import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'dart:async'; // Timer를 사용하기 위해 추가
import 'package:intl/intl.dart';

// import 'package:flutter_native_timezone/flutter_native_timezone.dart'; // 주석 처리된 상태 유지
// import '../plan_page.dart'; // HomePage는 이제 PlanPage를 직접 포함하지 않음

// CaseStudyPlan 클래스 (변경 없음)
class CaseStudyPlan {
  final String planId;
  final String planTitle;
  final String planTeacher;
  final String thumbnail;

  CaseStudyPlan({
    required this.planId,
    required this.planTitle,
    required this.planTeacher,
    required this.thumbnail,
  });

  factory CaseStudyPlan.fromJson(Map<String, dynamic> json) {
    return CaseStudyPlan(
      planId: json['planId'] ?? '아이디 없음',
      planTitle: json['planTitle'] ?? '제목 없음',
      planTeacher: json['planTeacher'] ?? '선생님 정보 없음',
      thumbnail: json['thumbnail'] ?? '',
    );
  }
}

// 새로운 추천 플랜 모델 (변경 없음)
class RecommendPlan {
  final String planId;
  final String planName;
  final String thumbnail;

  RecommendPlan({
    required this.planId,
    required this.planName,
    required this.thumbnail,
  });

  factory RecommendPlan.fromJson(Map<String, dynamic> json) {
    return RecommendPlan(
      planId: json['plan id'] ?? 'ID 없음',
      planName: json['plane name'] ?? '이름 없음',
      thumbnail: json['thumbnail'] ?? '',
    );
  }
}

// *** 추가: 콜백 함수의 타입을 정의 ***
typedef OnNavigateToPage = void Function(int pageIndex);

class HomePage extends StatefulWidget {
  // *** 추가: 콜백 함수를 받을 프로퍼티 ***
  final OnNavigateToPage onNavigateToPlanTab;

  const HomePage({
    super.key,
    required this.onNavigateToPlanTab, // *** 생성자에서 콜백 함수를 받도록 수정 ***
  });

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  late Future<List<CaseStudyPlan>> _caseStudyPlans;
  DateTime _currentTime = DateTime.now();
  String _currentTimeZone = 'Loading timezone...';
  late Stream<DateTime> _clockStream;

  // int _selectedIndex = 0; // *** HomePage 자체에서 선택된 인덱스를 관리할 필요가 없어짐 ***

  // --- 추천 클래스 관련 상태 변수 ---
  List<RecommendPlan> _recommendPlans = [];
  int _currentRecommendIndex = 0;
  Timer? _recommendTimer;
  bool _isLoadingRecommends = true;
  bool _hasRecommendError = false;
  String _recommendErrorText = '';

  // --- 추천 클래스 관련 상태 변수 끝 ---

  // *** _buildPageContents() 메소드는 HomePage에서 더 이상 사용되지 않음 ***
  // List<Widget> _buildPageContents() {
  //   return [
  //     _buildHomeContent(context), // context 전달 필요
  //     // const PlanPage(), // HomePage가 PlanPage를 직접 포함하지 않음
  //   ];
  // }

  @override
  void initState() {
    super.initState();
    _caseStudyPlans = _fetchCaseStudyPlans();
    _fetchTimezone();
    _clockStream = Stream.periodic(const Duration(seconds: 1), (_) {
      return DateTime.now();
    });
    _currentTime = DateTime.now();
    _fetchRecommendPlans(); // 추천 클래스 데이터 로드
  }

  @override
  void dispose() {
    _recommendTimer?.cancel();
    super.dispose();
  }

  Future<List<CaseStudyPlan>> _fetchCaseStudyPlans() async {
    final response = await http
        .get(Uri.parse('https://helloworld2-ad2uqhckxq-uc.a.run.app'));
    if (response.statusCode == 200) {
      final Map<String, dynamic> decodedJson = json.decode(response.body);
      if (decodedJson.containsKey('data') && decodedJson['data'] is List) {
        final List<dynamic> plansJson = decodedJson['data'];
        return plansJson
            .map((jsonItem) =>
            CaseStudyPlan.fromJson(jsonItem as Map<String, dynamic>))
            .toList();
      } else {
        throw Exception(
            'Invalid data format: "data" field is missing or not a list.');
      }
    } else {
      throw Exception(
          'Failed to load case study plans. Status Code: ${response
              .statusCode}');
    }
  }

