Как вывести id главной категории в короткой новости?

function get_parents_category($str) {
	global $cat_info;

	if( !$str ) return;

	$names = array();
	$ids = explode(',', $str);
	foreach ($ids as $id) {
		$parent_id = $cat_info[$id]['parentid'];
		
		while ( $parent_id ) {
		
			$names[] = $cat_info[$parent_id]['name'];

			$parent_id = $cat_info[$parent_id]['parentid'];

			if( $parent_id ) {	
				if( $cat_info[$parent_id]['parentid'] == $cat_info[$parent_id]['id'] ) break;
			}
		}
	}
	
	return implode(', ', $names);
}

$tpl->set( '{parents-category}', get_parents_category($row['category']) );

$row['category'] = intval( $row['category'] );