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:csp2/common/widgets/upcoming_class_card.dart';
import 'package:csp2/common/widgets/course_card.dart';
import 'package:csp2/course.dart'; // Course 클래스 import
import '../plan_page.dart'; // PlanPage import

// 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['casestudy lesson id'] ?? '아이디 없음',
      planTitle: json['course_name'] ?? '제목 없음',
      planTeacher: json['course_description'] ?? '선생님',
      thumbnail: json['course_thumbnail'] ?? '',
    );
  }
}

// 새로운 추천 플랜 모델
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'] ?? '',
    );
  }
}

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;
  late Future<List<Course>> _newCoursesFuture; // New: Future for new courses
  DateTime _currentTime = DateTime.now();
  String _currentTimeZone = 'Loading timezone...';
  late Stream<DateTime> _clockStream;

  // --- 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 ---

  List<Widget> _buildPageContents() {
    return [
      _buildHomeContent(),
      const PlanPage(),
    ];
  }

  @override
  void initState() {
    super.initState();
    _caseStudyPlans = _fetchCaseStudyPlans();

    _newCoursesFuture = _fetchNewCourses(); // Initialize new courses future
    _fetchTimezone();
    _clockStream = Stream.periodic(const Duration(seconds: 1), (_) {
      return DateTime.now();
    });
    _currentTime = DateTime.now();

    // --- 추천 클래스 데이터 로드 및 타이머 시작 ---
    _fetchRecommendPlans();
    // --- 추천 클래스 데이터 로드 및 타이머 시작 끝 ---
  }

  @override
  void dispose() {
    _recommendTimer?.cancel(); // 위젯 제거 시 타이머 취소
    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}');
    }
  }

  // New: Fetch new courses from API
  Future<List<Course>> _fetchNewCourses() async {
    final response = await http.get(Uri.parse('https://helloworld5-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> coursesJson = decodedJson['data'];
        return coursesJson
            .map((jsonItem) => Course.fromJson(jsonItem as Map<String, dynamic>))
            .toList();
      } else {
        throw Exception('Invalid data format for new courses: "data" field is missing or not a list.');
      }
    } else {
      throw Exception('Failed to load new courses. 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.';
        });
      }
    }
  }

  // --- 추천 클래스 데이터 가져오는 함수 ---
  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; // 데이터 로드 후 인덱스 초기화
              _startRecommendTimer(); // 데이터 로드 후 타이머 시작
            }
          });
        } 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) {
      if (mounted) {
        setState(() {
          _isLoadingRecommends = false;
          _hasRecommendError = true;
          _recommendErrorText = e.toString();
        });
      }
    }
  }
  // --- 추천 클래스 데이터 가져오는 함수 끝 ---

  // --- 추천 클래스 순환 타이머 시작 함수 ---
  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;
      });
    });
  }
  // --- 추천 클래스 순환 타이머 시작 함수 끝 ---

  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(
          padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
          decoration: BoxDecoration(
            color: Theme.of(context).primaryColor.withAlpha(25),
            borderRadius: BorderRadius.circular(8.0),
          ),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center, // 세로 중앙 정렬
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              const Text('Your Local Time', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 16.0)),
              const SizedBox(height: 6.0),
              Text('$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 _buildButtons() {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center, // 세로 중앙 정렬
      crossAxisAlignment: CrossAxisAlignment.stretch, // 버튼이 가로로 꽉 차게 설정
      children: [
        Expanded( // 버튼이 할당된 세로 공간을 모두 차지하도록 설정
          child: ElevatedButton.icon(
            icon: const Icon(Icons.add_circle_outline, size: 20),
            label: const Text('Book Class', style: TextStyle(fontSize: 20)),
            onPressed: () {
              ScaffoldMessenger.of(context).showSnackBar(
                const SnackBar(content: Text('Book Class 버튼 기능 구현 예정')),
              );
            },
            style: ElevatedButton.styleFrom(
              backgroundColor: Colors.blue, // 배경색을 파란색으로 설정
              foregroundColor: Colors.white, // 글자색을 흰색으로 설정
              padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(8.0),
              ),
            ),
          ),
        ),
        // const SizedBox(height: 8.0),
        // ElevatedButton.icon(
        //   icon: const Icon(Icons.schedule, size: 20),
        //   label: const Text('Schedule', style: TextStyle(fontSize: 14)),
        //   onPressed: () {
        //     ScaffoldMessenger.of(context).showSnackBar(
        //       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),
        //     ),
        //   ),
        // ),
      ],
    );
  }

