import 'package:easy_refresh/easy_refresh.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:tdesign_flutter/tdesign_flutter.dart';
import '../../shared/widgets/empty_state.dart';
import '../shell/nav_bar_config.dart';
import '../../core/i18n/app_localizations.dart';
import '../../shared/widgets/message_item.dart';
import '../../shared/widgets/skeleton_list_card.dart';
import 'message_controller.dart';
import 'message_model.dart';
import '../../core/theme/app_colors.dart';
import '../../core/theme/app_colors_extension.dart';

/// 消息通知聚合页
///
/// 展示 5 种消息类型：
/// - 审批待办（📋）→ 详情页 + 审批操作栏
/// - 审批结果（✅/❌）→ 详情查看结果
/// - 撤回通知（↩）→ 消息列表
/// - 系统公告（📢）→ 公告详情
/// - 过期提醒（⏰）→ 对应详情页
///
/// 左滑操作：标记已读（蓝）+ 删除（红）。已读消息不可左滑。
class MessageListPage extends ConsumerWidget {
  const MessageListPage({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final colors = Theme.of(context).extension<AppColorsExtension>()!;
    final messagesAsync = ref.watch(messageListProvider);
    final unreadCount = ref.watch(unreadCountProvider);
    final location = GoRouterState.of(context).uri.toString();
    final l10n = AppLocalizations.of(context);

    if (location.startsWith('/messages')) {
      ref
          .read(navBarConfigProvider.notifier)
          .update(
            NavBarConfig(
              title: l10n.get('messageNotifications'),
              showBack: true,
              leadingIcon: Icons.close,
              // 仅在有未读时显示"全部已读"按钮
              showRight: unreadCount > 0,
              rightWidget: unreadCount > 0
                  ? GestureDetector(
                      onTap: () {
                        TDMessage.showMessage(
                          context: context,
                          content: l10n.get('markAllRead'),
                          theme: MessageTheme.success,
                          icon: true,
                          duration: 2000,
                        );
                      },
                      child: Padding(
                        padding: const EdgeInsets.symmetric(
                          horizontal: 12,
                          vertical: 8,
                        ),
                        child: Text(
                          l10n.get('markAllRead'),
                          style: TextStyle(
                            fontSize: AppFontSizes.body,
                            color: colors.primary,
                          ),
                        ),
                      ),
                    )
                  : null,
            ),
          );
    }

    // 首次加载：展示骨架屏，不包裹 EasyRefresh
    if (messagesAsync.isLoading && !messagesAsync.hasValue) {
      return SkeletonLoadingList(
        cardBuilder: () => const SkeletonMessageCard(),
      );
    }

    return EasyRefresh(
      header: TDRefreshHeader(),
      onRefresh: () async {
        ref.invalidate(messageListProvider);
        await ref.read(messageListProvider.future);
      },
      child: _buildContent(context, ref, messagesAsync, l10n),
    );
  }

  /// 根据加载状态构建列表内容
  ///
  /// - [AsyncValue.isReloading]：下拉刷新中，展示旧数据 + header loading
  /// - [AsyncValue.hasError]：错误状态
  /// - 空数据：空状态
  /// - 正常数据：消息列表
  Widget _buildContent(
    BuildContext context,
    WidgetRef ref,
    AsyncValue<List<MessageModel>> messagesAsync,
    AppLocalizations l10n,
  ) {
    // 下拉刷新中：保留旧数据 + EasyRefresh header loading
    if (messagesAsync.isReloading) {
      final oldItems = messagesAsync.valueOrNull ?? [];
      if (oldItems.isEmpty) {
        return SingleChildScrollView(
          physics: const AlwaysScrollableScrollPhysics(),
          child: EmptyState(message: l10n.get('noMessages')),
        );
      }
      return ListView.separated(
        padding: const EdgeInsets.fromLTRB(
          AppSpacing.md,
          AppSpacing.md,
          AppSpacing.md,
          AppSpacing.lg,
        ),
        itemCount: oldItems.length,
        separatorBuilder: (_, _) => const SizedBox(height: 12),
        itemBuilder: (_, i) => _buildItem(context, ref, oldItems[i], l10n),
      );
    }

    // 错误
    if (messagesAsync.hasError) {
      return SingleChildScrollView(
        physics: const AlwaysScrollableScrollPhysics(),
        child: EmptyState(message: l10n.get('loadFailed')),
      );
    }

    // 空数据
    final messages = messagesAsync.requireValue;
    if (messages.isEmpty) {
      return SingleChildScrollView(
        physics: const AlwaysScrollableScrollPhysics(),
        child: EmptyState(message: l10n.get('noMessages')),
      );
    }

