// 周概览页面 — 7天条目 + 统计卡片 + 每日日记卡片
// 对齐 Open Design 原型稿 screens/weekly.html
// 接入 JournalRepository 加载真实数据

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:nuanji_app/core/theme/app_colors.dart';
import 'package:nuanji_app/core/theme/app_radius.dart';
import 'package:nuanji_app/core/theme/app_shadows.dart';
import 'package:nuanji_app/core/theme/app_typography.dart';
import 'package:nuanji_app/core/utils/mood_utils.dart';
import 'package:nuanji_app/data/models/journal_entry.dart';
import 'package:nuanji_app/data/repositories/journal_repository.dart';

/// 周概览页面
class WeeklyPage extends StatefulWidget {
  const WeeklyPage({super.key});

  @override
  State<WeeklyPage> createState() => _WeeklyPageState();
}

class _WeeklyPageState extends State<WeeklyPage> {
  late DateTime _focusedWeekStart;
  List<JournalEntry> _journals = [];
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    final now = DateTime.now();
    _focusedWeekStart = _startOfWeek(now);
    _loadWeekData();
  }

  JournalRepository get _repo => context.read<JournalRepository>();

  /// 获取某天的周一日期
  DateTime _startOfWeek(DateTime date) {
    return date.subtract(Duration(days: date.weekday - 1));
  }

  Future<void> _loadWeekData() async {
    if (!mounted) return;
    setState(() => _isLoading = true);

    try {
      final weekEnd = _focusedWeekStart.add(const Duration(days: 7));
      final journals = await _repo.getJournals(
        dateFrom: _focusedWeekStart,
        dateTo: weekEnd,
      );
      if (mounted) {
        setState(() {
          _journals = journals;
          _isLoading = false;
        });
      }
    } catch (e) {
      debugPrint('WeeklyPage._loadWeekData 失败: $e');
      if (mounted) setState(() => _isLoading = false);
    }
  }

  void _goToPreviousWeek() {
    setState(() {
      _focusedWeekStart = _focusedWeekStart.subtract(const Duration(days: 7));
    });
    _loadWeekData();
  }

  void _goToNextWeek() {
    setState(() {
      _focusedWeekStart = _focusedWeekStart.add(const Duration(days: 7));
    });
    _loadWeekData();
  }

  /// 按日期索引日记: day-of-week (1=周一..7=周日) → JournalEntry 列表
  Map<int, List<JournalEntry>> get _journalsByWeekday {
    final map = <int, List<JournalEntry>>{};
    for (final j in _journals) {
      // 判断日记日期是否在本周范围内
      final dayKey = j.date.difference(_focusedWeekStart).inDays;
      if (dayKey >= 0 && dayKey < 7) {
        final weekday = dayKey + 1; // 1=周一, 7=周日
        (map[weekday] ??= []).add(j);
      }
    }
    return map;
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;

    return Scaffold(
      body: SafeArea(
        child: Column(
          children: [
            // 周头部导航
            _WeekHeader(
              weekStart: _focusedWeekStart,
              onPrevious: _goToPreviousWeek,
              onNext: _goToNextWeek,
            ),
            // 可滚动内容区
            Expanded(
              child: _isLoading
                  ? const Center(child: CircularProgressIndicator())
                  : ListView(
                      padding: const EdgeInsets.symmetric(horizontal: 20),
                      children: [
                        const SizedBox(height: 16),
                        // 7天条目（真实数据）
                        _WeekStrip(
                          weekStart: _focusedWeekStart,
                          journalsByWeekday: _journalsByWeekday,
                        ),
                        const SizedBox(height: 20),
                        // 本周总结（真实数据）
                        _WeekSummary(journals: _journals),
                        const SizedBox(height: 20),
                        // 每日日记卡片（真实数据）
                        ..._buildDayCards(theme, colorScheme),
                        const SizedBox(height: 32),
                      ],
                    ),
            ),
          ],
        ),
      ),
    );
  }

  List<Widget> _buildDayCards(ThemeData theme, ColorScheme colorScheme) {
    final byWeekday = _journalsByWeekday;
    final cards = <Widget>[];
    final weekNames = ['周一', '周二', '周三', '周四', '周五', '周六', '周日'];

