Hibernates the computer after sleeping for a while (don't use this without an SSD for obvious reasons)

auto-hibernate.sh

#!/bin/bash
# /usr/lib/systemd/system-sleep/auto-hibernate.sh
# Go to hibernate in 30 minutes
autohibernate=1800

if [ "$1" = "pre" ] && [ "$2" = "suspend" ]
then
    # Suspending, set RTC wake alarm
    rtcwake -m no -s $autohibernate
fi

if [ "$1" = "post" ] && [ "$2" = "suspend" ]
then
    # Coming out of sleep
    lidState=$(awk '{print $2}'  /proc/acpi/button/lid/LID/state)

    # Wake up no longer required
    rtcwake -m disable

    if [ "$lidState" = "closed" ]
    then
        /usr/bin/systemctl hibernate
    fi
fi