import 'dart:async';
import 'package:flutter/material.dart';
import 'package:qhd_prevention/pages/home/study/take_exam_page.dart';
import 'package:qhd_prevention/pages/home/study/study_practise_page.dart';
import 'package:qhd_prevention/pages/my_appbar.dart';
import 'package:qhd_prevention/customWidget/custom_alert_dialog.dart';
import 'package:qhd_prevention/customWidget/custom_button.dart';
import 'package:qhd_prevention/http/ApiService.dart';
import 'package:qhd_prevention/tools/tools.dart';
import 'package:video_player/video_player.dart';

import '../../../customWidget/video_player_widget.dart';
import '../../../http/HttpManager.dart';
import 'face_ecognition_page.dart';

class StudyDetailPage extends StatefulWidget {
  final Map studyDetailDetail;
  final String studentId;
  const StudyDetailPage(this.studyDetailDetail, this.studentId, {super.key});

  @override
  State<StudyDetailPage> createState() => _StudyDetailPageState();
}

class _StudyDetailPageState extends State<StudyDetailPage>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;
  Map<String, dynamic>? _info;
  List<dynamic> _videoList = [];
  bool _loading = true;

  // player controller extracted
  VideoPlayerController? _videoController;
  String _videoCoverUrl = '';

  Timer? _faceTimer;
  bool _throttleFlag = false;
  late int _faceTime;
  late String _classId;
  late String _classCurriculumId;

  Map<String, dynamic>? _currentVideoData;
  int _currentFirstIndex = 0;
  int _currentNodeIndex = 0;
  bool _hasNodes = false;
  Duration _lastReported = Duration.zero;

  @override
  void initState() {
    super.initState();
    _classId = widget.studyDetailDetail['CLASS_ID'] ?? '';
    _classCurriculumId = widget.studyDetailDetail['CLASSCURRICULUM_ID'] ?? '';
    _tabController = TabController(length: 2, vsync: this);
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _showFaceIntro();
      _loadData();
    });
  }

  @override
  void dispose() {
    _tabController.dispose();
    _videoController?.removeListener(_onTimeUpdate);
    _videoController?.dispose();
    _faceTimer?.cancel();
    super.dispose();
  }

  Future<void> _showFaceIntro() async {
    await showDialog(
      context: context,
      builder: (_) => CustomAlertDialog(
        title: '温馨提示',
        content:
        '重要提醒：尊敬的用户，根据规定我们会在您学习过程中多次进行人脸识别认证，为了保护您的隐私请您在摄像设备视野内确保衣冠整齐。',
        cancelText: '取消',
        confirmText: '同意并继续',
        onCancel: () => Navigator.of(context).pop(),
        onConfirm: () => {},
      ),
    );
  }

  Future<void> _loadData() async {
    try {
      final res = await ApiService.getStudyDetailList(
        _classId,
        _classCurriculumId,
        widget.studentId,
      );
      final pd = res['pd'] ?? {};
      _faceTime = int.tryParse(pd['FACE_TIME']?.toString() ?? '10') ?? 10;
      _videoList = List.from(pd['VIDEOLIST'] ?? []);
      // set initial face time
      if (pd['ISFACE'] == '1') {
        await ApiService.fnSetUserFaceTime(_faceTime);
      }
      // compute percent
      for (var item in _videoList) {
        if (item['nodes'] is List && (item['nodes'] as List).isNotEmpty) {
          for (var node in item['nodes']) {
            node['percent'] = _calcPercentStr(
              playCount: node['PLAYCOUNT'],
              resourceTime: node['RESOURCETIME'],
              videoTime: node['VIDEOTIME'],
            );
          }
        } else {
          item['percent'] = _calcPercentStr(
            playCount: item['PLAYCOUNT'],
            resourceTime: item['RESOURCETIME'],
            videoTime: item['VIDEOTIME'],
          );
        }
      }
      setState(() {
        _info = pd;
        _loading = false;
      });
    } catch (_) {
      setState(() => _loading = false);
    }
  }