    // 按日期倒序生成卡片（最新的在上面）
    for (var i = 6; i >= 0; i--) {
      final weekday = i + 1;
      final dayJournals = byWeekday[weekday];
      if (dayJournals == null || dayJournals.isEmpty) continue;

      final day = _focusedWeekStart.add(Duration(days: i));
      final first = dayJournals.first;

      cards.add(_DayCard(
        weekday: weekNames[i],
        date: '${day.month}月${day.day}日',
        moodEmoji: moodToEmoji(first.mood),
        weatherEmoji: _weatherEmoji(first.weather),
        body: first.contentExcerpt ?? first.title,
        tags: first.tags.take(2).map((tag) {
          // 根据标签内容选择颜色
          return (tag, AppColors.secondarySoftLight, const Color(0xFF2D7D46));
        }).toList(),
        photoEmoji: dayJournals.any((j) => j.contentExcerpt != null && j.contentExcerpt!.contains('📷'))
            ? '📷'
            : null,
      ));
    }

    // 无日记时显示空状态
    if (cards.isEmpty) {
      return [
        SizedBox(
          height: 200,
          child: Center(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                Icon(Icons.edit_note_rounded, size: 48,
                    color: colorScheme.onSurface.withValues(alpha: 0.2)),
                const SizedBox(height: 12),
                Text('这周还没有日记', style: theme.textTheme.bodyLarge?.copyWith(
                  color: colorScheme.onSurface.withValues(alpha: 0.4),
                )),
              ],
            ),
          ),
        ),
      ];
    }

    return cards;
  }

  String _weatherEmoji(Weather weather) => switch (weather) {
        Weather.sunny => '☀️',
        Weather.cloudy => '⛅',
        Weather.rainy => '🌧️',
        Weather.snowy => '❄️',
        Weather.windy => '💨',
      };
}

// ===== 周头部导航 =====

class _WeekHeader extends StatelessWidget {
  const _WeekHeader({
    required this.weekStart,
    required this.onPrevious,
    required this.onNext,
  });

  final DateTime weekStart;
  final VoidCallback onPrevious;
  final VoidCallback onNext;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;

    // 格式化: "2026年6月 第1周"
    final monthNames = [
      '', '1月', '2月', '3月', '4月', '5月', '6月',
      '7月', '8月', '9月', '10月', '11月', '12月',
    ];
    final title =
        '${weekStart.year}年${monthNames[weekStart.month]} 第${_weekOfMonth(weekStart)}周';

    return Padding(
      padding: const EdgeInsets.fromLTRB(20, 8, 12, 0),
      child: Row(
        children: [
          Expanded(
            child: Text(
              title,
              style: theme.textTheme.headlineSmall?.copyWith(
                fontFamily: AppTypography.displayFont,
                fontWeight: FontWeight.w700,
              ),
            ),
          ),
          // 左右箭头导航按钮
          _NavButton(
            icon: Icons.chevron_left_rounded,
            onTap: onPrevious,
            borderColor: colorScheme.outline,
            foregroundColor: colorScheme.onSurface,
          ),
          const SizedBox(width: 8),
          _NavButton(
            icon: Icons.chevron_right_rounded,
            onTap: onNext,
            borderColor: colorScheme.outline,
            foregroundColor: colorScheme.onSurface,
          ),
        ],
      ),
    );
  }

  /// 计算是当月第几周
  int _weekOfMonth(DateTime date) {
    final firstDay = DateTime(date.year, date.month, 1);
    final offset = firstDay.weekday - 1;
    return ((date.day + offset) / 7).ceil();
  }
}

/// 圆形导航按钮 (44px 触摸目标)
class _NavButton extends StatelessWidget {
  const _NavButton({
    required this.icon,
    required this.onTap,
    required this.borderColor,
    required this.foregroundColor,
  });

  final IconData icon;
  final VoidCallback onTap;
  final Color borderColor;
  final Color foregroundColor;

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      width: 44,
      height: 44,
      child: OutlinedButton(
        onPressed: onTap,
        style: OutlinedButton.styleFrom(
          padding: EdgeInsets.zero,
          shape: const CircleBorder(),
          side: BorderSide(color: borderColor, width: 1.5),
          foregroundColor: foregroundColor,
          backgroundColor: Theme.of(context).colorScheme.surface,
        ),
        child: Icon(icon, size: 18),
      ),
    );
  }
}

// ===== 7天条目（真实数据）=====

class _WeekStrip extends StatelessWidget {
  const _WeekStrip({
    required this.weekStart,
    required this.journalsByWeekday,
  });

  final DateTime weekStart;
  final Map<int, List<JournalEntry>> journalsByWeekday;

  static const _weekNames = ['一', '二', '三', '四', '五', '六', '日'];

