Unique OrderId Validation for Coupon Use

resources/Affiliate&Coupon/Coupon/CouponController.js

@@ -286,21 +286,52 @@ export const usedCoupon = async (req, res) => {
     const couponData = await AffiliateModel.findOne({
       coupon_code: coupon_code,
     });
+    //order exists or not
 
-    // Check if the coupon exists
     if (!couponData) {
+      // Check if the coupon exists
       return res.status(404).json({
         success: false,
         message: "Coupon not found",
       });
     }
+    // Check if orderId is unique
+    try {
+      const isOrderIdUnique = await AffiliateModel.find(
+        {},
+        {
+          coupon_used_history: 1,
+        }
+      );
 
+      let orderIdFound = false;
+
+      isOrderIdUnique.forEach((data) => {
+        data.coupon_used_history.forEach((subItem) => {
+          if (subItem.orderId == orderId) {
+            orderIdFound = true;
+          }
+        });
+      });
+
+      if (orderIdFound) {
+        return res.status(400).json({
+          success: false,
+          message: "Error: OrderId already used",
+        });
+      }
+    } catch (error) {
+      console.error(error);
+      return res.status(500).json({
+        success: false,
+        message: "Internal server error",
+      });
+    }
+    //If not unique then create
     const {
       valid_till,
       is_coupon_active,
-      total_earning,
       is_affiliate_active,
-      coupon_claimed,
       affiliate_discount_amount,
       _id,
     } = couponData;