/**
* get RMA Items by RMA
*
* @param RMA|string $rma
* @return Ambigous <NULL, unknown>
*/
public static function getByRMA($rma)
{
$rma = $rma instanceof RMA ? $rma : RMA::get(trim($rma));
$rma = $rma instanceof RMA ? $rma : (count($rmas = RMA::getAllByCriteria('RMAId = ?', array(trim($rma)), true, 1, 1)) > 0 ? $rmas[0] : null);
return $rma instanceof RMA ? count($items = self::getAllByCriteria('RMAId = ?', array($rma->getId()), true)) > 0 ? $items : null : null;
}
