import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:media_kit/media_kit.dart';
import 'package:media_kit_video/media_kit_video.dart';
import '../client/plex_client.dart';
import '../models/plex_metadata.dart';
import '../models/plex_user_profile.dart';
import '../widgets/plex_video_controls.dart';
import '../utils/language_codes.dart';
import '../utils/app_logger.dart';

class VideoPlayerScreen extends StatefulWidget {
  final PlexClient client;
  final PlexMetadata metadata;
  final AudioTrack? preferredAudioTrack;
  final SubtitleTrack? preferredSubtitleTrack;
  final PlexUserProfile? userProfile;

  const VideoPlayerScreen({
    super.key,
    required this.client,
    required this.metadata,
    this.preferredAudioTrack,
    this.preferredSubtitleTrack,
    this.userProfile,
  });

  @override
  State<VideoPlayerScreen> createState() => _VideoPlayerScreenState();
}

class _VideoPlayerScreenState extends State<VideoPlayerScreen> {
  late final Player player;
  late final VideoController controller;
  Timer? _progressTimer;
  PlexMetadata? _nextEpisode;
  PlexMetadata? _previousEpisode;
  bool _isLoadingNext = false;
  bool _showPlayNextDialog = false;

  @override
  void initState() {
    super.initState();

    appLogger.d('VideoPlayerScreen initialized for: ${widget.metadata.title}');
    if (widget.userProfile != null) {
      appLogger.d('Using user profile for track selection');
    }
    if (widget.preferredAudioTrack != null) {
      appLogger.d(
        'Preferred audio track: ${widget.preferredAudioTrack!.title ?? widget.preferredAudioTrack!.id} (${widget.preferredAudioTrack!.language ?? "unknown"})',
      );
    }
    if (widget.preferredSubtitleTrack != null) {
      final subtitleDesc = widget.preferredSubtitleTrack!.id == "no"
          ? "OFF"
          : "${widget.preferredSubtitleTrack!.title ?? widget.preferredSubtitleTrack!.id} (${widget.preferredSubtitleTrack!.language ?? "unknown"})";
      appLogger.d('Preferred subtitle track: $subtitleDesc');
    }

    // Create player and controller
    player = Player(configuration: PlayerConfiguration(libass: true));
    controller = VideoController(player);

    // Get the video URL and start playback
    _startPlayback();

    // Set fullscreen mode and landscape orientation
    _setLandscapeOrientation();

    // Listen to playback state changes
    player.stream.playing.listen(_onPlayingStateChanged);

    // Listen to completion
    player.stream.completed.listen(_onVideoCompleted);

    // Start periodic progress updates
    _startProgressTracking();

    // Load next/previous episodes
    _loadAdjacentEpisodes();
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    // Ensure landscape orientation is set even after navigation
    _setLandscapeOrientation();
  }

  void _setLandscapeOrientation() {
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.immersiveSticky);
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeLeft,
      DeviceOrientation.landscapeRight,
    ]);
  }

  Future<void> _loadAdjacentEpisodes() async {
    if (widget.metadata.type.toLowerCase() != 'episode') {
      return;
    }

    try {
      final next = await widget.client.getNextEpisode(widget.metadata);
      final previous = await widget.client.getPreviousEpisode(widget.metadata);

      if (mounted) {
        setState(() {
          _nextEpisode = next;
          _previousEpisode = previous;
        });
      }
    } catch (e) {
      // Silently handle errors
    }
  }

  Future<void> _startPlayback() async {
    try {
      // Get the direct file URL from the server
      final videoUrl = await widget.client.getVideoUrl(
        widget.metadata.ratingKey,
      );

      if (videoUrl != null) {
        // Open video without auto-playing
        await player.open(Media(videoUrl), play: false);

        // Wait for media to be ready (duration > 0)
        int attempts = 0;
        while (player.state.duration.inMilliseconds == 0 && attempts < 50) {
          await Future.delayed(const Duration(milliseconds: 100));
          attempts++;
        }