  Widget _buildHomeContent() {
    return SingleChildScrollView(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: <Widget>[
          Padding(
            padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
            child: IntrinsicHeight(
              child: Row(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                children: [
                  Expanded(
                    flex: 1,
                    child: _buildLocalTimeBar(),
                  ),
                  const SizedBox(width: 12.0),
                  Expanded(
                    flex: 1,
                    child: _buildButtons(),
                  ),
                ],
              ),
            ),
          ),
          const Padding(
            padding: EdgeInsets.fromLTRB(16.0, 16.0, 16.0, 8.0), // vertical을 위아래 다르게 조정
            child: Text('Upcoming Study', style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold)),
          ),
          SizedBox(
            height: 200, // 가로 리스트의 높이를 줄입니다.
            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(
                    scrollDirection: Axis.horizontal, // 가로 스크롤로 변경
                    padding: const EdgeInsets.only(left: 10.0, right: 5.0, top: 8.0, bottom: 5.0),
                    itemCount: plans.length,
                    itemBuilder: (context, index) {
                      final plan = plans[index];
                      return Align(
                        alignment: Alignment.topCenter, // 항목을 상단 중앙에 정렬
                        child: UpcomingClassCard(
                          plan: plan,
                          onTap: () {
                            widget.onNavigateToPlanTab(1);
                          },
                        ),
                      );
                    },
                  );
                }
              },
            ),
          ),
          // --- ▼▼▼ Find Your New Course 섹션 ▼▼▼ ---
          const Padding(
            padding: EdgeInsets.fromLTRB(16.0, 16.0, 16.0, 8.0),
            child: Text('Find Your New Course', style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold)),
          ),
          SizedBox(
            height: 180,
            child: FutureBuilder<List<Course>>(
              future: _newCoursesFuture,
              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 new courses: ${snapshot.error}', textAlign: TextAlign.center),
                  ));
                } else if (!snapshot.hasData || snapshot.data!.isEmpty) {
                  return const Center(child: Text('No new courses available.'));
                } else {
                  final courses = snapshot.data!;
                  return ListView.builder(
                    scrollDirection: Axis.horizontal,
                    padding: const EdgeInsets.only(left: 10.0, right: 10.0, top: 5.0, bottom: 5.0),
                    itemCount: courses.length,
                    itemBuilder: (context, index) {
                      final course = courses[index];
                      return CourseCard(course: course);
                    },
                  );
                }
              },
            ),
          ),
          // --- ▲▲▲ Find Your New Course 섹션 끝 ▲▲▲ ---
          // --- ▼▼▼ 추천 클래스 섹션 호출 ▼▼▼ ---
          _buildRecommendSection(),
          // --- ▲▲▲ 추천 클래스 섹션 호출 끝 ▲▲▲ ---
          const Padding(
            padding: EdgeInsets.fromLTRB(16.0, 16.0, 16.0, 8.0),
            child: Text('Trending On New Study', style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold)),
          ),
          SizedBox(
            height: 200, // 가로 리스트의 높이를 줄입니다.
            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(
                    scrollDirection: Axis.horizontal, // 가로 스크롤로 변경
                    padding: const EdgeInsets.only(left: 10.0, right: 5.0, top: 8.0, bottom: 5.0),
                    itemCount: plans.length,
                    itemBuilder: (context, index) {
                      final plan = plans[index];
                      return Align(
                        alignment: Alignment.topCenter, // 항목을 상단 중앙에 정렬
                        child: UpcomingClassCard(
                          plan: plan,
                          onTap: () {
                            widget.onNavigateToPlanTab(1);
                          },
                        ),
                      );
                    },
                  );
                }
              },
            ),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final List<Widget> pageContents = _buildPageContents();

    return Scaffold(
      // appBar: AppBar( // AppBar 주석 처리됨 (기존 코드에서)
      //   title: Text(_selectedIndex == 0 ? 'Home' : 'Plan Page'),
      // ),
        body: IndexedStack( // AppBar가 없으므로 SafeArea로 감싸는 것을 고려해볼 수 있습니다.
          index: 0,
          children: pageContents,
        )
    );
  }
  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(0.0, 12.0, 0.0, 0.0), // 하단 마진 추가
      // padding: const EdgeInsets.all(12.0),
      decoration: BoxDecoration(
        color: Theme.of(context).cardColor, // 카드 색상 사용
        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: [
          AspectRatio(
            aspectRatio: 6 / 1,
            child: ClipRRect(
              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( // 로딩 중 배경색 및 인디케이터 중앙 정렬 개선
                    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))),
              ),
            ),
          )],
      ),
    );
  }
}