Discount information in CIS Tax Service

Hello!

We're developing a CIS tax module to calculate tax using our external tax calculation engine. We've been able to complete most of it already with no problems.

Right now, we want to add discounts to the calculation but we haven't found any information regarding discounts in the CIS object models. Running some tests, we found that the discount is applied to the total and then divided in each unit price. As a result, the unit price is then modified and sent to CIS. So when we pick up the CIS unit price, it differs from the original unit price (as it just had discounts applied to it).

Is there a way to receive the discount amounts in the CIS service and to not apply it to each line's unit price?

Thanks!