Downloads and show random xkcd comic as i3lock background

i3lock-xkcd.py

#!/usr/bin/env python3

# i3lock-xkcd.py
# Downloads and show random xkcd comic as i3lock background

import os
import sys
from subprocess import run
from tempfile import NamedTemporaryFile
from textwrap import wrap

from xkcd import getRandomComic
from PIL import Image, ImageDraw, ImageFont
from screeninfo import get_monitors

# Set options below
FONT_FAMILY = "xkcd.otf"
FONT_TITLE_SIZE = 36
FONT_ALTTEXT_SIZE = 12
RESIZE_RATIO = 0.8


class I3LockXkcdException(Exception):
    pass


class I3LockXkcd(object):
    def __init__(self, filename, resolution, retries=3):
        for i in range(retries):
            try:
                self.xkcd = getRandomComic()
                self.xkcd.download(
                    os.path.dirname(filename),
                    os.path.basename(filename)
                )
            except:
                # Maybe we got a comic that can't be downloaded
                # (like 1190: Time), so we try again
                next

            self.bg = Image.new("RGBA", resolution, "white")
            self.bg_w, self.bg_h = self.bg.size

            self.comic = Image.open(filename)
            self.comic_w, self.comic_h = self.comic.size

        if not self.comic:
            raise I3LockXkcdException("No comic has been downloaded")


    def get_image(self):
        self.draw_comic()
        self.draw_title()
        self.draw_alttext()

        return self.bg

    def draw_comic(self):
        # Calculate comic offset relative to background
        offset_w = (self.bg_w - self.comic_w) // 2
        offset_h = (self.bg_h - self.comic_h) // 2
        offset = (offset_w, offset_h)

        # Draw comic inside background
        self.bg.paste(self.comic, offset)

    def draw_title(self, base_offset=100):
        # Draw title above comic
        font = ImageFont.truetype(FONT_FAMILY, FONT_TITLE_SIZE)
        title = ImageDraw.Draw(self.bg)
        xkcd_title = self.xkcd.getTitle()
        title_w, title_h = title.textsize(xkcd_title, font=font)

        # Calculate title offset relative to comic
        offset_w = (self.bg_w - title_w) // 2
        offset_h = (self.bg_h - self.comic_h - base_offset - title_h) // 2
        offset = (offset_w, offset_h)

        # Draw title inside background
        title.text(offset, xkcd_title, font=font, fill="black")

    def draw_alttext(self, line_offset=100):
        # Draw alt-text above comic
        font = ImageFont.truetype(FONT_FAMILY, FONT_ALTTEXT_SIZE)
        alt_text = ImageDraw.Draw(self.bg)

        # Since alt-text can be too long, we wrap it using textwrap.wrap
        for line in wrap(self.xkcd.getAltText(), width=120):
            line_w, line_h = alt_text.textsize(line, font=font)
            offset_w = (self.bg_w - line_w) // 2
            offset_h = (self.bg_h + self.comic_h + line_offset - line_h) // 2
            offset = (offset_w, offset_h)
            alt_text.text(offset, line, font=font, fill="black")
            line_offset += 40


def main():
    monitor = get_monitors()[0]
    monitor_w = monitor.width
    monitor_h = monitor.height
    resolution = (monitor_w, monitor_h)

    with NamedTemporaryFile(suffix=".png") as tempfile:
        try:
            image = I3LockXkcd(tempfile.name, resolution).get_image()
        except I3LockXkcdException as e:
            # Failed to get comic, just open i3lock instead
            print(e, file=sys.stderr)
            run(["i3lock"])
            sys.exit(1)

    # Write result in temporary file, loads in i3lock
    with NamedTemporaryFile(suffix=".png") as tempfile:
        image.save(tempfile.name)
        run(['i3lock', '-i', tempfile.name])


if __name__ == "__main__":
    main()

requirements.txt

olefile==0.44
Pillow==4.3.0
screeninfo==0.3
xkcd==2.4.2

xkcd.otf