Add an optional status bar to the bottom

[zadjii-msft]

As seen in the original mockups:

We've apparently discussed this in a ton of threads but never had an issue for it. So this is that issue.

Things to consider:

• It must be optional. Many users won't want a status bar.
• How does it play with tabs on the bottom? See Feature request: Enable customization for tabs on bottom/right/left #835
• What info would a user want there?
  • Username, machine name, date/time are all easy kinda Hard, because of SSH.
  • Keep in mind that many things from the shell (child process) we won't be able to access. Things like current path, git branch, active codepage.
    • Working path might be possible with OSC 7 (in Open new terminal tab in same directory as existing tab (OSC 7?) #3158), though, it'll only work for shells that set it (which won't include cmd.exe).
• How does the user specify the contents of the statusbar? Alignment of pieces of info?
• Should the user be able to add buttons to the status bar that perform actions? E.g. a "gear" button to quickly open the settings?

These are all things that should be enumerated in a spec before we review a PR.

[egmontkob]

Things like current path

See OSC 7 in #3158.

git branch

Once you know the current path (and it's a local one), it's easily doable. Maybe watch for the change of whichever file tracks the checked out branch, or update every few seconds, or update every time OSC 7 is reissued.

Just wondering: Would you hardcode getting the git branch, or maybe have a plugin system that can be extended for other VCSs too?

active codepage

Hmmm, does WT not know the codepage (is conversion done by some layer running inside the terminal)?

[zadjii-msft]

See OSC 7 in #3158.

Oh lawd, I forgot that existed. That is excellent, and should definitely be considered for part of this. I'll update the OP. You're right that it does make displaying the git branch much easier (so long as a shell actually sets it 😉)

Hmmm, does WT not know the codepage (is conversion done by some layer running inside the terminal)?

Well no(ish). WT is always running in 65001. Conpty is the layer that's responsible for the magic translation here - it's the one that's actually running in an interesting codepage. It's the one that is changed when the client application calls SetConsole*Codepage. Then conpty does the magic to translate that to UTF-8 for the terminal to consume. So the interesting codepage, the one the client app is running in, isn't really exposed to WT.

[DHowett-MSFT]

Even username/machinename are fraught with peril for anything except local sessions. There's heuristic detection, sure, but that'd require us to crack the title (if we are graced with a shell that sets it) or figure out which part of the output stream is a prompt.

[egmontkob]

Username and hostname can probably be squeezed into OSC 7 without problems, using the standard file://username@hostname/path... syntax. Alas, it needs efforts from OSes (shells etc.) actually emitting it, which doesn't really seem to happen.

[mdtauk]

I'd like to throw my voice in for enabling the status bar to be in the window shell itself, but also to be placed within the terminal area itself, using the profile's colour scheme.

[DHowett-MSFT]

It's just that, like, everything that we can conceivably put in the status bar is already on the screen somewhere, innit?