler: $e');
    }
    sessionManager.killAll();
    db.close();
    exit(0);
  }

  ProcessSignal.sigterm.watch().listen((_) => shutdownServer('SIGTERM'));
  ProcessSignal.sigint.watch().listen((_) => shutdownServer('SIGINT'));

  // Helper to get playlist from request
  Future<PlaylistConfig?> getPlaylist(Request request) async {
    Playlist? playlist;

    final user = request.context['user'] as User?;
    // If we have a user from auth middleware, prefer their playlists
    if (user != null) {
      print('[getPlaylist] User from context: ${user.username}');
      final playlists = db.getPlaylists(user.id);
      if (playlists.isNotEmpty) playlist = playlists.first;
    } else {
      // Fallback for proxy: get first user's first playlist
      print('[getPlaylist] No user in context, using fallback');
      final users = db.getAllUsers();
      print('[getPlaylist] Total users in DB: ${users.length}');
      if (users.isNotEmpty) {
        final playlists = db.getPlaylists(users[0].id);
        print(
          '[getPlaylist] User ${users[0].username} has ${playlists.length} playlists',
        );
        if (playlists.isNotEmpty) playlist = playlists.first;
      }
    }

    if (playlist != null) {
      print(
        '[getPlaylist] Returning playlist: ${playlist.name} (DNS: ${playlist.serverUrl})',
      );
      return PlaylistConfig(
        id: playlist.id,
        name: playlist.name,
        dns: playlist.serverUrl,
        username: playlist.username,
        password: playlist.password,
        createdAt: playlist.createdAt,
        isActive: true,
      );
    }
    print('[getPlaylist] WARNING: No playlist found, returning null');
    return null;
  }

  // Create API handlers
  final authHandler = AuthHandler(db);
  final playlistsHandler = PlaylistsHandler(db);
  final usersHandler = UsersHandler(db);
  final settingsHandler = SettingsHandler(db);
  final proxyHandler = ProxyHandler(getPlaylist, db);
  // Logos de chaînes : URL du panneau d'abord, puis repli par nom sur le
  // dépôt public tv-logos quand l'hébergeur de picons du revendeur tombe.
  final logoApi = LogoApi(proxyHandler.handler, LogoCatalog());
  final recordingsApi = RecordingsApi(db, recordingScheduler);
  // Source XMLTV de repli. Vider EPG_XMLTV_URLS désactive tout appel sortant :
  // l'EPG se limite alors au panneau de l'abonné.
  final xmltvUrls = (Platform.environment['EPG_XMLTV_URLS'] ??
          'https://epgshare01.online/epgshare01/epg_ripper_FR1.xml.gz,'
          'https://epgshare01.online/epgshare01/epg_ripper_CH1.xml.gz,'
          'https://epgshare01.online/epgshare01/epg_ripper_BE2.xml.gz')
      .split(',')
      .map((u) => u.trim())
      .where((u) => u.isNotEmpty)
      .toList();
  if (xmltvUrls.isEmpty) {
    print('[EPG] Repli XMLTV désactivé (EPG_XMLTV_URLS vide)');
  } else {
    print('[EPG] Repli XMLTV : ${xmltvUrls.length} source(s)');
  }
  final epgApi = EpgApi(
    getPlaylist,
    xmltv: xmltvUrls.isEmpty ? null : XmltvEpgService(sourceUrls: xmltvUrls),
  );
  final seasonPassesApi = SeasonPassesApi(db);
  final xtreamApiHandler = XtreamApiHandler(getPlaylist);

  // TV Recordings sub-router (wrapped with auth below).
  // NOTE: /api/recordings/stream/* falls through this router (404) and is
  // handled by streamingRouter further down the Cascade.
  final recordingsRouter = Router()
    ..get('/', recordingsApi.handleGetAll)
    ..post('/', recordingsApi.handlePost)
    ..delete('/<id>', recordingsApi.handleDelete)
    ..post('/stop/<id>', recordingsApi.handleStop)
    ..get('/logs/<id>', recordingsApi.getLogHandler);

  final epgRouter = Router()..get('/<channelId>', epgApi.handleGetEpg);

  final seasonPassesRouter = Router()
    ..get('/', seasonPassesApi.handleGetAll)
    ..post('/', seasonPassesApi.handlePost)
    ..delete('/<id>', seasonPassesApi.handleDelete);

