Auto Submit for PPD's on GPT Site.

I am looking for someone that would be able to design a script for the following reason. On my GPT site, I have Pay Per Downloads. The way this works is that the user completes the offer and is given a code, then they must enter the code in and submit it to be verified. This is a timely process and I am looking to automate it. I want a script that will only accept the correct code and approve the offer, there giving the incentive to the user if they have completed the offer correctly. I can give more details when contacted, if there are additional questions.