Literally means the exact opposite, the furthest thing from nice. Used as a conversation stopper when you when you are too scared to call a friend out on their shit but just pray they don't give you any more details. Bonus points if you send it over text, extra bonus points if it is over two separate texts.

when you're hungover as shit after a spending a night drunk as a skunk

A positive message. Used as a compliment if someone does something good or funny.