wpslide

#!/usr/bin/env python3

from os import listdir
import os.path
from random import shuffle
import urllib.parse
import subprocess
import sys
from time import sleep
from argparse import ArgumentParser
from shlex import quote


DESKTOP = '''[Desktop Entry]
Type=Application
Name=Wallpaper Slideshow
Exec=%s'''


class WPSlide(ArgumentParser):
    def __init__(self):
        ArgumentParser.__init__(self, prog='wpslide', description='Wallpaper Slideshow')
        self.add_argument('-d', '--directory', action='store', type=str, dest='picdir', default=os.path.expanduser('~/Pictures'), metavar='DIR', help='path to directory containing picture files (%(default)s)')
        self.add_argument('-t', '--time', action='store', type=int, dest='delay', default=10, metavar='TIME', help='time in minutes between pictures (%(default)smn)')
        self.add_argument('--gsettings', action='store', type=str, dest='gsettings', default='/usr/bin/gsettings', metavar='PATH', help='path to the gsettings executable (%(default)s)')
        self.add_argument('--notify', action='store', type=str, dest='notify', default='/usr/bin/notify-send', metavar='PATH', help='path to the notify executable (%(default)s)')
        self.add_argument('--schema', action='store', type=str, dest='gschema', default='org.gnome.desktop.background', metavar='SCHEMA', help='Gnome property schema for background (%(default)s)')
        self.add_argument('--keys', action='store', type=str, dest='gkeys', default='picture-uri,picture-uri-dark', metavar='KEYS', help='Gnome property keys for background (%(default)s)')
        self.add_argument('-o', '--output', action='store', type=str, dest='output', default=os.path.expanduser('~/.config/autostart/wpslide.desktop'), metavar='PATH', help='file where to write desktop (%(default)s)')
        self.add_argument('--history', action='store', type=str, dest='history', default=os.path.expanduser('~/.config/wpslide/history'), metavar='PATH', help='file containing wallpaper history')
        self.add_argument('action', action='store', type=str, choices=('start', 'desktop'), metavar='ACTION', help='start: start slideshow, desktop: write desktop file')

    def run(self):
        self.args = self.parse_args()
        if self.args.action == 'start':
            self.start()
        elif self.args.action == 'desktop':
            self.write_desktop()
        else:
            raise RuntimeError('action: %s?' % self.args.action)

    def start(self):
        history = self.read_history()
        piclist = listdir(self.args.picdir)
        gkeys = tuple(k.strip() for k in self.args.gkeys.split(','))
        while True:
            shuffle(piclist)
            for pic in piclist:
                if pic in history:
                    sys.stderr.write('Skip %s\n' % pic)
                    continue
                abspic = os.path.normpath(os.path.join(self.args.picdir, pic))
                picuri = 'file://' + urllib.parse.quote(abspic)
                for key in gkeys:
                    cmdline = [self.args.gsettings, 'set', self.args.gschema, key, picuri]
                    subprocess.run(cmdline)
                cmdline = [self.args.notify, 'Set wallpaper', '-i', abspic, pic]
                subprocess.run(cmdline)
                self.add_to_history(pic)
                sleep(self.args.delay * 60)
            history = set()
            self.clear_history()

    def read_history(self):
        if os.path.isfile(self.args.history):
            with open(self.args.history) as f:
                return set(line.strip() for line in f)
        else:
            return set()

    def add_to_history(self, pic):
        with WPSlide._open(self.args.history, mode='a') as f:
            f.write(pic)
            f.write('\n')

    def clear_history(self):
        with WPSlide._open(self.args.history):
            pass

    @staticmethod
    def _mapargs():
        first = True
        picdir = False
        for arg in sys.argv:
            if first:
                yield os.path.abspath(arg)
                first = False
                continue
            if picdir:
                yield os.path.abspath(arg)
                picdir = False
                continue
            if arg == '-d' or arg == '--directory':
                yield arg
                picdir = True
                continue
            if arg == 'desktop':
                yield 'start'
                continue
            yield arg

    @staticmethod
    def _open(path, mode='w'):
        dirname = os.path.dirname(path)
        os.makedirs(dirname, exist_ok=True)
        return open(path, mode)

    def write_desktop(self):
        cmdline = [quote(arg) for arg in WPSlide._mapargs()]
        with WPSlide._open(self.args.output) as f:
            f.write(DESKTOP % ' '.join(cmdline))


if __name__ == '__main__':
    WPSlide().run()