Function to set vendor pricing in item record

The following code is used to add vendor and vendor pricing to the item record.

function setvendorCurrency(itemRec,vendorId,itemDetails){   
try {
        itemRec.selectNewLine({
            sublistId: 'itemvendor'
        });
        itemRec.setCurrentSublistValue({
            sublistId: 'itemvendor',
            fieldId: 'vendor',
            value: vendorId
        });
        if (key == 'custom_item_vendor') {
            itemRec.setCurrentSublistValue({
                sublistId: 'itemvendor',
                fieldId: 'vendorcode',
                value: itemDetails.vendorCode
            });
        }
        // Loading the itemVendorPrice Sublist subrecord
        let itemVendorPriceRec = itemRec.getCurrentSublistSubrecord({
            sublistId: 'itemvendor',
            fieldId: 'itemvendorprice'
        });
        // Select the itemVendorPrice Line
        itemVendorPriceRec.selectNewLine({
            sublistId: "itemvendorpricelines"
        });
        if (key == 'custom_item_vendor') {
            itemVendorPriceRec.setCurrentSublistValue({
                sublistId: 'itemvendorpricelines',
                fieldId: 'vendorcurrency',
                value: itemDetails.vendor_Currency
            });
            // Setting vendor purchase price
            itemVendorPriceRec.setCurrentSublistValue({
                sublistId: "itemvendorpricelines",
                fieldId: "vendorprice",
                value: itemDetails.vendor_Price
            });
        } else {
            //Getting the currency and purchase price
            itemVendorPriceRec.setCurrentSublistValue({
                sublistId: 'itemvendorpricelines',
                fieldId: 'vendorcurrency',
                value: 1
            });
            // Setting vendor purchase price
            itemVendorPriceRec.setCurrentSublistValue({
                sublistId: "itemvendorpricelines",
                fieldId: "vendorprice",
                value: itemDetails[key]
            });
        }
        itemVendorPriceRec.commitLine({
            sublistId: "itemvendorpricelines"
        });
        // commit item vendor
        itemRec.commitLine({sublistId: "itemvendor"});
    } catch (e) {
        log.error({
            title: e.name,
            details: e
        });
    }
}