Метод вызывается перед получением всех скидок

AddEventHandler("catalog", "OnGetDiscount","OnGetDiscount");


    /**
     * Вызывается в методе CCatalogDiscount::GetDiscount перед получением всех скидок
     * @return bool true
     */
    function OnGetDiscount($intProductID, $intIBlockID, $arCatalogGroups,
        $arUserGroups, $strRenewal, $siteID, $arDiscountCoupons, $boolSKU, $boolGetIDS){
        //error_log(print_r($_REQUEST,true), 3, $_SERVER["DOCUMENT_ROOT"] . "/error_log.txt");
        if($_REQUEST['action']!='addProductToBasket') {
            error_log('no'.PHP_EOL, 3, $_SERVER["DOCUMENT_ROOT"] . "/error_log.txt");
            return false;
        }
        else {
            //error_log($_REQUEST['action'], 3, $_SERVER["DOCUMENT_ROOT"] . "/error_log.txt");
            return true;
        }
    }

    AddEventHandler("sale", "OnSaleComponentOrderResultPrepared","OnSaleComponentOrderResultPrepared");
    use Bitrix\Highloadblock as HL;
    function OnSaleComponentOrderResultPrepared($order, &$arUserResult, $request,&$arParams,&$arResult){
        error_log('5', 3, $_SERVER["DOCUMENT_ROOT"] . "/error_log.txt");
        //if($request->isAdminSection())
            //return true;
        /*Скидки через HL*/

        Bitrix\Main\Loader::includeModule('highloadblock');

        $hlBlockId = 3;
        $hlblock = HL\HighloadBlockTable::getById($hlBlockId)->fetch();
        $entity = HL\HighloadBlockTable::compileEntity($hlblock);
        $dataClass = $entity->getDataClass();

        $basket = $order->getBasket();
        foreach ($arResult['BASKET_ITEMS'] as &$item){
            $result5 = $dataClass::getList([//запрос скидки из HighloadBlock
                "select" => array('UF_PROD_ID','UF_DISC_VAL'),
                "order" => array("ID" => "DESC"),
                "filter" => array('UF_PROD_ID' => $item['PRODUCT_ID'])
            ]);
            //die($item['PRODUCT_ID']);
            if($arElement2 = $result5->fetch())
                $discval = $arElement2['UF_DISC_VAL'];

            if(!empty($discval) && $discval>0) {
                $discdiff = (floatval($item['BASE_PRICE'])*floatval($discval))/100;
                $discprice = floatval($item['BASE_PRICE'])-floatval($discdiff);

                $item["DISCOUNT_PRICE"] = $discprice;
                $item["DISCOUNT_PRICE_PERCENT"] = $discval;
                $item["DISCOUNT_PRICE_PERCENT_FORMATED"] = Bitrix\Sale\PriceMaths::roundPrecision($item["DISCOUNT_PRICE_PERCENT"])."%";
                $item["PRICE_FORMATED"] = SaleFormatCurrency($item["DISCOUNT_PRICE"], $order->getCurrency());

                //Установка цены у товара
                $basketItem = $basket->getItemByBasketCode($item['ID']);
                $basketItem->setField('CUSTOM_PRICE', 'Y');
                $basketItem->setField('PRICE', $discprice);
                $basketItem->setField('DISCOUNT_PRICE', $discprice);
            }
        }
        $order->setFieldNoDemand('PRICE_DELIVERY', 0);//исправление цены доставки

        $order->refreshData();

        $payment = $order->getPaymentCollection()[0];
        $payment->setField('SUM', $order->getPrice());//Изменение суммы к оплате

        $arResult["ORDER_PRICE"] = $basket->getPrice();
        $arResult["ORDER_PRICE_FORMATED"] = SaleFormatCurrency($basket->getPrice(), $order->getCurrency());

        $arResult["ORDER_TOTAL_PRICE"] = $order->getPrice();
        $arResult["ORDER_TOTAL_PRICE_FORMATED"] = SaleFormatCurrency($order->getPrice(), $order->getCurrency());

    }