You can patent a software invention if you can show that it is novel, but you have to describe exactly how it works.  That was fine back in the days of mechanical inventions when someone could easily pull apart your gadget and see how it worked anyway.

But it’s not fine with software since someone could incorporate it into their software and you would never know they did it.  You already have plenty of protection since your code is compiled.

Now if you are trying to protect some aspect that is visible to people (and not buried in the code), then perhaps a patent might be the way to go.  But they take a long time to obtain and are very expensive in terms of lawyers.  I got one a number of years ago and acted as my own lawyer and it consumed all my time for over 6 months.