Modify controller to display regular page with message from bank

commerce_winbank.routing.yml

@@ -3,6 +3,6 @@ commerce_winbank.payment_callback:
   path: '/commerce_winbank/callback'
   defaults:
     _controller: '\Drupal\commerce_winbank\Controller\CallbackController::callback'
-    _title: 'Winbank Payment Controller'
+    _title: 'Winbank Payment'
   requirements:
     _permission: 'access content'

src/Controller/CallbackController.php

@@ -41,8 +41,11 @@ class CallbackController extends ControllerBase {
    * @return Response
    */
   public function callback(Request $request) {
-    $this->processCallback($request);
-    return new Response();
+    $message = $this->processCallback($request);
+    return [
+      '#type' => 'markup',
+      '#markup' => $message,
+    ];
   }
 
 
@@ -58,9 +61,10 @@ class CallbackController extends ControllerBase {
     $hash = $this->calculateHash($request, $order_id, $ticket_result);
     if( $hash !== $hashkey) {
       $this->createPayment($order, $request, $ticket_result, "Unvalidated");
-      return;
+      return "Sorry we were not able to validate your payment";
     }
     $this->createPayment($order, $request, $ticket_result);
+    return $this->getDisplayMessage($request);
   }
 
   /**
@@ -114,4 +118,36 @@ class CallbackController extends ControllerBase {
     );
     return hash_hmac('sha256', $concatValues, $ticket_result['TranTicket'], false);
   }
+
+  /**
+   * Get message .
+   *
+   * @param $request
+   *
+   * @param $IssueNewTicketResult
+   *
+   * @return string
+   */
+  public function getDisplayMessage($request) {
+    $message = $request->get('ResultDescription');
+    if (empty($message)) {
+      $messages = [
+        '00' => 'Completed successfully',
+        '08' => 'Completed successfully',
+        '10' => 'Completed successfully',
+        '16' => 'Completed successfully',
+        '11' => 'Transaction already processed',
+        '05' => 'Declined',
+        '12' => 'Declined',
+        '51' => 'Declined',
+        '34' => 'Lost card / Stolen card / Pick up',
+        '43' => 'Lost card / Stolen card / Pick up',
+        '54' => 'Expired card',
+        '62' => 'Restricted Card',
+        '92' => 'Declined',
+      ];
+      $message = $messages[$request->get('ResponseCode')];
+    }
+    return $message;
+  }
 }