feat(MED-97): update cart flow for using benefits

lib/services/medusaCart.service.ts

@@ -2,7 +2,7 @@
 
 import { loadCurrentUserAccount } from '@/app/home/(user)/_lib/server/load-user-account';
 import { MontonioOrderHandlerService } from '@/packages/billing/montonio/src';
-import { addToCart, deleteLineItem, retrieveCart } from '@lib/data/cart';
+import { addToCart, deleteLineItem } from '@lib/data/cart';
 import { getCartId } from '@lib/data/cookies';
 import { StoreCartLineItem, StoreProductVariant } from '@medusajs/types';
 import { z } from 'zod';
@@ -87,9 +87,15 @@ export async function handleDeleteCartItem({ lineId }: { lineId: string }) {
 export async function handleNavigateToPayment({
   language,
   paymentSessionId,
+  amount,
+  currencyCode,
+  cartId,
 }: {
   language: string;
   paymentSessionId: string;
+  amount: number;
+  currencyCode: string;
+  cartId: string;
 }) {
   const supabase = getSupabaseServerClient();
   const { account, user } = await loadCurrentUserAccount();
@@ -97,26 +103,21 @@ export async function handleNavigateToPayment({
     throw new Error('Account not found');
   }
 
-  const cart = await retrieveCart();
-  if (!cart) {
-    throw new Error('No cart found');
-  }
-
   const paymentLink =
     await new MontonioOrderHandlerService().getMontonioPaymentLink({
       notificationUrl: `${env().medusaBackendPublicUrl}/hooks/payment/montonio_montonio`,
       returnUrl: `${env().siteUrl}/home/cart/montonio-callback`,
-      amount: cart.total,
-      currency: cart.currency_code.toUpperCase(),
+      amount,
+      currency: currencyCode.toUpperCase(),
       description: `Order from Medreport`,
       locale: language,
-      merchantReference: `${account.id}:${paymentSessionId}:${cart.id}`,
+      merchantReference: `${account.id}:${paymentSessionId}:${cartId}`,
     });
 
   const { error } = await supabase.schema('audit').from('cart_entries').insert({
     operation: 'NAVIGATE_TO_PAYMENT',
     account_id: account.id,
-    cart_id: cart.id,
+    cart_id: cartId,
     changed_by: user.id,
   });
   if (error) {