feat: allocation record for pre sales order

business/allocation_services.py

@@ -0,0 +1,140 @@
+from __future__ import annotations
+
+from decimal import Decimal
+from typing import Iterable, List
+
+from django.db import transaction
+
+from stock import models as stock_models
+from . import models
+
+
+def _normalize_stock_ids(stock_ids: Iterable[int | str]) -> List[int]:
+    if not stock_ids:
+        raise ValueError('stock_ids 不能为空')
+    normalized: List[int] = []
+    for raw in stock_ids:
+        try:
+            value = int(raw)
+        except (TypeError, ValueError) as exc:
+            raise ValueError('stock_ids 必须为整数数组') from exc
+        if value <= 0:
+            raise ValueError('stock_ids 必须为正整数数组')
+        normalized.append(value)
+    return normalized
+
+
+def _serialize_stock_ids(stock_ids: Iterable[int]) -> str:
+    return ','.join(str(value) for value in stock_ids)
+
+
+def validate_stock_details(*, merchant, stock_ids: Iterable[int | str]) -> List[stock_models.StockChangeDetail]:
+    normalized_ids = _normalize_stock_ids(stock_ids)
+
+    details_by_id = stock_models.StockChangeDetail.objects.filter(
+        id__in=normalized_ids,
+        merchant=merchant,
+    ).in_bulk(field_name='id')
+
+    missing_ids = [value for value in normalized_ids if value not in details_by_id]
+    if missing_ids:
+        raise ValueError(f'库存明细不存在: {missing_ids}')
+
+    consumed_ids = [
+        detail.id
+        for detail in details_by_id.values()
+        if getattr(detail, 'is_consumed', False)
+    ]
+    if consumed_ids:
+        raise ValueError(f'库存明细已被消费: {consumed_ids}')
+
+    frozen_ids = list(
+        stock_models.StockFreeze.objects.filter(
+            stock_detail_id__in=normalized_ids,
+            status=stock_models.StockFreezeStatusEnum.FROZEN,
+        ).values_list('stock_detail_id', flat=True)
+    )
+    if frozen_ids:
+        raise ValueError(f'库存明细已被冻结: {list(frozen_ids)}')
+
+    return [details_by_id[value] for value in normalized_ids]
+
+
+def create_allocation_record(
+    *,
+    item: models.PreSalesOrderItem,
+    stock_ids: Iterable[int | str],
+    quantity: Decimal | int | str,
+    unit: str | None,
+    scanned_by,
+    remarks: str | None = None,
+) -> models.AllocationRecord:
+    if quantity is None or str(quantity) == '':
+        raise ValueError('quantity 不能为空')
+    try:
+        quantity_decimal = Decimal(str(quantity))
+    except Exception as exc:
+        raise ValueError('quantity 格式不正确') from exc
+    if quantity_decimal <= 0:
+        raise ValueError('quantity 必须大于 0')
+
+    if not unit:
+        unit = getattr(item, 'unit', None)
+    unit = (unit or '').strip()
+    if not unit:
+        raise ValueError('unit 不能为空')
+
+    order = getattr(item, 'pre_sales_order', None)
+    if order is None:
+        raise ValueError('明细缺少所属预销售单')
+
+    normalized_ids = _normalize_stock_ids(stock_ids)
+    details = validate_stock_details(merchant=order.merchant, stock_ids=normalized_ids)
+
+    item_product_id = getattr(item, 'product_id', None)
+    if item_product_id:
+        mismatch_ids = list(
+            stock_models.StockChangeDetail.objects.filter(
+                id__in=normalized_ids,
+            ).exclude(product_id=item_product_id).values_list('id', flat=True)
+        )
+        if mismatch_ids:
+            raise ValueError(f'库存明细产品不匹配: {mismatch_ids}')
+
+    with transaction.atomic():
+        record = models.AllocationRecord.objects.create(
+            pre_sales_order_item=item,
+            stock_ids=_serialize_stock_ids(normalized_ids),
+            quantity=quantity_decimal,
+            unit=unit,
+            status=models.AllocationRecordStatusEnum.ACTIVE,
+            scanned_by=scanned_by,
+            remarks=remarks,
+        )
+
+        stock_models.StockFreeze.objects.bulk_create(
+            [
+                stock_models.StockFreeze(
+                    merchant=order.merchant,
+                    product=detail.product,
+                    warehouse=order.warehouse,
+                    stock_detail=detail,
+                    quantity=detail.quantity,
+                    unit=detail.unit,
+                    status=stock_models.StockFreezeStatusEnum.FROZEN,
+                    frozen_by=getattr(scanned_by, 'sys_user', None),
+                    frozen_with=record.id,
+                )
+                for detail in details
+            ]
+        )
+
+    return record
+
+
+def cancel_allocation_record(*, record: models.AllocationRecord) -> models.AllocationRecord:
+    if record.status == models.AllocationRecordStatusEnum.CANCELLED:
+        return record
+    record.status = models.AllocationRecordStatusEnum.CANCELLED
+    record.save(update_fields=['status', 'updated_at'])
+    return record