HELP! Your opinions will be greatly appreciated!

It is saturday morning, barely hitting noon time and the rain is killing me! but yes i am blogging on a saturday morning. last night was one of the most humiliating night i've had yet! like every other college student would do on a friday night, i was stuck at a karaoke bar with a group of my friends. and what takes place at bars when all these testosterone filled males are intoxicated? immature fights of course, it just so happened that i was there and witnessed the fight from beginning to end. The tension began when i was playing a game of dice called "bullshit" with a fellow friend of mine...more of an acquaintance i would say. when a good friend of mine came over to give me some tips on how to beat this guy. this acquaintance who was obviously mad because he was losing to a girl decides to take a dice cup and chucks it at my friends face. It all happened so fast, i didnt know how to react. i can feel the fire coming up from the throat and out my nose and eyes! my friend's eyes end up cut and he was blind for literally a few minutes due to the force and close distance of the throw. Can you guys feel the anger inside me? How can someone hurt somebody else merely over a game? a room full of friends enjoying a fun night is now ruined, and is full of worry, anger and many more.
Thank god my friend is okay because we brought him to the ER and the doctor said as long as the swelling goes down, his eyes will be okay again. My friend also files a police report at the ER for assault. now this is where i need help. my friend called me about 30 minutes ago, asking if he should keep the case open. I mean they "were friends" even though they've had a few grudges prior to this incident. My friend just want the guy to pay his medical bills and maybe call it even. What do you guys think? The guy obviously was immature, and was not feeling sorry for what he did. so should be be put behind bars? or should he just be liable for the medical bills? which way will let him learn a lesson and learn from his mistakes? pleasee help!