  String _calcPercentStr({
    required dynamic playCount,
    required dynamic resourceTime,
    required dynamic videoTime,
  }) {
    final seen = int.tryParse('$playCount') ?? 0;
    if (seen > 0) return '100%';
    final resT = double.tryParse('$resourceTime') ?? 0.0;
    final vidT = double.tryParse('$videoTime') ?? 0.0;
    if (vidT == 0) return '0%';
    final pct = ((resT / vidT) * 100).clamp(0, 100).toStringAsFixed(0);
    return '$pct%';
  }

  Future<void> _onVideoTap(
      Map<String, dynamic> data,
      bool hasNodes,
      int fi,
      int ni,
      ) async {
    // clear face timer on backend
    await ApiService.fnClearUserFaceTime();
    _faceTimer?.cancel();
    if (_currentVideoData != null && _lastReported > Duration.zero) {
      await _submitPlayTime(end: false, seconds: _lastReported.inSeconds);
    }
    _lastReported = Duration.zero;

    _currentVideoData = data;
    _hasNodes = hasNodes;
    _currentFirstIndex = fi;
    _currentNodeIndex = ni;

    // pause existing
    _videoController?.pause();

    await _navigateFaceIfNeeded(() async {
      if ((data['IS_VIDEO'] ?? 0) == 1) {
        // document
        if (data['VIDEOFILES'] != null) {
          await pushPage(
            StudyPractisePage(data['VIDEOCOURSEWARE_ID']),
            context,
          );
          await _submitPlayTime(
            end: true,
            seconds: int.parse(data['VIDEOTIME'] ?? '0'),
          );
        } else {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(content: Text('课件文件资源已失效，请联系管理员')),
          );
        }
      } else {
        // video
        await _getVideoPlayInfo(data['VIDEOCOURSEWARE_ID']);
        _startFaceTimer();
      }
    });
  }

  Future<void> _navigateFaceIfNeeded(FutureOr<void> Function() onPass) async {
    if (_info?['ISFACE'] == '1') {
      final passed = await pushPage<bool>(
        FaceRecognitionPage(studentId: widget.studentId, mode: FaceMode.auto),
        context,
      );
      if (passed == true) {
        await onPass();
      } else {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('人脸验证未通过，无法继续')),
        );
      }
    } else {
      await onPass();
    }
  }

  Future<void> _getVideoPlayInfo(String vidId) async {
    final res = await ApiService.fnGetVideoPlayInfo(vidId);
    final url = res['videoList']?[0]?['playURL'] ?? '';
    _videoCoverUrl = res['videoBase']?['coverURL'] ?? '';

    final prog = await ApiService.fnGetVideoPlayProgress(
      vidId,
      _currentVideoData!['CURRICULUM_ID'],
      _classId,
      widget.studentId,
    );
    final seen = (double.tryParse(prog['pd']?['RESOURCETIME']) ?? 0.0).toInt();

    _videoController?.removeListener(_onTimeUpdate);
    _videoController?.dispose();
    _videoController = VideoPlayerController.networkUrl(Uri.parse(url));
    await _videoController!.initialize();
    setState(() {});

    _videoController!
      ..seekTo(Duration(seconds: seen))
      ..play()
      ..addListener(_onTimeUpdate);
  }

  void _onTimeUpdate() {
    if (_videoController == null || !_videoController!.value.isPlaying) return;
    final curr = _videoController!.value.position;
    if (!_throttleFlag && (curr - _lastReported).inSeconds >= 5) {
      _throttleFlag = true;
      _lastReported = curr;
      _submitPlayTime(end: false, seconds: curr.inSeconds)
          .whenComplete(() => _throttleFlag = false);
    }
    final pos = _videoController!.value.position;
    final dur = _videoController!.value.duration;
    if (pos >= dur) {
      _submitPlayTime(end: true, seconds: dur.inSeconds);
      ApiService.fnClearUserFaceTime();
      _faceTimer?.cancel();
    }
  }

