feat: Implement default payment method for pickup and enhance payment method handling in CartTab and PaymentMethodSelector components

src/components/profile/CartTab.js

@@ -224,6 +224,15 @@ class CartTab extends Component {
     const newDeliveryMethod = this.normalizeDeliveryMethod(event.target.value);
     const deliveryCost = this.orderService.getDeliveryCost();
 
+    // Pickup should default to in-store payment.
+    if (newDeliveryMethod === "Abholung") {
+      this.setState({
+        deliveryMethod: newDeliveryMethod,
+        paymentMethod: "cash",
+      });
+      return;
+    }
+    
     // Get optimal payment method for the new delivery method
     const optimalPaymentMethod = CheckoutValidation.getOptimalPaymentMethod(
       newDeliveryMethod,

src/components/profile/CheckoutValidation.js

@@ -80,8 +80,13 @@ class CheckoutValidation {
       return "wire";
     }
     
-    // Prefer stripe when available and meets minimum amount
+    // Pickup defaults to in-store payment
-    if (deliveryMethod === "DHL" || deliveryMethod === "DPD" || deliveryMethod === "Abholung") {
+    if (deliveryMethod === "Abholung") {
+      return "cash";
+    }
+
+    // Prefer wire for shippable delivery methods
+    if (deliveryMethod === "DHL" || deliveryMethod === "DPD") {
       return "wire";/*stripe*/
     }
     
@@ -96,9 +101,10 @@ class CheckoutValidation {
     const subtotal = cartItems.reduce((total, item) => total + item.price * item.quantity, 0);
     const totalAmount = subtotal + deliveryCost;
 
-    // Reset payment method if it's no longer valid
+    // Reset "Nachnahme" when delivery is not DHL.
+    // For pickup, default to in-store payment.
     if (deliveryMethod !== "DHL" && paymentMethod === "onDelivery") {
-      newPaymentMethod = "wire";
+      newPaymentMethod = deliveryMethod === "Abholung" ? "cash" : "wire";
     }
 
     // Allow stripe for DHL, DPD, and Abholung delivery methods, but check minimum amount

src/components/profile/PaymentMethodSelector.js

@@ -1,4 +1,4 @@
-import React, { useEffect, useCallback } from "react";
+import React, { useEffect, useCallback, useRef } from "react";
 import { Box, Typography, Radio } from "@mui/material";
 import { withI18n } from "../../i18n/withTranslation.js";
 
@@ -7,6 +7,7 @@ const PaymentMethodSelector = ({ paymentMethod, onChange, deliveryMethod, onDeli
   // Calculate total amount
   const subtotal = cartItems.reduce((total, item) => total + item.price * item.quantity, 0);
   const totalAmount = subtotal + deliveryCost;
+  const previousDeliveryMethodRef = useRef(deliveryMethod);
   
   // Handle payment method changes with automatic delivery method adjustment
   const handlePaymentMethodChange = useCallback((event) => {
@@ -19,14 +20,33 @@ const PaymentMethodSelector = ({ paymentMethod, onChange, deliveryMethod, onDeli
       }
     }
 
+    // If "Nachnahme" is selected, force delivery method to "DHL"
+    if (selectedPaymentMethod === "onDelivery" && deliveryMethod !== "DHL") {
+      if (onDeliveryMethodChange) {
+        onDeliveryMethodChange({ target: { value: "DHL" } });
+      }
+    }
+    
     onChange(event);
   }, [deliveryMethod, onDeliveryMethodChange, onChange]);
 
-  // Handle delivery method changes - auto-switch to stripe when DHL/DPD is selected
+  // Handle delivery method changes - auto-switch to wire when DHL/DPD is selected
   useEffect(() => {
-    if ((deliveryMethod === "DHL" || deliveryMethod === "DPD") && paymentMethod === "cash") {
+    const previousDeliveryMethod = previousDeliveryMethodRef.current;
+    const deliveryMethodChanged = previousDeliveryMethod !== deliveryMethod;
+
+    if (deliveryMethodChanged && (deliveryMethod === "DHL" || deliveryMethod === "DPD") && paymentMethod === "cash") {
       handlePaymentMethodChange({ target: { value: "wire" /*stripe*/ } });
     }
+
+    previousDeliveryMethodRef.current = deliveryMethod;
+  }, [deliveryMethod, paymentMethod, handlePaymentMethodChange]);
+
+  // If switching to pickup while "Nachnahme" is selected, default to in-store payment
+  useEffect(() => {
+    if (deliveryMethod === "Abholung" && paymentMethod === "onDelivery") {
+      handlePaymentMethodChange({ target: { value: "cash" } });
+    }
   }, [deliveryMethod, paymentMethod, handlePaymentMethodChange]);
 
   // Auto-switch to cash when total amount is 0
@@ -75,7 +95,7 @@ const PaymentMethodSelector = ({ paymentMethod, onChange, deliveryMethod, onDeli
       id: "onDelivery",
       name: t ? t('payment.methods.cashOnDelivery') : "Nachnahme",
       description: t ? t('payment.methods.cashOnDeliveryDescription') : "Bezahlen Sie bei Lieferung (8,99 € Aufschlag)",
-      disabled: totalAmount === 0 || deliveryMethod !== "DHL",
+      disabled: totalAmount === 0,
       icons: ["/assets/images/cash.png"],
     },
     {