Can anybody please explain this hack?

Suppose you were having a conversation with a demonstrably capable hacker and it doesn't go so well, after which, the following happens:

- You hear what sounds almost like a power generator going off in the distance, except it's a "softer", more "bass"-boosted and buzzing sound and doesn't have that final "crackle" exploding sound at the end; more like a slowed-down version of the sounds leading up to that final "generator blew out during the storm" sound - During this, the light in your room noticeably dims for a brief moment, but then goes back to normal (the nearby cable TV box if fine, not rebooting or anything) - However, your laptop (Mac, if it makes a difference) that you reasonably recently updated the battery for at a reputable, licensed location inexplicably shuts off (no warning, no fan overheating sound (no fan at all, actually), not a lot of apps open to stress processor or memory - Your laptop at this moment was not just fully charged, but also plugged in - The laptop self-reboots, whereupon you notice your battery charge is now inexplicably "0%"; opening up the settings panel, the graph shows that your laptop was in fact fully charged until just a moment ago when the charge inexplicably nose-dived to "0%" (when that outdoor "power generator humming buzzing sound happened and the light dimmed) - This part didn't happen exactly this way and I don't want to go into details of how it did happen, but let's say something like this happened: Upon your laptop rebooting, let's say there is an open sticky note or a notepad app that inexplicably opens also and something like the following was typed in: "Hope you saved your work at (hour)(minute) on (day)(date)" – so basically you do not have doubts that "this was no accident"

My question is 2-fold: (1) How is it possible to instantly discharge your laptop's battery so that it goes from 100% to 0% in a split second, and, more importantly (2) how is it possible to rewrite your laptop's "whatever" so that if the battery suddenly has 0% charge, the hardware is reset to ignore the fact that it can draw power from also being plugged in?

I'm not expecting (though I'd love) any "As a hacker who used to do just this sort of thing to people, I know exactly how they did it" answers, but ANY ideas about how this may have been possible would be greatly appreciated, thank you.