class Todo {
  final String id;
  final String title;
  final String? description;
  final bool isCompleted;
  final String priority;
  final DateTime? dueDate;
  final int sortOrder;
  final DateTime? createdAt;
  final DateTime? updatedAt;

  const Todo({
    required this.id,
    required this.title,
    this.description,
    this.isCompleted = false,
    this.priority = 'medium',
    this.dueDate,
    this.sortOrder = 0,
    this.createdAt,
    this.updatedAt,
  });

  Todo copyWith({
    String? id,
    String? title,
    String? description,
    bool? isCompleted,
    String? priority,
    DateTime? dueDate,
    int? sortOrder,
    DateTime? createdAt,
    DateTime? updatedAt,
  }) {
    return Todo(
      id: id ?? this.id,
      title: title ?? this.title,
      description: description ?? this.description,
      isCompleted: isCompleted ?? this.isCompleted,
      priority: priority ?? this.priority,
      dueDate: dueDate ?? this.dueDate,
      sortOrder: sortOrder ?? this.sortOrder,
      createdAt: createdAt ?? this.createdAt,
      updatedAt: updatedAt ?? this.updatedAt,
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'title': title,
      'description': description,
      'isCompleted': isCompleted,
      'priority': priority,
      'dueDate': dueDate?.toIso8601String(),
      'sortOrder': sortOrder,
      'createdAt': createdAt?.toIso8601String(),
      'updatedAt': updatedAt?.toIso8601String(),
    };
  }

  factory Todo.fromJson(Map<String, dynamic> json) {
    return Todo(
      id: json['id'] as String,
      title: json['title'] as String,
      description: json['description'] as String?,
      isCompleted: json['isCompleted'] as bool? ?? false,
      priority: json['priority'] as String? ?? 'medium',
      dueDate: json['dueDate'] != null ? DateTime.parse(json['dueDate'] as String) : null,
      sortOrder: json['sortOrder'] as int? ?? 0,
      createdAt: json['createdAt'] != null ? DateTime.parse(json['createdAt'] as String) : null,
      updatedAt: json['updatedAt'] != null ? DateTime.parse(json['updatedAt'] as String) : null,
    );
  }

  @override
  bool operator ==(Object other) =>
      identical(this, other) ||
      other is Todo && id == other.id;

  @override
  int get hashCode => id.hashCode;

  @override
  String toString() => 'Todo(id: $id, title: $title, isCompleted: $isCompleted)';
}