feat: 订单自动过期-查看时检查并取消超时订单，收银台倒计时结束自动取消

backend/internal/api/handlers/order.go

@@ -4,6 +4,7 @@ import (
 	"math"
 	"net/http"
 	"strconv"
+	"time"
 
 	"sale/internal/models"
 	"sale/internal/schemas"
@@ -91,6 +92,41 @@ func NewOrderHandler() *OrderHandler {
 	return &OrderHandler{}
 }
 
+func checkOrderExpired(order *models.Order) {
+	if order.Status != models.OrderStatusPendingPayment || order.PaymentExpiresAt == nil {
+		return
+	}
+	if time.Now().After(*order.PaymentExpiresAt) {
+		tx := utils.DB.Begin()
+		tx.Model(order).Update("status", models.OrderStatusCancelled)
+		for _, item := range order.OrderItems {
+			var inventory models.Inventory
+			if err := tx.Where("product_id = ?", item.ProductID).First(&inventory).Error; err == nil {
+				tx.Model(&inventory).UpdateColumn("quantity", inventory.Quantity+item.Quantity)
+			}
+			var product models.Product
+			if err := tx.First(&product, item.ProductID).Error; err == nil {
+				if product.RequireCredit {
+					tx.Model(&models.User{}).Where("id = ?", order.UserID).
+						UpdateColumn("purchase_credits", utils.DB.Raw("purchase_credits + ?", product.CreditCost*item.Quantity))
+				}
+				if product.CreditReward > 0 {
+					tx.Model(&models.User{}).Where("id = ?", order.UserID).
+						UpdateColumn("purchase_credits", utils.DB.Raw("purchase_credits - ?", product.CreditReward*item.Quantity))
+				}
+			}
+		}
+		tx.Commit()
+		order.Status = models.OrderStatusCancelled
+	}
+}
+
+func checkOrdersExpired(orders []models.Order) {
+	for i := range orders {
+		checkOrderExpired(&orders[i])
+	}
+}
+
 func (h *OrderHandler) List(c *gin.Context) {
 	userID := c.GetUint("user_id")
 	role, _ := c.Get("role")
@@ -107,6 +143,8 @@ func (h *OrderHandler) List(c *gin.Context) {
 	query.Preload("OrderItems.Product").Preload("ShippingAddress").
 		Order("created_at DESC").Find(&orders)
 
+	checkOrdersExpired(orders)
+
 	c.JSON(http.StatusOK, gin.H{"data": orders})
 }
 
@@ -129,6 +167,8 @@ func (h *OrderHandler) GetByID(c *gin.Context) {
 		return
 	}
 
+	checkOrderExpired(&order)
+
 	c.JSON(http.StatusOK, gin.H{"data": order})
 }
 
@@ -400,6 +440,8 @@ func (h *OrderHandler) AdminList(c *gin.Context) {
 	utils.DB.Preload("OrderItems.Product").Preload("ShippingAddress").Preload("User").
 		Order("created_at DESC").Offset(offset).Limit(pageSize).Find(&orders)
 
+	checkOrdersExpired(orders)
+
 	totalPages := int(math.Ceil(float64(total) / float64(pageSize)))
 	c.JSON(http.StatusOK, gin.H{
 		"data": orders,