Style-dependent variables?

I'm building a fairly complex document -- mostly in Writer, with one Calc and a number of Writer subdocuments, and using Base (for now) to manage tables that supply lists in the master document. There are a lot of alternative sections and conditional text, most controlled by a number of variables I defined and maintain in hidden fields in the master document. It works decently, but I see that some aspects could be simplified with system variables (if they exist) rather than user-defined variables.

Here is an example: Can text on a page be made dependent on the style (that is, presumably, the style name) of that page? If it is not a built in system variable, how might I query a style name (or even a style definition)?

A second problem at this stage of development is how to give someone else easy access to control/modify the variables in those hidden fields. I've looked at appropriate form controls but don't see how to link a control to a variable in the document. Can someone point me in the right direction for that?

Thanks,
John