#!/bin/bash

#export DISPLAY=:0
export $(grep -z DBUS_SESSION_BUS_ADDRESS /proc/$(pgrep -u "$USER" -o startx)/environ | xargs -0)

# Battery percentage at which to notify
WARNING_LEVEL=30
CRITICAL_LEVEL=10

#BATTERY_LEVEL=$(<"/sys/class/power_supply/BAT0/capacity")
#BATTERY_DISCHARGING=$([[ $(<"/sys/class/power_supply/BAT0/status") == "Discharging" ]] && echo 1 || echo 0)
# Using acpi
BATTERY_DISCHARGING=$(acpi -b | grep "Battery 0" | grep -c "Discharging")
BATTERY_LEVEL=$(acpi -b | grep "Battery 0" | grep -P -o '[0-9]+(?=%)')

# Use temporary files to store whether a notification has already been shown (to prevent multiple notifications)
CRIT_FILE=/tmp/battery_crit
WARN_FILE=/tmp/battery_warn
FULL_FILE=/tmp/battery_full

# Reset notifications if the battery is charging/discharging
if [ "$BATTERY_DISCHARGING" -eq 1 ] && [ -f $FULL_FILE ]; then
    rm $FULL_FILE
elif [ "$BATTERY_DISCHARGING" -eq 0 ]; then
	if [ -f $WARN_FILE ]; then
		rm $WARN_FILE
	fi
	if [ -f $CRIT_FILE ]; then
		rm $CRIT_FILE
	fi
fi

# If the battery is charging and is full (and has not shown notification yet)
if [ "$BATTERY_LEVEL" -gt 95 ] && [ "$BATTERY_DISCHARGING" -eq 0 ] && [ ! -f $FULL_FILE ]; then
    notify-send "Battery Full" "Battery is fully charged." -t 1500
    touch $FULL_FILE
# If the battery is low and is not charging (and has not shown notification yet)
elif [ "$BATTERY_LEVEL" -le $CRITICAL_LEVEL ] && [ "$BATTERY_DISCHARGING" -eq 1 ] && [ ! -f $CRIT_FILE ]; then
    notify-send "⚠️ Critical Battery Level" "${BATTERY_LEVEL}% of battery remaining." -u critical -r 9991 -t 5000
    # uncomment the line below if you want to get notified at most once
    #touch $WARN_FILE
elif [ "$BATTERY_LEVEL" -le $WARNING_LEVEL ] && [ "$BATTERY_DISCHARGING" -eq 1 ] && [ ! -f $WARN_FILE ]; then
    notify-send "Low Battery" "${BATTERY_LEVEL}% of battery remaining." -u critical -r 9991 -t 1500
    # uncomment the line below if you want to get notified at most once
    #touch $WARN_FILE
fi