import 'package:flutter/material.dart';
import 'package:flutter/services.dart'; // SystemChrome, DeviceOrientation 사용을 위해 import
import 'package:youtube_player_flutter/youtube_player_flutter.dart';
import 'common/widgets/custom_bottom_nav_bar.dart';

class YoutubePlayerPage extends StatefulWidget {
  final String lessonUrl;
  final void Function(bool isFullScreen)? onFullScreenToggle;

  const YoutubePlayerPage({
    super.key,
    required this.lessonUrl,
    this.onFullScreenToggle,
  });

  @override
  State<YoutubePlayerPage> createState() => _YoutubePlayerPageState();
}

class _YoutubePlayerPageState extends State<YoutubePlayerPage> {
  YoutubePlayerController? _controller;
  String? _videoId;
  bool _isPlayerReady = false;
  String _videoTitle = 'YouTube Video';
  final int _currentBottomNavIndex = 0;
  bool _isSystemUiVisible = true;
  bool _isLoading = true; // 로딩 상태 추가
  bool _isFullScreen = false;

  @override
  void initState() {
    super.initState();
    _videoId = YoutubePlayer.convertUrlToId(widget.lessonUrl);

    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) {
        final String snackBarMessage;
        if (_videoId != null) {
          snackBarMessage = 'Video ID: $_videoId';
        } else {
          snackBarMessage =
          'Could not extract Video ID from URL: ${widget.lessonUrl}';
        }
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text(snackBarMessage),
            duration: const Duration(seconds: 3),
          ),
        );
      }
    });

    if (_videoId != null) {
      _controller = YoutubePlayerController(
        initialVideoId: _videoId!,
        flags: const YoutubePlayerFlags(
          autoPlay: true,
          mute: false,
        ),
      )..addListener(_playerListener);
    } else {
      _videoTitle = 'Video Error';
    }
  }

  void _playerListener() {
    if (_controller == null || !mounted) return;

    if (_isFullScreen != _controller!.value.isFullScreen) {
      setState(() {
        _isFullScreen = _controller!.value.isFullScreen;
      });
      widget.onFullScreenToggle?.call(_isFullScreen);

      if (_isFullScreen) {
        _hideSystemUi();
      } else {
        _showSystemUi();
        SystemChrome.setPreferredOrientations([
          DeviceOrientation.portraitUp,
          DeviceOrientation.portraitDown,
        ]);
      }
    }

    if (_controller!.value.playerState == PlayerState.ended) {
      if (mounted) {
        if (_controller!.value.isFullScreen) {
          _controller!.toggleFullScreenMode();
        }
      }
      return;
    }

    if (_isPlayerReady) {
      if (_controller!.metadata.title.isNotEmpty &&
          _videoTitle != _controller!.metadata.title) {
        if (mounted) {
          setState(() {
            _videoTitle = _controller!.metadata.title;
          });
        }
      }
    }
  }

  void _hideSystemUi() {
    if (!_isSystemUiVisible) return;
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.immersiveSticky);
    if (mounted) {
      setState(() {
        _isSystemUiVisible = false;
      });
    }
  }

  void _showSystemUi() {
    if (_isSystemUiVisible) return;
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
    if (mounted) {
      setState(() {
        _isSystemUiVisible = true;
      });
    }
  }

  void _onNotificationTapped() {
    ScaffoldMessenger.of(context).showSnackBar(
      const SnackBar(content: Text('알림 아이콘 클릭됨')),
    );
  }

  void _onProfileTapped() {
    ScaffoldMessenger.of(context).showSnackBar(
      const SnackBar(content: Text('프로필 아이콘 클릭됨')),
    );
  }

  void _onBottomNavItemTapped(int index) {
    if (_currentBottomNavIndex == index && index != 0) return;
    if (index == 0) {
      Navigator.of(context).popUntil((route) => route.isFirst);
    } else {
      String tabName = '';
      switch (index) {
        case 1:
          tabName = 'Plan';
          break;
        case 2:
          tabName = 'Statistics';
          break;
        case 3:
          tabName = 'Career'; // New case for Jobs
          break;
        case 4:
          tabName = 'More'; // Updated case for More
          break;
      }
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text('$tabName 탭으로 이동 (구현 필요)')),
      );
    }
  }

