feat: transfer api for stock module

stock/models.py

@@ -371,3 +371,134 @@ class StockFreeze(ModelBase):
     class Meta:
         verbose_name = '库存冻结'
         verbose_name_plural = '库存冻结'
+
+
+class TransferOrderStatusEnum(models.IntegerChoices):
+    DRAFT = 1, '待完成'
+    COMPLETED = 2, '已完成'
+    CANCELLED = 3, '已取消'
+
+
+class TransferOrder(ModelBase):
+    """跨仓调拨单"""
+
+    id = models.BigAutoField(primary_key=True)
+    merchant = models.ForeignKey(
+        basic_info_models.Merchant,
+        on_delete=models.PROTECT,
+        related_name='transfer_orders',
+        verbose_name='所属商户',
+    )
+    from_warehouse = models.ForeignKey(
+        basic_info_models.WareHouse,
+        on_delete=models.PROTECT,
+        related_name='outgoing_transfer_orders',
+        verbose_name='调出仓',
+    )
+    to_warehouse = models.ForeignKey(
+        basic_info_models.WareHouse,
+        on_delete=models.PROTECT,
+        related_name='incoming_transfer_orders',
+        verbose_name='调入仓',
+    )
+    mode = models.IntegerField(
+        choices=basic_info_models.WareHouseModeEnum.choices,
+        verbose_name='调拨模式',
+    )
+    operator = models.ForeignKey(
+        basic_info_models.Employee,
+        on_delete=models.PROTECT,
+        related_name='transfer_orders',
+        verbose_name='经办人',
+    )
+    created_by = models.ForeignKey(
+        'auth.User',
+        on_delete=models.PROTECT,
+        null=True,
+        blank=True,
+        related_name='created_transfer_orders',
+        verbose_name='创建人',
+    )
+    transfer_date = models.DateField(verbose_name='调拨日期')
+    status = models.IntegerField(
+        choices=TransferOrderStatusEnum.choices,
+        default=TransferOrderStatusEnum.DRAFT,
+        verbose_name='状态',
+    )
+    remarks = models.TextField(blank=True, null=True, verbose_name='备注')
+    request_id = models.CharField(max_length=64, blank=True, null=True, verbose_name='请求ID')
+    outgoing_record = models.ForeignKey(
+        'stock.StockChangeRecord',
+        on_delete=models.PROTECT,
+        related_name='transfer_out_orders',
+        null=True,
+        blank=True,
+        verbose_name='调出出入库记录',
+    )
+    incoming_record = models.ForeignKey(
+        'stock.StockChangeRecord',
+        on_delete=models.PROTECT,
+        related_name='transfer_in_orders',
+        null=True,
+        blank=True,
+        verbose_name='调入出入库记录',
+    )
+
+    class Meta:
+        verbose_name = '调拨单'
+        verbose_name_plural = '调拨单'
+        constraints = [
+            models.UniqueConstraint(
+                fields=['merchant', 'request_id'],
+                condition=models.Q(request_id__isnull=False),
+                name='unique_transfer_request_per_merchant',
+            ),
+            models.CheckConstraint(
+                check=~models.Q(from_warehouse=models.F('to_warehouse')),
+                name='transfer_different_warehouses',
+            ),
+        ]
+
+    def clean(self):
+        super().clean()
+        if self.from_warehouse_id and self.to_warehouse_id:
+            if self.from_warehouse_id == self.to_warehouse_id:
+                raise ValidationError('调拨的出入库仓库不能相同')
+            if self.from_warehouse.merchant_id != self.merchant_id or self.to_warehouse.merchant_id != self.merchant_id:
+                raise ValidationError('调拨仓库必须属于当前商户')
+            if self.from_warehouse.mode != self.to_warehouse.mode:
+                raise ValidationError('调拨要求出入库仓库的模式一致')
+            if self.mode and self.mode != self.from_warehouse.mode:
+                raise ValidationError('调拨模式与仓库模式不一致')
+
+    def __str__(self):
+        return f'调拨单 {self.id} - {self.from_warehouse.name} -> {self.to_warehouse.name}'
+
+
+class TransferOrderItem(ModelBase):
+    id = models.BigAutoField(primary_key=True)
+    transfer_order = models.ForeignKey(
+        TransferOrder,
+        on_delete=models.CASCADE,
+        related_name='items',
+        verbose_name='调拨单',
+    )
+    product = models.ForeignKey(
+        basic_info_models.Product,
+        on_delete=models.PROTECT,
+        related_name='transfer_order_items',
+        verbose_name='产品',
+    )
+    unit = models.IntegerField(
+        choices=basic_info_models.ProductUnitEnum.choices,
+        verbose_name='单位',
+    )
+    total_quantity = models.DecimalField(max_digits=10, decimal_places=2, verbose_name='数量合计')
+    num_of_rolls = models.PositiveIntegerField(default=1, verbose_name='匹数')
+
+    class Meta:
+        verbose_name = '调拨单明细'
+        verbose_name_plural = '调拨单明细'
+
+    def __str__(self):
+        return f'调拨明细 {self.id} - 产品: {self.product.name}'