        // Set up playback position if resuming
        if (widget.metadata.viewOffset != null &&
            widget.metadata.viewOffset! > 0) {
          final resumePosition = Duration(
            milliseconds: widget.metadata.viewOffset!,
          );
          await player.seek(resumePosition);
        }

        // Start playback after seeking
        await player.play();

        // Wait for tracks to be loaded, then apply preferred tracks
        _waitForTracksAndApply();
      } else {
        if (mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(content: Text('Could not find video file')),
          );
        }
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Error: $e')));
      }
    }
  }

  @override
  void dispose() {
    // Stop progress tracking
    _progressTimer?.cancel();

    // Send final stopped state
    _sendProgress('stopped');

    // Restore system UI
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
    // Restore portrait-only orientation
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitUp,
      DeviceOrientation.portraitDown,
    ]);

    player.dispose();
    super.dispose();
  }

  void _startProgressTracking() {
    // Send progress update every 10 seconds
    _progressTimer = Timer.periodic(const Duration(seconds: 10), (timer) {
      if (player.state.playing) {
        _sendProgress('playing');
      }
    });
  }

  AudioTrack? _findBestAudioMatch(
    List<AudioTrack> availableTracks,
    AudioTrack preferred,
  ) {
    if (availableTracks.isEmpty) return null;

    // Filter out auto and no tracks
    final validTracks = availableTracks
        .where((t) => t.id != 'auto' && t.id != 'no')
        .toList();
    if (validTracks.isEmpty) return null;

    // Try to match: index, title, and language
    for (var track in validTracks) {
      if (track.id == preferred.id &&
          track.title == preferred.title &&
          track.language == preferred.language) {
        return track;
      }
    }

    // Try to match: title and language
    for (var track in validTracks) {
      if (track.title == preferred.title &&
          track.language == preferred.language) {
        return track;
      }
    }

    // Try to match: language only
    for (var track in validTracks) {
      if (track.language == preferred.language) {
        return track;
      }
    }

    return null;
  }

  AudioTrack? _findAudioTrackByProfile(
    List<AudioTrack> availableTracks,
    PlexUserProfile profile,
  ) {
    appLogger.d('Audio track selection using user profile');
    appLogger.d(
      'Profile settings - autoSelectAudio: ${profile.autoSelectAudio}, defaultAudioLanguage: ${profile.defaultAudioLanguage}',
    );

    if (availableTracks.isEmpty || !profile.autoSelectAudio) {
      appLogger.d(
        'Cannot use profile: ${availableTracks.isEmpty ? "No tracks available" : "autoSelectAudio is false"}',
      );
      return null;
    }

    final preferredLanguage = profile.defaultAudioLanguage;
    if (preferredLanguage == null || preferredLanguage.isEmpty) {
      appLogger.d('Cannot use profile: No defaultAudioLanguage specified');
      return null;
    }

    // Get all possible language code variations (e.g., "en" → ["en", "eng"])
    final languageVariations = LanguageCodes.getVariations(preferredLanguage);
    appLogger.d(
      'Checking language variations: ${languageVariations.join(", ")}',
    );

    // Try to find track matching any language variation
    for (var track in availableTracks) {
      final trackLang = track.language?.toLowerCase();
      if (trackLang != null && languageVariations.contains(trackLang)) {
        appLogger.d(
          'Found audio track matching profile language "$preferredLanguage" (matched: "$trackLang"): ${track.title ?? "Track ${track.id}"}',
        );
        return track;
      }
    }

    appLogger.d(
      'No audio track found matching profile language "$preferredLanguage" or its variations',
    );
    return null;
  }

  SubtitleTrack? _findBestSubtitleMatch(
    List<SubtitleTrack> availableTracks,
    SubtitleTrack preferred,
  ) {
    // If preferred is "no", return no subtitles
    if (preferred.id == 'no') {
      return SubtitleTrack.no();
    }

    if (availableTracks.isEmpty) return null;

    // Filter out auto and no tracks
    final validTracks = availableTracks
        .where((t) => t.id != 'auto' && t.id != 'no')
        .toList();
    if (validTracks.isEmpty) return null;

