cornetroll 🥐

For those of you ricing up your custom tiling window manager desktop, I bring you cornetroll: the professional ricer's MPRIS controller! See, cornetroll is an anagram for controller and a cornet (cornetto) happens to be the name of a pastry, which is a kind of croissant, and those are quite twisty, almost like they're rolling. The layers!

Features

• Flexible formatting: You can customize what and how the controller shows information.
• Supports multiple players: It keeps track of the available players and you can iterate through them.
• Inline controls: It can also emit polybar or EWW actions that send commands to the current player.
• Scrollable metadata: No, really - scrollable metadata. You know those huge-ass song titles that pollute your bar, tripping all over your other modules? Those problems are over, pal!

Building

Make sure you have Rust 1.74.0+ and Cargo installed. You can build and install a release build at ~/.cargo/bin by running:

cargo install --path .

Usage

If called without arguments, cornetroll will start its main interface in "tail mode", meaning that unless terminated it will always constantly print lines of text with the current state every tick (300ms).

Every tick one character is scrolled in the [metadata] and [info] blocks (see Display Format below) if their content are bigger than the allocated maximum character length. The scrolling is bidirectional, changing directions when reaching the start or end of the truncated content.

Usage: cornetroll [OPTIONS] [command]

Arguments:
  [command]  Which command to send to the current running instance [possible values: play, pause, stop, prev, next, prev-player, next-player, play-pause]

Options:
  -f, --display-format <display-format>
          How the player presents itself [default: "[prev] [play-pause] [next] [info] ┃ [metadata]"]
  -m, --metadata-format <metadata-format>
          What information about the song will be shown [default: "<[artist] - >[title]"]
  -r, --refresh-ticks <refresh-ticks>
          How many ticks to wait to refresh the player cache. [default: 10]
  -t, --markup-type <markup-type>
          What kind of markup should cornetroll output, if any. [default: polybar] [possible values: polybar, yuck, none]
  -e, --empty-msg <empty-msg>
          The text to show when no players are available [default: "\u{f057} no music playing"]
  -h, --help
          Print help
  -V, --version
          Print version

When running a release build, cornetroll creates a named pipe at /tmp/cornetroll.$USER and listens to it for any commands sent by cornetroll [command] (or written directly to the socket). As sockets go, you can't have more than one instance of cornetroll using it at the same time, so you'll get an error if the socket exists when trying to run cornetroll.

When running a debug build on the other hand, cornetroll turns into an interactive minimal TUI that allows you to control the player directly without using a socket for development purposes.

Display Format

The formatting of what will be outputed by cornetroll every tick, defined by bracket-surrounded identifiers called blocks (e.g. [foo]). Blocks may have comma-separated arguments after a colon (e.g. [foo:arg1,arg2]). All arguments are optional, and you can skip the first one by leaving it empty (e.g. [foo:,arg2]).

Action blocks

These blocks generate inline actions (when --markup-type is not none, see Markup Types below) that allow you to interact with cornetroll by issuing commands to itself.

• [prev]: Previous track button. This previous command to the current instance.
• [play-pause]: A dynamic play/pause button, changing according to the current playback status. Likewise, sending a play-pause command.
• [next]: Next track button. next command.

Text blocks

• [status]: An action-less play-pause, just showing the current playback status. Note that the icons shown are the opposite of play-pause's, plus the stop icon.
• [info:show_total,show_name]: Shows the current focused player in the following format: current/total: name. The two arguments control whether total and/or name will be shown, being either true or false. Both are true by default. name is on a 10-char scroll buffer, with the same wait ticks as metadata's default.
• [metadata:buffer_size,wait_ticks]: This block is mandatory, if it's not present cornetroll will throw an error. A scroll buffer showing the current player's song information. buffer_size is how many characters the scroll buffer will take (32 by default), and the metadata section will always be that many chars wide. When the metadata string is longer than buffer, the scroller waits wait_ticks ticks before it starts scrolling, and after every bounce.
• [time:show_length,use_remaining]: Show the current track's position in MM:SS format. Both arguments are bool. show_length will show the track's length alongside the position, as in 01:23/04:32. If use_remaining is true, the length will show how much of the track is left instead. If show_length is false and use_remaining is true, only the remaining time will be shown.

Icons used by blocks

Assuming you have FontAwesome's Regular and Solid styles installed and configured in your bar:

• prev:  (\uf04a).
• next:  (\uf04e).
• play-pause: ,  (play \uf144, pause \uf28b).
• status : , ,  (play \uf144, pause \uf28b, stop \uf28d).

Markup Types

cornetroll can output its interface in three modes, chosen by the --markup-type command line option: polybar, yuck and plain. This mostly affects how actionable blocks generate inline clickable actions.

polybar

If you're using polybar, cornetroll will emit polybar action markup for the action blocks, but will output the text blocks as they are. That means you can also use other kinds of polybar markup when setting the display format string.

yuck

cornetroll will emit an EWW widget (box) with a cornetroll class, with each action block being a button and text blocks being labels with Pango markup enabled. Like with the polybar markup type, you can also define your own widgets in the display format string.

none

Every display block will be output as plain text, without any markup of any kind. You can still write custom markup in the display format string when using polybar or EWW.

Metadata Format

What will be shown inside the metadata block, using the same bracket syntax as the display format string.

• [artist]: The first/main artist
• [artists]: A list of artists separated by a comma.
• [album]: The song's album
• [album-artist]: The album's artist
• [title]: The song's title
• [track]: Track number

If the correspoding tag is not set, cornetroll will show it as N/A.

Optional sections

You can make part of the metadata optional (e.g. only show artist name when the tag is actually set) by enclosing it in brackets <...> (e.g. <[artist] - >[title]). Essentially what this does is control the output of strings before and after a valid block. Some examples:

• <[artist] ->[title] - If artist is set, the result is Artist - Title, otherwise it's Title.
• <[artist] - [title]> - If only artist is set, the result is Artist. If only title is set, the result is - Title. If both, Artist - Title.

Optionals can also be nested, allowing you to make somewhat complex metadata formats.