batbar

#!/bin/bash
if [ ! -r /sys/class/power_supply/BAT0/capacity ]; then 
	echo "Can't Access Battery"
	exit 1
fi
level=$(cat /sys/class/power_supply/BAT0/capacity)
usage () {
	echo 'usage'
	echo "  $(basename "$0") [columns] [options]"
	echo '  options:'
	echo '    -h --help      help'
	echo '    -c --clean     dont print dashes and [ ]'
}
lb="["; rb="]"; uf="-"
columns=$(($(tput cols) - 2))
for arg in "$@"; do
	case $arg in
		--help) ;&
		-h) usage; exit ;;
		--clean) ;&
		-c) lb=" "; rb=" "; uf=" ";;
		*[!0-9]*) echo "argument $arg is not a valid number";;
		*) columns="$arg";;
	esac
done
filled=$(( level * columns / 100 ))
echo -n "$lb"
for i in $(seq 1 "$columns"); do
	if [[ $i -le filled ]]; then echo -n "#"
	else echo -n "$uf"
	fi
done
echo "$rb"
exit 0