WordPress Plugin: nexGEN Gallery Image clicks to GA/GTM

nexGENGalleryImageClick.php

<?php

/**
* Plugin Name: WP NextGENGalery Image Clicks
*/

add_action('wp_footer', 'nextGENGallery_enqueue_custom_js');
function nextGENGallery_enqueue_custom_js() {
 if(is_page()) {
  global $post;
  $post_data = get_post($post->post_parent);
  $parent_slug = $post_data->post_name;
  $current_slug = $post->post_name;

  $parentPage = ucwords(str_replace('-', ' ', $parent_slug));
  $currentPage = ucwords(str_replace('-', ' ', $current_slug));

   if($parent_slug == 'tattoo-designs') {
    echo "
    <script>
      const nGGallery = document.querySelectorAll('.ngg-gallery-thumbnail a img');
      const getParentPageName = '". $parentPage ."'
      const getCurrentPageName = '". $currentPage ."'
      Array
        .from(nGGallery)
          .forEach(el => el.addEventListener('click', () => {
            const image = el.getAttribute('src');
            const imageSplit = image.split('/');
            const imageSlashCount = imageSplit.length;
            console.log(imageSplit[imageSlashCount-1]);
            console.log(getParentPageName);

            // if you use GA snippet on your website
            // gtag('event', 'click', {
            //   'event_category': 'image Click: ' + getParentPageName,
            //   'event_label': imageSplit[imageSlashCount-1],
            //   'value': 1
            // });

            // if you use GTM snippet on your website
            window.dataLayer = window.dataLayer || [];
            window.dataLayer.push({
              'event': 'imageclick',
              'eventParentPage': getParentPageName,
              'eventCurrentPage': getCurrentPageName,
              'eventImageSrc': imageSplit[imageSlashCount-1],
            });

          })
      );
    </script>";
  }
 }
}
?>