private function calculateShipping($shipping_option) { $numDisks = 0; $shippingCharge = 0.0; $itemCount = OrdersController::getCountOfItems(); if ($shipping_option == 'ship_separately') { $shippingCharge += OrdersController::calculateShippingFee($itemCount['CD']['count']); $shippingCharge += OrdersController::calculateShippingFee($itemCount['DVD']['count']); } else { switch ($shipping_option) { case 'ship_together': $numDisks = $itemCount['CD']['count'] + $itemCount['DVD']['count']; break; case 'ship_dvd': case 'ship_dvd_only': $numDisks = $itemCount['DVD']['count']; break; case 'ship_cd': $numDisks = $itemCount['CD']['count']; break; } $shippingCharge = OrdersController::calculateShippingFee($numDisks); } return $shippingCharge; }