// 首页·日记流 — 严格对齐 spec §3.4 home-daily.html
//
// 视觉层级（从上到下）：
// 1. 问候语 + 日期（右上角搜索按钮）
// 2. 连续记录徽章 streak-badge (pill)
// 3. 心情选择器（5 选 1，bg=#FFFFFF surface 卡片）
// 4. "今天的日记" 渐变卡片 + 浮动写按钮
// 5. 三栏统计（本月日记/连续天数/总日记数）
// 6. 最近记录标题 + 查看全部
// 7. 日记卡片列表
//
// 颜色规范（spec §7.1）：
// - 页面背景用 var(--bg) #FFF8F0（不是纯白）
// - Card 用 var(--surface) #FFFFFF（与页面背景形成层次）

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:go_router/go_router.dart';

import '../../../core/constants/design_tokens.dart';
import '../../../core/theme/app_colors.dart';
import '../../../core/theme/app_radius.dart';
import '../../../core/theme/app_shadows.dart';
import '../../../core/theme/app_typography.dart';
import '../../../data/models/journal_entry.dart';
import '../../../data/repositories/journal_repository.dart';
import '../bloc/home_bloc.dart';

class HomePage extends StatelessWidget {
  const HomePage({super.key});

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) => HomeBloc(
        journalRepository: context.read<JournalRepository>(),
      )..add(const HomeLoadData()),
      child: const _HomeView(),
    );
  }
}

class _HomeView extends StatelessWidget {
  const _HomeView();

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final isDark = theme.brightness == Brightness.dark;
    final bg = isDark ? AppColors.bgDark : AppColors.bgLight;

    return BlocBuilder<HomeBloc, HomeState>(
      builder: (context, state) {
        final loaded = state is HomeLoaded ? state : const HomeLoaded();
        final isLoading = state is HomeLoading;

        return Scaffold(
          backgroundColor: bg,
          body: isLoading
              ? const Center(child: CircularProgressIndicator())
              : RefreshIndicator(
                  onRefresh: () async {
                    context.read<HomeBloc>().add(const HomeRefresh());
                  },
                  child: _buildContent(context, loaded),
                ),
        );
      },
    );
  }

  Widget _buildContent(BuildContext context, HomeLoaded state) {
    final now = DateTime.now();
    final greeting = _greeting(now.hour);
    final dateText = _formatDate(now);

    return SingleChildScrollView(
      physics: const AlwaysScrollableScrollPhysics(),
      padding: EdgeInsets.fromLTRB(
        DesignTokens.spacing20,
        MediaQuery.of(context).padding.top + DesignTokens.spacing8,
        DesignTokens.spacing20,
        DesignTokens.spacing24,
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          _GreetingHeader(
            greeting: greeting,
            username: '小暖',
            dateText: dateText,
            onSearchTap: () => context.push('/search'),
          ),
          const SizedBox(height: DesignTokens.spacing16),

          if (state.streakDays > 0) ...[
            _StreakBadge(days: state.streakDays),
            const SizedBox(height: DesignTokens.spacing16),
          ],

          _MoodSelectorCard(
            topMood: state.topMood,
            todayWeather: state.todayWeather,
            onMoodTap: (_) => context.push('/editor'),
          ),
          const SizedBox(height: DesignTokens.spacing20),

          _TodayCard(
            hasTodayEntry: state.hasTodayEntry,
            onTap: () => context.push('/editor'),
          ),
          const SizedBox(height: DesignTokens.spacing20),

          _QuickStats(
            monthCount: state.monthCount,
            streakDays: state.streakDays,
            totalCount: state.totalCount,
          ),
          const SizedBox(height: DesignTokens.spacing24),

          _SectionHeader(
            title: '最近记录',
            onSeeAll: () => context.go('/calendar'),
          ),
          const SizedBox(height: DesignTokens.spacing12),

          state.recentJournals.isEmpty
              ? const _EmptyJournalState()
              : _JournalList(journals: state.recentJournals),
        ],
      ),
    );
  }