  // Setup router
  final apiRouter = Router()
    // Auth endpoints (with per-IP brute-force protection on login)
    ..mount(
      '/api/auth',
      const Pipeline()
          .addMiddleware(loginRateLimitMiddleware())
          .addHandler(authHandler.router.call),
    )
    // Xtream API gateway: injects credentials server-side so the
    // frontend never sees them
    ..mount(
      '/api/xtream-api',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(xtreamApiHandler.handle),
    )
    // Playlists endpoints
    ..mount(
      '/api/playlists',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(playlistsHandler.router.call),
    )
    // Users endpoints
    ..mount(
      '/api/users',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(usersHandler.router.call),
    )
    // Settings endpoints
    ..mount(
      '/api/settings',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(settingsHandler.router.call),
    )
    // TV Recordings (auth required)
    ..mount(
      '/api/recordings',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(recordingsRouter.call),
    )
    // Logos de chaînes avec repli (auth required ; le cookie de session
    // accompagne les requêtes d'image du navigateur)
    ..get(
      '/api/logo',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(logoApi.handle),
    )
    // Incidents de lecture remontés par le lecteur web (freezes, erreurs),
    // écrits dans les logs pour le diagnostic.
    ..post(
      '/api/player-log',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(handlePlayerLog),
    )
    // EPG - guide TV (auth required)
    ..mount(
      '/api/epg',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(epgRouter.call),
    )
    // Season Passes - enregistrements répétés (auth required)
    ..mount(
      '/api/season-passes',
      const Pipeline()
          .addMiddleware(authMiddleware(db))
          .addHandler(seasonPassesRouter.call),
    );
  // NOTE: /api/xtream is handled by proxyHandler in the Cascade below
  // Do NOT mount here as it would intercept and block the actual proxy

  // Initialize Cleanup Service
  // Ne JAMAIS cibler Directory.systemTemp en récursif : il contient les
  // temporaires de la VM Dart et le dossier des sessions HLS — les fichiers
  // de plus de 24 h y étaient supprimés aveuglément.
  final cleanupService = CleanupService();
  cleanupService.addTarget(Directory('/app/data/logs'));
  cleanupService.addTarget(Directory('/app/data/tmp'));

  cleanupService.start();

  // Admin Routes (protected)
  apiRouter.mount(
    '/api/admin',
    const Pipeline()
        .addMiddleware(authMiddleware(db))
        .addHandler((Request request) {
      final router = Router();

      // POST /api/admin/purge
      router.post('/purge', (Request req) async {
        final user = req.context['user'] as User?;
        if (user == null || !user.isAdmin) {
          return Response.forbidden(
            jsonEncode({'error': 'Admin access required'}),
          );
        }

        final result = await cleanupService.runCleanup();
        return Response.ok(
          jsonEncode(result),
          headers: {'content-type': 'application/json'},
        );
      });

      // GET /api/admin/upstream-probe?stream=<id> : chronomètre l'ouverture
      // d'une chaîne chez le fournisseur en .ts et en .m3u8 (diagnostic du
      // délai de zap ; aucun identifiant dans la réponse).
      router.get('/upstream-probe', (Request req) async {
        final user = req.context['user'] as User?;
        if (user == null || !user.isAdmin) {
          return Response.forbidden(
            jsonEncode({'error': 'Admin access required'}),
          );
        }
        final streamId = req.url.queryParameters['stream'] ?? '';
        if (!RegExp(r'^[0-9]+$').hasMatch(streamId)) {
          return Response.badRequest(body: 'stream=<id numérique> requis');
        }
        final playlist = await getPlaylist(req);
        if (playlist == null) return Response.forbidden('No playlist');
        final result = await probeUpstream(playlist, streamId);
        return Response.ok(
          jsonEncode(result),
          headers: {'content-type': 'application/json'},
        );
      });

      return router(request);
    }),
  );

  // Les libs de lecture sont servies depuis l'image, plus depuis un CDN : si
  // elles manquent (build web incomplet, copie Docker partielle), le lecteur
  // échoue côté navigateur avec un simple « Échec du chargement » sans que
  // rien ne l'ait signalé au démarrage. On le dit ici, une fois, clairement.
  for (final lib in const ['hls.min.js', 'mpegts.min.js']) {
    final file = File('$webPath/vendor/$lib');
    if (!file.existsSync()) {
      print(
        '[Server] ATTENTION: web/vendor/$lib absent de $webPath — '
        'la lecture échouera dans le navigateur.',
      );
    }
  }

  // Create static handler
  final baseStaticHandler = createStaticHandler(
    webPath,
    defaultDocument: 'index.html',
    listDirectories: false,
  );

  // Points d'entrée réécrits avec `?v=<empreinte>` sur leurs JS : voir
  // asset_versioning.dart (un proxy qui cache les .js servait l'ancienne
  // app et l'ancien lecteur après chaque déploiement).
  final versionedEntryPoints = buildVersionedEntryPoints(webPath);
  print('[Server] Assets versionnés : ${versionedEntryPoints.keys.join(', ')}');

  // Wrap static handler to enforce cache policies
  FutureOr<Response> staticHandler(Request request) async {
    final path = request.url.path;

    final versioned =
        versionedEntryPoints[path.isEmpty ? 'index.html' : path];
    if (versioned != null && request.method == 'GET') {
      return Response.ok(
        versioned,
        headers: {
          'Content-Type': path.endsWith('.js')
              ? 'text/javascript; charset=utf-8'
              : 'text/html; charset=utf-8',
          'Cache-Control': 'no-store, no-cache, must-revalidate, max-age=0',
          'Pragma': 'no-cache',
          'Expires': '0',
        },
      );
    }

    final response = await baseStaticHandler(request);

