#!/usr/bin/env python3

from subprocess import check_output
from re import findall, DOTALL, MULTILINE

inputs = findall(r'.*?index: (\d+).*?sink: (\d+).*?application\.process\.id = "(\d+)"',
                 check_output(['pacmd', 'list-sink-inputs']).decode("utf-8"), DOTALL|MULTILINE)
sinks = findall(r'index: (\d+)', check_output(['pacmd', 'list-sinks']).decode("utf-8"))
focused_window = check_output(['xdotool', 'getwindowfocus'])
focused_pid = check_output(['xdotool', 'getwindowpid', focused_window]).strip().decode("utf-8")

for app in inputs:
    if app[2] == focused_pid:
        # find new sink index
        index = 0
        for i in range(len(sinks)):
            if sinks[i] == app[1]:
                index = (i + 1) % len(sinks) # rotation
                break
        check_output(['pacmd', 'move-sink-input', app[0], sinks[index] ])
        break