add error handling

src/components/easycredit-checkout/easycredit-checkout.tsx

@@ -160,6 +160,9 @@ export class EasycreditCheckout {
       this.modal.close()
     })
 
+    this.submitButtonClicked = true
+
+    this.addErrorHandler()
     this.el.dispatchEvent(new CustomEvent('submit', {
       bubbles    : true,
       cancelable : true,
@@ -170,6 +173,34 @@ export class EasycreditCheckout {
     }))
   }
 
+  addErrorHandler () {
+    let time = 4
+
+    let timeout = window.setTimeout(() => {
+      this.alert = 'Leider ist eine Zahlung mit easyCredit derzeit nicht möglich. Bitte verwenden Sie eine andere Zahlungsart oder wenden Sie sich an den Händler.'
+      this.modal.close()
+      console.error('No event handler handled the submit event of <easycredit-checkout> within ' + time +' seconds. Please check the integration.')
+      sendFeedback(this, { component: 'EasycreditCheckout', action: 'error' })
+    }, time * 1000)
+
+    // check for any request or page unload to determine if any event handler was reacting on the button click
+    var observer = new PerformanceObserver(function (batch) {
+      if (batch.getEntries()
+          .filter(entry => entry.initiatorType === 'xmlhttprequest' || entry.initiatorType === 'fetch')
+          .filter(entry => !entry.name.match(/\/api\/webcomponents\/v3\/feedback/))
+          .length > 0
+      ) {
+        window.clearTimeout(timeout)
+        observer.disconnect()
+      }
+    });
+    observer.observe({ type: 'resource' });
+
+    window.onbeforeunload = function () {
+      window.clearTimeout(timeout)
+    }
+  }
+
   getPaymentPlan () {
     if (this.alert) {
       return false