    // Disable cache for entry points to ensure updates are seen immediately.
    // Vendored player libraries (hls.js/mpegts.js, ~750 KB) are pinned
    // versions: keep them cacheable or every player open re-downloads them.
    final isVendored = path.startsWith('vendor/');
    if (!isVendored &&
        (path.isEmpty ||
            path.endsWith('.html') ||
            path.endsWith('.js') ||
            path.endsWith('.json'))) {
      return response.change(
        headers: {
          'Cache-Control': 'no-store, no-cache, must-revalidate, max-age=0',
          'Pragma': 'no-cache',
          'Expires': '0',
        },
      );
    }

    // Allow aggressive caching for hashed assets
    return response.change(
      headers: {
        'Cache-Control': 'public, max-age=86400',
      },
    );
  }

  // Create Streaming Router (Mount handlers on correct paths)
  final streamingRouter = Router()
    ..mount(
      '/api/live',
      createLiveStreamHandler(
        getPlaylist,
        isGpuEnabled: db.isNvidiaGpuEnabled,
      ),
    )
    ..mount(
      '/api/vod',
      createVodStreamHandler(
        getPlaylist,
        isGpuEnabled: db.isNvidiaGpuEnabled,
      ),
    )
    ..mount(
      '/api/recordings/stream',
      createRecordingStreamHandler(
        db,
        isGpuEnabled: db.isNvidiaGpuEnabled,
      ),
    );

  // Proxy Handler (auth is now handled INSIDE the handler, after path check)
  // This allows non-/api/xtream requests to fall through to static handler
  final proxyPipeline = proxyHandler.handler;

  // Streaming routes accept the HttpOnly session cookie (hls.js cannot send
  // Authorization headers); local FFmpeg loopback fetches bypass auth.
  final protectedStreaming = const Pipeline()
      .addMiddleware(streamAuthMiddleware(db))
      .addHandler(streamingRouter.call);

  // Main handler
  final handler = Cascade()
      .add(apiRouter.call) /* Standard API endpoints */
      .add(proxyPipeline) /* Xtream Proxy (auth inside handler) */
      .add(protectedStreaming) /* Streaming endpoints */
      .add(staticHandler)
      .handler;

  // Add middleware
  // redactedLogRequests remplace logRequests() : l'URI de /api/xtream/<url>
  // contient username/password Xtream en clair.
  final pipeline = const Pipeline()
      .addMiddleware(redactedLogRequests())
      .addMiddleware(securityHeadersMiddleware())
      .addMiddleware(honeypotMiddleware())
      .addMiddleware(rateLimitMiddleware())
      .addMiddleware(_corsMiddleware())
      .addHandler(handler);

  // Start server
  final server = await shelf_io.serve(
    pipeline,
    InternetAddress.anyIPv4,
    port,
  );

  print('Server started on port ${server.port}');
  print('Serving static files from: $webPath');
  print('REST API available at: /api/auth/* and /api/playlists/*');
  print('Xtream proxy available at: /api/xtream/* (SSRF Protected)');

  // Clean expired sessions periodically (every hour)
  Timer.periodic(const Duration(hours: 1), (_) {
    db.cleanExpiredSessions();
    print('Cleaned expired sessions');
  });
}

/// CORS middleware.
///
/// The app is served same-origin by this server, so CORS headers are only
/// needed for development (Flutter dev server on another port) or an
/// explicitly configured external origin via the ALLOWED_ORIGIN env var.
/// The request Origin is echoed back only when it matches the allowlist —
/// never a wildcard.
Middleware _corsMiddleware() {
  final extraOrigin = Platform.environment['ALLOWED_ORIGIN'];

  bool isAllowed(String origin) {
    if (extraOrigin != null && extraOrigin.isNotEmpty && origin == extraOrigin) {
      return true;
    }
    // Local development origins (flutter run -d chrome, etc.)
    final uri = Uri.tryParse(origin);
    return uri != null && (uri.host == 'localhost' || uri.host == '127.0.0.1');
  }

  return (Handler handler) {
    return (Request request) async {
      final origin = request.headers['origin'];
      final headers = <String, String>{
        if (origin != null && isAllowed(origin)) ...{
          'Access-Control-Allow-Origin': origin,
          'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE, OPTIONS',
          'Access-Control-Allow-Headers':
              'Origin, Content-Type, Accept, Authorization, Range',
          'Access-Control-Expose-Headers': 'Content-Length, Content-Range',
          'Access-Control-Allow-Credentials': 'true',
          'Vary': 'Origin',
        },
      };

      // Handle preflight requests
      if (request.method == 'OPTIONS') {
        return Response.ok('', headers: headers);
      }

      // Process request and add CORS headers to response
      final response = await handler(request);
      return headers.isEmpty ? response : response.change(headers: headers);
    };
  };
}