  Future<void> _submitPlayTime({
    required bool end,
    required int seconds,
  }) async {
    if (_currentVideoData == null) return;

    try {
      final pd = (await ApiService.fnSubmitPlayTime(
        _currentVideoData!['VIDEOCOURSEWARE_ID'],
        _currentVideoData!['CURRICULUM_ID'],
        end ? '1' : '0',
        seconds,
        _currentVideoData!['CHAPTER_ID'],
        widget.studentId,
        _classCurriculumId,
        _classId,
      ))['pd']!;

      // 更新进度显示
      final comp = pd['PLAYCOUNT'] != null && pd['PLAYCOUNT'] > 0;
      final resT = pd['RESOURCETIME'] ?? seconds;
      final pct = comp
          ? 100
          : (resT / (_currentVideoData!['VIDEOTIME'] ?? 1) * 100)
          .clamp(0, 100);
      final str = '${pct.floor()}%';
      setState(() {
        if (_hasNodes) {
          _videoList[_currentFirstIndex]['nodes'][_currentNodeIndex]
          ['percent'] = str;
        } else {
          _videoList[_currentFirstIndex]['percent'] = str;
        }
      });

      // 如果结束且可考试，弹框
      if (end && pd['CANEXAM'] == '1') {
        _videoController?.pause();
        final ok = await showDialog<bool>(
          context: context,
          builder: (_) => CustomAlertDialog(
            title: '提示',
            content: '当前任务内所有课程均已学完，是否直接参加考试？',
            confirmText: '是',
            cancelText: '否',
          ),
        ) ??
            false;
        if (ok) {
          final arguments = {
            'STAGEEXAMPAPERINPUT_ID':
            pd['paper']['STAGEEXAMPAPERINPUT_ID'],
            'CLASS_ID': _classId,
            'STUDENT_ID': widget.studentId,
            'NUMBEROFEXAMS': pd['NUMBEROFEXAMS'],
          };
          pushPage(TakeExamPage(arguments), context);
        } else {
          _videoController?.play();
        }
      }
    } on ApiException catch (e) {
      // 如果是 401 ，就登出并跳转登录

      // 其他错误继续抛出
      rethrow;
    }
  }


  void _startFaceTimer() {
    _faceTimer = Timer.periodic(Duration(seconds: _faceTime), (_) async {
      final res = await ApiService.fnGetUserFaceTime(_faceTime);
      final isPlaying = _videoController?.value.isPlaying == true;
      final isVideo = _currentVideoData?['IS_VIDEO'] == 0;
      final needAuth = res['data'] == false;

      if (isPlaying && isVideo && needAuth) {
        _videoController!.pause();
        _videoController!.removeListener(_onTimeUpdate);
        await _showFaceAuthOnce();
      }
    });
  }

  Future<void> _showFaceAuthOnce() async {
    final passed = await pushPage<bool>(
      FaceRecognitionPage(studentId: widget.studentId, mode: FaceMode.auto),
      context,
    );
    if (passed == true) {
      await _videoController?.play();
      setState(() {});
      _faceTimer?.cancel();
    }
  }