  String _greeting(int hour) {
    if (hour < 6) return '夜深了';
    if (hour < 11) return '早上好';
    if (hour < 14) return '中午好';
    if (hour < 18) return '下午好';
    if (hour < 22) return '晚上好';
    return '夜深了';
  }

  String _formatDate(DateTime now) {
    const weekdays = ['周一', '周二', '周三', '周四', '周五', '周六', '周日'];
    final w = weekdays[now.weekday - 1];
    return '${now.year}年${now.month}月${now.day}日 · $w';
  }
}

/// 1. 顶部问候 + 日期 + 搜索按钮
class _GreetingHeader extends StatelessWidget {
  const _GreetingHeader({
    required this.greeting,
    required this.username,
    required this.dateText,
    required this.onSearchTap,
  });

  final String greeting;
  final String username;
  final String dateText;
  final VoidCallback onSearchTap;

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

    return Row(
      crossAxisAlignment: CrossAxisAlignment.center,
      children: [
        Expanded(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                dateText,
                style: TextStyle(fontSize: 13, color: muted, fontWeight: FontWeight.w500),
              ),
              const SizedBox(height: 4),
              Text.rich(
                TextSpan(
                  style: TextStyle(
                    fontFamily: AppTypography.displayFont,
                    fontSize: 30,
                    fontWeight: FontWeight.w700,
                    color: fg,
                    height: 1.2,
                  ),
                  children: [
                    TextSpan(text: '$greeting，'),
                    TextSpan(
                      text: username,
                      style: TextStyle(color: colorScheme.primary),
                    ),
                  ],
                ),
              ),
            ],
          ),
        ),
        InkWell(
          onTap: onSearchTap,
          customBorder: const CircleBorder(),
          child: Container(
            width: DesignTokens.touchMin,
            height: DesignTokens.touchMin,
            decoration: BoxDecoration(
              color: colorScheme.surface,
              shape: BoxShape.circle,
              boxShadow: AppShadows.soft(context),
            ),
            child: Icon(Icons.search_rounded, size: 20, color: fg),
          ),
        ),
      ],
    );
  }
}

/// 2. 连续记录徽章 (pill, tertiary-soft 背景)
class _StreakBadge extends StatelessWidget {
  const _StreakBadge({required this.days});
  final int days;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 6),
      decoration: BoxDecoration(
        color: AppColors.tertiarySoftLight,
        borderRadius: AppRadius.pillBorder,
      ),
      child: Row(
        mainAxisSize: MainAxisSize.min,
        children: [
          const Icon(
            Icons.local_fire_department_rounded,
            size: 14,
            color: Color(0xFFB8860B),
          ),
          const SizedBox(width: 4),
          Text(
            '连续记录 $days 天',
            style: const TextStyle(
              fontSize: 13,
              fontWeight: FontWeight.w600,
              color: Color(0xFFB8860B),
            ),
          ),
        ],
      ),
    );
  }
}

/// 3. 心情选择器卡片 — bg=#FFFFFF, radius=16
class _MoodSelectorCard extends StatelessWidget {
  const _MoodSelectorCard({
    required this.topMood,
    required this.todayWeather,
    required this.onMoodTap,
  });

  final Mood? topMood;
  final Weather? todayWeather;
  final ValueChanged<Mood> onMoodTap;

  static const _moods = [
    ('😊', '开心', Mood.happy),
    ('😐', '平静', Mood.calm),
    ('😢', '难过', Mood.sad),
    ('😡', '生气', Mood.angry),
    ('🤔', '思考', Mood.thinking),
  ];

  static const _weatherMap = {
    Weather.sunny: ('☀', '晴'),
    Weather.cloudy: ('☁', '多云'),
    Weather.rainy: ('🌧', '雨'),
    Weather.snowy: ('❄', '雪'),
    Weather.windy: ('💨', '风'),
  };

