#!/bin/sh

getval() {
  case $1 in
    lastfull)	fld=acpibat0.watthour0 ;;
    remain)	fld=acpibat0.watthour3 ;;
    rate)	fld=acpibat0.power0 ;;
    power)	fld=acpiac0.indicator0 ;;
  esac
  sysctl -n hw.sensors.$fld | cut -d' ' -f1
}
for v in remain lastfull rate power; do
  eval $v=`getval $v`
done
# echo $remain $lastfull $rate $power
percent=`echo "100*$remain/$lastfull"|bc -l|cut -d. -f1`
case $rate in
  0.0*)	rate=0 ;;
esac
case $power in
  Off)
	printf "AC Offline: Battery remaining %5.1f%%\n" $percent
	if [ x"$rate" = x"0" ]; then
	  echo Unknown lifetime
	else
  	  life=`echo "$remain/$rate"|bc -l`
	  hour=${life%.*} dmin=${life#*.}
	  min=`echo "0.$dmin * 60" | bc -l | cut -d. -f1`
	  printf "Discharging at %.2f(%.2f/%.2f) - ${hour:-0}h%02dm to go\n" $rate $remain $lastfull $min
	fi
	;;
  On)
	printf "AC ONline: Battery remaining %5.1f%%\n" $percent
	if [ x"$rate" = x"0" ]; then
	  echo "Last full capacity: ${lastfull}Wh"
	else
	  tf=`echo "$lastfull - $remain"|bc -l`
  	  tofull=`echo "$tf/$rate"|bc -l`
	  hour=${tofull%.*} dmin=${tofull#*.}
	  min=`echo "0.$dmin * 60" | bc -l | cut -d. -f1`
	  printf "Rate $rate to $tf ($remain/$lastfull) - "
	  printf "${hour:-0}h%02dm to full\n" $min
	fi
	;;
esac

# hw.sensors.acpibat0.volt0=11.40 VDC (voltage)
# hw.sensors.acpibat0.volt1=11.75 VDC (current voltage)
# hw.sensors.acpibat0.power0=6.59 W (rate)
# hw.sensors.acpibat0.watthour0=46.74 Wh (last full capacity)
# hw.sensors.acpibat0.watthour1=2.34 Wh (warning capacity)
# hw.sensors.acpibat0.watthour2=0.20 Wh (low capacity)
# hw.sensors.acpibat0.watthour3=30.78 Wh (remaining capacity), OK
# hw.sensors.acpibat0.watthour4=48.10 Wh (design capacity)
# hw.sensors.acpibat0.raw0=1 (battery discharging), OK
# hw.sensors.acpibat0.raw1=24 (discharge cycles)