  @override
  Widget build(BuildContext context) {
    final colorScheme = Theme.of(context).colorScheme;
    final now = DateTime.now();

    return Row(
      children: List.generate(7, (i) {
        final day = weekStart.add(Duration(days: i));
        final weekday = i + 1;
        final isToday = day.year == now.year &&
            day.month == now.month &&
            day.day == now.day;
        final dayJournals = journalsByWeekday[weekday] ?? [];
        final hasEntry = dayJournals.isNotEmpty;
        final moodEmoji = hasEntry ? moodToEmoji(dayJournals.first.mood) : '·';

        return Expanded(
          child: GestureDetector(
            onTap: () {
              // TODO: 选择某天后刷新下方日记卡片
            },
            child: Container(
              padding: const EdgeInsets.symmetric(vertical: 12),
              decoration: BoxDecoration(
                color: isToday ? AppColors.accent : null,
                borderRadius: AppRadius.mdBorder,
              ),
              child: Column(
                children: [
                  // 周名
                  Text(
                    _weekNames[i],
                    style: TextStyle(
                      fontSize: 11,
                      color: isToday
                          ? const Color(0xFFFFF8F0).withValues(alpha: 0.85)
                          : colorScheme.onSurfaceVariant,
                    ),
                  ),
                  const SizedBox(height: 4),
                  // 日期数字
                  Text(
                    '${day.day}',
                    style: TextStyle(
                      fontFamily: AppTypography.displayFont,
                      fontSize: 20,
                      fontWeight: FontWeight.w700,
                      color: isToday
                          ? const Color(0xFFFFF8F0) // accent-on
                          : colorScheme.onSurface.withValues(alpha: 0.7),
                    ),
                  ),
                  const SizedBox(height: 4),
                  // 心情 emoji
                  Text(moodEmoji, style: TextStyle(
                    fontSize: hasEntry ? 16 : 14,
                    color: hasEntry ? null : colorScheme.onSurface.withValues(alpha: 0.2),
                  )),
                  // 有日记: 日期下方4px小圆点
                  if (hasEntry && !isToday)
                    Container(
                      width: 4,
                      height: 4,
                      margin: const EdgeInsets.only(top: 4),
                      decoration: BoxDecoration(
                        shape: BoxShape.circle,
                        color: AppColors.accent,
                      ),
                    ),
                  if (hasEntry && isToday)
                    Container(
                      width: 4,
                      height: 4,
                      margin: const EdgeInsets.only(top: 4),
                      decoration: const BoxDecoration(
                        shape: BoxShape.circle,
                        color: Color(0xFFFFF8F0),
                      ),
                    ),
                ],
              ),
            ),
          ),
        );
      }),
    );
  }
}

// ===== 本周总结卡片（真实数据）=====

class _WeekSummary extends StatelessWidget {
  const _WeekSummary({required this.journals});

  final List<JournalEntry> journals;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;

    // 统计真实数据
    final recordDays = journals.map((j) => j.date.day).toSet().length;
    final journalCount = journals.length;
    // 统计贴纸元素 — 从日记标签中估算（Phase 1 简化）
    final stickerCount = journals.fold<int>(
      0, (sum, j) => sum + j.tags.length,
    );

    return Container(
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: colorScheme.surface,
        borderRadius: AppRadius.mdBorder,
        boxShadow: AppShadows.soft(context),
        border: Border.all(color: colorScheme.outlineVariant),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            '本周总结',
            style: theme.textTheme.titleMedium?.copyWith(
              fontFamily: AppTypography.displayFont,
              fontWeight: FontWeight.w600,
            ),
          ),
          const SizedBox(height: 16),
          // 3个统计数字
          Row(
            children: [
              _SummaryItem(
                value: '$recordDays',
                label: '记录天数',
                valueColor: AppColors.accent,
              ),
              _SummaryItem(
                value: '$journalCount',
                label: '日记篇数',
                valueColor: AppColors.secondary,
              ),
              _SummaryItem(
                value: '$stickerCount',
                label: '使用标签',
                valueColor: AppColors.tertiary,
              ),
            ],
          ),
          const SizedBox(height: 16),
          // 心情分布条
          _MoodDistributionBar(journals: journals),
        ],
      ),
    );
  }
}

/// 心情分布条 — 从日记数据计算各心情占比
class _MoodDistributionBar extends StatelessWidget {
  const _MoodDistributionBar({required this.journals});
  final List<JournalEntry> journals;

  static const _moodConfig = [
    (Mood.happy, AppColors.secondary),
    (Mood.calm, AppColors.tertiary),
    (Mood.sad, Color(0xFF5B7DB1)),
    (Mood.angry, AppColors.accent),
    (Mood.thinking, Color(0xFF8B7E74)),
  ];

