private function calculateDiscounts()
 {
     $paymentDiscount = new PaymentDiscount();
     $paymentMethodHelper = new PaymentMethodHelper();
     $payment_method = $paymentMethodHelper->getById(Tools::getValue('payment-method'));
     $cart = $this->context->cart;
     if (PaymentMethodHelper::isCard($payment_method) && Tools::getValue('card-installment') == 1) {
         $paymentDiscount->apply($cart, 'DESCONTO_CREDITO', $this->context);
     } else {
         if (PaymentMethodHelper::isTEF($payment_method)) {
             $paymentDiscount->apply($cart, 'DESCONTO_TEF', $this->context);
         } else {
             if (PaymentMethodHelper::isBankSlip($payment_method)) {
                 $paymentDiscount->apply($cart, 'DESCONTO_BOLETO', $this->context);
             }
         }
     }
     $totalDiscouts = $paymentDiscount->getAmountOrderDiscounts($cart);
     return $totalDiscouts;
 }