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

    return Container(
      width: double.infinity,
      padding: const EdgeInsets.symmetric(
        horizontal: DesignTokens.spacing20,
        vertical: DesignTokens.spacing16,
      ),
      decoration: BoxDecoration(
        color: theme.colorScheme.surface,
        borderRadius: AppRadius.mdBorder,
        boxShadow: AppShadows.soft(context),
      ),
      child: Column(
        children: [
          Row(
            children: [
              Text(
                '今天心情如何？',
                style: TextStyle(
                  fontFamily: AppTypography.handwrittenFont,
                  fontSize: 17,
                  fontWeight: FontWeight.w600,
                  color: theme.colorScheme.onSurface,
                ),
              ),
              const Spacer(),
              Builder(builder: (context) {
                final w = _weatherMap[todayWeather] ?? _weatherMap[Weather.sunny]!;
                return Text(
                  '${w.$1} ${w.$2}',
                  style: TextStyle(fontSize: 13, color: theme.colorScheme.onSurfaceVariant),
                );
              }),
            ],
          ),
          const SizedBox(height: DesignTokens.spacing12),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: _moods.map((m) {
              final isTop = topMood == m.$3;
              return InkWell(
                onTap: () => onMoodTap(m.$3),
                customBorder: const CircleBorder(),
                child: _MoodOption(
                  emoji: m.$1,
                  label: m.$2,
                  selected: isTop,
                ),
              );
            }).toList(),
          ),
        ],
      ),
    );
  }
}

class _MoodOption extends StatelessWidget {
  const _MoodOption({
    required this.emoji,
    required this.label,
    required this.selected,
  });

  final String emoji;
  final String label;
  final bool selected;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        AnimatedContainer(
          duration: DesignTokens.animFast,
          width: DesignTokens.touchMin,
          height: DesignTokens.touchMin,
          alignment: Alignment.center,
          decoration: BoxDecoration(
            color: selected ? AppColors.surfaceWarmLight : Colors.transparent,
            borderRadius: AppRadius.mdBorder,
          ),
          child: Text(emoji, style: const TextStyle(fontSize: 28)),
        ),
        const SizedBox(height: 4),
        Text(
          label,
          style: TextStyle(
            fontSize: 11,
            fontWeight: selected ? FontWeight.w600 : FontWeight.w500,
            color: selected ? theme.colorScheme.primary : theme.colorScheme.onSurfaceVariant,
          ),
        ),
      ],
    );
  }
}

/// 4. "今天的日记" 渐变卡片 + 浮动写按钮
class _TodayCard extends StatelessWidget {
  const _TodayCard({required this.hasTodayEntry, required this.onTap});
  final bool hasTodayEntry;
  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    return Material(
      color: Colors.transparent,
      child: InkWell(
        onTap: onTap,
        borderRadius: AppRadius.lgBorder,
        child: Container(
          width: double.infinity,
          padding: const EdgeInsets.all(DesignTokens.spacing24),
          decoration: BoxDecoration(
            gradient: const LinearGradient(
              begin: Alignment.topLeft,
              end: Alignment.bottomRight,
              colors: [AppColors.accent, AppColors.tertiary],
            ),
            borderRadius: AppRadius.lgBorder,
            boxShadow: [
              BoxShadow(
                color: AppColors.accent.withValues(alpha: 0.25),
                offset: const Offset(0, 4),
                blurRadius: 14,
              ),
            ],
          ),
          child: Stack(
            children: [
              Positioned(
                right: -30,
                top: -30,
                child: Container(
                  width: 120,
                  height: 120,
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: Colors.white.withValues(alpha: 0.12),
                  ),
                ),
              ),
              Positioned(
                left: -20,
                bottom: -20,
                child: Container(
                  width: 80,
                  height: 80,
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: Colors.white.withValues(alpha: 0.08),
                  ),
                ),
              ),
              Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text(
                    '今天的日记',
                    style: TextStyle(
                      fontFamily: AppTypography.handwrittenFont,
                      fontSize: 13,
                      color: Colors.white.withValues(alpha: 0.85),
                    ),
                  ),
                  const SizedBox(height: 8),
                  Text(
                    hasTodayEntry ? '继续今天的记录' : '写点什么吧...',
                    style: const TextStyle(
                      fontSize: 24,
                      fontWeight: FontWeight.w700,
                      color: AppColors.bgLight,
                    ),
                  ),
                  const SizedBox(height: 6),
                  Text(
                    '记录一个温暖的瞬间...',
                    style: TextStyle(
                      fontSize: 13,
                      color: Colors.white.withValues(alpha: 0.75),
                    ),
                  ),
                ],
              ),
              Positioned(
                right: DesignTokens.spacing20,
                bottom: DesignTokens.spacing20,
                child: Material(
                  color: Colors.white,
                  shape: const CircleBorder(),
                  elevation: 4,
                  child: InkWell(
                    onTap: onTap,
                    customBorder: const CircleBorder(),
                    child: SizedBox(
                      width: 48,
                      height: 48,
                      child: Icon(Icons.add_rounded, size: 22, color: AppColors.accent),
                    ),
                  ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