  @override
  Widget build(BuildContext context) {
    if (journals.isEmpty) {
      return Container(
        height: 8,
        decoration: BoxDecoration(
          color: Theme.of(context).colorScheme.outlineVariant.withValues(alpha: 0.3),
          borderRadius: BorderRadius.circular(4),
        ),
      );
    }

    // 统计各心情数量
    final counts = <Mood, int>{};
    for (final j in journals) {
      counts[j.mood] = (counts[j.mood] ?? 0) + 1;
    }

    return Row(
      children: _moodConfig.where((c) => counts[c.$1] != null).map((config) {
        final count = counts[config.$1]!;
        return Expanded(
          flex: count,
          child: Container(
            height: 8,
            margin: const EdgeInsets.only(right: 2),
            decoration: BoxDecoration(
              color: config.$2,
              borderRadius: BorderRadius.circular(4),
            ),
          ),
        );
      }).toList(),
    );
  }
}

/// 单个统计项
class _SummaryItem extends StatelessWidget {
  const _SummaryItem({
    required this.value,
    required this.label,
    required this.valueColor,
  });

  final String value;
  final String label;
  final Color valueColor;

  @override
  Widget build(BuildContext context) {
    return Expanded(
      child: Column(
        children: [
          Text(
            value,
            style: TextStyle(
              fontFamily: AppTypography.displayFont,
              fontSize: 24,
              fontWeight: FontWeight.w700,
              color: valueColor,
            ),
          ),
          const SizedBox(height: 2),
          Text(
            label,
            style: Theme.of(context).textTheme.labelSmall?.copyWith(
                  color: Theme.of(context).colorScheme.onSurfaceVariant,
                ),
          ),
        ],
      ),
    );
  }
}

// ===== 每日日记卡片 =====

class _DayCard extends StatelessWidget {
  const _DayCard({
    required this.weekday,
    required this.date,
    required this.moodEmoji,
    required this.weatherEmoji,
    required this.body,
    required this.tags,
    this.photoEmoji,
  });

  final String weekday;
  final String date;
  final String moodEmoji;
  final String weatherEmoji;
  final String body;
  final List<(String, Color, Color)> tags; // (label, bg, fg)
  final String? photoEmoji;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorScheme = theme.colorScheme;

    return Container(
      margin: const EdgeInsets.only(bottom: 12),
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: colorScheme.surface,
        borderRadius: AppRadius.mdBorder,
        boxShadow: AppShadows.soft(context),
        border: Border.all(color: colorScheme.outlineVariant),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // 头部: 日期 + 心情/weather emoji
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                '$weekday · $date',
                style: theme.textTheme.titleSmall?.copyWith(
                  fontWeight: FontWeight.w600,
                  color: colorScheme.onSurface.withValues(alpha: 0.7),
                ),
              ),
              Text(
                '$moodEmoji $weatherEmoji',
                style: const TextStyle(fontSize: 13),
              ),
            ],
          ),
          const SizedBox(height: 12),
          // 正文预览 (3行截断)
          Text(
            body,
            style: theme.textTheme.bodySmall?.copyWith(
              color: colorScheme.onSurfaceVariant,
              height: 1.6,
            ),
            maxLines: 3,
            overflow: TextOverflow.ellipsis,
          ),
          // 标签 pills
          if (tags.isNotEmpty) ...[
            const SizedBox(height: 12),
            Wrap(
              spacing: 8,
              runSpacing: 4,
              children: tags.map((tag) {
                return Container(
                  padding: const EdgeInsets.symmetric(
                    horizontal: 10,
                    vertical: 3,
                  ),
                  decoration: BoxDecoration(
                    color: tag.$2,
                    borderRadius: AppRadius.pillBorder,
                  ),
                  child: Text(
                    tag.$1,
                    style: TextStyle(
                      fontSize: 11,
                      fontWeight: FontWeight.w500,
                      color: tag.$3,
                    ),
                  ),
                );
              }).toList(),
            ),
          ],
          // 照片占位
          if (photoEmoji != null) ...[
            const SizedBox(height: 12),
            Container(
              width: double.infinity,
              height: 80,
              decoration: BoxDecoration(
                borderRadius: AppRadius.smBorder,
                gradient: LinearGradient(
                  begin: Alignment.topLeft,
                  end: Alignment.bottomRight,
                  colors: [
                    colorScheme.surfaceContainerHighest
                        .withValues(alpha: 0.6),
                    colorScheme.outlineVariant.withValues(alpha: 0.3),
                  ],
                ),
              ),
              alignment: Alignment.center,
              child: Text(photoEmoji!, style: const TextStyle(fontSize: 24)),
            ),
          ],
        ],
      ),
    );
  }
}