  @override
  void didUpdateWidget(covariant YoutubePlayerPage oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (widget.lessonUrl != oldWidget.lessonUrl) {
      _videoId = YoutubePlayer.convertUrlToId(widget.lessonUrl);
      if (_videoId != null) {
        _controller?.load(_videoId!); // 새 비디오 로드
      } else {
        if (mounted) {
          setState(() {
            _videoTitle = 'Video Error';
          });
        }
      }
    }
  }

  // <<< 뒤로가기 버튼 처리 로직 >>>
  Future<bool> _onWillPop() async {
    if (_controller != null && _controller!.value.isFullScreen) {
      _controller!.toggleFullScreenMode(); // 전체 화면 해제
      // _playerListener에서 화면 방향은 자동으로 세로로 설정될 것임
      // _showSystemUi(); // 시스템 UI도 _playerListener에서 처리
      return false; // 뒤로가기(페이지 pop) 막음
    }
    // 전체 화면이 아닐 때는 일반적인 뒤로 가기 동작 허용
    return true;
  }

  @override
  Widget build(BuildContext context) {
    final bool isFullScreen = _controller?.value.isFullScreen ?? false;

    // <<< WillPopScope로 Scaffold를 감싸서 뒤로가기 이벤트 가로채기 >>>
    return WillPopScope(
      onWillPop: _onWillPop,
      child: Scaffold(
        extendBodyBehindAppBar: isFullScreen,

        body: Column( // <--- Wrap the body content in a Column
          children: [
            Expanded( // <--- Wrap the main content with Expanded
              child: Center(
                child: _controller == null
                    ? Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          const Icon(Icons.error_outline,
                              color: Colors.red, size: 50),
                          const SizedBox(height: 10),
                          Padding(
                            padding: const EdgeInsets.symmetric(horizontal: 20.0),
                            child: Text(
                              '비디오를 로드할 수 없습니다.\nURL: ${widget.lessonUrl}',
                              textAlign: TextAlign.center,
                              style: const TextStyle(fontSize: 16),
                              overflow: TextOverflow.ellipsis,
                            ),
                          ),
                        ],
                      )
                    : YoutubePlayer(
                        controller: _controller!,
                        showVideoProgressIndicator: true,
                        progressIndicatorColor: Colors.amber,
                        progressColors: const ProgressBarColors(
                          playedColor: Colors.amber,
                          handleColor: Colors.amberAccent,
                        ),
                        onReady: () {
                          if (mounted) {
                            setState(() {
                              _isPlayerReady = true;
                              if (_controller!.metadata.title.isNotEmpty) {
                                _videoTitle = _controller!.metadata.title;
                              }
                            });
                          }

                        },
                      ),
              ),
            ),
          ],
        ),
        bottomNavigationBar: isFullScreen
            ? null
            : CustomBottomNavBar(
                currentIndex: _currentBottomNavIndex,
                onTap: _onBottomNavItemTapped,
              ),
      ),
    );
  }

  @override
  void deactivate() {
    // 페이지가 비활성화될 때 (예: 다른 화면으로 전환될 때) 플레이어 일시 중지
    if (_controller != null && _isPlayerReady && _controller!.value.isPlaying) {
      _controller!.pause();
    }
    super.deactivate();
  }

  @override
  void dispose() {
    // <<< 페이지 종료 시 기본 화면 방향으로 복구 또는 모든 방향 허용 >>>
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitUp,
      DeviceOrientation.portraitDown,
      // DeviceOrientation.landscapeLeft, // 필요에 따라 가로모드도 허용
      // DeviceOrientation.landscapeRight,
    ]);
    // 또는: SystemChrome.setPreferredOrientations(DeviceOrientation.values); // 모든 방향 허용

    // 시스템 UI 복구 (이미 _showSystemUi()가 있지만, 명시적으로 호출)
    // _showSystemUi(); // 이 로직은 _isSystemUiVisible 상태에 따라 실행되므로 안전
    // 또는 강제로 UI를 보이게 하려면:
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);


    _controller?.removeListener(_playerListener);
    _controller?.dispose();
    super.dispose();
  }
}