Shipment::convert

public function convert($data)
{
	$result = "";

	if(!is_array($data))
		throw new ArgumentTypeException("data", "array");

	foreach($data as $item)
	{
		if(!isset($item["ORDER_ID"])
			|| !isset($item["ORDER_LINE_ITEM_ID"])
			|| !isset($item["DELIVERY_NAME"])
			|| !isset($item["TRACKING_NUMBER"])
		)
		{
			throw new SystemException("Wrong structure of item in Shipment::convert()");
		}

		$result .= "tn".
			"tt".$item["ORDER_ID"]."n".
			"tt".$item["ORDER_LINE_ITEM_ID"]."n".
			//"tt".$data["SHIPPED_TIME"]."n".
			 "ttn".
			"ttt".$item["DELIVERY_NAME"]."n".
			"ttt".$item["TRACKING_NUMBER"]."n".
			"ttn".
			"tn";
	}

	return $result;
}