Requested WoW macro

I’ve been checking quite a bit of macro’s and found one that checked the players health and had 2 different actions depending on how hight the HP of the player was.

Now I was thinking if it’s possible to do the same but with resource so:

f.e. players focus >/= 20 use arcane shot
// < 20 use cobra shot

I know I can pretty much do a likewise system through cast-sequences but with the crap load of different ways hunters recover focus this would be much more useful.