import 'package:flutter/material.dart';
import 'package:sudoku_app/models/sudoku_game_dto.dart';
import 'package:sudoku_app/models/sudoku_theme.dart';
import 'package:sudoku_app/screens/game_screen.dart';
import 'package:sudoku_app/screens/ranking_screen.dart';
import 'package:sudoku_app/services/puzzle_service.dart';
import 'package:sudoku_app/services/identity_service.dart'; // 👈 ID 서비스 임포트
import 'package:sudoku_app/widgets/ad_banner_widget.dart';

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

  @override
  State<HomeScreen> createState() => _HomeScreenState();
}

class _HomeScreenState extends State<HomeScreen> {
  // 8단계 난이도
  double _difficultyLevel = 4.0; // 1.0 ~ 8.0 (기본값 Level 4: 중급 9x9)
  final List<String> levelLabels = [
    "입문 (4x4)", "초급 (4x4)", 
    "쉬움 (9x9)", "중급 (9x9)", "어려움 (9x9)",
    "전문가 (16x16)", "마스터 (16x16)", "지옥 (16x16)"
  ];
  
  late String _selectedThemeName;
  bool isLoading = false;
  final PuzzleService _puzzleService = PuzzleService();
  final IdentityService _identityService = IdentityService(); // 👈 ID 서비스 초기화

  @override
  void initState() {
    super.initState();
    _selectedThemeName = AppThemes.random; // 기본 테마 '랜덤'
  }

  Future<void> _startGame() async {
    setState(() { isLoading = true; });

    try {
      // 1. 난이도 값(String) 전달
      final String difficulty = _difficultyLevel.round().toString();
      
      // 2. 서버에서 게임 데이터 가져오기
      final SudokuGameDto gameData = await _puzzleService.startGame(difficulty);
      
      // 3. 로컬에서 앱-고유 ID와 저장된 이름 가져오기
      final String userId = await _identityService.getOrCreateUserId();
      final String? userName = await _identityService.getSavedUserName();

      if (mounted) {
        Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => GameScreen(
              gameData: gameData,
              themeName: _selectedThemeName,
              userId: userId,     // 👈 ID 전달
              userName: userName, // 👈 이름 전달
            ),
          ),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('게임 로딩 실패: $e')),
        );
      }
    } finally {
      if (mounted) {
        setState(() { isLoading = false; });
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('스도쿠 게임')),
      body: LayoutBuilder( // 비율 기반 레이아웃
        builder: (context, constraints) {
          // 너비/높이 비율 변수 (0.6 = 너비가 높이의 60%를 넘지 않도록 함)
          const double maxContentRatio = 0.6;
          final double constrainedWidth = constraints.maxHeight * maxContentRatio;

          return Center(
            child: ConstrainedBox(
              constraints: BoxConstraints(maxWidth: constrainedWidth),
              child: Column(
                children: [
                  Expanded(
                    child: Center(
                      child: Padding(
                        padding: const EdgeInsets.symmetric(horizontal: 20.0),
                        child: Column(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            // 1. 난이도 선택 (8단계)
                            const Text("난이도", style: TextStyle(fontSize: 18)),
                            Text(
                              levelLabels[_difficultyLevel.round() - 1],
                              style: const TextStyle(fontSize: 22, fontWeight: FontWeight.bold, color: Colors.blue),
                            ),
                            Slider(
                              value: _difficultyLevel,
                              min: 1.0, max: 8.0, divisions: 7, // 8단계
                              label: levelLabels[_difficultyLevel.round() - 1],
                              onChanged: (newValue) => setState(() { _difficultyLevel = newValue; }),
                            ),
                            
                            const SizedBox(height: 20),

                            // 2. 테마 선택 (String 기반)
                            const Text("테마", style: TextStyle(fontSize: 18)),
                            DropdownButton<String>(
                              value: _selectedThemeName,
                              items: AppThemes.selectableThemeNames.map((themeName) {
                                return DropdownMenuItem<String>(
                                  value: themeName,
                                  child: Text(themeName, style: const TextStyle(fontSize: 20)),
                                );
                              }).toList(),
                              onChanged: (themeName) {
                                if (themeName != null) {
                                  setState(() { _selectedThemeName = themeName; });
                                }
                              },
                            ),
                            
                            const SizedBox(height: 30),
                            
                            if (isLoading)
                              const CircularProgressIndicator()
                            else
                              ElevatedButton(
                                onPressed: _startGame,
                                style: ElevatedButton.styleFrom(padding: const EdgeInsets.symmetric(horizontal: 40, vertical: 15)),
                                child: const Text('게임 시작', style: TextStyle(fontSize: 18)),
                              ),
                            
                            const SizedBox(height: 10),

                            // "랭킹 보기" 버튼
                            TextButton(
                              onPressed: () {
                                // 현재 슬라이더의 난이도 이름(String)을 가져옴
                                final String currentDifficultyName = levelLabels[_difficultyLevel.round() - 1];
                                
                                Navigator.push(
                                  context,
                                  MaterialPageRoute(
                                    builder: (context) => RankingScreen(
                                      initialDifficultyName: currentDifficultyName,
                                    ),
                                  ),
                                );
                              },
                              child: const Text('랭킹 보기'),
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                  const AdBannerWidget(),
                ],
              ),
            ),
          );
        },
      ),
    );
  }
}