  Future<void> _fetchTimezone() async {
    try {
      final String timeZone = DateTime
          .now()
          .timeZoneName;
      if (mounted) {
        setState(() {
          _currentTimeZone = timeZone;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _currentTimeZone = 'Failed to get timezone.';
        });
      }
      print('Could not get timezone: $e');
    }
  }

  Future<void> _fetchRecommendPlans() async {
    if (!mounted) return;
    setState(() {
      _isLoadingRecommends = true;
      _hasRecommendError = false;
      _recommendErrorText = '';
    });
    try {
      final response = await http
          .get(Uri.parse('https://helloworld3-ad2uqhckxq-uc.a.run.app'));
      if (!mounted) return;

      if (response.statusCode == 200) {
        final Map<String, dynamic> decodedJson = json.decode(response.body);
        if (decodedJson.containsKey('data') && decodedJson['data'] is List) {
          final List<dynamic> plansJson = decodedJson['data'];
          setState(() {
            _recommendPlans = plansJson
                .map((jsonItem) =>
                RecommendPlan.fromJson(jsonItem as Map<String, dynamic>))
                .toList();
            _isLoadingRecommends = false;
            if (_recommendPlans.isNotEmpty) {
              _currentRecommendIndex = 0;
              _startRecommendTimer();
            }
          });
        } else {
          throw Exception(
              'Invalid data format for recommend plans: "data" field is missing or not a list.');
        }
      } else {
        throw Exception(
            'Failed to load recommend plans. Status Code: ${response
                .statusCode}');
      }
    } catch (e) {
      print('Error fetching recommend plans: $e');
      if (mounted) {
        setState(() {
          _isLoadingRecommends = false;
          _hasRecommendError = true;
          _recommendErrorText = e.toString();
        });
      }
    }
  }

  void _startRecommendTimer() {
    _recommendTimer?.cancel();
    if (_recommendPlans.isEmpty || !mounted) return;

    _recommendTimer = Timer.periodic(const Duration(seconds: 10), (timer) {
      if (!mounted || _recommendPlans.isEmpty) {
        timer.cancel();
        return;
      }
      setState(() {
        _currentRecommendIndex =
            (_currentRecommendIndex + 1) % _recommendPlans.length;
      });
    });
  }

  Widget _buildLocalTimeBar() {
    return StreamBuilder<DateTime>(
      stream: _clockStream,
      initialData: _currentTime,
      builder: (context, snapshot) {
        final DateTime displayTime = snapshot.data ?? DateTime.now();
        final String formattedDate = DateFormat.yMMMMd().format(displayTime);
        final String formattedTime = DateFormat.jms().format(displayTime);
        return Container(
          width: double.infinity,
          padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
          color: Theme
              .of(context)
              .primaryColor
              .withOpacity(0.1),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              const Text('Your Local Time', style: TextStyle(
                  fontWeight: FontWeight.bold, fontSize: 16.0)),
              const SizedBox(height: 6.0),
              Text('$formattedDate, $formattedTime', style: const TextStyle(
                  fontSize: 18.0, fontWeight: FontWeight.w500)),
              const SizedBox(height: 4.0),
              Text('Timezone: $_currentTimeZone',
                  style: TextStyle(fontSize: 13.0, color: Colors.grey[700])),
            ],
          ),
        );
      },
    );
  }

  Widget _buildRecommendSection() {
    if (_isLoadingRecommends) {
      return const Padding(
        padding: EdgeInsets.symmetric(vertical: 20.0),
        child: Center(child: CircularProgressIndicator()),
      );
    }

    if (_hasRecommendError) {
      return Padding(
        padding: const EdgeInsets.symmetric(vertical: 20.0, horizontal: 16.0),
        child: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const Icon(Icons.error_outline, color: Colors.red, size: 40),
              const SizedBox(height: 8),
              Text(
                'Failed to load recommendations.\n$_recommendErrorText',
                textAlign: TextAlign.center,
                style: const TextStyle(color: Colors.redAccent),
              ),
              const SizedBox(height: 8),
              ElevatedButton.icon(
                icon: const Icon(Icons.refresh),
                label: const Text('Retry'),
                onPressed: _fetchRecommendPlans,
              )
            ],
          ),
        ),
      );
    }

    if (_recommendPlans.isEmpty) {
      return const Padding(
        padding: EdgeInsets.symmetric(vertical: 20.0),
        child: Center(
            child: Text('No recommendations available at the moment.')),
      );
    }

    final currentPlan = _recommendPlans[_currentRecommendIndex];

