custom shopping cart

We need affiliate promo codes discounts tracked with use of open source shopping cart. ? osCommcerce or xen cart preferred.? **Cart Requirements:** - Generate eGift eCertificates - Track? promo codes issued to our affiliates - Apply two separate discounts to each promo code, discount A, discount B. - Discount A gives % discount to customer at time of purchase. - Discount B will be tracked against promo code being used and then issued back to affiliate using promo code - Web interface for affiliates to track use of promo codes - MysQL database needed to store data - [login to view URL] and or Pay Pal will be the gateway. Our site only offers 1 service at 69.99$ Customers can buy and use this service at time of purchase.? Successful transaction will propegate a hosted URL which will populate two fields,? this is the service the customer seeks.? Customers can purchase this service as a gift card. Promo Codes will be given out to affiliates. Affiliates will then use the Code. Affiliate Code will give customer %A discount at time of purchase. Affiliate Code will also generate %B discount to be tracked and given back at a later time. Web front end so affiliates can track use of Promo Codes. **Hosting info** -linux -PHP 5.x