Implementierung - SEO - 15.08.2025

src/services/gtm.ts

@@ -6,19 +6,63 @@
 declare global {
   interface Window {
     dataLayer: any[];
+    gtmLoaded?: boolean;
   }
 }
 
+// GTM ID
+const GTM_ID = 'GTM-NQK6ZV7N';
+
 // Initialisiere dataLayer falls nicht vorhanden
 if (typeof window !== 'undefined' && !window.dataLayer) {
   window.dataLayer = [];
 }
 
+// Prüft, ob Marketing-Cookies aktiviert sind
+const isMarketingEnabled = (): boolean => {
+  try {
+    const cookieSettings = localStorage.getItem('cookieSettings');
+    if (!cookieSettings) return false;
+    
+    const settings = JSON.parse(cookieSettings);
+    return settings.marketing === true || settings.analytics === true;
+  } catch (error) {
+    console.error('Error checking cookie settings:', error);
+    return false;
+  }
+};
+
+// Lädt Google Tag Manager nur nach Zustimmung
+export const loadGoogleTagManager = (): void => {
+  if (!isMarketingEnabled() || window.gtmLoaded) {
+    return;
+  }
+
+  // GTM Script laden
+  const script = document.createElement('script');
+  script.innerHTML = `
+    (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
+    new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
+    j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
+    'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
+    })(window,document,'script','dataLayer','${GTM_ID}');
+  `;
+  document.head.appendChild(script);
+
+  // GTM noscript iframe
+  const noscript = document.createElement('noscript');
+  noscript.innerHTML = `<iframe src="https://www.googletagmanager.com/ns.html?id=${GTM_ID}"
+    height="0" width="0" style="display:none;visibility:hidden"></iframe>`;
+  document.body.insertBefore(noscript, document.body.firstChild);
+
+  window.gtmLoaded = true;
+};
+
 /**
  * Push event to GTM dataLayer
  */
 export const pushToDataLayer = (data: Record<string, any>) => {
-  if (typeof window !== 'undefined' && window.dataLayer) {
+  if (typeof window !== 'undefined' && window.dataLayer && isMarketingEnabled()) {
     window.dataLayer.push(data);
   }
 };