import 'package:flutter/material.dart';
import 'package:sudoku_app/models/game_rank_dto.dart';
import 'package:sudoku_app/services/puzzle_service.dart';

class RankingScreen extends StatefulWidget {
  // 🔽 [추가] 홈 화면에서 전달받을 초기 난이도 이름
  final String? initialDifficultyName;

  const RankingScreen({
    super.key,
    this.initialDifficultyName, // 👈 생성자에 추가
  });

  @override
  State<RankingScreen> createState() => _RankingScreenState();
}

class _RankingScreenState extends State<RankingScreen> {
  final PuzzleService _puzzleService = PuzzleService();
  late Future<List<GameRankDto>> _rankingFuture;

  // 8단계 난이도에 맞는 Context ID 맵
  final Map<String, String> difficultyContexts = {
    "입문 (4x4)": "SUDOKU_4x4_L1",
    "초급 (4x4)": "SUDOKU_4x4_L2",
    "쉬움 (9x9)": "SUDOKU_9x9_L3",
    "중급 (9x9)": "SUDOKU_9x9_L4",
    "어려움 (9x9)": "SUDOKU_9x9_L5",
    "전문가 (16x16)": "SUDOKU_16x16_L6",
    "마스터 (16x16)": "SUDOKU_16x16_L7",
    "지옥 (16x16)": "SUDOKU_16x16_L8",
  };
  late String _selectedDifficulty;

  @override
  void initState() {
    super.initState();
    // 🔽 [수정]
    // 1. HomeScreen에서 전달받은 값이 있는지 확인
    String defaultDifficulty = widget.initialDifficultyName ?? "중급 (9x9)";

    // 2. (안전장치) 전달받은 값이 맵에 없으면(예: 향후 변경) 기본값 사용
    if (!difficultyContexts.containsKey(defaultDifficulty)) {
      defaultDifficulty = "중급 (9x9)";
    }
    
    // 3. 랭킹 조회
    _fetchRanksForDifficulty(defaultDifficulty);
  }

  void _fetchRanksForDifficulty(String difficultyName) {
    setState(() {
      _selectedDifficulty = difficultyName;
      _rankingFuture = _puzzleService.fetchRanks('SUDOKU', difficultyContexts[_selectedDifficulty]);
    });
  }

  // 시간(초)을 'mm:ss' 형식으로 변환
  String _formatTime(int seconds) {
    final min = (seconds ~/ 60).toString().padLeft(2, '0');
    final sec = (seconds % 60).toString().padLeft(2, '0');
    return '$min:$sec';
  }

  // (5 - score)로 저장된 값을 -> "SCORE: 5"로 변환
  String _formatScore(int? storedScore) {
    int score = 5 - (storedScore ?? 5);
    return 'SCORE: $score';
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('스도쿠 랭킹')),
      body: Column(
        children: [
          // 1. 난이도 선택 Dropdown
          Padding(
            padding: const EdgeInsets.all(16.0),
            child: DropdownButton<String>(
              value: _selectedDifficulty, // 👈 initState에서 설정된 값으로 시작
              isExpanded: true,
              items: difficultyContexts.keys.map((String difficultyName) {
                return DropdownMenuItem<String>(
                  value: difficultyName,
                  child: Text(difficultyName),
                );
              }).toList(),
              onChanged: (String? newValue) {
                if (newValue != null) {
                  _fetchRanksForDifficulty(newValue);
                }
              },
            ),
          ),
          // 2. 랭킹 리스트
          Expanded(
            child: FutureBuilder<List<GameRankDto>>(
              future: _rankingFuture,
              builder: (context, snapshot) {
                if (snapshot.connectionState == ConnectionState.waiting) {
                  return const Center(child: CircularProgressIndicator());
                }
                if (snapshot.hasError) {
                  return Center(child: Text('랭킹 로딩 실패: ${snapshot.error}'));
                }
                if (!snapshot.hasData || snapshot.data!.isEmpty) {
                  return const Center(child: Text('등록된 랭킹이 없습니다.'));
                }

                final ranks = snapshot.data!;
                return ListView.builder(
                  itemCount: ranks.length,
                  itemBuilder: (context, index) {
                    final rank = ranks[index];
                    return ListTile(
                      leading: Text(
                        '${index + 1}.',
                        style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
                      ),
                      title: Text(rank.playerName, style: const TextStyle(fontSize: 18)),
                      trailing: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        crossAxisAlignment: CrossAxisAlignment.end,
                        children: [
                          Text(
                            _formatTime(rank.primaryScore),
                            style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold, color: Colors.blue),
                          ),
                          Text(
                            _formatScore(rank.secondaryScore),
                            style: const TextStyle(fontSize: 12, color: Colors.grey),
                          ),
                        ],
                      ),
                    );
                  },
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}