feat: add shipping template management and update favicon

backend/internal/api/handlers/order.go

@@ -300,14 +300,80 @@ func (h *OrderHandler) Create(c *gin.Context) {
 		break
 	}
 
-	var shippingFeeFirstWeight, shippingFeePerGram, serviceFeeRate, taxRate, channelFeeRate float64
+	// 获取收货地址省份
+	var shippingAddress models.Address
+	var province string
+	if err := utils.DB.First(&shippingAddress, req.ShippingAddressID).Error; err == nil {
+		province = shippingAddress.Province
+	}
+
+	// 使用运费模板计算运费
+	shippingFee := 0.0
+
+	// 按运费模板分组计算
+	type TemplateGroup struct {
+		TemplateID *uint
+		Weight     float64
+		Quantity   int
+		Subtotal   float64
+	}
+	templateGroups := make(map[uint]*TemplateGroup)
+	noTemplateGroup := &TemplateGroup{Subtotal: 0, Weight: 0, Quantity: 0}
+
+	for _, cart := range carts {
+		var templateID uint
+		if cart.Product.ShippingTemplateID != nil {
+			templateID = *cart.Product.ShippingTemplateID
+		}
+
+		if templateID == 0 {
+			// 没有运费模板，累加到无模板组
+			noTemplateGroup.Weight += cart.Product.Weight * float64(cart.Quantity)
+			noTemplateGroup.Quantity += cart.Quantity
+			noTemplateGroup.Subtotal += cart.Product.Price * float64(cart.Quantity)
+		} else {
+			if _, ok := templateGroups[templateID]; !ok {
+				templateGroups[templateID] = &TemplateGroup{
+					TemplateID: &templateID,
+					Weight:     0,
+					Quantity:   0,
+					Subtotal:   0,
+				}
+			}
+			templateGroups[templateID].Weight += cart.Product.Weight * float64(cart.Quantity)
+			templateGroups[templateID].Quantity += cart.Quantity
+			templateGroups[templateID].Subtotal += cart.Product.Price * float64(cart.Quantity)
+		}
+	}
+
+	// 计算有模板的运费
+	for _, group := range templateGroups {
+		fee, _ := CalculateShippingFee(group.TemplateID, group.Weight, group.Quantity, group.Subtotal, province)
+		shippingFee += fee
+	}
+
+	// 计算无模板的运费（使用旧的系统设置）
+	if noTemplateGroup.Subtotal > 0 {
+		var shippingFeeFirstWeight, shippingFeePerGram float64
+		var setting models.SystemSetting
+		if err := utils.DB.Where("`key` = ?", "shipping_fee_first_weight").First(&setting).Error; err == nil {
+			shippingFeeFirstWeight, _ = strconv.ParseFloat(setting.Value, 64)
+		}
+		if err := utils.DB.Where("`key` = ?", "shipping_fee_per_gram").First(&setting).Error; err == nil {
+			shippingFeePerGram, _ = strconv.ParseFloat(setting.Value, 64)
+		}
+		if noTemplateGroup.Subtotal < 99 && shippingFeeFirstWeight > 0 {
+			fee := shippingFeeFirstWeight
+			if noTemplateGroup.Weight > 500 {
+				fee += shippingFeePerGram * (noTemplateGroup.Weight - 500)
+			}
+			shippingFee += fee
+		}
+	}
+
+	// 获取其他费率
+	var serviceFeeRate, taxRate, channelFeeRate float64
 	var setting models.SystemSetting
-	if err := utils.DB.Where("`key` = ?", "shipping_fee_first_weight").First(&setting).Error; err == nil {
-		shippingFeeFirstWeight, _ = strconv.ParseFloat(setting.Value, 64)
-	}
-	if err := utils.DB.Where("`key` = ?", "shipping_fee_per_gram").First(&setting).Error; err == nil {
-		shippingFeePerGram, _ = strconv.ParseFloat(setting.Value, 64)
-	}
 	if err := utils.DB.Where("`key` = ?", "service_fee_rate").First(&setting).Error; err == nil {
 		serviceFeeRate, _ = strconv.ParseFloat(setting.Value, 64)
 	}
@@ -318,15 +384,6 @@ func (h *OrderHandler) Create(c *gin.Context) {
 		channelFeeRate, _ = strconv.ParseFloat(setting.Value, 64)
 	}
 
-	// 根据商品重量计算运费
-	shippingFee := 0.0
-	if subtotal < 99 && shippingFeeFirstWeight > 0 {
-		shippingFee = shippingFeeFirstWeight
-		if totalWeight > 500 {
-			shippingFee += shippingFeePerGram * (totalWeight - 500)
-		}
-	}
-
 	serviceFee := subtotal * serviceFeeRate / 100
 	tax := subtotal * taxRate / 100
 	channelFee := subtotal * channelFeeRate / 100