select_audio_sink.py

#!/usr/bin/python3
# vim: ai:sw=4:ts=4:fenc=utf-8

import json
from subprocess import Popen, DEVNULL, PIPE

def list_sinks():
    p = Popen(["pactl", "-f", "json", "list", "sinks"], stdout=PIPE)
    r = p.communicate()
    if p.returncode != 0:
        return None

    data = json.loads(r[0])
    return data

def get_default_sink():
    p = Popen(["pactl", "get-default-sink"], stdout=PIPE)
    r = p.communicate()
    if p.returncode != 0:
        return None

    return r[0].decode().removesuffix("\n")


def show_dialog(data, default = None):
    cmd = ["kdialog", "--geometry", "640x240", "--radiolist", "Select audio sink"]

    for i in range(len(data)):
        #text = "{} ({})".format(data[i]["description"], data[i]["properties"]["alsa.id"])
        text = data[i]["description"]
        selected = "on" if default is not None and default == data[i]["name"] else "off"
        cmd.extend([
            str(i),
            text,
            selected
        ])

    p = Popen(cmd, stdout=PIPE, stderr=DEVNULL)
    r = p.communicate()
    return int(r[0]) if p.returncode == 0 else None


def set_sink(name):
    print("set audio sink: {}".format(name))
    Popen(["pactl", "set-default-sink", name])


def main():
    sinks = list_sinks()
    default = get_default_sink()
    choice = show_dialog(sinks, default)
    if choice is not None:
        set_sink(sinks[choice]["name"])


if __name__ == "__main__":
    main()