The current codebase is not maintainable.
It was primarily inherited from the original version,
making it difficult for other developers to understand.

An effort was made to refactor the old codebase to
improve its maintainability. However, this effort was
overshadowed by the refactoring of the
ClassTestUI-based API, which largely preserved the
old codebase.

To improve the situation, the current codebase needs
to be refactored so that its internals are more accessible
to developers and can be easily extended.