#!/usr/bin/env sh
set -e

battery_capacity=$(cat "/sys/class/power_supply/${1}/capacity")

if   [ "$battery_capacity" -lt 25  ]; then echo critical
elif [ "$battery_capacity" -lt 50  ]; then echo low
elif [ "$battery_capacity" -lt 75  ]; then echo medium
elif [ "$battery_capacity" -lt 100 ]; then echo high
else                                       echo full
fi