Can a pothead parent?

My child's father uses marijuana on an almost daily basis. He suffers from anxiety and ADD and says it's the only thing that really helps him relax and sleep. One night he was supposed to watch the baby while I caught up on sleep and when I went into the other room to check on them I smelled weed! I was furious, he just thought it was hilarious, she was only two weeks old! After that I never left her alone with him, he is no longer in the house, and I plan to go to court. Will the court grant him unsupervised visits or even custody with a positive drug test for marijuana? I'm getting different legal advice that say oh any drugs and it's bad on his part vs other legal advice that say judges don't view pot as harshly as long as the parent doesn't do it when the child is present!
I don't want to leave her with him unsupervised, I never thought he was actually an addict (I don't do drugs, but everyone makes it seem like pot is no big deal; almost like smoking a cigarette) but that night he smoked and was supposed to be caring for her, I will never risk that again!