    // Try to match: index, title, and language
    for (var track in validTracks) {
      if (track.id == preferred.id &&
          track.title == preferred.title &&
          track.language == preferred.language) {
        return track;
      }
    }

    // Try to match: title and language
    for (var track in validTracks) {
      if (track.title == preferred.title &&
          track.language == preferred.language) {
        return track;
      }
    }

    // Try to match: language only
    for (var track in validTracks) {
      if (track.language == preferred.language) {
        return track;
      }
    }

    return null;
  }

  SubtitleTrack? _findSubtitleTrackByProfile(
    List<SubtitleTrack> availableTracks,
    PlexUserProfile profile,
  ) {
    appLogger.d('Subtitle track selection using user profile');
    appLogger.d(
      'Profile settings - autoSelectSubtitle: ${profile.autoSelectSubtitle}, defaultSubtitleLanguage: ${profile.defaultSubtitleLanguage}, defaultSubtitleForced: ${profile.defaultSubtitleForced}',
    );

    if (availableTracks.isEmpty) {
      appLogger.d('Cannot use profile: No subtitle tracks available');
      return null;
    }

    // If autoSelectSubtitle is 0, don't select any subtitle
    if (!profile.shouldAutoSelectSubtitle) {
      appLogger.d(
        'Profile specifies no auto-select (autoSelectSubtitle=0) - Subtitles OFF',
      );
      return SubtitleTrack.no();
    }

    final preferredLanguage = profile.defaultSubtitleLanguage;
    if (preferredLanguage == null || preferredLanguage.isEmpty) {
      appLogger.d('Cannot use profile: No defaultSubtitleLanguage specified');
      return null;
    }

    // Get all possible language code variations (e.g., "en" → ["en", "eng"])
    final languageVariations = LanguageCodes.getVariations(preferredLanguage);
    appLogger.d(
      'Checking language variations: ${languageVariations.join(", ")}',
    );

    // If defaultSubtitleForced is 1, prefer forced subtitles
    if (profile.preferForcedSubtitles) {
      appLogger.d('Profile prefers forced subtitles (defaultSubtitleForced=1)');
      // Try to find forced subtitle in preferred language
      for (var track in availableTracks) {
        final trackLang = track.language?.toLowerCase();
        if (trackLang != null &&
            languageVariations.contains(trackLang) &&
            track.title?.toLowerCase().contains('forced') == true) {
          appLogger.d(
            'Found forced subtitle matching profile language "$preferredLanguage" (matched: "$trackLang"): ${track.title ?? "Track ${track.id}"}',
          );
          return track;
        }
      }
      appLogger.d(
        'No forced subtitle found in "$preferredLanguage" or its variations, trying regular subtitles',
      );
    }

    // Try to find regular subtitle in preferred language
    for (var track in availableTracks) {
      final trackLang = track.language?.toLowerCase();
      if (trackLang != null && languageVariations.contains(trackLang)) {
        appLogger.d(
          'Found subtitle matching profile language "$preferredLanguage" (matched: "$trackLang"): ${track.title ?? "Track ${track.id}"}',
        );
        return track;
      }
    }

    appLogger.d(
      'No subtitle track found matching profile language "$preferredLanguage" or its variations',
    );
    return null;
  }

  void _waitForTracksAndApply() async {
    // Helper function to process tracks
    Future<void> processTracks(Tracks tracks) async {
      appLogger.d('Starting track selection process');

      // Get real tracks (excluding auto and no)
      final realAudioTracks = tracks.audio
          .where((t) => t.id != 'auto' && t.id != 'no')
          .toList();
      final realSubtitleTracks = tracks.subtitle
          .where((t) => t.id != 'auto' && t.id != 'no')
          .toList();

      appLogger.d('Available audio tracks: ${realAudioTracks.length}');
      for (var track in realAudioTracks) {
        appLogger.d(
          '  - ${track.title ?? "Track ${track.id}"} (${track.language ?? "unknown"}) ${track.isDefault == true ? "[DEFAULT]" : ""}',
        );
      }
      appLogger.d('Available subtitle tracks: ${realSubtitleTracks.length}');
      for (var track in realSubtitleTracks) {
        appLogger.d(
          '  - ${track.title ?? "Track ${track.id}"} (${track.language ?? "unknown"}) ${track.isDefault == true ? "[DEFAULT]" : ""}',
        );
      }

