add keybindings: prev_output, prev_output_with_win

[A7R7]

provide an api wf::output_t *get_prev_output(wf::output_t *output) in core/output-layout.hpp
and use this api to implement prev_output and prev_output_with_win
fixes #2071

[A7R7]

Haven't noticed there's already #1570. I may take up his work then

[ammen99]

As mentioned in the other PR (#1570) there are two changes needed:

• The get_prev_output() shouldn't be added to core at all, oswitch can do that on its own.
• It would be nice to refactor the code so that the functions for next and previous output reuse the same code. Currently, they do the exact same thing but with the only difference of previous/next output. I imagine it should be easy to refactor them to use a common function switch_to_output(target_output) and switch_to_output_with_window(target_output)

[A7R7]

I did some refactor to the original functions, most importantly add get_output_relative to get the target monitor instead of changing the core api. The 4 activator_callbacks now only use switch_to_output(target_output) and switch_to_output_with_window(target_output) to finish their jobs.

I haven't implement swap_output and swap_output_prev in #1570, because I'm not sure if it is better to swap only the top view or swap the whole active workspace on the 2 outputs, or if it is good to add both functionalities (which I think will be a little mess).

[ammen99]

I haven't implement swap_output and swap_output_prev in #1570, because I'm not sure if it is better to swap only the top view or swap the whole active workspace on the 2 outputs, or if it is good to add both functionalities (which I think will be a little mess).

That is fine, since you are doing the work, you can only add whatever you find useful :)

[ammen99]

LGTM now, thanks!

[ammen99]

Please fix code style as well (there is a diff in the CI logs)

[A7R7]

I've fixed the code style with your fork of uncrustify, hopefully it can pass!