So then the decision to shoot you or not shoot you is entirely up to my analysis of the situation? No other guidelines other than what I perceive your intent to be?
Correct. The legal standard is, and always has been: 'Did you act out of a reasonable fear of serious bodily harm?"
A grand jury may be asked to opine on the reasonableness of your fear, but that's the standard.
This is why it is a bad idea to randomly tackle armed strangers in the middle of the night - they might not always realize that you were just playing a hilarious joke.