import 'package:json_annotation/json_annotation.dart';

part 'notification_model.g.dart';

/// 通知模型
@JsonSerializable()
class NotificationModel {
  final int id;
  
  @JsonKey(name: 'user_id')
  final int userId;
  
  final String type;
  final String title;
  final String content;
  final String? link;
  
  @JsonKey(name: 'is_read')
  final bool isRead;
  
  final int priority;
  
  @JsonKey(name: 'created_at')
  final DateTime createdAt;
  
  @JsonKey(name: 'read_at')
  final DateTime? readAt;

  const NotificationModel({
    required this.id,
    required this.userId,
    required this.type,
    required this.title,
    required this.content,
    this.link,
    required this.isRead,
    required this.priority,
    required this.createdAt,
    this.readAt,
  });

  factory NotificationModel.fromJson(Map<String, dynamic> json) =>
      _$NotificationModelFromJson(json);

  Map<String, dynamic> toJson() => _$NotificationModelToJson(this);

  /// 通知类型
  String get typeLabel {
    switch (type) {
      case 'system':
        return '系统通知';
      case 'learning':
        return '学习提醒';
      case 'achievement':
        return '成就通知';
      default:
        return '通知';
    }
  }

  /// 优先级
  String get priorityLabel {
    switch (priority) {
      case 0:
        return '普通';
      case 1:
        return '重要';
      case 2:
        return '紧急';
      default:
        return '普通';
    }
  }

  /// 格式化时间
  String get timeAgo {
    final now = DateTime.now();
    final difference = now.difference(createdAt);

    if (difference.inDays > 0) {
      return '${difference.inDays}天前';
    } else if (difference.inHours > 0) {
      return '${difference.inHours}小时前';
    } else if (difference.inMinutes > 0) {
      return '${difference.inMinutes}分钟前';
    } else {
      return '刚刚';
    }
  }
}