Extending C++ language

Hello, I am interested in making a CLion plugin that implements support for the CUDA framework and syntax. Since CUDA is often mixed in with C++ in a single file, I want to extend the language for only *.cu and *.cuh files, without having to reimplement a C++ plugin. Is this possible? If so, what classes would I look at for extending the lang? I saw a similar question from 4 years ago, so I am not sure what all has changed.