  void _controllerListener() {
    if (mounted) setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    if (_loading) {
      return Scaffold(
        appBar: MyAppbar(title: '学习详情'),
        body: const Center(child: CircularProgressIndicator()),
      );
    }
    final info = _info!;
    return Scaffold(
      appBar: MyAppbar(title: '学习详情'),
      body: SafeArea(
        child: Column(
          children: [
            SizedBox(
              height: 250,
              child: VideoPlayerWidget(
                controller: _videoController,
                coverUrl: _videoCoverUrl.isNotEmpty
                    ? ApiService.baseImgPath + _videoCoverUrl
                    : ApiService.baseImgPath + (info['COVERPATH'] ?? ''),
                aspectRatio: _videoController?.value.aspectRatio ?? 16/9,
              ),
            ),
            Container(
              width: double.infinity,
              color: Colors.white,
              padding: const EdgeInsets.all(10.0),
              child: Text(
                info['CURRICULUMNAME'] ?? '',
                style: const TextStyle(
                  fontSize: 20,
                  fontWeight: FontWeight.bold,
                ),
              ),
            ),
            const SizedBox(height: 10),
            Container(
              color: Colors.white,
              child: TabBar(
                indicatorColor: Colors.blue,
                labelStyle: const TextStyle(
                  fontSize: 16,
                  color: Colors.black87,
                ),
                controller: _tabController,
                tabs: const [Tab(text: '课件目录'), Tab(text: '详情')],
              ),
            ),
            const SizedBox(height: 10),
            Expanded(
              child: TabBarView(
                controller: _tabController,
                children: [_buildVideoList(), _buildDetailView(info)],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildVideoList() {
    return ListView.builder(
      itemCount: _videoList.length,
      itemBuilder: (ctx, idx) {
        final item = _videoList[idx] as Map<String, dynamic>;
        final nodes = item['nodes'] as List<dynamic>?;
        if (nodes != null && nodes.isNotEmpty) {
          return ExpansionTile(
            title: Text(item['NAME'] ?? ''),
            children:
                nodes
                    .asMap()
                    .entries
                    .map(
                      (e) => _buildVideoItem(
                        e.value as Map<String, dynamic>,
                        true,
                        idx,
                        e.key,
                      ),
                    )
                    .toList(),
          );
        }
        return _buildVideoItem(item, false, idx, 0);
      },
    );
  }

  Widget _buildVideoItem(
    Map<String, dynamic> m,
    bool hasNodes,
    int fi,
    int ni,
  ) {
    return Container(
      color: Colors.white,
      padding: const EdgeInsets.all(20),
      child: Column(
        children: [
          Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              const Icon(Icons.file_copy_rounded, color: Colors.grey, size: 20),
              Expanded(
                child: Text(
                  m['NAME'] ?? '',
                  style: const TextStyle(fontSize: 14),
                ),
              ),
            ],
          ),
          const SizedBox(height: 10),
          GestureDetector(
            onTap: () => _onVideoTap(m, hasNodes, fi, ni),
            child: Container(
              height: 80,
              padding: const EdgeInsets.symmetric(vertical: 10, horizontal: 8),
              decoration: BoxDecoration(
                color: const Color(0xFFFAFAFA),
                borderRadius: BorderRadius.circular(5),
              ),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Expanded(
                    child: Text(
                      m['COURSEWARENAME'] ?? '',
                      style: const TextStyle(fontSize: 14),
                    ),
                  ),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        "进度：${m['percent']}",
                        style: const TextStyle(color: Colors.blue),
                      ),
                      if (m['IS_VIDEO'] == 0) ...[
                        Text(secondsCount(m['VIDEOTIME'])),
                        const Icon(Icons.play_circle, color: Colors.blue),
                      ],
                      CustomButton(
                        onPressed:
                            () => pushPage(
                              StudyPractisePage(m['VIDEOCOURSEWARE_ID']),
                              context,
                            ),
                        text: "课后练习",
                        backgroundColor: Colors.blue,
                        height: 30,
                        textStyle: const TextStyle(
                          fontSize: 12,
                          color: Colors.white,
                        ),
                        padding: const EdgeInsets.symmetric(
                          vertical: 2,
                          horizontal: 12,
                        ),
                        borderRadius: 15,
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildDetailView(Map info) {
    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            info['CURRICULUMINTRODUCE'] ?? '',
            style: const TextStyle(fontSize: 16),
          ),
          const SizedBox(height: 16),
          if (info['COVERPATH'] != null)
            Image.network(ApiService.baseImgPath + info['COVERPATH']),
        ],
      ),
    );
  }
}