    // 正常列表
    return ListView.separated(
      padding: const EdgeInsets.fromLTRB(
        AppSpacing.md,
        AppSpacing.md,
        AppSpacing.md,
        AppSpacing.lg,
      ),
      itemCount: messages.length,
      separatorBuilder: (_, _) => const SizedBox(height: 12),
      itemBuilder: (_, i) => _buildItem(context, ref, messages[i], l10n),
    );
  }

  Widget _buildItem(
    BuildContext context,
    WidgetRef ref,
    MessageModel msg,
    AppLocalizations l10n,
  ) {
    final colors = Theme.of(context).extension<AppColorsExtension>()!;
    final (icon, iconColor, iconBg) = _messageIconProps(msg.msgType, colors);

    return MessageItem(
      icon: icon,
      iconColor: iconColor,
      iconBackground: iconBg,
      title: msg.title,
      time: _formatTime(msg.createTime),
      sender: _messageSender(msg.msgType, l10n),
      summary: msg.content,
      unread: !msg.isRead,
      onTap: () => _navigateToBiz(context, msg),
      // 仅未读消息展示左滑操作
      onToggleRead: msg.isRead
          ? null
          : () {
              TDMessage.showMessage(
                context: context,
                content: '${l10n.get("markRead")}：${msg.title}',
                theme: MessageTheme.success,
                icon: true,
                duration: 2000,
              );
            },
      onDelete: () {
        showDialog(
          context: context,
          builder: (ctx) => TDAlertDialog(
            title: l10n.get('confirm'),
            content: l10n.getString(
              'confirmAction',
              args: {'action': l10n.get('delete')},
            ),
            leftBtn: TDDialogButtonOptions(
              title: l10n.get('cancel'),
              action: () => Navigator.of(ctx).pop(),
            ),
            rightBtn: TDDialogButtonOptions(
              title: l10n.get('confirm'),
              action: () {
                Navigator.of(ctx).pop();
                TDMessage.showMessage(
                  context: context,
                  content: '${l10n.get("deletedToast")}${msg.title}',
                  theme: MessageTheme.warning,
                  icon: true,
                  duration: 2000,
                );
              },
            ),
          ),
        );
      },
    );
  }

  /// 按消息类型返回（图标, 图标色, 图标背景色）
  (IconData, Color, Color) _messageIconProps(
    String msgType,
    AppColorsExtension colors,
  ) {
    switch (msgType) {
      case 'announcement':
        return (Icons.campaign_outlined, colors.warning, colors.warningBg);
      case 'approval_result':
        return (Icons.check_circle_outlined, colors.success, colors.successBg);
      case 'withdraw_notice':
        return (Icons.undo_outlined, colors.statusGray, colors.swipeDeleteBg);
      case 'expiry_reminder':
        return (Icons.timer_off_outlined, colors.danger, colors.dangerBg);
      case 'approval_notice':
      default:
        return (Icons.assignment_outlined, colors.primary, colors.primaryLight);
    }
  }

  /// 按消息类型返回发送者标签
  String _messageSender(String msgType, AppLocalizations l10n) {
    switch (msgType) {
      case 'announcement':
        return l10n.get('systemNotice');
      case 'approval_notice':
        return l10n.get('approvalNotice');
      case 'approval_result':
        return l10n.get('systemMessage');
      case 'withdraw_notice':
        return l10n.get('systemMessage');
      case 'expiry_reminder':
        return l10n.get('systemMessage');
      default:
        return l10n.get('systemMessage');
    }
  }

  /// 格式化时间为 MM-DD HH:mm
  String _formatTime(DateTime time) {
    final month = time.month.toString().padLeft(2, '0');
    final day = time.day.toString().padLeft(2, '0');
    final hour = time.hour.toString().padLeft(2, '0');
    final minute = time.minute.toString().padLeft(2, '0');
    return '$month-$day $hour:$minute';
  }

  /// 按 BizType 路由跳转
  void _navigateToBiz(BuildContext context, MessageModel msg) {
    if (msg.bizType == null || msg.bizId == null) return;
    switch (msg.bizType) {
      case 'expense':
        context.push('/expense/detail/${msg.bizId}');
        break;
      case 'overtime':
        context.push('/overtime/detail/${msg.bizId}');
        break;
      case 'vehicle':
        context.push('/vehicle/detail/${msg.bizId}');
        break;
      case 'announcement':
        context.push('/announcement/detail/${msg.bizId}');
        break;
      case 'expense_application':
        context.push('/expense-apply/detail/${msg.bizId}');
        break;
    }
  }
}