Adding a custom variable on product page

[yesdev]

I have a new challenge to try & deliver for our store.

 

I need a way to add a product to the cart when:

• it's not associated with the current product on the product page
• you are selecting the colour "product"

I'm trying to do an algorithm to match product colours of our main products to "sample" products we sell cheaper. I don't want to do manual association as it's too much work.

 

Any ideas?