updates the GNOME Night Theme Switcher extension's night mode times to your local sunrise/sunset in the absence of geoclue

update-theme-switcher-sunrise-sunset.py

#!/usr/bin/python3

# run `pip3 install --user astral` or `apt install python3-astral` first
# install to `~/.local/libexec/update-theme-switcher-sunrise-sunset.py`

import json
import os
import subprocess
from pathlib import Path
from astral import Observer, sun

s = sun.sun(Observer(os.environ.get("LAT"), os.environ.get("LON"), 10), tzinfo=os.environ.get("TZ"))

for e in ("sunrise", "sunset"):
  v = s[e].hour + s[e].minute / 60.0
  subprocess.run([
    "gsettings",
    "--schemadir",
    "{}".format(
      Path("~/.local/share/gnome-shell/extensions/[email protected]/schemas").expanduser()
    ),
    "set",
    "org.gnome.shell.extensions.nightthemeswitcher.time",
    e,
    "{}".format(v),
  ])
  print("set", e, v)

update-theme-switcher-sunrise-sunset.service

# run `systemctl edit --user --force --full update-theme-switcher-sunrise-sunset.service` and paste this in

# LAT: your latitude (e.g. for New York, 40.75)
# LON: your longitude (e.g. for New York, -73.98) 
# TZ: your timezone (in tzdata format, e.g. America/New_York or Asia/Tokyo)

[Unit]
Description=Update theme switcher sunrise and sunset times
After=graphical-session.target

[Service]
Type=oneshot
Environment=LAT=40.75
Environment=LON=-73.98
Environment=TZ=America/New_York
ExecStart=python3 %h/.local/libexec/update-theme-switcher-sunrise-sunset.py

[Install]
WantedBy=graphical-session.target

update-theme-switcher-sunrise-sunset.timer

# run `systemctl edit --user --force --full update-theme-switcher-sunrise-sunset.timer` and paste this in

[Unit]
Description=Run update-theme-switcher-sunrise-sunset daily

[Timer]
AccuracySec=1h
OnCalendar=daily
OnClockChange=yes
OnTimezoneChange=yes
Persistent=yes
RandomizedDelaySec=1h

[Install]
WantedBy=timers.target