class Inventory {
  final int warehouseId;
  final String? warehouseName;
  final int productId;
  final String? productName;
  final String? productCode;
  final String? productSpec;
  final String? productUnit;
  final String? productBrand;
  final int? minStock;
  final double quantity;

  const Inventory({
    required this.warehouseId,
    this.warehouseName,
    required this.productId,
    this.productName,
    this.productCode,
    this.productSpec,
    this.productUnit,
    this.productBrand,
    this.minStock,
    required this.quantity,
  });

  factory Inventory.fromJson(Map<String, dynamic> json) {
    final warehouse = json['warehouse'] as Map<String, dynamic>?;
    final product = json['product'] as Map<String, dynamic>?;
    return Inventory(
      warehouseId: (json['warehouse_id'] as num).toInt(),
      warehouseName: warehouse?['name'] as String?,
      productId: (json['product_id'] as num).toInt(),
      productName: product?['name'] as String?,
      productCode: product?['code'] as String?,
      productSpec: product?['spec'] as String?,
      productUnit: product?['unit'] as String?,
      productBrand: product?['brand'] as String?,
      minStock: product?['min_stock'] != null
          ? (product!['min_stock'] as num).toInt()
          : null,
      quantity: (json['quantity'] as num).toDouble(),
    );
  }
}

// 商品追踪：已审核入库单的明细行，含库存状态和买家信息
class ProductTrackingRecord {
  final int id;
  final int productId;
  final String? productName;
  final String? productCode;
  final String? productSpec;
  final String? productUnit;
  final String? batchNo;
  final double quantity;
  final double unitPrice;
  final String? orderNo;
  final String? orderDate;
  final String? warehouseName;
  final String? supplierName;
  // 库存状态
  final double currentQty;
  final String status; // in_stock | sold_out
  final String? buyerName;
  final String? soldAt;

  const ProductTrackingRecord({
    required this.id,
    required this.productId,
    this.productName,
    this.productCode,
    this.productSpec,
    this.productUnit,
    this.batchNo,
    required this.quantity,
    required this.unitPrice,
    this.orderNo,
    this.orderDate,
    this.warehouseName,
    this.supplierName,
    required this.currentQty,
    required this.status,
    this.buyerName,
    this.soldAt,
  });

  bool get isSoldOut => status == 'sold_out';

  factory ProductTrackingRecord.fromJson(Map<String, dynamic> json) {
    final product = json['product'] as Map<String, dynamic>?;
    final order = json['order'] as Map<String, dynamic>?;
    final warehouse = order?['warehouse'] as Map<String, dynamic>?;
    final partner = order?['partner'] as Map<String, dynamic>?;
    return ProductTrackingRecord(
      id: (json['id'] as num).toInt(),
      productId: (json['product_id'] as num).toInt(),
      productName: product?['name'] as String?,
      productCode: product?['code'] as String?,
      productSpec: product?['spec'] as String?,
      productUnit: product?['unit'] as String?,
      batchNo: json['batch_no'] as String?,
      quantity: (json['quantity'] as num).toDouble(),
      unitPrice: (json['unit_price'] as num).toDouble(),
      orderNo: order?['order_no'] as String?,
      orderDate: order?['order_date'] as String?,
      warehouseName: warehouse?['name'] as String?,
      supplierName: partner?['name'] as String?,
      currentQty: json['current_qty'] != null
          ? (json['current_qty'] as num).toDouble()
          : 0,
      status: json['status'] as String? ?? 'in_stock',
      buyerName: json['buyer_name'] as String?,
      soldAt: json['sold_at'] as String?,
    );
  }
}

class InventoryLog {
  final int warehouseId;
  final String? warehouseName;
  final int productId;
  final String? productName;
  final String direction; // in | out
  final double quantity;
  final double? qtyBefore;
  final double? qtyAfter;
  final String? refType;
  final int? refId;
  final String? createdAt;

  const InventoryLog({
    required this.warehouseId,
    this.warehouseName,
    required this.productId,
    this.productName,
    required this.direction,
    required this.quantity,
    this.qtyBefore,
    this.qtyAfter,
    this.refType,
    this.refId,
    this.createdAt,
  });

  factory InventoryLog.fromJson(Map<String, dynamic> json) => InventoryLog(
        warehouseId: (json['warehouse_id'] as num).toInt(),
        warehouseName: (json['warehouse'] as Map<String, dynamic>?)?['name'] as String?,
        productId: (json['product_id'] as num).toInt(),
        productName: (json['product'] as Map<String, dynamic>?)?['name'] as String?,
        direction: json['direction'] as String,
        quantity: (json['quantity'] as num).toDouble(),
        qtyBefore: json['qty_before'] != null
            ? (json['qty_before'] as num).toDouble()
            : null,
        qtyAfter: json['qty_after'] != null
            ? (json['qty_after'] as num).toDouble()
            : null,
        refType: json['ref_type'] as String?,
        refId: json['ref_id'] != null
            ? (json['ref_id'] as num).toInt()
            : null,
        createdAt: json['created_at'] as String?,
      );
}