Honeypot for Wordpress Comments - hide and use the url field for spam protection

honeypot-for-wordpress-comments.php

/**
 *
 * @author    Chris Martens
 * @link      https://chris-martens.com/
 * @link      https://chris-martens.com/blog/honeypot-fuer-kommentarfunktion/
 * @snippet   Comments without URL Field. 
 *
 */

/** Reduce spam comments */

function chrmrtns_remove_comment_author_link( $return, $author, $comment_ID ) {
            return $author;
}
add_filter( 'get_comment_author_link', 'chrmrtns_remove_comment_author_link', 10, 3 );

function chrmrtns_remove_comment_author_url() {
    return false;
}
add_filter( 'get_comment_author_url', 'chrmrtns_remove_comment_author_url');


/** Remove website field - uncomment filter if you want to use this */

function chrmrtns_remove_website_field($fields) {
   unset($fields['url']);
   return $fields;
}
//add_filter('comment_form_default_fields', 'chrmrtns_remove_website_field', 60);


/** Honeypot Check - instead of hiding this, you can send it to trash or spam */

function chrmrtns_hide_website_field($fields) {
    // Hide the URL field using inline CSS
    $fields['url'] = '<div style="display: none;">' . $fields['url'] . '</div>';
    return $fields;
}
add_filter('comment_form_default_fields', 'chrmrtns_hide_website_field', 60);

function chrmrtns_check_comment_for_honeypot( $commentdata ) {
    if ( !empty($_POST['url']) ) {
        // Move the comment to trash instead of dying
        add_filter('pre_comment_approved', 'chrmrtns_send_comment_to_trash');
    }
    return $commentdata;
}

/** Return either trash or spam */
function chrmrtns_send_comment_to_trash( $approved ) {
    // 'trash' moves the comment to trash
    // 'spam' moves the comment to spam
    return 'trash';
}

add_filter( 'preprocess_comment', 'chrmrtns_check_comment_for_honeypot' );