Sensei Display course certificate on quiz pages

functions.php

add_action( 'sensei_before_main_content', 'senseiBeforeMainContent', 10 );
 
function senseiBeforeMainContent() {
    if( !is_singular('quiz') ) return;
    global $post, $current_user;
 
    if(isset($post->post_parent) && $post->post_parent != 0) {
      $lessonPost = get_post($post->post_parent);
 
      $courseID = get_post_meta($lessonPost->ID, '_lesson_course', true);
 
      $availableCertificates = get_posts(array(
        'post_type' => 'certificate',
        'meta_query' => array(
            array(
                'key'   => 'course_id',
                'value' => $courseID
            ),
            array(
                'key'   => 'learner_id',
                'value' => $current_user->ID
            )
        ),
      ));
 
      if(!empty($availableCertificates)) {
        foreach($availableCertificates as $availableCertificate) {
          echo '<a class="sensei-certificate-link" href="' . $availableCertificate->guid . '" target="_blank">' . __("View Certificate") . '</a>';
        }
      }
    }
  }