feat: transfer api for stock module

stock/services.py

@@ -678,6 +678,123 @@ class StockFlowService:
         return payload
 
 
+def _aggregate_transfer_details(details: List[models.StockChangeDetail]) -> Dict[int, Dict[str, Any]]:
+    aggregated: Dict[int, Dict[str, Any]] = {}
+    for detail in details:
+        product_id = detail.product_id
+        if product_id not in aggregated:
+            aggregated[product_id] = {
+                'product': detail.product,
+                'unit': detail.unit,
+                'total': Decimal('0'),
+                'num_of_rolls': 0,
+            }
+        aggregated[product_id]['total'] += Decimal(detail.quantity)
+        aggregated[product_id]['num_of_rolls'] += 1
+    return aggregated
+
+
+def create_transfer_order(
+    *,
+    merchant: basic_models.Merchant,
+    created_by,
+    operator: basic_models.Employee,
+    from_warehouse_id: int,
+    to_warehouse_id: int,
+    items: List[Dict[str, Any]],
+    transfer_date=None,
+    remarks: str | None = '',
+    request_id: str | None = None,
+) -> models.TransferOrder:
+    if not merchant:
+        raise ValueError('必须提供商户信息')
+    if operator is None:
+        raise ValueError('必须提供调拨经办人')
+    if operator.merchant_id != merchant.id:
+        raise ValueError('经办人不属于当前商户')
+    if not items:
+        raise ValueError('调拨产品明细不能为空')
+    if not from_warehouse_id or not to_warehouse_id:
+        raise ValueError('必须提供调出仓和调入仓')
+    if from_warehouse_id == to_warehouse_id:
+        raise ValueError('调入仓与调出仓不能相同')
+
+    transfer_date = transfer_date or timezone.now().date()
+
+    if request_id:
+        existing = models.TransferOrder.objects.filter(merchant=merchant, request_id=request_id).first()
+        if existing:
+            return existing
+
+    try:
+        from_warehouse = basic_models.WareHouse.objects.get(id=from_warehouse_id, merchant=merchant)
+    except basic_models.WareHouse.DoesNotExist:
+        raise ValueError('调出仓不存在或不属于当前商户')
+
+    try:
+        to_warehouse = basic_models.WareHouse.objects.get(id=to_warehouse_id, merchant=merchant)
+    except basic_models.WareHouse.DoesNotExist:
+        raise ValueError('调入仓不存在或不属于当前商户')
+
+    if from_warehouse.mode != to_warehouse.mode:
+        raise ValueError('调拨要求调出仓与调入仓的出入库模式一致')
+    if from_warehouse.mode == basic_models.WareHouseModeEnum.RESTRICT_IN_OUT:
+        raise ValueError('调拨暂不支持严进严出模式，请先转为其他模式')
+
+    flow_service = StockFlowService(merchant=merchant, created_by=created_by)
+
+    with transaction.atomic():
+        transfer_order = models.TransferOrder.objects.create(
+            merchant=merchant,
+            from_warehouse=from_warehouse,
+            to_warehouse=to_warehouse,
+            operator=operator,
+            created_by=created_by,
+            transfer_date=transfer_date,
+            status=models.TransferOrderStatusEnum.DRAFT,
+            remarks=remarks or '',
+            mode=from_warehouse.mode,
+            request_id=request_id,
+        )
+
+        out_record, out_details, _ = flow_service.stock_out(
+            warehouse_id=from_warehouse.id,
+            source_type=models.StockChangeSourceEnum.TRANSPORT_OUT,
+            source_id=transfer_order.id,
+            items=items,
+        )
+        in_record, _, _ = flow_service.stock_in(
+            warehouse_id=to_warehouse.id,
+            source_type=models.StockChangeSourceEnum.TRANSPORT_IN,
+            source_id=transfer_order.id,
+            items=items,
+        )
+
+        make_stock_change_completed(out_record)
+        make_stock_change_completed(in_record)
+
+        aggregated = _aggregate_transfer_details(out_details)
+        transfer_items = [
+            models.TransferOrderItem(
+                transfer_order=transfer_order,
+                product=data['product'],
+                unit=data['unit'],
+                total_quantity=data['total'],
+                num_of_rolls=data['num_of_rolls'],
+            )
+            for data in aggregated.values()
+        ]
+        if transfer_items:
+            models.TransferOrderItem.objects.bulk_create(transfer_items)
+
+        transfer_order.outgoing_record = out_record
+        transfer_order.incoming_record = in_record
+        transfer_order.status = models.TransferOrderStatusEnum.COMPLETED
+        transfer_order.save(update_fields=['outgoing_record', 'incoming_record', 'status'])
+
+    return transfer_order
+
+
 def find_inventory(product_id: int, warehouse_id: int) -> models.Inventory | None:
     """根据产品ID和仓库ID查找库存记录"""