#!/bin/bash

# Check for dependencies
for comm in upower awk; do
	command -v upower >/dev/null 2>&1 || (echo "Error, missing command dependencies: $comm" && exit)
done

# Prepare battery informatoin
upower -i /org/freedesktop/UPower/devices/battery_BAT0 > /tmp/BAT0
[ "$(awk '/native-path/{print $2}' /tmp/BAT0)" = '(null)' ] && exit

bat_state="$(awk '/state/{print substr($2, 1, 1)}' /tmp/BAT0)"
if   [ $bat_state = 'c' ]; then bat_power_ind=''
elif [ $bat_state = 'd' ]; then bat_power_ind=''
else                            bat_power_ind=''
fi

bat_per="$(awk '/percentage/{print strtonum($2)}' /tmp/BAT0)"
bat_per=$((bat_per * 5 / 4 - 25)) # compensation for failing battery

[ $bat_state = 'd' ]                                                        \
&& bat_time="$(awk '/time to empty/{print $4 substr($5, 1, 1)}' /tmp/BAT0)" \
|| bat_time="$(awk '/time to full/ {print $4 substr($5, 1, 1)}' /tmp/BAT0)"

echo " $bat_power_ind ${bat_per}% $bat_time"

#
# Notifications
#

command -v notify-send >/dev/null 2>&1 || exit
[ ! -e '/tmp/bat_notif' ] && touch /tmp/bat_notif
bat_notif="$(cat /tmp/bat_notif)"


# Notify when battery is charged to 80%
if [ $bat_state = 'c' ]; then
	if [ "$bat_notif" != 80 ] && [ $bat_per -ge 80 ]; then
		notify-send -u normal -i battery-charging -t 999999 "Battery 80%"
		echo 80 > /tmp/bat_notif
	fi

# Notify when battery discharges to 5%, 10%, 15% and 20%
elif [ $bat_state = 'd' ]; then
	for per in 5 10 15 20; do
		if [ "$bat_notif" = $per ]; then
			break
		elif [ $bat_per -le $per ]; then
			notify-send -u critical -i battery-low -t 999999 "Battery ${per}%"
			echo $per > /tmp/bat_notif
			break
		fi
	done

# Notify when battery is full
else
	if [ "$bat_notif" != 100 ]; then
		notify-send -u normal -i battery-full -t 999999 'Fully charged!'
		echo 100 > /tmp/bat_notif
	fi
fi