Php shopping cart script needs to have optional discounts in price.

Ok, I have an existing website that sells cake decorating classes using paypal buttons.

Firstly, I DO NOT want to migrate to a third party shopping cart solution.

All the paypal button information is currently held in a mysql database. I have coded a php shopping cart script that works (although has not yet been added to the site) but I want to have the ability for the admin to turn on and off discounts ("buy 1 get cheapest half price" and "buy 3 for 2"). The discounts need to be linked to a mysql database so that they can be turned on and off from their.

I also need to add a "check out" button that sends all the information from the shopping cart to paypal (with all the necessary variables) for payment.

Stock is controlled on the website by using a paypal IPN listener. This works fine at the moment but may need tweaking with the above work.

I have struggling trying to do all this myself but just don't have the knowledge in php at the moment to do so.

The deadline for this is tuesday evening.

I can send over the website along with the mysql database etc.

Thanks, Mike.