totally happening
when a person, idea, project, or event goes ahead in a fully present and positive motion to complete/ follow through with itself for the awesomeness of all. A good thing.
This party is totally happening.
that's totally gonna happen
A sarcastic statement used to mock someone's bad idea, pretty much saying it's not gonna work out like that.
Kid 1: "Oh man, my friend and I are gonna go get loaded it in the park!"
Kid 2: "Oh, well, I mean, the police station is right next door... But yeah, no, that's totally gonna happen."
Kid 2: "Oh, well, I mean, the police station is right next door... But yeah, no, that's totally gonna happen."