import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:geolocator/geolocator.dart';
import '../../../core/constants/app_colors.dart';
import '../../../core/constants/app_typography.dart';
import '../../../domain/entities/weather_info.dart';
import '../../../domain/entities/restaurant.dart';
import '../../providers/restaurant_provider.dart';
import '../../providers/weather_provider.dart';
import '../../providers/location_provider.dart';
import '../../providers/recommendation_provider.dart';
import 'widgets/recommendation_result_dialog.dart';

class RandomSelectionScreen extends ConsumerStatefulWidget {
  const RandomSelectionScreen({super.key});

  @override
  ConsumerState<RandomSelectionScreen> createState() => _RandomSelectionScreenState();
}

class _RandomSelectionScreenState extends ConsumerState<RandomSelectionScreen> {
  double _distanceValue = 500;
  final List<String> _selectedCategories = [];
  
  @override
  Widget build(BuildContext context) {
    final isDark = Theme.of(context).brightness == Brightness.dark;
    
    return Scaffold(
      backgroundColor: isDark ? AppColors.darkBackground : AppColors.lightBackground,
      appBar: AppBar(
        title: const Text('오늘 뭐 먹Z?'),
        backgroundColor: isDark ? AppColors.darkPrimary : AppColors.lightPrimary,
        foregroundColor: Colors.white,
        elevation: 0,
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            // 맛집 리스트 현황 카드
            Card(
              color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
              elevation: 2,
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(12),
              ),
              child: Padding(
                padding: const EdgeInsets.all(20),
                child: Column(
                  children: [
                    const Icon(
                      Icons.restaurant,
                      size: 48,
                      color: AppColors.lightPrimary,
                    ),
                    const SizedBox(height: 12),
                    Consumer(
                      builder: (context, ref, child) {
                        final restaurantsAsync = ref.watch(restaurantListProvider);
                        return restaurantsAsync.when(
                          data: (restaurants) => Text(
                            '${restaurants.length}개',
                            style: AppTypography.heading1(isDark).copyWith(
                              color: AppColors.lightPrimary,
                            ),
                          ),
                          loading: () => const CircularProgressIndicator(
                            color: AppColors.lightPrimary,
                          ),
                          error: (_, __) => Text(
                            '0개',
                            style: AppTypography.heading1(isDark).copyWith(
                              color: AppColors.lightPrimary,
                            ),
                          ),
                        );
                      },
                    ),
                    Text(
                      '등록된 맛집',
                      style: AppTypography.body2(isDark),
                    ),
                  ],
                ),
              ),
            ),
            
            const SizedBox(height: 16),
            
            // 날씨 정보 카드
            Card(
              color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
              elevation: 2,
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(12),
              ),
              child: Padding(
                padding: const EdgeInsets.all(16),
                child: Consumer(
                  builder: (context, ref, child) {
                    final weatherAsync = ref.watch(weatherProvider);
                    return weatherAsync.when(
                      data: (weather) => Row(
                        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                        children: [
                          _buildWeatherData('지금', weather.current, isDark),
                          Container(
                            width: 1,
                            height: 50,
                            color: isDark ? AppColors.darkDivider : AppColors.lightDivider,
                          ),
                          _buildWeatherData('1시간 후', weather.nextHour, isDark),
                        ],
                      ),
                      loading: () => const Center(
                        child: CircularProgressIndicator(
                          color: AppColors.lightPrimary,
                        ),
                      ),
                      error: (_, __) => Row(
                        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                        children: [
                          _buildWeatherInfo('지금', Icons.wb_sunny, '맑음', 20, isDark),
                          Container(
                            width: 1,
                            height: 50,
                            color: isDark ? AppColors.darkDivider : AppColors.lightDivider,
                          ),
                          _buildWeatherInfo('1시간 후', Icons.wb_sunny, '맑음', 22, isDark),
                        ],
                      ),
                    );
                  },
                ),
              ),
            ),
            
