Script to move Plasma panel to the primary screen

fix-plasma-panel.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Copyright © 2019 Martin Ueding <dev@martin-ueding.de>

# Licensed under the MIT/Expat license.

# Based on https://bugs.kde.org/show_bug.cgi?id=356225#c312

import argparse
import configparser
import difflib
import os
import subprocess


def get_current_primary():
    output = subprocess.check_output('xrandr').decode()
    lines = output.split('\n')
    for line in lines:
        if 'connected primary' in line:
            words = line.split()
            return words[0]

    raise RuntimeError('No primary screen could be found')


def get_plasmashell_screen_id(identifier):
    config = configparser.ConfigParser(strict=False)
    config.read(os.path.expanduser('~/.config/plasmashellrc'))
    for key, value in config['ScreenConnectors'].items():
        if value == identifier:
            return key

    raise RuntimeError('Screen could not be found in plasmashellrc')


def set_appletsrc_screen(primary_id, dry):
    path = os.path.expanduser('~/.config/plasma-org.kde.plasma.desktop-appletsrc')

    with open(path) as f:
        content = f.read()

    paragraphs = content.split('\n\n')

    for i, paragraph in enumerate(paragraphs):
        lines = paragraph.split('\n')
        if any(line == 'plugin=org.kde.panel' for line in lines):
            others = [line for line in lines if not line.startswith('lastScreen=')]
            others.append('lastScreen=' + primary_id)
            paragraphs[i] = '\n'.join(others)

    new_content = '\n\n'.join(paragraphs)

    diff = list(difflib.unified_diff(content.split('\n'), new_content.split('\n')))
    if len(diff) > 0:
        print('Will make the following changes:')

        for d in diff:
            print(d)

        if not dry:
            with open(path, 'w') as f:
                f.write(new_content)

    else:
        print('No changes necessary')


def main():
    options = _parse_args()

    primary_name = get_current_primary()
    print('Found primary screen: {}'.format(primary_name))

    primary_id = get_plasmashell_screen_id(primary_name)
    print('Found matching ID: {}'.format(primary_id))

    set_appletsrc_screen(primary_id, options.dry)


def _parse_args():
    '''
    Parses the command line arguments.

    :return: Namespace with arguments.
    :rtype: Namespace
    '''
    parser = argparse.ArgumentParser(description='Changes the `lastScreen` attributes of the plasmashell containments such that the panel is on the primary screen.')
    parser.add_argument('--dry', '-n', action='store_true', help='Change nothing, only display proposed changes')
    options = parser.parse_args()

    return options


if __name__ == '__main__':
    main()