Fixing bluetooth stereo headphone/headset problem in ubuntu 16.04, 16.10 and also debian jessie, with bluez5.

a2dp.py

#! /usr/bin/env python3.5
"""
####################################################################
        DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

 Copyright (C) 2016 Vahid Mardani

 Everyone is permitted to copy and distribute verbatim or modified
 copies of this license document, and changing it is allowed as long
 as the name is changed.

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. You just DO WHAT THE FUCK YOU WANT TO.
####################################################################

Fixing bluetooth stereo headphone/headset problem in ubuntu 16.04 and also debian jessie, with bluez5.

Workaround for bug: https://bugs.launchpad.net/ubuntu/+source/indicator-sound/+bug/1577197
Run it with python3.5 or higher after pairing/connecting the bluetooth stereo headphone.

Only works with bluez5.

See `python3.5 a2dp.py -h`.

Shorthands:

    $ alias speakers="a2dp.py 10:08:C1:44:AE:BC"
    $ alias headphones="a2dp.py 00:22:37:3D:DA:50"

    $ speakers


Check here for the latest updates: https://gist.github.com/pylover/d68be364adac5f946887b85e6ed6e7ae

Change Log
----------

- 0.3.0
  * Adding -p / --profile option for using the same script to switch between headset and A2DP audio profiles

- 0.2.5
  * Mentioning [mac] argument.

- 0.2.4
  * Removing duplicated devices in select device list.

- 0.2.3
  * Matching ANSI escape characters. Tested on 16.10 & 16.04

- 0.2.2
  * Some sort of code enhancements.

- 0.2.0
  * Adding `-V/--version`, `-w/--wait` and `-t/--tries` CLI arguments.

- 0.1.1
  * Supporting the `[NEW]` prefix for devices & controllers as advised by @wdullaer
  * Drying the code.

"""

import sys
import re
import asyncio
import subprocess as sb
import argparse


__version__ = '0.2.5'


HEX_DIGIT_PATTERN = '[0-9A-F]'
HEX_BYTE_PATTERN = '%s{2}' % HEX_DIGIT_PATTERN
MAC_ADDRESS_PATTERN = ':'.join((HEX_BYTE_PATTERN, ) * 6)
DEVICE_PATTERN = re.compile('^(?:.*\s)?Device\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
CONTROLLER_PATTERN = re.compile('^(?:.*\s)?Controller\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
WAIT_TIME = .75
TRIES = 4
PROFILE = 'a2dp_sink'


# CLI Arguments
parser = argparse.ArgumentParser(prog=sys.argv[0])
parser.add_argument('-e', '--echo', action='store_true', default=False,
                    help='If given, the subprocess stdout will be also printed on stdout.')
parser.add_argument('-w', '--wait', default=WAIT_TIME, type=float,
                    help='The seconds to wait for subprocess output, default is: %s' % WAIT_TIME)
parser.add_argument('-t', '--tries', default=TRIES, type=int,
                    help='The number of tries if subprocess is failed. default is: %s' % TRIES)
parser.add_argument('-p', '--profile', default=PROFILE,
                    help='The profile to switch to. default is: %s' % PROFILE)
parser.add_argument('-V', '--version', action='store_true', help='Show the version.')
parser.add_argument('mac', nargs='?', default=None)


# Exceptions
class SubprocessError(Exception):
    pass


class RetryExceededError(Exception):
    pass


class BluetoothctlProtocol(asyncio.SubprocessProtocol):
    def __init__(self, exit_future, echo=True):
        self.exit_future = exit_future
        self.transport = None
        self.output = None
        self.echo = echo

    def listen_output(self):
        self.output = ''

    def not_listen_output(self):
        self.output = None

    def pipe_data_received(self, fd, raw):
        d = raw.decode()
        if self.echo:
            print(d, end='')

        if self.output is not None:
            self.output += d

    def process_exited(self):
        self.exit_future.set_result(True)

    def connection_made(self, transport):
        self.transport = transport
        print('Connection MADE')

    async def send_command(self, c):
        stdin_transport = self.transport.get_pipe_transport(0)
        # noinspection PyProtectedMember
        stdin_transport._pipe.write(('%s\n' % c).encode())

    async def search_in_output(self, expression, fail_expression=None):
        if self.output is None:
            return None

        for l in self.output.splitlines():
            if fail_expression and re.search(fail_expression, l, re.IGNORECASE):
                raise SubprocessError('Expression "%s" failed with fail pattern: "%s"' % (l, fail_expression))

            if re.search(expression, l, re.IGNORECASE):
                return True

    async def send_and_wait(self, cmd, wait_expression, fail_expression='fail'):
        try:
            self.listen_output()
            await self.send_command(cmd)
            while not await self.search_in_output(wait_expression.lower(), fail_expression=fail_expression):
                await wait()
        finally:
            self.not_listen_output()

    async def disconnect(self, mac):
        await self.send_and_wait('disconnect %s' % ':'.join(mac), 'Successful disconnected')

    async def connect(self, mac):
        await self.send_and_wait('connect %s' % ':'.join(mac), 'Connection successful')

