class NumberRule {
  final int id;
  final String type;
  final String prefix;
  final int currentNo;
  final String dateFormat;

  const NumberRule({
    required this.id,
    required this.type,
    required this.prefix,
    required this.currentNo,
    required this.dateFormat,
  });

  String get typeLabel {
    switch (type) {
      case 'stock_in':
        return '入库单';
      case 'stock_out':
        return '出库单';
      case 'inventory_check':
        return '盘点单';
      case 'product':
        return '商品编码';
      default:
        return type;
    }
  }

  String get exampleNo {
    final now = DateTime.now();
    final date = '${now.year}${now.month.toString().padLeft(2, '0')}${now.day.toString().padLeft(2, '0')}';
    return '$prefix$date${(currentNo + 1).toString().padLeft(3, '0')}';
  }

  factory NumberRule.fromJson(Map<String, dynamic> json) => NumberRule(
        id: (json['id'] as num).toInt(),
        type: json['type'] as String,
        prefix: json['prefix'] as String? ?? '',
        currentNo: (json['current_no'] as num).toInt(),
        dateFormat: json['date_format'] as String? ?? 'YYYYMMDD',
      );
}