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

import '../../core/theme/app_theme.dart';
import '../../providers/auth_provider.dart';
import '../../providers/notification_provider.dart';
import '../../services/notification_service.dart';
import '../feed/widgets/feed_overlays.dart';

/// 消息通知页（《03-接口文档》10.2~10.4）：
/// 类型筛选 + 触底分页 + 单条/全部已读；审核结果跳我的作品，提现进度跳资产页
class NotificationsScreen extends ConsumerStatefulWidget {
  const NotificationsScreen({super.key});

  @override
  ConsumerState<NotificationsScreen> createState() =>
      _NotificationsScreenState();
}

class _NotificationsScreenState extends ConsumerState<NotificationsScreen> {
  final _scroll = ScrollController();

  static const List<Map<String, dynamic>> _filters = [
    {'label': '全部', 'value': null},
    {'label': '审核', 'value': 1},
    {'label': '提现', 'value': 2},
    {'label': '公告', 'value': 3},
    {'label': '回复', 'value': 4},
  ];

  @override
  void initState() {
    super.initState();
    _scroll.addListener(_onScroll);
  }

  @override
  void dispose() {
    _scroll.dispose();
    super.dispose();
  }

  void _onScroll() {
    if (_scroll.position.pixels >= _scroll.position.maxScrollExtent - 200) {
      ref.read(notificationsProvider.notifier).loadMore();
    }
  }

  @override
  Widget build(BuildContext context) {
    final isLoggedIn = ref.watch(authProvider).isLoggedIn;
    if (!isLoggedIn) {
      return Scaffold(
        appBar: AppBar(title: const Text('消息通知')),
        body: _GuestGuide(onLogin: () => context.push('/login')),
      );
    }

    final state = ref.watch(notificationsProvider);
    return Scaffold(
      appBar: AppBar(
        title: const Text('消息通知'),
        actions: [
          TextButton(
            onPressed: state.markingAll || state.items.isEmpty
                ? null
                : () => _markAll(context),
            child: const Text('全部已读'),
          ),
        ],
      ),
      body: Column(
        children: [
          // 类型筛选
          SizedBox(
            height: 52,
            child: ListView(
              scrollDirection: Axis.horizontal,
              padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
              children: _filters.map((f) {
                final active = state.type == f['value'];
                return Padding(
                  padding: const EdgeInsets.only(right: 8),
                  child: ChoiceChip(
                    label: Text(f['label'] as String),
                    selected: active,
                    onSelected: (_) => ref
                        .read(notificationsProvider.notifier)
                        .setType(f['value'] as int?),
                    selectedColor: AppColors.primary,
                    backgroundColor: AppColors.surface,
                    labelStyle: TextStyle(
                      color: active ? Colors.white : AppColors.textSecondary,
                    ),
                  ),
                );
              }).toList(),
            ),
          ),
          Expanded(child: _buildBody(state)),
        ],
      ),
    );
  }

  Widget _buildBody(NotificationsState state) {
    if (state.isLoading && state.items.isEmpty) {
      return const Center(child: CircularProgressIndicator());
    }
    if (state.loadFailed && state.items.isEmpty) {
      return _LoadFailed(
        onRetry: () => ref.read(notificationsProvider.notifier).load(),
      );
    }
    if (state.items.isEmpty) {
      return const Center(
        child: Text('暂无消息', style: TextStyle(color: AppColors.textWeak)),
      );
    }
    return RefreshIndicator(
      onRefresh: () => ref.read(notificationsProvider.notifier).load(),
      child: ListView.separated(
        controller: _scroll,
        padding: const EdgeInsets.symmetric(vertical: 8),
        itemCount: state.items.length + (state.hasMore ? 1 : 0),
        separatorBuilder: (_, __) => const Divider(height: 1, indent: 16),
        itemBuilder: (context, index) {
          if (index >= state.items.length) {
            return const Padding(
              padding: EdgeInsets.all(16),
              child: Center(
                child: SizedBox(
                  width: 20,
                  height: 20,
                  child: CircularProgressIndicator(strokeWidth: 2),
                ),
              ),
            );
          }
          final item = state.items[index];
          return _NotificationTile(
            item: item,
            onTap: () => _onTapItem(item),
          );
        },
      ),
    );
  }