    return Container(
      margin: const EdgeInsets.fromLTRB(16.0, 12.0, 16.0, 16.0),
      padding: const EdgeInsets.all(12.0),
      decoration: BoxDecoration(
        color: Theme
            .of(context)
            .cardColor,
        borderRadius: BorderRadius.circular(12.0),
        boxShadow: [
          BoxShadow(
            color: Colors.grey.withOpacity(0.2),
            spreadRadius: 1,
            blurRadius: 4,
            offset: const Offset(0, 2),
          ),
        ],
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            '✨ Recommend Classes',
            style: Theme
                .of(context)
                .textTheme
                .titleLarge
                ?.copyWith(fontWeight: FontWeight.bold),
          ),
          const SizedBox(height: 12.0),
          AspectRatio(
            aspectRatio: 16 / 9,
            child: ClipRRect(
              borderRadius: BorderRadius.circular(8.0),
              child: currentPlan.thumbnail.isNotEmpty
                  ? Image.network(
                currentPlan.thumbnail,
                fit: BoxFit.cover,
                loadingBuilder: (BuildContext context, Widget child,
                    ImageChunkEvent? loadingProgress) {
                  if (loadingProgress == null) return child;
                  return Container(
                    color: Colors.grey[200],
                    child: Center(
                      child: CircularProgressIndicator(
                        value: loadingProgress.expectedTotalBytes != null
                            ? loadingProgress.cumulativeBytesLoaded /
                            loadingProgress.expectedTotalBytes!
                            : null,
                      ),
                    ),
                  );
                },
                errorBuilder: (BuildContext context, Object exception,
                    StackTrace? stackTrace) {
                  return Container(
                    color: Colors.grey[200],
                    child: const Center(child: Icon(
                        Icons.broken_image, color: Colors.grey, size: 50)),
                  );
                },
              )
                  : Container(
                color: Colors.grey[200],
                child: const Center(child: Text('No Image Available',
                    style: TextStyle(color: Colors.grey))),
              ),
            ),
          ),
          const SizedBox(height: 10.0),
          Text(
            currentPlan.planName,
            style: Theme
                .of(context)
                .textTheme
                .titleMedium
                ?.copyWith(fontWeight: FontWeight.w500),
            maxLines: 2,
            overflow: TextOverflow.ellipsis,
          ),
        ],
      ),
    );
  }

