Looking for Best Buy More Save More Solution with POS and adjusted return value

Hi All,

We operate and E-com and Retail Store business. We are looking for a Buy More, Save More Solution that can work on both online and in store.

Example:

Spend $250 get $50 off your purchase

Spend $500 get $125 off

Spend $1000 get $300 off

Also need it to adjust value of discount upon a return taking place.

Example:

Customer spent $1000 received $300 off. Returns $300, now total transaction has a discount value of only $125.

Does this exist?