defender::verify_date PHP Method

    protected function verify_date()
    {
        global $locale;
        if ($this->field_value) {
            $dateParams = strtotime($this->field_value);
            $dateParams = getdate($dateParams);
            if (checkdate($dateParams['mon'], $dateParams['mday'], $dateParams['year'])) {
                switch ($this->field_config['type']) {
                    case "timestamp":
                        $secured = (int) mktime($dateParams['hours'], $dateParams['minutes'], $dateParams['seconds'], $dateParams['mon'], $dateParams['mday'], $dateParams['year']);
                        return $secured;
                        break;
                    case "date":
                        return (string) $dateParams['year'] . "-" . $dateParams['mon'] . "-" . $dateParams['mday'];
                        break;
                }
            } else {
                $this->stop();
                self::setInputError($this->field_name);
                addNotice('info', sprintf($locale['df_404'], $this->field_config['title']));
            }
        }
        return (string) $this->field_default;
    }