I would have been fuming and I can't say what I would have done but I'm pretty sure I wouldn't have hit him back. I would have called the police. I guess you're lucky he didn't because you both could have ended up in jail. At least, you could here. It sounds to me like he's stalking you. And with people like that, little pieces of paper(restraining order or such) I'm afraid don't do much good. Is there any way you can get transferred away from him? And I think you've been documenting all this, right? Now is the time to show it to your supervisors. I wouldn't have let it go this far.