  Widget _buildHomeContent(BuildContext context) {
    // *** BuildContext를 받도록 수정 ***
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        _buildLocalTimeBar(),
        Padding(
          padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceEvenly,
            children: <Widget>[
              Expanded(
                child: ElevatedButton.icon(
                  icon: const Icon(Icons.add_circle_outline, size: 20),
                  label: const Text(
                      'Book Class', style: TextStyle(fontSize: 14)),
                  onPressed: () {
                    ScaffoldMessenger
                        .of(context)
                        .showSnackBar( // *** context 사용 ***
                      const SnackBar(content: Text('Book Class 버튼 기능 구현 예정')),
                    );
                  },
                  style: ElevatedButton.styleFrom(
                    padding: const EdgeInsets.symmetric(vertical: 12.0),
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(8.0),
                    ),
                  ),
                ),
              ),
              const SizedBox(width: 12.0),
              Expanded(
                child: ElevatedButton.icon(
                  icon: const Icon(Icons.schedule, size: 20),
                  label: const Text('Schedule', style: TextStyle(fontSize: 14)),
                  onPressed: () {
                    ScaffoldMessenger
                        .of(context)
                        .showSnackBar( // *** context 사용 ***
                      const SnackBar(content: Text('Schedule 버튼 기능 구현 예정')),
                    );
                  },
                  style: ElevatedButton.styleFrom(
                    padding: const EdgeInsets.symmetric(vertical: 12.0),
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(8.0),
                    ),
                  ),
                ),
              ),
            ],
          ),
        ),
        const Padding(
          padding: EdgeInsets.fromLTRB(16.0, 16.0, 16.0, 8.0),
          child: Text('Upcoming Classes',
              style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold)),
        ),
        Expanded(
          child: FutureBuilder<List<CaseStudyPlan>>(
            future: _caseStudyPlans,
            builder: (context, snapshot) {
              if (snapshot.connectionState == ConnectionState.waiting) {
                return const Center(child: CircularProgressIndicator());
              } else if (snapshot.hasError) {
                return Center(child: Padding(
                  padding: const EdgeInsets.all(16.0),
                  child: Text(
                      'Error loading upcoming classes: ${snapshot.error}',
                      textAlign: TextAlign.center),
                ));
              } else if (!snapshot.hasData || snapshot.data!.isEmpty) {
                return const Center(
                    child: Text('No upcoming classes available.'));
              } else {
                final plans = snapshot.data!;
                return ListView.builder(
                  padding: const EdgeInsets.only(top: 8.0),
                  itemCount: plans.length,
                  itemBuilder: (context, index) {
                    final plan = plans[index];
                    return InkWell(
                      onTap: () {
                        // *** 부모 위젯(MyHomePage)에게 Plan 탭으로 이동하라고 알림 ***
                        // *** PlanPage가 _widgetOptions 리스트에서 두 번째(인덱스 1)라고 가정 ***
                        widget.onNavigateToPlanTab(1); // *** 전달받은 콜백 호출 ***
                      },
                      child: Card(
                        margin: const EdgeInsets.symmetric(
                            vertical: 6.0, horizontal: 16.0),
                        elevation: 2.0,
                        shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(10.0)),
                        child: Padding(
                          padding: const EdgeInsets.all(12.0),
                          child: Column(
                            crossAxisAlignment: CrossAxisAlignment.start,
                            children: <Widget>[
                              Row(
                                mainAxisAlignment: MainAxisAlignment
                                    .spaceBetween,
                                crossAxisAlignment: CrossAxisAlignment.start,
                                children: <Widget>[
                                  Expanded(
                                    child: Text(
                                      plan.planTitle,
                                      style: Theme
                                          .of(context)
                                          .textTheme
                                          .titleMedium
                                          ?.copyWith(
                                          fontWeight: FontWeight.bold),
                                      overflow: TextOverflow.ellipsis,
                                      maxLines: 2,
                                    ),
                                  ),
                                  const SizedBox(width: 8.0),
                                  Text(
                                    plan.planTeacher,
                                    style: Theme
                                        .of(context)
                                        .textTheme
                                        .bodySmall
                                        ?.copyWith(color: Colors.grey[600]),
                                  ),
                                ],
                              ),
                              const SizedBox(height: 8.0),
                              if (plan.thumbnail.isNotEmpty)
                                ClipRRect(
                                  borderRadius: BorderRadius.circular(8.0),
                                  child: Image.network(
                                    plan.thumbnail,
                                    height: 150,
                                    width: double.infinity,
                                    fit: BoxFit.cover,
                                    loadingBuilder: (BuildContext context,
                                        Widget child,
                                        ImageChunkEvent? loadingProgress) {
                                      if (loadingProgress == null) return child;
                                      return Container(
                                        height: 150,
                                        color: Colors.grey[200],
                                        child: Center(
                                          child: CircularProgressIndicator(
                                            value: loadingProgress
                                                .expectedTotalBytes != null
                                                ? loadingProgress
                                                .cumulativeBytesLoaded /
                                                loadingProgress
                                                    .expectedTotalBytes!
                                                : null,
                                          ),
                                        ),
                                      );
                                    },
                                    errorBuilder: (BuildContext context,
                                        Object exception,
                                        StackTrace? stackTrace) {
                                      return Container(height: 150,
                                          color: Colors.grey[200],
                                          child: const Center(child: Icon(
                                              Icons.broken_image,
                                              color: Colors.grey, size: 50)));
                                    },
                                  ),
                                )
                              else
                                Container(height: 150,
                                    color: Colors.grey[200],
                                    child: const Center(child: Text('No Image',
                                        style: TextStyle(color: Colors.grey)))),
                            ],
                          ),
                        ),
                      ),
                    );
                  },
                );
              }
            },
          ),
        ),
        _buildRecommendSection(),
      ],
    );
  }

  // *** _onItemTapped 메소드는 HomePage에서 더 이상 사용되지 않음 (상위 위젯에서 관리) ***
  // void _onItemTapped(int index) {
  //   setState(() {
  //     _selectedIndex = index;
  //     if (index == 0 && _recommendPlans.isNotEmpty && (_recommendTimer == null || !_recommendTimer!.isActive)) {
  //       _startRecommendTimer();
  //     } else if (index != 0) {
  //       _recommendTimer?.cancel();
  //     }
  //   });
  // }

  @override
  Widget build(BuildContext context) {
    // *** HomePage는 이제 Scaffold나 BottomNavigationBar를 직접 빌드하지 않음 ***
    // *** _buildHomeContent가 context를 사용하므로 전달 ***
    return _buildHomeContent(context);
  }
}