import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:lunchpick/core/constants/app_colors.dart';
import 'package:lunchpick/core/constants/app_typography.dart';
import 'package:lunchpick/presentation/providers/visit_provider.dart';
import 'package:lunchpick/presentation/providers/restaurant_provider.dart';

class VisitStatistics extends ConsumerWidget {
  final DateTime selectedMonth;

  const VisitStatistics({
    super.key,
    required this.selectedMonth,
  });

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final isDark = Theme.of(context).brightness == Brightness.dark;
    
    // 월별 통계
    final monthlyStatsAsync = ref.watch(monthlyVisitStatsProvider((
      year: selectedMonth.year,
      month: selectedMonth.month,
    )));
    
    // 자주 방문한 맛집
    final frequentRestaurantsAsync = ref.watch(frequentRestaurantsProvider);
    
    // 주간 통계
    final weeklyStatsAsync = ref.watch(weeklyVisitStatsProvider);

    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        children: [
          // 이번 달 통계
          _buildMonthlyStats(monthlyStatsAsync, isDark),
          const SizedBox(height: 16),
          
          // 주간 통계 차트
          _buildWeeklyChart(weeklyStatsAsync, isDark),
          const SizedBox(height: 16),
          
          // 자주 방문한 맛집 TOP 3
          _buildFrequentRestaurants(frequentRestaurantsAsync, ref, isDark),
        ],
      ),
    );
  }

  Widget _buildMonthlyStats(AsyncValue<Map<String, int>> statsAsync, bool isDark) {
    return 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(
              '${selectedMonth.month}월 방문 통계',
              style: AppTypography.heading2(isDark),
            ),
            const SizedBox(height: 16),
            statsAsync.when(
              data: (stats) {
                final totalVisits = stats.values.fold(0, (sum, count) => sum + count);
                final categoryCounts = stats.entries
                    .where((e) => !e.key.contains('/'))
                    .toList()
                  ..sort((a, b) => b.value.compareTo(a.value));
                
                return Column(
                  children: [
                    _buildStatItem(
                      icon: Icons.restaurant,
                      label: '총 방문 횟수',
                      value: '$totalVisits회',
                      color: AppColors.lightPrimary,
                      isDark: isDark,
                    ),
                    const SizedBox(height: 12),
                    if (categoryCounts.isNotEmpty) ...[
                      _buildStatItem(
                        icon: Icons.favorite,
                        label: '가장 많이 간 카테고리',
                        value: '${categoryCounts.first.key} (${categoryCounts.first.value}회)',
                        color: AppColors.lightSecondary,
                        isDark: isDark,
                      ),
                    ],
                  ],
                );
              },
              loading: () => const Center(child: CircularProgressIndicator()),
              error: (error, stack) => Text(
                '통계를 불러올 수 없습니다',
                style: AppTypography.body2(isDark),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildWeeklyChart(AsyncValue<Map<String, int>> statsAsync, bool isDark) {
    return 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(
              '최근 7일 방문 현황',
              style: AppTypography.heading2(isDark),
            ),
            const SizedBox(height: 16),
            statsAsync.when(
              data: (stats) {
                final maxCount = stats.values.isEmpty ? 1 : stats.values.reduce((a, b) => a > b ? a : b);
                
                return SizedBox(
                  height: 120,
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                    crossAxisAlignment: CrossAxisAlignment.end,
                    children: stats.entries.map((entry) {
                      final height = maxCount == 0 ? 0.0 : (entry.value / maxCount) * 80;
                      