      // Select audio track with priority: preferred > user profile > default > first
      appLogger.d('Audio track selection');
      if (realAudioTracks.isNotEmpty) {
        AudioTrack? trackToSelect;

        // Priority 1: Try to match preferred track from navigation
        if (widget.preferredAudioTrack != null) {
          appLogger.d('Priority 1: Checking preferred track from navigation');
          appLogger.d(
            '  Preferred: ${widget.preferredAudioTrack!.title ?? "Track ${widget.preferredAudioTrack!.id}"} (${widget.preferredAudioTrack!.language ?? "unknown"})',
          );
          trackToSelect = _findBestAudioMatch(
            realAudioTracks,
            widget.preferredAudioTrack!,
          );
          if (trackToSelect != null) {
            appLogger.d('  Matched preferred track');
          } else {
            appLogger.d('  No match found for preferred track');
          }
        } else {
          appLogger.d('Priority 1: No preferred track from navigation');
        }

        // Priority 2: If no preferred track matched, try user profile preferences
        if (trackToSelect == null && widget.userProfile != null) {
          appLogger.d('Priority 2: Checking user profile preferences');
          trackToSelect = _findAudioTrackByProfile(
            realAudioTracks,
            widget.userProfile!,
          );
        } else if (trackToSelect == null) {
          appLogger.d('Priority 2: No user profile available');
        }

        // Priority 3: If no match, use default or first track
        if (trackToSelect == null) {
          appLogger.d('Priority 3: Using default or first available track');
          trackToSelect = realAudioTracks.firstWhere(
            (t) => t.isDefault == true,
            orElse: () => realAudioTracks.first,
          );
          final isDefault = trackToSelect.isDefault == true;
          appLogger.d(
            '  Selected ${isDefault ? "default" : "first"} track: ${trackToSelect.title ?? "Track ${trackToSelect.id}"} (${trackToSelect.language ?? "unknown"})',
          );
        }

        appLogger.i(
          'Final audio selection: ${trackToSelect.title ?? "Track ${trackToSelect.id}"} (${trackToSelect.language ?? "unknown"})',
        );
        player.setAudioTrack(trackToSelect);
      } else {
        appLogger.d('No audio tracks available');
      }

      // Select subtitle track with priority: preferred > user profile > default > off
      appLogger.d('Subtitle track selection');
      SubtitleTrack? subtitleToSelect;

      // Priority 1: Try preferred track from navigation (always wins)
      if (widget.preferredSubtitleTrack != null) {
        appLogger.d('Priority 1: Checking preferred track from navigation');
        if (widget.preferredSubtitleTrack!.id == 'no') {
          appLogger.d('  Preferred: OFF');
          subtitleToSelect = SubtitleTrack.no();
          appLogger.d('  Using preferred setting: Subtitles OFF');
        } else if (realSubtitleTracks.isNotEmpty) {
          appLogger.d(
            '  Preferred: ${widget.preferredSubtitleTrack!.title ?? "Track ${widget.preferredSubtitleTrack!.id}"} (${widget.preferredSubtitleTrack!.language ?? "unknown"})',
          );
          subtitleToSelect = _findBestSubtitleMatch(
            realSubtitleTracks,
            widget.preferredSubtitleTrack!,
          );
          if (subtitleToSelect != null) {
            appLogger.d('  Matched preferred track');
          } else {
            appLogger.d('  No match found for preferred track');
          }
        }
      } else {
        appLogger.d('Priority 1: No preferred track from navigation');
      }

