class UserInfo { final int id; final String? name; final String? username; UserInfo({ required this.id, this.name, this.username, }); factory UserInfo.fromJson(Map json) { return UserInfo( id: json['id'] as int, name: json['name'] as String?, username: json['username'] as String?, ); } Map toJson() { return { 'id': id, 'name': name, 'username': username, }; } String get displayName { if (username != null && username!.isNotEmpty) { if (name != null && name!.isNotEmpty) { return '$username ($name)'; } return username!; } return name ?? 'User $id'; } }