mod so customer can only see category related specifically to them

Hello forum!

I have been searching for days for a solution for my requirement, but have been unsuccessful.

I am a photographer. I take photos for weddings, etc. These photos should not be available for "everyone" to see and purchase. I want to modify zen cart so that a particular customer can only see and purchase a particular set of photos.

Here's how I see this working:

1. I make a category for the customer's photos.
2. I "tag" the category with a unique code (an attribute of the category).
3. I photograph an event for the customer.
4. I give the customer the category's unique code.
5. I create the products, inside the category, which are available for purchase (packages of photos that I will print for the customer - no photos will be available for download).
6. The customer creates a new login (new registration) on the site.
7. The form for a new login (registration) contains a required field for the customer to enter the category's unique code.
8. When the customer clicks "submit", the unique code is validated.
9. On a successful login creation (registration) the customer can see only the category which matches the unique code the customer entered during login creation (registration).
10. The customer shoud be allowed to add more unique codes if they have more than one set of photos (products). (e.g. wedding photos in June = one category/unique code, and family portraits at Christmas time = another category/unique code)

I have installed the hideCategories mod, but this alone does not fulfill my requirement.

Someone please point me to a mod/addon, or get me started with creating the mod myself, please :)

Please note: I have limited PHP programming experience.