404117 Coupon Code

I have a customer that wishes to add a coupon code to thier existing ecommerce site. This is a custom ecommerce site not a open-source example. In admin, you will have a section (link) that reads "add coupon". When selected you see a drop down that reads - - percent - amount The second drop down reads - - time can be used - 1 to 100, 200, 250, 300, 350, 400, unlimited Field for Coupon Code to be entered - field (Alpha-numeric) Currently thier is an option in admin for free shipping - this is not to get affected in anyway at all. The next link will read - "edit coupon" This page will be nothing but a table of 3 columns by 1 row, etc of hyperlinks of coupons codes used. When clicked on, you see the like above in "Add Coupon" but already filled out where you can make changes. The next change is under the Orders link. When an order is made, the Order table is updated. I need an additional field here marked "coupon" so that it can appear in the order summary for a specific order. When an order number is selected from the order tabe, I need to be able to see what customer used that coupon code. On the front end of the site, [login to view URL], this is where you will put the code field at. The customer already puts in thier zip code for shipping, just place a new field next to it called 'coupon code'. They can type in one if they have it or leave it blank if they don't. The coupon code will have its own submit button as the first one processes the zip code. Once the order is complete, you will need to modife the 2 emails sent to both customer and admin to show a coupon code used. That's it - please ask questions if need be.