feat: added pre sales order in business module, and explode tests of business module

business/models.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 from decimal import Decimal
 from typing import List
 from django.db import models
+from django.core.exceptions import ValidationError
 from flower.common import ModelBase
 from basic_info import models as basic_info_models
 
@@ -360,6 +361,146 @@ class SalesOrderItem(ModelBase):
         return round(self.price * self.real_quantity(), 2)
 
 
+class PreSalesOrder(ModelBase):
+    """预销售单
+
+    预销售单用于在客户下达采购/要货指令时，提前通知仓库进行库存核对与调货。
+
+    目前阶段：仅定义 PreSalesOrder 与 PreSalesOrderItem 的一对多关系，
+    并关联 customer 与 created_by；其他业务对象（如 Warehouse / StockChangeRecord / StockFreeze 等）
+    暂不在此模型中建立关联。
+    """
+
+    id = models.BigAutoField(primary_key=True)
+
+    merchant = models.ForeignKey(
+        basic_info_models.Merchant,
+        on_delete=models.PROTECT,
+        related_name='pre_sales_orders',
+        verbose_name='所属商户',
+    )
+    customer = models.ForeignKey(
+        basic_info_models.Customer,
+        on_delete=models.PROTECT,
+        related_name='pre_sales_orders',
+        verbose_name='客户',
+    )
+    created_by = models.ForeignKey(
+        basic_info_models.Employee,
+        on_delete=models.PROTECT,
+        related_name='created_pre_sales_orders',
+        null=True,
+        blank=True,
+        verbose_name='创建者',
+    )
+    warehouse = models.ForeignKey(
+        basic_info_models.WareHouse,
+        on_delete=models.PROTECT,
+        related_name='pre_sales_orders',
+        verbose_name='仓库',
+    )
+    kind = models.IntegerField(
+        choices=SalesOrderKindEnum.choices,
+        default=SalesOrderKindEnum.WHOLESALE,
+        verbose_name='预销售单类型',
+    )
+    remarks = models.TextField(blank=True, null=True, verbose_name='备注')
+
+    def __str__(self):
+        return f'预销售单 {self.human_id or self.id}'
+
+    def clean(self):
+        super().clean()
+
+        errors = {}
+
+        if getattr(self, 'merchant_id', None) and getattr(self, 'customer_id', None):
+            if self.customer.merchant_id != self.merchant_id:
+                errors['customer'] = '客户所属商户与预销售单所属商户不一致'
+
+        if getattr(self, 'merchant_id', None) and getattr(self, 'warehouse_id', None):
+            if self.warehouse.merchant_id != self.merchant_id:
+                errors['warehouse'] = '仓库所属商户与预销售单所属商户不一致'
+
+        if getattr(self, 'created_by_id', None) and getattr(self, 'merchant_id', None):
+            if self.created_by.merchant_id != self.merchant_id:
+                errors['created_by'] = '创建者所属商户与预销售单所属商户不一致'
+
+        if errors:
+            raise ValidationError(errors)
+
+    @property
+    def customer_name(self) -> str:
+        if getattr(self, 'customer_id', None):
+            return self.customer.name
+        return ''
+
+    @property
+    def merchant_name(self) -> str:
+        if getattr(self, 'merchant_id', None):
+            return self.merchant.name
+        return ''
+
+    @property
+    def created_by_name(self) -> str:
+        if getattr(self, 'created_by_id', None):
+            return self.created_by.name
+        return ''
+
+    @property
+    def warehouse_name(self) -> str:
+        if getattr(self, 'warehouse_id', None):
+            return self.warehouse.name
+        return ''
+
+    @property
+    def human_id(self) -> str:
+        """人类可读编号（虚拟编号，不落库）。
+
+        规则：YS + YYYYMMDD{6位id}
+        """
+        if self.id is None or self.created_at is None:
+            return ""
+        return f"YS{self.created_at.year}{self.created_at.month:02d}{self.created_at.day:02d}{self.id:06d}"
+
+    class Meta:
+        verbose_name = '预销售单'
+        verbose_name_plural = '预销售单'
+
+
+class PreSalesOrderItem(ModelBase):
+    """预销售单明细"""
+
+    id = models.BigAutoField(primary_key=True)
+    pre_sales_order = models.ForeignKey(
+        PreSalesOrder,
+        on_delete=models.CASCADE,
+        related_name='items',
+        verbose_name='预销售单',
+    )
+
+    # 暂不与 Product 建立外键，先用弱关联字段承载。
+    product_id = models.BigIntegerField(null=True, blank=True, verbose_name='产品ID')
+    product_name = models.CharField(max_length=100, blank=True, default='', verbose_name='产品名称')
+
+    color = models.CharField(max_length=50, null=True, blank=True, verbose_name='颜色')
+    quantity = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True, verbose_name='数量')
+    unit = models.CharField(max_length=50, blank=True, default='', verbose_name='单位')
+    spec = models.CharField(max_length=100, null=True, blank=True, verbose_name='规格')
+    quantity_of_rolls = models.TextField(
+        null=True,
+        blank=True,
+        verbose_name='各条数数量',
+    )
+    num_of_rolls = models.PositiveIntegerField(default=1, verbose_name='条数')
+    order_quantity = models.IntegerField(null=True, blank=True, verbose_name='下单数量')
+    remarks = models.TextField(blank=True, null=True, verbose_name='备注')
+
+    class Meta:
+        verbose_name = '预销售单明细'
+        verbose_name_plural = '预销售单明细'
+
+
 class PurchaseReturnStatusEnum(models.IntegerChoices):
     PENDING = 1, '审批中'
     APPROVED = 2, '审批通过'