#!/bin/sh

set -eu

FULL_THRESHOLD=90

for battery in /sys/class/power_supply/BAT*; do
	if [ ! -f "$battery/capacity" ] || [ ! -f "$battery/status" ]; then
		continue
	fi

	read -r capacity <"$battery/capacity"
	read -r status <"$battery/status"

	if [ "$status" = "Charging" ] || ([ "$capacity" -ge "$FULL_THRESHOLD" ] && [ "$status" = "Not charging" ]); then
		prefix="AC"
	else
		prefix="BAT"
	fi
	printf '%s %s%%' "$prefix" "$capacity"

	exit 0
done

exit 1