ACF Validate Facebook Field

acf-validate-facebook-url-field.php

<?php
/*
 * Validate Facebook URL field
 * URL field must be named "facebook_video_url" or you can change is in the filter below.
 * Source: https://www.advancedcustomfields.com/resources/acf-validate_value/
*/
function acf_validate_facebook_url( $valid, $value, $field, $input ){
  // If already not valid, then exit
  if( !$valid ) {
    return $valid;
  }
  // Check if the $value is a Facebook video URL
  // REGEX Source: https://gist.github.com/mul14/44579d0ab523ab33d9f0
  $video = preg_match('/^http(?:s?):\/\/(?:www\.|web\.|m\.)?facebook\.com\/([A-z0-9\.]+)\/videos(?:\/[0-9A-z].+)?\/(\d+)(?:.+)?$/',$value);
  if( !$video ) {
    // If not value, then this error:
    $valid = 'Must be a Facebook Video URL.';
  }
  // Return the result
  return $valid;
}
add_filter('acf/validate_value/name=facebook_video_url', 'acf_validate_facebook_url', 10, 4);
?>