Tracking rotation

Making a datapack with origins, basically want to be able to track how far I've rotated the camera horizontally by saving the current rotation with one command,then saving another rotation briefly after, and then doing math to find the difference.
I want to be able to get the difference of both turning left and turning right, as seperate functions.
BUT
rotation in minecraft is weird and stupid, and goes from like 0 - >179 - > - 180 then back to 0 (something along those lines),which makes it really annoying to do the math when dealing with negatives.
Not sure if I've missed something obvious but yea