public function isValid()
    {
        if (!$this->oxorderfiles__oxmaxdownloadcount->value || ($this->oxorderfiles__oxdownloadcount->value < $this->oxorderfiles__oxmaxdownloadcount->value)) {
            if (!$this->oxorderfiles__oxlinkexpirationtime->value && !$this->oxorderfiles__oxdownloadxpirationtime->value) {
                return true;
            } else {
                $sNow = \OxidEsales\Eshop\Core\Registry::getUtilsDate()->getTime();
                $iTimestamp = strtotime($this->oxorderfiles__oxvaliduntil->value);
                if (!$iTimestamp || ($iTimestamp > $sNow)) {
                    return true;
                }
            }
        }

        return false;
    }