            const SizedBox(height: 16),
            
            // 거리 설정 카드
            Card(
              color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
              elevation: 2,
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(12),
              ),
              child: Padding(
                padding: const EdgeInsets.all(16),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '최대 거리',
                      style: AppTypography.heading2(isDark),
                    ),
                    const SizedBox(height: 12),
                    Row(
                      children: [
                        Expanded(
                          child: SliderTheme(
                            data: SliderTheme.of(context).copyWith(
                              activeTrackColor: AppColors.lightPrimary,
                              inactiveTrackColor: AppColors.lightPrimary.withValues(alpha: 0.3),
                              thumbColor: AppColors.lightPrimary,
                              trackHeight: 4,
                            ),
                            child: Slider(
                              value: _distanceValue,
                              min: 100,
                              max: 2000,
                              divisions: 19,
                              onChanged: (value) {
                                setState(() => _distanceValue = value);
                              },
                            ),
                          ),
                        ),
                        const SizedBox(width: 12),
                        Text(
                          '${_distanceValue.toInt()}m',
                          style: AppTypography.body1(isDark).copyWith(
                            fontWeight: FontWeight.bold,
                          ),
                        ),
                      ],
                    ),
                    const SizedBox(height: 8),
                    Consumer(
                      builder: (context, ref, child) {
                        final locationAsync = ref.watch(currentLocationProvider);
                        final restaurantsAsync = ref.watch(restaurantListProvider);
                        
                        if (locationAsync.hasValue && restaurantsAsync.hasValue) {
                          final location = locationAsync.value;
                          final restaurants = restaurantsAsync.value;
                          
                          if (location != null && restaurants != null) {
                            final count = _getRestaurantCountInRange(
                              restaurants,
                              location,
                              _distanceValue,
                            );
                            return Text(
                              '$count개 맛집 포함',
                              style: AppTypography.caption(isDark),
                            );
                          }
                        }
                        
                        return Text(
                          '위치 정보를 가져오는 중...',
                          style: AppTypography.caption(isDark),
                        );
                      },
                    ),
                  ],
                ),
              ),
            ),
            
            const SizedBox(height: 16),
            
            // 카테고리 선택 카드
            Card(
              color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
              elevation: 2,
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(12),
              ),
              child: Padding(
                padding: const EdgeInsets.all(16),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '카테고리',
                      style: AppTypography.heading2(isDark),
                    ),
                    const SizedBox(height: 12),
                    Consumer(
                      builder: (context, ref, child) {
                        final categoriesAsync = ref.watch(categoriesProvider);
                        
                        return categoriesAsync.when(
                          data: (categories) => Wrap(
                            spacing: 8,
                            runSpacing: 8,
                            children: categories.isEmpty
                                ? [const Text('카테고리 없음')]
                                : categories.map((category) => _buildCategoryChip(category, isDark)).toList(),
                          ),
                          loading: () => const CircularProgressIndicator(),
                          error: (_, __) => const Text('카테고리를 불러올 수 없습니다'),
                        );
                      },
                    ),
                  ],
                ),
              ),
            ),
            
            const SizedBox(height: 24),
            
            // 추천받기 버튼
            ElevatedButton(
              onPressed: _canRecommend() ? _startRecommendation : null,
              style: ElevatedButton.styleFrom(
                backgroundColor: AppColors.lightPrimary,
                foregroundColor: Colors.white,
                padding: const EdgeInsets.symmetric(vertical: 20),
                shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(12),
                ),
                elevation: 3,
              ),
              child: const Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Icon(Icons.play_arrow, size: 28),
                  SizedBox(width: 8),
                  Text(
                    '광고보고 추천받기',
                    style: TextStyle(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }
  
