How do i keep track of individual products

Hey all,

opencart version 1.4.9.3

I am currently developing a gift registry module and i have run into a bit of a problem.

I need to be able to track the products that were selected from a gift registry until checkout so that i can remove them from gift registry once it has been bought.

What happens currently is a user comes to the site and selects all of the products that they want in there gift registry and creates the gift registry with the items in it.
Then their friends come along a view the registry. If one of the users friends want to buy something they select one of the items and it goes into their cart. They then checkout the item as normal.

My problem is that. How can i track the item once it has been selected, so that i can update the gift registry to reflect the now fewer products? This will stop people from buying two of the same item.

I appreciate any advice you are willing to give.

Nooblet

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