Added coupon processing. Fixed price calculation

Moonlight/App/Services/Store/StoreOrderService.cs

@@ -52,7 +52,7 @@ public class StoreOrderService
                 .Get()
                 .FirstOrDefault(x => x.Id == coupon.Id);
 
-            if(coupon == null)
+            if (coupon == null)
                 throw new DisplayException("Unsafe value detected. Please reload the page to proceed");
         }
 
@@ -61,13 +61,13 @@ public class StoreOrderService
         if (coupon != null && user.CouponUses.Any(x => x.Coupon.Id == coupon.Id))
             throw new DisplayException("Coupon already used");
 
-        if (coupon != null && coupon.Amount == 0)
+        if (coupon != null && coupon.Amount < 1)
             throw new DisplayException("No coupon uses left");
 
         var price = product.Price * durationMultiplier;
 
         if (coupon != null)
-            price = Math.Round(price * coupon.Percent / 100, 2);
+            price = Math.Round(price - (price * coupon.Percent / 100), 2);
 
         if (user.Balance < price)
             throw new DisplayException("Order is too expensive");
@@ -100,7 +100,7 @@ public class StoreOrderService
         var price = p.Price * durationMultiplier;
 
         if (c != null)
-            price = Math.Round(price * c.Percent / 100, 2);
+            price = Math.Round(price - (price * c.Percent / 100), 2);
 
         //  Calculate duration
         var duration = durationMultiplier * p.Duration;
@@ -108,10 +108,37 @@ public class StoreOrderService
         // Add transaction
         await transactionService.Add(u, -1 * price, $"Bought product '{p.Name}' for {duration} days");
 
-        // Create service
+        // Process coupon if used
-        return await serviceService.Admin.Create(u, p, service =>
+        if (c != null)
         {
-            service.RenewAt = DateTime.UtcNow.AddDays(duration);
+            // Remove one use from the coupon
+            var couponRepo = scope.ServiceProvider.GetRequiredService<Repository<Coupon>>();
+
+            var coupon = couponRepo
+                .Get()
+                .First(x => x.Id == c.Id);
+            
+            coupon.Amount--;
+            couponRepo.Update(coupon);
+
+            // Add coupon use to user
+            var userRepo = scope.ServiceProvider.GetRequiredService<Repository<User>>();
+            
+            var user = userRepo
+                .Get()
+                .Include(x => x.CouponUses)
+                .First(x => x.Id == u.Id);
+            
+            user.CouponUses.Add(new ()
+            {
+                Coupon = coupon
             });
+            
+            userRepo.Update(user);
+        }
+
+        // Create service
+        return await serviceService.Admin.Create(u, p,
+            service => { service.RenewAt = DateTime.UtcNow.AddDays(duration); });
     }
 }

Moonlight/Shared/Views/Store/Order.razor

@@ -75,7 +75,7 @@ TODO: Add 404 here
                         if (SelectedCoupon == null)
                             actualPrice = defaultPrice;
                         else
-                            actualPrice = Math.Round(defaultPrice * SelectedCoupon.Percent / 100, 2);
+                            actualPrice = Math.Round(defaultPrice - (defaultPrice * SelectedCoupon.Percent / 100), 2);
 
                         var currency = ConfigService.Get().Store.Currency;
                     }