  Widget _buildWeatherData(String label, WeatherData weatherData, bool isDark) {
    return Column(
      children: [
        Text(label, style: AppTypography.caption(isDark)),
        const SizedBox(height: 8),
        Icon(
          weatherData.isRainy ? Icons.umbrella : Icons.wb_sunny,
          color: weatherData.isRainy ? Colors.blue : Colors.orange,
          size: 32,
        ),
        const SizedBox(height: 4),
        Text(
          '${weatherData.temperature}°C',
          style: AppTypography.body1(isDark).copyWith(
            fontWeight: FontWeight.bold,
          ),
        ),
        Text(
          weatherData.description,
          style: AppTypography.caption(isDark),
        ),
      ],
    );
  }
  
  Widget _buildWeatherInfo(String label, IconData icon, String description, int temperature, bool isDark) {
    return Column(
      children: [
        Text(label, style: AppTypography.caption(isDark)),
        const SizedBox(height: 8),
        Icon(
          icon,
          color: Colors.orange,
          size: 32,
        ),
        const SizedBox(height: 4),
        Text(
          '$temperature°C',
          style: AppTypography.body1(isDark).copyWith(
            fontWeight: FontWeight.bold,
          ),
        ),
        Text(
          description,
          style: AppTypography.caption(isDark),
        ),
      ],
    );
  }
  
  
  Widget _buildCategoryChip(String category, bool isDark) {
    final isSelected = _selectedCategories.contains(category);
    
    return FilterChip(
      label: Text(category),
      selected: isSelected,
      onSelected: (selected) {
        setState(() {
          if (selected) {
            _selectedCategories.add(category);
          } else {
            _selectedCategories.remove(category);
          }
        });
      },
      backgroundColor: isDark ? AppColors.darkSurface : AppColors.lightBackground,
      selectedColor: AppColors.lightPrimary.withValues(alpha: 0.2),
      checkmarkColor: AppColors.lightPrimary,
      labelStyle: TextStyle(
        color: isSelected ? AppColors.lightPrimary : (isDark ? AppColors.darkTextPrimary : AppColors.lightTextPrimary),
      ),
      side: BorderSide(
        color: isSelected ? AppColors.lightPrimary : (isDark ? AppColors.darkDivider : AppColors.lightDivider),
      ),
    );
  }
  
  int _getRestaurantCountInRange(
    List<Restaurant> restaurants,
    Position location,
    double maxDistance,
  ) {
    return restaurants.where((restaurant) {
      final distance = Geolocator.distanceBetween(
        location.latitude,
        location.longitude,
        restaurant.latitude,
        restaurant.longitude,
      );
      return distance <= maxDistance;
    }).length;
  }
  
  bool _canRecommend() {
    final locationAsync = ref.read(currentLocationProvider);
    final restaurantsAsync = ref.read(restaurantListProvider);
    
    if (!locationAsync.hasValue || !restaurantsAsync.hasValue) return false;
    
    final location = locationAsync.value;
    final restaurants = restaurantsAsync.value;
    
    if (location == null || restaurants == null || restaurants.isEmpty) return false;
    
    final count = _getRestaurantCountInRange(restaurants, location, _distanceValue);
    return count > 0;
  }
  
  Future<void> _startRecommendation() async {
    final notifier = ref.read(recommendationNotifierProvider.notifier);
    
    await notifier.getRandomRecommendation(
      maxDistance: _distanceValue,
      selectedCategories: _selectedCategories,
    );
    
    final result = ref.read(recommendationNotifierProvider);
    
    result.whenData((restaurant) {
      if (restaurant != null && mounted) {
        showDialog(
          context: context,
          barrierDismissible: false,
          builder: (context) => RecommendationResultDialog(
            restaurant: restaurant,
            onReroll: () {
              Navigator.pop(context);
              _startRecommendation();
            },
            onConfirmVisit: () {
              Navigator.pop(context);
              ScaffoldMessenger.of(context).showSnackBar(
                const SnackBar(
                  content: Text('맛있게 드세요! 🍴'),
                  backgroundColor: AppColors.lightPrimary,
                ),
              );
            },
          ),
        );
      } else if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(
            content: Text('조건에 맞는 맛집이 없습니다'),
            backgroundColor: AppColors.lightError,
          ),
        );
      }
    });
  }
}