Being able to apply order discount only to products in the cart that are not on sale.

I want to have an order discount of 5% for all orders above 50€. However, these 5% should only be deducted from products that are not on sale. If products in the cart are on sale, they add up to the cart amount but they are not deducted. do you understand what I want?

For example:

Product A: 45€ (discounted SKU, normally 55€)

Product B: 8€

Total cart: 53€

Disocunt of 5% only apply to the 8€: 0,40€

Total amount to be paid: 52,60€