How to get OrderHed to calculate discount after updating all lines?

We have REST setups that create new Sales Orders that don’t include customer discounts.
I am trying to create a data directive in OrderHed update that will update OrderHed and OrderDtls for a SalesOrder if the Customer’s discount wasn’t added to an order. So far I can update all OrderDtls and fields in OrderHed, but can’t figure out how to get OrderHed to recalculate the totals with the new discount.

Here is my code:

using(var txScope = IceContext.CreateDefaultTransactionScope())
    // Current ttOrderHed Row
    var tempOrderHed = ttOrderHed.FirstOrDefault();
    string tqhCompany = tempOrderHed.Company;
    int tqhOrderNum = tempOrderHed.OrderNum;
    int tqhCustNum = tempOrderHed.CustNum;
    string tqhRowMod = tempOrderHed.RowMod;
    // Empty Varibles to Use Later
    string companyNum = "";
    int orderNum = 0;
    int custNum = 0;
    decimal custDisc = 0.00m;
    decimal orderDisc = 0.00m;
    string sysRowID = "";
    // Look Up OrderHed in Database - Confirm Order's in Company #####
    if( tqhCompany == "#####" )
        companyNum = tempOrderHed.Company.ToString();
        orderNum = Convert.ToInt32(tempOrderHed.OrderNum);
        custNum = Convert.ToInt32(tempOrderHed.CustNum);
        // Create Db var orderHed and Link to OrderHed in Db
        var orderHed = Db.OrderHed.Where(oh => oh.Company == companyNum && oh.OrderNum == orderNum && oh.CustNum == custNum).FirstOrDefault();
        // Make sure there is a valid OrderHed in orderHed
        if(orderHed != null)
            // Get OrderHed Discount & SysRowID of OrderHed
            orderNum = Convert.ToInt32(orderHed.OrderNum);
            orderDisc = Convert.ToDecimal(orderHed.DiscountPercent);
            sysRowID = orderHed.SysRowID.ToString();
        // Create Db var customerDB and Link to Customer in Db
        var customerDB = Db.Customer.Where(cdb => cdb.Company == companyNum && cdb.CustNum == custNum).FirstOrDefault();
        // Make sure there is a valid Customer in customerDB
        if(customerDB != null)
            // Get Customer Discount for the Customer
            custDisc = Convert.ToDecimal(customerDB.DiscountPercent);
        // If OrderHed Discount Percent doesn't equal Customer Discount Percent run the below code
        if(orderDisc != custDisc)
            var docTotal = Convert.ToDecimal(orderHed.DocTotalCharges);
            var discount = Convert.ToDecimal(custDisc / 100);
            var discountTotal = Convert.ToDecimal(docTotal * discount);
            orderHed.DiscountPercent = Convert.ToDecimal(custDisc);
            orderHed.DocTotalDiscount = Convert.ToDecimal(discountTotal);
            var bo = ServiceRenderer.GetService<Erp.Contracts.SalesOrderSvcContract>(Db);
            // Run foreach function to check and update discount percentage for each OrderDtl Line
            foreach(var orderDtl in Db.OrderDtl.Where(od => od.Company == orderHed.Company && od.OrderNum == orderHed.OrderNum).OrderBy(ol => ol.OrderLine))
                // Empty Varibles
                string companyNumber = "";
                int ordNum = 0;
                int orderLine = 0;
                int customerNum = 0;
                decimal lineDisc = 0.00m;
                // Make sure there is a valid OrderDtl Line in orderDtl
                if(orderDtl != null)
                    // Set Varibles Values
                    companyNumber = orderDtl.Company.ToString();
                    ordNum = Convert.ToInt32(orderDtl.OrderNum);
                    orderLine = Convert.ToInt32(orderDtl.OrderLine);
                    customerNum = Convert.ToInt32(orderDtl.CustNum);
                    lineDisc = Convert.ToDecimal(orderDtl.DiscountPercent);
                    // If Customer Discount Percent doesn't equal OrderDtl Line Discount Percent update var lineDisc to equal var custDisc
                    if(lineDisc != custDisc)
                        lineDisc = Convert.ToDecimal(custDisc);
                        int serialNum = (Convert.ToInt32(orderDtl.OrderLine) - 1);
                        var ds = bo.GetByID(ordNum);
                        // Create Before Image
                        var origRow = ds.OrderDtl.NewRow();
                        BufferCopy.Copy(orderDtl, origRow);
                        // Update Record
                        ds.OrderDtl[serialNum].OrderLine = Convert.ToInt32(orderLine);
                        ds.OrderDtl[serialNum].DiscountPercent = Convert.ToDecimal(lineDisc);
                        ds.OrderDtl[serialNum].RowMod = "U";
                        bo.ChangeDiscountPercent(ref ds);
                        ds.OrderDtl[serialNum].RowMod = "U";
                        ds.OrderDtl[serialNum].DiscountPercent = Convert.ToDecimal(lineDisc);
                        ds.OrderDtl[serialNum].OrderLine = Convert.ToInt32(orderLine);
                        bo.Update(ref ds);
                        // Update Discount Percentage for Each OrderDtl
    ////////// Now To Test :)

The logic looks good, so I’m not sure why it is not working. If anything maybe get a client trace of doing this through the erp client and see if maybe a call is missing.

You can also try UpdateOrderDtlDiscountPercent, this is used when you enter a new discount at the header level and the UI asks if you want to apply it to all the lines.

@Jonathan thanks for the suggestion! I have tried “ApplyOrderHedDiscountToLines” with no success. In the documentation “UpdateOrderDtlDiscountPercent” has two parameters, see below:

   int orderNum,
   string orderLines

What do I use for the second parameter, string orderLines?

A string with the line numbers to apply the discount, separated by ~

So something like “1~2~3”

Is there a way to just specify all? Rather than looking up all lines for the Sales Order and writing something to recreate that format dynamically? That seems pretty static otherwise. Just curious.