最低价格约束

web/services/product_sku.go

@@ -32,7 +32,7 @@ func (s *productSkuService) Page(req *core.PageReq, productId *int32) (result []
 	return q.ProductSku.
 		Joins(q.ProductSku.Discount).
 		Where(do...).
-		Order(q.ProductSku.CreatedAt.Desc()).
+		Order(q.ProductSku.ID).
 		FindByPage(req.GetOffset(), req.GetLimit())
 }
 
@@ -42,12 +42,18 @@ func (s *productSkuService) Create(create CreateProductSkuData) (err error) {
 		return core.NewBizErr("产品价格的格式不正确", err)
 	}
 
+	priceMin, err := decimal.NewFromString(create.PriceMin)
+	if err != nil {
+		return core.NewBizErr("产品最低价格的格式不正确", err)
+	}
+
 	return q.ProductSku.Create(&m.ProductSku{
 		ProductID:  create.ProductID,
 		DiscountId: create.DiscountID,
 		Code:       create.Code,
 		Name:       create.Name,
 		Price:      price,
+		PriceMin:   priceMin,
 	})
 }
 
@@ -57,6 +63,7 @@ type CreateProductSkuData struct {
 	Code       string `json:"code"`
 	Name       string `json:"name"`
 	Price      string `json:"price"`
+	PriceMin   string `json:"price_min"`
 }
 
 func (s *productSkuService) Update(update UpdateProductSkuData) (err error) {
@@ -69,6 +76,13 @@ func (s *productSkuService) Update(update UpdateProductSkuData) (err error) {
 		}
 		do = append(do, q.ProductSku.Price.Value(price))
 	}
+	if update.PriceMin != "" {
+		priceMin, err := decimal.NewFromString(update.PriceMin)
+		if err != nil {
+			return core.NewBizErr("产品最低价格的格式不正确", err)
+		}
+		do = append(do, q.ProductSku.PriceMin.Value(priceMin))
+	}
 	if update.DiscountID != nil {
 		do = append(do, q.ProductSku.DiscountId.Value(*update.DiscountID))
 	}
@@ -92,6 +106,7 @@ type UpdateProductSkuData struct {
 	Code       *string `json:"code"`
 	Name       *string `json:"name"`
 	Price      *string `json:"price"`
+	PriceMin   string  `json:"price_min"`
 	Status     *int32  `json:"status"`
 }
 

web/services/resource.go

@@ -196,6 +196,14 @@ func (s *resourceService) CalcPrice(skuCode string, count int32, user *m.User, c
 		couponApplied = discounted.Sub(coupon.Amount)
 	}
 
+	// 约束到最低价格
+	if discounted.Cmp(sku.PriceMin) < 0 {
+		discounted = sku.PriceMin.Copy()
+	}
+	if couponApplied.Cmp(sku.PriceMin) < 0 {
+		couponApplied = sku.PriceMin.Copy()
+	}
+
 	return sku, discount, coupon, discounted, couponApplied, nil
 }