Available attributes as default

[zaglebie]

Let's say that im selling product XX and i have 2 attributes

1) color black or white
2) model A or B

first attribute is color, black by default

then client can choose model A or B

IF black model B is out of stock then "buy" button dissapears and client is thinking that product is out of stock

BUT model B is available, but not every client will click on droplist

QUESTION IS: how to modify prestashop to show attribute #2 by availability ?

I mean if someone will choose black color and there is no model A then by default there should be showng model B and "buy" button will be active

in this case i wouldnt losing sales because some clients are thinking that NONE of product in black color is available

i know that they can check if other model is available by clicking on droplist but lets be honest, a lot of clients wont do this, first impression counts - OUT OF STOCK ? then im going somewhere else

is there a way to do this ?