{ pkgs, config, ...}:
{

  kassouni.palette.commands = [
    {
      name = "bluetooth";
      icon = "󰂯";
      # `jc --bluetoothctl` turns `bluetoothctl devices` into JSON, so the menu is
      # built from parsed records rather than by splitting "Device <addr> <name>"
      # lines. That subcommand leaves every status field empty, so connectedness
      # comes from a second `devices Connected` call intersected on address.
      exe = pkgs.writers.writePython3 "bluetooth-toggle" {
        # The interpolated store paths below are longer than 79 columns.
        flakeIgnore = [ "E501" ];
      } ''
        import html
        import json
        import subprocess
        import sys

        BT = "${pkgs.bluez}/bin/bluetoothctl"
        JC = "${pkgs.jc}/bin/jc"
        ROFI = "${pkgs.rofi}/bin/rofi"


        def devices(*args):
            """Parse `bluetoothctl devices [args]` into a list of records."""
            listed = subprocess.run(
                [BT, "devices", *args], capture_output=True, text=True
            )
            parsed = subprocess.run(
                [JC, "--bluetoothctl"],
                input=listed.stdout,
                capture_output=True,
                text=True,
            )
            return json.loads(parsed.stdout or "[]")


        def label(device, connected):
            """Pango markup row. Names are escaped, they are not our text."""
            name = html.escape(device["name"])
            if device["address"] in connected:
                name += ' <span alpha="45%">connected</span>'
            return name


        def main():
            known = devices()
            if not known:
                return 0

            # Older bluez has no `devices Connected`; that call just comes back
            # empty there, which degrades to "nothing is connected".
            connected = {d["address"] for d in devices("Connected")}

            rows = [label(d, connected) for d in known]
            choice = subprocess.run(
                [ROFI, "-dmenu", "-i", "-markup-rows", "-format", "i",
                 "-p", "bluetooth"],
                input="\n".join(rows),
                capture_output=True,
                text=True,
            )
            if choice.returncode != 0:
                return 1

            device = known[int(choice.stdout.strip())]
            action = (
                "disconnect" if device["address"] in connected else "connect"
            )
            return subprocess.run([BT, action, device["address"]]).returncode


        if __name__ == "__main__":
            sys.exit(main())
      '';
    }
  ];
}