#!/bin/bash

# by TeknoHog (of iki.fi) for Fujitsu Siemens Amilo Pro V2020

# Suspends the machine to disk when running low on battery power.

LOGFILE=/root/test.log

# If we're online, don't bother even if the capacity is low.
ONLINE=`cat /proc/acpi/ac_adapter/AC0/state | grep on-line`
if [ -n "$ONLINE" ]; then exit; fi

# TODO: parse the "%n mAh" part for more robust results, instead of awk
CAPA=`grep remaining /proc/acpi/battery/BAT0/state | awk '{print $3}'`
LOW=`grep "design capacity low" /proc/acpi/battery/BAT0/info | awk '{print $4}'`

# Do something to the numbers before comparison. 
# If the variables are empty, the evaluation is true :(

if [ $((CAPA+2)) -lt $((LOW+1)) ]; then
    
    echo Hibernating on `date` >> $LOGFILE
    echo "capa: " $CAPA >> $LOGFILE
    echo "low: " $LOW >> $LOGFILE
    echo "event info:" $@ >> $LOGFILE

    /usr/sbin/hibernate
fi