import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'plan_page_detail.dart'; // <<< plan_page_detail.dart 파일을 import 합니다.

// HomePage에서 사용하던 CaseStudyPlan 모델을 PlanPage에서도 사용하거나,
// PlanPage에 필요한 별도의 데이터 모델을 정의할 수 있습니다.
// 여기서는 동일한 모델을 재사용한다고 가정합니다.
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['planTeacher'] ?? '',
      thumbnail: json['course_thumbnail'] ?? '',
    );
  }
}

class PlanPage extends StatefulWidget {
  const PlanPage({super.key});

  @override
  State<PlanPage> createState() => _PlanPageState();
}

class _PlanPageState extends State<PlanPage> {
  late Future<List<CaseStudyPlan>> _planPageData;

  @override
  void initState() {
    super.initState();
    // PlanPage가 처음 생성되거나 화면에 표시될 때 데이터를 가져옵니다.
    _planPageData = _fetchPlanData();
  }

  Future<List<CaseStudyPlan>> _fetchPlanData() async {
    // HomePage와 동일한 API 주소를 사용합니다.
    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 for PlanPage: "data" field is missing or not a list.');
      }
    } else {
      throw Exception(
          'Failed to load data for PlanPage. Status Code: ${response.statusCode}');
    }
  }

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<List<CaseStudyPlan>>(
      future: _planPageData,
      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 PlanPage data: ${snapshot.error}', textAlign: TextAlign.center,
                maxLines: 3,
                overflow: TextOverflow.ellipsis,
              )));
        } else if (!snapshot.hasData || snapshot.data!.isEmpty) {
          return const Center(child: Text('No data available for PlanPage.'));
        } else {
          // 데이터 로딩 성공 시 ListView 표시
          final plans = snapshot.data!;
          return ListView.builder(
            itemCount: plans.length,
            itemBuilder: (context, index) {
              final plan = plans[index];
              return InkWell(
                onTap: () {
                  if (plan.planId == 'ID 없음' || plan.planId.isEmpty) {
                    ScaffoldMessenger.of(context).showSnackBar(
                      const SnackBar(content: Text('유효한 Plan ID가 없어 상세 페이지로 이동할 수 없습니다.')),
                    );
                    return;
                  }
                  Navigator.push(
                    context,
                    MaterialPageRoute(
                      builder: (context) => const PlanPageDetail(),
                      settings: RouteSettings(
                        // <<< Map 형태로 planId와 planTitle을 전달 >>>
                        arguments: {
                          'planId': plan.planId,
                          'planTitle': plan.planTitle,
                        },
                      ),
                    ),
                  );
                },
                child: Card(
                  margin:
                  const EdgeInsets.symmetric(vertical: 8.0, horizontal: 16.0),
                  elevation: 2.0,
                  child: Padding(
                    padding: const EdgeInsets.all(12.0),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: <Widget>[
                        Row(
                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
                          children: <Widget>[
                            Expanded(
                              child: Text(
                                plan.planTitle,
                                style: const TextStyle(
                                    fontSize: 17.0, fontWeight: FontWeight.bold),
                                overflow: TextOverflow.ellipsis,
                                maxLines: 2,
                              ),
                            ),
                            const SizedBox(width: 8.0),
                            Text(
                              plan.planTeacher,
                              style: const TextStyle(
                                  fontSize: 13.0, color: Colors.grey),
                              maxLines: 1,
                              overflow: TextOverflow.ellipsis,
                            ),
                          ],
                        ),
                        const SizedBox(height: 8.0),

                        if (plan.thumbnail.isNotEmpty)
                          ClipRRect(
                            borderRadius: BorderRadius.circular(8.0),
                            child: Image.network(
                              plan.thumbnail,
                              height: 120,
                              width: double.infinity,
                              fit: BoxFit.contain,
                              alignment: Alignment.centerLeft,
                              loadingBuilder: (BuildContext context, Widget child,
                                  ImageChunkEvent? loadingProgress) {
                                if (loadingProgress == null) return child;
                                return Center(
                                  child: CircularProgressIndicator(
                                    value: loadingProgress.expectedTotalBytes !=
                                        null
                                        ? loadingProgress.cumulativeBytesLoaded /
                                        loadingProgress.expectedTotalBytes!
                                        : null,
                                  ),
                                );
                              },
                              errorBuilder: (BuildContext context, Object exception,
                                  StackTrace? stackTrace) {
                                return Container(
                                    height: 140,
                                    color: Colors.grey[200],
                                    child: const Center(
                                        child: Icon(Icons.broken_image,
                                            color: Colors.grey, size: 40)));
                              },
                            ),
                          )
                        else
                          Container(
                              height: 140,
                              color: Colors.grey[200],
                              child: const Center(
                                  child: Text('No Image',
                                      style: TextStyle(color: Colors.grey)))),
                      ],
                    ),
                  ),
                ),
              );
            },
          );
        }
      },
    );
  }
}