Block Comments Containing Links

<?php
/**
 * Marks any comment containing a URL as spam before it is saved.
 * Returns 'spam' so the comment is caught by the spam queue rather than
 * silently discarded, allowing admin review if needed.
 */
if ( ! function_exists( 'scseed_block_link_comments' ) ) {
    function scseed_block_link_comments( $approved, $commentdata ) {
        if ( 'spam' === $approved ) {
            return $approved; // Already flagged elsewhere — do not override.
        }
        $content = isset( $commentdata['comment_content'] ) ? $commentdata['comment_content'] : '';
        if ( preg_match( '#https?://#i', $content ) ) {
            return 'spam';
        }
        return $approved;
    }
    add_filter( 'pre_comment_approved', 'scseed_block_link_comments', 10, 2 );
}