Show add to cart button if the goods have 1 attribute

[habross]

Hello,


I have a delicate problem. The administration can enable or disable the add to cart button, if the goods have or haven´t attributes. I am using layered filter because I want to have a unified color catalog with colors in the form of attributes, It means that black chair that has no other color attributes, I set the attribute to black and now the search is located among others. But there does not appear click add to cart.


Therefore, the question is: Does anyone know where in the code to set this condition to click Add to Cart if the goods have one attribute? If 2 or more obviously make this button disappearing.


Thanks for any ideas