WoWInterface - Heroic Strike icon border when queued

Hi, this is for the Readyspells addon. The author, Aldmehr, said he would implement this feature if somebody will give him the code.

He has defined the following variable:

Code:

local icon = GetSpellTexture(id, BOOKTYPE_SPELL)

and when the next swing is activated or that spell is on GCD he greys it :

Code:

texture:SetVertexColor(0.4, 0.4, 0.4, self.db.profile.alpha - 0.2)

What i am trying to find out is how to make this icon behave like the regular blizz action bar buttons : white/yellow border on next swing activation buttons like Heroic Strike, Maul, Cleave etc and an "image clock" ungreying it on global cooldown.

Any help will be very much apreciated.