                      return Column(
                        mainAxisAlignment: MainAxisAlignment.end,
                        children: [
                          Text(
                            entry.value.toString(),
                            style: AppTypography.caption(isDark),
                          ),
                          const SizedBox(height: 4),
                          Container(
                            width: 30,
                            height: height,
                            decoration: BoxDecoration(
                              color: AppColors.lightPrimary,
                              borderRadius: BorderRadius.circular(4),
                            ),
                          ),
                          const SizedBox(height: 4),
                          Text(
                            entry.key,
                            style: AppTypography.caption(isDark),
                          ),
                        ],
                      );
                    }).toList(),
                  ),
                );
              },
              loading: () => const Center(child: CircularProgressIndicator()),
              error: (error, stack) => Text(
                '차트를 불러올 수 없습니다',
                style: AppTypography.body2(isDark),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildFrequentRestaurants(
    AsyncValue<List<({String restaurantId, int visitCount})>> frequentAsync,
    WidgetRef ref,
    bool isDark,
  ) {
    return 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(
              '자주 방문한 맛집 TOP 3',
              style: AppTypography.heading2(isDark),
            ),
            const SizedBox(height: 16),
            frequentAsync.when(
              data: (frequentList) {
                if (frequentList.isEmpty) {
                  return Center(
                    child: Text(
                      '아직 방문 기록이 없습니다',
                      style: AppTypography.body2(isDark),
                    ),
                  );
                }
                
                return Column(
                  children: frequentList.take(3).map((item) {
                    final restaurantAsync = ref.watch(restaurantProvider(item.restaurantId));
                    
                    return restaurantAsync.when(
                      data: (restaurant) {
                        if (restaurant == null) return const SizedBox.shrink();
                        
                        return Padding(
                          padding: const EdgeInsets.only(bottom: 12),
                          child: Row(
                            children: [
                              Container(
                                width: 32,
                                height: 32,
                                decoration: BoxDecoration(
                                  color: AppColors.lightPrimary.withOpacity(0.1),
                                  shape: BoxShape.circle,
                                ),
                                child: Center(
                                  child: Text(
                                    '${frequentList.indexOf(item) + 1}',
                                    style: AppTypography.body1(isDark).copyWith(
                                      color: AppColors.lightPrimary,
                                      fontWeight: FontWeight.bold,
                                    ),
                                  ),
                                ),
                              ),
                              const SizedBox(width: 12),
                              Expanded(
                                child: Column(
                                  crossAxisAlignment: CrossAxisAlignment.start,
                                  children: [
                                    Text(
                                      restaurant.name,
                                      style: AppTypography.body1(isDark).copyWith(
                                        fontWeight: FontWeight.w500,
                                      ),
                                      maxLines: 1,
                                      overflow: TextOverflow.ellipsis,
                                    ),
                                    Text(
                                      restaurant.category,
                                      style: AppTypography.caption(isDark),
                                    ),
                                  ],
                                ),
                              ),
                              Text(
                                '${item.visitCount}회',
                                style: AppTypography.body2(isDark).copyWith(
                                  color: AppColors.lightPrimary,
                                  fontWeight: FontWeight.bold,
                                ),
                              ),
                            ],
                          ),
                        );
                      },
                      loading: () => const SizedBox(height: 44),
                      error: (error, stack) => const SizedBox.shrink(),
                    );
                  }).toList() as List<Widget>,
                );
              },
              loading: () => const Center(child: CircularProgressIndicator()),
              error: (error, stack) => Text(
                '데이터를 불러올 수 없습니다',
                style: AppTypography.body2(isDark),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildStatItem({
    required IconData icon,
    required String label,
    required String value,
    required Color color,
    required bool isDark,
  }) {
    return Row(
      children: [
        Container(
          width: 40,
          height: 40,
          decoration: BoxDecoration(
            color: color.withOpacity(0.1),
            shape: BoxShape.circle,
          ),
          child: Icon(
            icon,
            color: color,
            size: 20,
          ),
        ),
        const SizedBox(width: 12),
        Expanded(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                label,
                style: AppTypography.caption(isDark),
              ),
              Text(
                value,
                style: AppTypography.body1(isDark).copyWith(
                  fontWeight: FontWeight.bold,
                ),
              ),
            ],
          ),
        ),
      ],
    );
  }
}