What is needed to integrate VIM motions into an Mac app?

[42mgr]

There is this note-taking app which I love to use on my mac and iphone. It works with txt-files saved to my icloud. You just type markdown. The app only then renders the markdown and provides an interface for the notes. I could directly access the txt file as well and edit it.

I would like to propose the author to add support for VIM motions to his macos app written in swift. I recently was forced to learn VIM motions and pretty amazed, so that I don't want to miss hjkl etc. anymore.

I am a beginner and finished some c/c++/javascript projects (42 core corriculum) and would be grateful for your feedback:

1. what is the complexity of the task to integrate vim motions into a macos app written in swift/swiftui? do you think that it is a good exercise for a beginner?

2. which conditions must be met by the app to be able to add support to it? I would like to suggest the app author to add this feature if he can provide me the API.

3. which existing vim motions logic could be easily/quickly added? (only basic vim features are sufficient) is there a package I could try to integrate?