The Net amount of Bill will be same whether discount given before S.T or after that. We will not be affected. If More S.T Charged, same amount will be given as discount and if Discount given before S.T then S.T will be charged on the reduced amount. Department may have problem in that case. I think S.T before Discount will be more safe than Discount before S.T.
Here My issue is only the amount to be considered for TDS calculation.