  Future<void> _onTapItem(NotificationItem item) async {
    await ref.read(notificationsProvider.notifier).markOneRead(item);
    if (!mounted) return;
    // 按类型跳关联页面
    switch (item.type) {
      case 1: // 审核结果 → 我的作品
        context.push('/mine/works');
        break;
      case 2: // 提现进度 → 资产页
        context.push('/assets');
        break;
      default:
        break;
    }
  }

  Future<void> _markAll(BuildContext context) async {
    try {
      await ref.read(notificationsProvider.notifier).markAllRead();
    } catch (_) {
      if (context.mounted) showTopToast(context, '操作失败，请稍后重试');
    }
  }
}

class _NotificationTile extends StatelessWidget {
  const _NotificationTile({required this.item, required this.onTap});

  final NotificationItem item;
  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: onTap,
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            // 未读红点
            Padding(
              padding: const EdgeInsets.only(top: 6),
              child: Icon(
                Icons.circle,
                size: 8,
                color: item.isRead ? Colors.transparent : AppColors.primary,
              ),
            ),
            const SizedBox(width: 8),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Row(
                    children: [
                      // 类型标签
                      Container(
                        padding: const EdgeInsets.symmetric(
                          horizontal: 5,
                          vertical: 1,
                        ),
                        decoration: BoxDecoration(
                          color: AppColors.surface,
                          borderRadius: BorderRadius.circular(3),
                        ),
                        child: Text(
                          item.typeLabel,
                          style: const TextStyle(
                            color: AppColors.textSecondary,
                            fontSize: 10,
                          ),
                        ),
                      ),
                      const SizedBox(width: 6),
                      Expanded(
                        child: Text(
                          item.title,
                          overflow: TextOverflow.ellipsis,
                          style: TextStyle(
                            fontSize: 15,
                            fontWeight: item.isRead
                                ? FontWeight.w400
                                : FontWeight.w600,
                            color: item.isRead
                                ? AppColors.textSecondary
                                : Colors.white,
                          ),
                        ),
                      ),
                    ],
                  ),
                  if (item.content.isNotEmpty) ...[
                    const SizedBox(height: 4),
                    Text(
                      item.content,
                      maxLines: 2,
                      overflow: TextOverflow.ellipsis,
                      style: const TextStyle(
                        color: AppColors.textSecondary,
                        fontSize: 13,
                      ),
                    ),
                  ],
                  const SizedBox(height: 4),
                  Text(
                    item.createdAt,
                    style: const TextStyle(
                      color: AppColors.textWeak,
                      fontSize: 11,
                    ),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _GuestGuide extends StatelessWidget {
  const _GuestGuide({required this.onLogin});

  final VoidCallback onLogin;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          const Icon(Icons.notifications_none,
              size: 64, color: AppColors.textWeak),
          const SizedBox(height: 12),
          const Text('登录后查看消息通知',
              style: TextStyle(color: AppColors.textSecondary)),
          const SizedBox(height: 16),
          ElevatedButton(
            onPressed: onLogin,
            style: ElevatedButton.styleFrom(
              minimumSize: const Size(160, 44),
            ),
            child: const Text('去登录'),
          ),
        ],
      ),
    );
  }
}

class _LoadFailed extends StatelessWidget {
  const _LoadFailed({required this.onRetry});

  final VoidCallback onRetry;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          const Text('加载失败', style: TextStyle(color: AppColors.textSecondary)),
          const SizedBox(height: 12),
          TextButton(onPressed: onRetry, child: const Text('点击重试')),
        ],
      ),
    );
  }
}