Redeeming reward points

Hello everyone,
I have been using opencart for my new business for a couple of months, and it's awesome that we can get this for free!
I'm toying with the idea of using reward points, but it seems that the way points are redeemed isn't quite what I had hoped for.
I want customers to earn points on purchases, but only to be able to redeem the points when they have enough points to buy 100% of a product - much like my well used Nando's card
So I don't want the customer to use points to receive a partial % discount on the total.
Is this possible with the standard opencart system, or will I need some kind of add-on extension?
Thanks in advance for any help or info.

there's an extension out there to do the job

May I know WHICH extension can accomplish this?

Perhaps a search on the market will get you what you need: http://www.opencart.com/index.php?route ... d%20points

I cant find an extension that can actually do what I need,

so I tried solving this myself, this is what I am able to achieve so far:

-redeem nth (1, 3, 2 etc) number of same products with nth amount points ( points need EXACTLY nth amount, no less, no more, disabled using points as partial discount)

-this only works when there is 1x point redeemable product in the cart, if more it wont work
-redeem all/or x number of same product and pay the rest with credit.

What I am unable to solve:

- If I have 2x T products ( redeemable ) + 6x Y point products ( redeemable ) in Cart

and I want to:

pay only 1x T products with points + 3x Y product with points ( paid in total EXACT point amount, no more/less, cannot use points as partial discount)

is that possible? or impossible?