HTML Mini parser

class html_parser
{
    public static function trim_multichar($str, $chars) {
        foreach (str_split($chars) as $char) {
            $str = trim($str, $char);
        }

        return $str;
    }

    public static function trim_all($array, $chars) {
        foreach ($array as $key => $el) {
            $array[$key] = self::trim_multichar($el, $chars);
        }

        return $array;
    }

    public static function parse_tpl($html, $data = array()) {
        // functions
        $matches = array();
        preg_match('/\s{%(.*?)%}\s/', $html, $matches);
        while (count($matches)) {
            $match = trim($matches[0]);
            $params = self::trim_multichar($match, "{%}% ");
            $params = explode('|', $params);
            $f = trim($params[0]);
            if (function_exists($f)) {
                if (count($params) > 1) {
                    unset($params[0]);
                    $params = array_merge($params, array());
                }

                $ret = call_user_func_array($f, $params);
                if ($ret !== false) {
                    $html = str_replace($match, $ret, $html);
                }
            } else {
                break;
            }

            preg_match('/(\s{%.*?%}\s)/', $html, $matches);
        }

        // variables from $data
        $matches = array();
        preg_match('/{{(.*?)}}/', $html, $matches);

        while (count($matches)) {
            $match = trim($matches[0]);
            $key = self::trim_multichar($match, "{} ");
            $replace = '';
            if (isset($data[$key])) {
                $replace = $data[$key];
            }
            $html = str_replace($match, $replace, $html);

            preg_match('/{{(.*?)}}/', $html, $matches);
        }

        return $html;
    }
}