    async def trust(self, mac):
        await self.send_and_wait('trust %s' % ':'.join(mac), 'trust succeeded')

    async def quit(self):
        await self.send_command('quit')

    async def get_list(self, command, pattern):
        result = set()
        try:
            self.listen_output()
            await self.send_command(command)
            await wait()
            for l in self.output.splitlines():
                m = pattern.match(l)
                if m:
                    result.add(m.groups())
            return list(result)
        finally:
            self.not_listen_output()

    async def list_devices(self):
        return await self.get_list('devices', DEVICE_PATTERN)

    async def list_paired_devices(self):
        return await self.get_list('paired-devices', DEVICE_PATTERN)

    async def list_controllers(self):
        return await self.get_list('list', CONTROLLER_PATTERN)

    async def select_paired_device(self):
        devices = await self.list_paired_devices()
        count = len(devices)

        if count < 1:
            raise SubprocessError('There is no connected device.')
        elif count == 1:
            return devices[0]

        for i, d in enumerate(devices):
            print('%d. %s %s' % (i+1, d[0], d[1]))
        print('Select device[1]:')
        selected = input()
        return devices[0 if not selected.strip() else (int(selected) - 1)]


async def wait():
    return await asyncio.sleep(WAIT_TIME)


async def execute_command(cmd):
    p = await asyncio.create_subprocess_shell(cmd, stdout=sb.PIPE, stderr=sb.PIPE)
    stdout, stderr = await p.communicate()
    stdout, stderr = \
        stdout.decode() if stdout is not None else '', \
        stderr.decode() if stderr is not None else ''
    if p.returncode != 0 or stderr.strip() != '':
        raise SubprocessError('Command: %s failed with status: %s\nstderr: %s' % (cmd, p.returncode, stderr))
    return stdout


async def execute_find(cmd, pattern, tries=0, fail_safe=False):
    tries = tries or TRIES

    message = 'Cannot find `%s` using `%s`.' % (pattern, cmd)
    retry_message = message + ' Retrying %d more times'
    while True:
        stdout = await execute_command(cmd)
        match = re.search(pattern, stdout)

        if match:
            return match.group()
        elif tries > 0:
            await wait()
            print(retry_message % tries)
            tries -= 1
            continue

        if fail_safe:
            return None

        raise RetryExceededError('Retry times exceeded: %s' % message)


async def find_dev_id(mac, **kw):
    return await execute_find('pactl list cards short', 'bluez_card.%s' % '_'.join(mac), **kw)


async def find_sink(mac, **kw):
    return await execute_find('pacmd list-sinks', 'bluez_sink.%s' % '_'.join(mac), **kw)


async def set_profile(device_id, profile):
    return await execute_command('pactl set-card-profile %s %s' % (device_id, profile))


async def set_default_sink(sink):
    return await execute_command('pacmd set-default-sink %s' % sink)


async def main(args):
    global WAIT_TIME, TRIES, PROFILE

    if args.version:
        print(__version__)
        return 0

    mac = args.mac

    # Hacking, Changing the constants!
    WAIT_TIME = args.wait
    TRIES = args.tries
    PROFILE = args.profile

    exit_future = asyncio.Future()
    transport, protocol = await asyncio.get_event_loop().subprocess_exec(
        lambda: BluetoothctlProtocol(exit_future, echo=args.echo), 'bluetoothctl'
    )

    try:

        if mac is None:
            print('Selecting device:')
            mac, _ = await protocol.select_paired_device()

        mac = mac.split(':' if ':' in mac else '_')
        print('Device MAC: %s' % ':'.join(mac))

        device_id = await find_dev_id(mac, fail_safe=True)
        if device_id is None:
            print('It seems device: %s is not connected yet, trying to connect.' % ':'.join(mac))
            await protocol.trust(mac)
            await protocol.connect(mac)
            device_id = await find_dev_id(mac)

        sink = await find_sink(mac, fail_safe=True)
        if sink is None:
            await set_profile(device_id, PROFILE)
            sink = await find_sink(mac)

        print('Device ID: %s' % device_id)
        print('Sink: %s' % sink)

        print('Turning off audio profile.')
        await set_profile(device_id, profile='off')

        if PROFILE is 'a2dp_sink':
            print('Disconnecting the device.')
            await protocol.disconnect(mac)

            print('Connecting again.')
            await protocol.connect(mac)

        print('Setting profile')
        device_id = await find_dev_id(mac)
        print('Device ID: %s' % device_id)

        await set_profile(device_id, PROFILE)
        print('Updating default sink')
        await set_default_sink(sink)

    except (SubprocessError, RetryExceededError) as ex:
        print(str(ex), file=sys.stderr)
        return 1
    finally:
        print('Exiting bluetoothctl')
        await protocol.quit()
        await exit_future

        # Close the stdout pipe
        transport.close()

    if PROFILE is 'a2dp_sink':
        print('Enjoy HiFi stereo music!')
    else:
        print('"Enjoy" your headset audio :)')


if __name__ == '__main__':
    sys.exit(asyncio.get_event_loop().run_until_complete(main(parser.parse_args())))