Wall monitor power saving script (Wayland/Ubuntu 19.04)

sleepscreens.sh

#!/usr/bin/env bash

set -euo pipefail
IFS=$'\n\t'

turn_off_all_screens() {
    busctl --user set-property org.gnome.Mutter.DisplayConfig /org/gnome/Mutter/DisplayConfig org.gnome.Mutter.DisplayConfig PowerSaveMode i 3
}

turn_on_all_screens() {
    busctl --user set-property org.gnome.Mutter.DisplayConfig /org/gnome/Mutter/DisplayConfig org.gnome.Mutter.DisplayConfig PowerSaveMode i 0
}

main() {
    XDG_RUNTIME_DIR=${XDG_RUNTIME_DIR:-}
    if [[ -z "$XDG_RUNTIME_DIR" ]]; then
        export XDG_RUNTIME_DIR="/run/user/$(id -u)"
    fi

    if ! busctl --version >/dev/null 2>&1; then
        echo "busctl could not be version checked; exiting..."
        exit 1
    fi

    local WAKE_START_HOUR=8
    local WAKE_END_HOUR=18
    local SATURDAY=6

    local CURRENT_HOUR=$(date +"%k")
    local DAY_OF_WEEK=$(date +"%u")

    if [[ "$CURRENT_HOUR" -ge "$WAKE_START_HOUR" && "$CURRENT_HOUR" -lt "$WAKE_END_HOUR" && "$DAY_OF_WEEK" -lt "$SATURDAY" ]]; then
        turn_on_all_screens
    else
        turn_off_all_screens
    fi
}

main