Easy OpenCart module needed

Looking for someone to create a simple open cart module. Right now on my website I have an exit intent popup (and a static page) that offers a user one free item if they share our website on facebook. Right now everything is done manually. They share the website then send me and email and I create them a gift voucher to use to get their free item. I want this to be automated in this way: 1) The user will be asked to share on facebook. It will bring up the Facebook share dialogue box. 2) After they share the page it will say "Thank you for Sharing" Please sign up for an account to receive your free item. 3) After they create an account. It should say "Congratulations! Continue shopping and 1 items in your shopping cart will be free". (A link will be presented to continue shopping.) 4) At checkout the cheapest item in the cart should be discounted and given free. This should be made as a separate module and should use OCmod or VQmod so it does not interfere with any of the core files.