/// 5. 三栏统计
class _QuickStats extends StatelessWidget {
  const _QuickStats({
    required this.monthCount,
    required this.streakDays,
    required this.totalCount,
  });

  final int monthCount;
  final int streakDays;
  final int totalCount;

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Expanded(child: _stat(context, '$monthCount', '本月日记', AppColors.accent)),
        const SizedBox(width: DesignTokens.spacing12),
        Expanded(child: _stat(context, '$streakDays', '连续天数', AppColors.secondary)),
        const SizedBox(width: DesignTokens.spacing12),
        Expanded(child: _stat(context, '$totalCount', '总日记数', AppColors.fgLight)),
      ],
    );
  }

  Widget _stat(BuildContext context, String num, String label, Color color) {
    final theme = Theme.of(context);
    return Container(
      padding: const EdgeInsets.all(DesignTokens.spacing16),
      decoration: BoxDecoration(
        color: theme.colorScheme.surface,
        borderRadius: AppRadius.mdBorder,
        boxShadow: AppShadows.soft(context),
      ),
      child: Column(
        children: [
          Text(
            num,
            style: TextStyle(
              fontFamily: AppTypography.displayFont,
              fontSize: 30,
              fontWeight: FontWeight.w700,
              color: color,
            ),
          ),
          const SizedBox(height: 2),
          Text(
            label,
            style: TextStyle(fontSize: 11, color: theme.colorScheme.onSurfaceVariant),
          ),
        ],
      ),
    );
  }
}

/// 6. 区块标题
class _SectionHeader extends StatelessWidget {
  const _SectionHeader({required this.title, required this.onSeeAll});

  final String title;
  final VoidCallback onSeeAll;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        Text(
          title,
          style: TextStyle(
            fontFamily: AppTypography.displayFont,
            fontSize: 20,
            fontWeight: FontWeight.w700,
            color: theme.colorScheme.onSurface,
          ),
        ),
        TextButton(
          onPressed: onSeeAll,
          style: TextButton.styleFrom(
            foregroundColor: theme.colorScheme.primary,
            minimumSize: const Size(44, 32),
            padding: const EdgeInsets.symmetric(horizontal: 8),
          ),
          child: const Text('查看全部', style: TextStyle(fontSize: 13, fontWeight: FontWeight.w500)),
        ),
      ],
    );
  }
}

/// 7. 日记列表
class _JournalList extends StatelessWidget {
  const _JournalList({required this.journals});
  final List<JournalEntry> journals;

