I've been learning C++ from a book lately and I've been making something of a console game/thingy, and a map editor for it... Whatever it is I'm just coding and it's being fun and interesting, but I've coded it all in one file, both because I wasn't expecting to get so far with it, and because I don't know any better. At some point I moved all the declarations into a header file to make it easier to tweak things without as much hassle, but it's still being a huge hassle, it's becoming too much to cope with. I'm well over 2000 lines of code (on the map editor alone, including comments and garbage), and I'm finding it too confusing. An example of a side effect I found was that I was assigning values to the same variable from three different functions during the initialization. But I'm finding it hard to detect and fix stuff like this in all of this mess.
So I need to separate my code into more files, but I haven't learned anything about classes or even header files yet. I "know" what they are and what they're for, but I can't make them on my own yet. So what I need is a quick (and maybe dirty) way to just break up the code and make it bearable, because if I stop working on it I'll eventually lose motivation to keep learning. It doesn't matter if it's a cheap thing to do, the project isn't important, it's just a way to get my hands dirty and learn from mistakes. Like my father said once, analogously, your first car is for you to break.
So if anyone could give me some hints or thoughts on how to go about separating the code into more .cpp or .h files I'd really appreciate it. My biggest problem is with avoiding calling the same header file from several files, I think. But I also feel confused on things like, should I just create header files, should I just create cpp files, should I create both as needed, and how do I determine if they're needed, and how exactly do I make the code from one file interact with the code from the other...
Any help is greatly appreciated. Thanks.