script to switch gnome, gedit and atom theme between light and dark. made for better day/night readability.

gnome-switch-night-mode.py

#!/usr/bin/env python3

from sys import argv, exit
from os import popen
from os.path import join, expanduser as get_path
from re import search

if '-h' in argv or '--help' in argv:
  print('''
  Executing this program will invert dark/light colors
  of OS between yaru-light and dark;
  gedit between kate and cobalt
  and atom between one-light and dark.

  -d to set dark theme
  -l to set light theme
  ''')
  exit()

def command (cmd):
  return popen(cmd).read()

home_path = get_path('~')
gnome_command = 'gsettings {} org.gnome.desktop.interface gtk-theme '

# identify color mode
is_dark = 'dark' in command(
  gnome_command.format('get')
)
print('OS theme is dark: ' + str(is_dark))

if '-d' in argv or '-l' in argv:
  is_dark = '-l' in argv
  print('Force {} theme'.format('light' if is_dark else 'dark'))

def change_atom_file (is_dark):
  path = join(home_path, '.atom/config.cson')
  f = open(path, 'r').read()

  ui_re = search('\"[a-z\-]+\-ui\"', f)
  syntax_re = search('\"[a-z\-]+\-syntax\"', f)
  ui = f[ui_re.start() + 1:ui_re.end() - 1]
  syntax = f[syntax_re.start() + 1:syntax_re.end() - 1]

  new_ui = ui
  new_syntax = syntax

  if is_dark:
    if 'light' not in ui: new_ui = ui.replace('dark', 'light')
    if 'light' not in syntax: new_syntax = syntax.replace('dark', 'light')
  else:
    if 'dark' not in ui: new_ui = ui.replace('light', 'dark')
    if 'dark' not in syntax: new_syntax = syntax.replace('light', 'dark')

  f = f.replace(ui, new_ui)
  file = f.replace(syntax, new_syntax)

  f = open(path, 'w')
  f.write(file)
  f.close()

# set mode colors
cmd_set_os = gnome_command.format('set')
gedit_command = 'gsettings set org.gnome.gedit.preferences.editor scheme '
if is_dark:
  command(cmd_set_os + 'Yaru-light')
  command(gedit_command + 'kate')

else:
  command(cmd_set_os + 'Yaru-dark')
  command(gedit_command + 'cobalt')

change_atom_file(is_dark)