  @override
  Widget build(BuildContext context) {
    return Column(
      children: journals
          .map((j) => Padding(
                padding: const EdgeInsets.only(bottom: DesignTokens.spacing12),
                child: _JournalCard(journal: j),
              ))
          .toList(),
    );
  }
}

class _JournalCard extends StatelessWidget {
  const _JournalCard({required this.journal});
  final JournalEntry journal;

  String _moodEmoji(Mood m) => switch (m) {
        Mood.happy => '😊',
        Mood.calm => '😐',
        Mood.sad => '😢',
        Mood.angry => '😡',
        Mood.thinking => '🤔',
      };

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final moodColor = AppColors.moodColors[journal.mood.value] ?? AppColors.accent;
    final excerpt = journal.contentExcerpt?.isNotEmpty == true
        ? journal.contentExcerpt!
        : (journal.tags.isEmpty ? '点击查看详情' : journal.tags.take(3).map((t) => '#$t').join(' '));

    return Material(
      color: theme.colorScheme.surface,
      borderRadius: AppRadius.mdBorder,
      child: InkWell(
        onTap: () => context.push('/editor?id=${journal.id}'),
        borderRadius: AppRadius.mdBorder,
        child: Container(
          padding: const EdgeInsets.all(DesignTokens.spacing16),
          decoration: BoxDecoration(
            borderRadius: AppRadius.mdBorder,
            border: Border.all(color: theme.colorScheme.outlineVariant),
          ),
          child: Row(
            children: [
              Container(
                width: 72,
                height: 72,
                decoration: BoxDecoration(
                  color: AppColors.surfaceWarmLight,
                  borderRadius: AppRadius.smBorder,
                ),
                alignment: Alignment.center,
                child: Text(_moodEmoji(journal.mood), style: const TextStyle(fontSize: 32)),
              ),
              const SizedBox(width: DesignTokens.spacing16),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '${journal.date.month}月${journal.date.day}日',
                      style: TextStyle(fontSize: 11, color: theme.colorScheme.onSurfaceVariant),
                    ),
                    const SizedBox(height: 2),
                    Text(
                      journal.title,
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                      style: TextStyle(
                        fontFamily: AppTypography.displayFont,
                        fontSize: 15,
                        fontWeight: FontWeight.w600,
                        color: theme.colorScheme.onSurface,
                      ),
                    ),
                    const SizedBox(height: 4),
                    Text(
                      excerpt,
                      maxLines: 2,
                      overflow: TextOverflow.ellipsis,
                      style: TextStyle(fontSize: 13, color: theme.colorScheme.onSurfaceVariant, height: 1.5),
                    ),
                  ],
                ),
              ),
              const SizedBox(width: 8),
              Container(
                width: 28,
                height: 28,
                decoration: BoxDecoration(
                  color: moodColor.withValues(alpha: 0.15),
                  shape: BoxShape.circle,
                ),
                alignment: Alignment.center,
                child: Text(_moodEmoji(journal.mood), style: const TextStyle(fontSize: 14)),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class _EmptyJournalState extends StatelessWidget {
  const _EmptyJournalState();

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Center(
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: DesignTokens.spacing40),
        child: Column(
          children: [
            Icon(
              Icons.auto_stories_rounded,
              size: 64,
              color: theme.colorScheme.onSurface.withValues(alpha: 0.2),
            ),
            const SizedBox(height: DesignTokens.spacing16),
            Text(
              '开始你的第一篇手账日记吧！',
              style: theme.textTheme.bodyLarge?.copyWith(
                color: theme.colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: DesignTokens.spacing24),
            FilledButton.icon(
              onPressed: () => context.push('/editor'),
              icon: const Icon(Icons.add_rounded),
              label: const Text('写日记'),
              style: FilledButton.styleFrom(
                backgroundColor: AppColors.accent,
                foregroundColor: AppColors.bgLight,
                shape: RoundedRectangleBorder(borderRadius: AppRadius.pillBorder),
                padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
              ),
            ),
          ],
        ),
      ),
    );
  }
}