      // Priority 2: If no preferred match, apply user profile preferences
      if (subtitleToSelect == null &&
          widget.userProfile != null &&
          realSubtitleTracks.isNotEmpty) {
        appLogger.d('Priority 2: Checking user profile preferences');
        subtitleToSelect = _findSubtitleTrackByProfile(
          realSubtitleTracks,
          widget.userProfile!,
        );
      } else if (subtitleToSelect == null && realSubtitleTracks.isNotEmpty) {
        appLogger.d('Priority 2: No user profile available');
      }

      // Priority 3: If no profile match, check for default subtitle
      if (subtitleToSelect == null && realSubtitleTracks.isNotEmpty) {
        appLogger.d('Priority 3: Checking for default subtitle track');
        final defaultTrackIndex = realSubtitleTracks.indexWhere(
          (t) => t.isDefault == true,
        );
        if (defaultTrackIndex != -1) {
          subtitleToSelect = realSubtitleTracks[defaultTrackIndex];
          appLogger.d(
            '  Found default track: ${subtitleToSelect.title ?? "Track ${subtitleToSelect.id}"} (${subtitleToSelect.language ?? "unknown"})',
          );
        } else {
          appLogger.d('  No default subtitle track found');
        }
      }

      // If still no subtitle selected, turn off
      if (subtitleToSelect == null) {
        appLogger.d('Priority 4: No subtitle selected - Subtitles OFF');
        subtitleToSelect = SubtitleTrack.no();
      }

      final finalSubtitle = subtitleToSelect.id == 'no'
          ? 'OFF'
          : '${subtitleToSelect.title ?? "Track ${subtitleToSelect.id}"} (${subtitleToSelect.language ?? "unknown"})';
      appLogger.i('Final subtitle selection: $finalSubtitle');
      player.setSubtitleTrack(subtitleToSelect);

      appLogger.d('Track selection complete');
    }

    // Check if tracks are already available in current state
    final currentTracks = player.state.tracks;
    if (currentTracks.audio.isNotEmpty || currentTracks.subtitle.isNotEmpty) {
      await processTracks(currentTracks);
      return;
    }

    // If not, listen to tracks stream for when they become available
    bool applied = false;
    final subscription = player.stream.tracks.listen((tracks) async {
      // Check if tracks are loaded (have at least one track) and not yet applied
      if (!applied && (tracks.audio.isNotEmpty || tracks.subtitle.isNotEmpty)) {
        applied = true;
        await processTracks(tracks);
      }
    });

    // Cancel subscription after timeout
    Future.delayed(const Duration(seconds: 5), () {
      subscription.cancel();
    });
  }

  void _onPlayingStateChanged(bool isPlaying) {
    // Send timeline update when playback state changes
    _sendProgress(isPlaying ? 'playing' : 'paused');
  }

  void _sendProgress(String state) {
    final position = player.state.position.inMilliseconds;
    final duration = player.state.duration.inMilliseconds;

    if (duration > 0) {
      widget.client
          .updateProgress(
            widget.metadata.ratingKey,
            time: position,
            state: state,
            duration: duration,
          )
          .catchError((error) {
            // Silently handle errors - don't interrupt playback
          });
    }
  }

  void _onVideoCompleted(bool completed) {
    if (completed && _nextEpisode != null && !_showPlayNextDialog) {
      setState(() {
        _showPlayNextDialog = true;
      });
    }
  }

  Future<void> _playNext() async {
    if (_nextEpisode == null || _isLoadingNext) return;

    setState(() {
      _isLoadingNext = true;
      _showPlayNextDialog = false;
    });

    // Capture current track selection BEFORE pausing
    final currentAudioTrack = player.state.track.audio;
    final currentSubtitleTrack = player.state.track.subtitle;

    // Pause and stop current playback
    player.pause();
    _progressTimer?.cancel();
    _sendProgress('stopped');

    // Navigate to the next episode using pushReplacement to destroy current player
    if (mounted) {
      Navigator.of(context).pushReplacement(
        MaterialPageRoute(
          builder: (context) => VideoPlayerScreen(
            client: widget.client,
            metadata: _nextEpisode!,
            preferredAudioTrack: currentAudioTrack,
            preferredSubtitleTrack: currentSubtitleTrack,
            userProfile: widget.userProfile,
          ),
        ),
      );
    }
  }

