Using functions/parameters to define split in part design

Good day, fellow engineers. I have the following question I would like some assistance with.
Backstory: I have succeeded in using the invert function in GSD, to change the direction of 3 spatial curve offsets- I have linked this invert function to a true/false boolean parameter, using a function, so now I can easily change the direction of the offsets by either setting the boolean to true, which activates the invert, or to false, which deactivates the invert.
Dilemma: I am also trying to link a solid design split function to a similar parameter, to change the side of the performed split. The problem is with a boolean parameter like above, all it does is activate/deactivate the split, so it doesn't help me. I would like (if possible) a parameter that changes the direction of the split. Is there such thing?

I attached 3 pics, the first 2 ones for an easier understanding of how my activated/deactivated invert works, and the third one with the split I am trying to create and control via parameters.

Thanks in advance for any advice you might have.
Best regards,
Bogdan F.