  Future<void> _playPrevious() async {
    if (_previousEpisode == null) return;

    // Capture current track selection BEFORE pausing
    final currentAudioTrack = player.state.track.audio;
    final currentSubtitleTrack = player.state.track.subtitle;

    // Pause and stop current playback
    player.pause();
    _progressTimer?.cancel();
    _sendProgress('stopped');

    // Navigate to the previous episode using pushReplacement to destroy current player
    if (mounted) {
      Navigator.of(context).pushReplacement(
        MaterialPageRoute(
          builder: (context) => VideoPlayerScreen(
            client: widget.client,
            metadata: _previousEpisode!,
            preferredAudioTrack: currentAudioTrack,
            preferredSubtitleTrack: currentSubtitleTrack,
            userProfile: widget.userProfile,
          ),
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return PopScope(
      canPop: true,
      child: Scaffold(
        backgroundColor: Colors.black,
        body: Stack(
          children: [
            // Video player
            Center(
              child: Video(
                controller: controller,
                controls: (state) => plexVideoControlsBuilder(
                  player,
                  widget.client,
                  widget.metadata,
                  onNext: _nextEpisode != null ? _playNext : null,
                  onPrevious: _previousEpisode != null ? _playPrevious : null,
                ),
              ),
            ),
            // Play Next Dialog
            if (_showPlayNextDialog && _nextEpisode != null)
              Positioned.fill(
                child: Container(
                  color: Colors.black.withValues(alpha: 0.8),
                  child: Center(
                    child: Container(
                      margin: const EdgeInsets.symmetric(horizontal: 32),
                      padding: const EdgeInsets.all(32),
                      decoration: BoxDecoration(
                        color: Colors.grey[900],
                        borderRadius: BorderRadius.circular(16),
                      ),
                      child: Column(
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          const Icon(
                            Icons.play_circle_outline,
                            size: 64,
                            color: Colors.white,
                          ),
                          const SizedBox(height: 24),
                          const Text(
                            'Up Next',
                            style: TextStyle(
                              color: Colors.white,
                              fontSize: 24,
                              fontWeight: FontWeight.bold,
                            ),
                          ),
                          const SizedBox(height: 16),
                          Text(
                            _nextEpisode!.grandparentTitle ??
                                _nextEpisode!.title,
                            style: const TextStyle(
                              color: Colors.white,
                              fontSize: 18,
                            ),
                            textAlign: TextAlign.center,
                          ),
                          const SizedBox(height: 8),
                          if (_nextEpisode!.parentIndex != null &&
                              _nextEpisode!.index != null)
                            Text(
                              'S${_nextEpisode!.parentIndex} · E${_nextEpisode!.index} · ${_nextEpisode!.title}',
                              style: const TextStyle(
                                color: Colors.white70,
                                fontSize: 16,
                              ),
                              textAlign: TextAlign.center,
                            ),
                          const SizedBox(height: 32),
                          Row(
                            mainAxisAlignment: MainAxisAlignment.center,
                            children: [
                              OutlinedButton(
                                onPressed: () {
                                  setState(() {
                                    _showPlayNextDialog = false;
                                  });
                                },
                                style: OutlinedButton.styleFrom(
                                  foregroundColor: Colors.white,
                                  side: const BorderSide(color: Colors.white),
                                  padding: const EdgeInsets.symmetric(
                                    horizontal: 32,
                                    vertical: 16,
                                  ),
                                ),
                                child: const Text('Cancel'),
                              ),
                              const SizedBox(width: 16),
                              FilledButton(
                                onPressed: _playNext,
                                style: FilledButton.styleFrom(
                                  backgroundColor: Colors.white,
                                  foregroundColor: Colors.black,
                                  padding: const EdgeInsets.symmetric(
                                    horizontal: 32,
                                    vertical: 16,
                                  ),
                                ),
                                child: const Text('Play Now'),
                              ),
                            ],
                          ),
                        ],
                      ),
                    ),
                  ),
                ),
              ),
          ],
        ),
      ),
    );
  }
}