#!/bin/sh

## Backlight controller generic: use either light or xbacklight

#{{{ printhelp
printhelp () {
	printf "Backlight control interface\n"
	printf "bl -h\n"
	printf "bl [-xX] [-idg]\n"
	printf "bl [-xX] -I X\n"
	printf "bl [-xX] -D X\n"
	printf "bl [-xX] -s X\n"
	printf "\t-i)  \tincreases the backlight\n"
	printf "\t-I) X\tincreases the backlight by X percent\n"
	printf "\t-d)  \tdecreases the backlight\n"
	printf "\t-D) X\tdecreases the backlight by X percent\n"
	printf "\t-s) X\tsets the backlight to X percent\n"
	printf "\t-g)  \tgets the backlight\n"
	printf "\t-h)  \tprints this help message.\n"
	printf "\t-x)  \tuse xbacklight instead of light.\n"
	printf "\t-X)  \tdon't use xbacklight instead of light.\n"
}
#}}}

#{{{ defaults
CMD="light"
ARG="get"
AMT="1"
#}}}

#{{{ getopts2
while getopts "hxXidgI:D:s:" o; do case "${o}" in
	x) CMD="xbacklight" ;;
	X) CMD="light" ;;
	i) ARG="inc" ;;
	d) ARG="dec" ;;
	g) ARG="get" ;;
	I)
		ARG="inc"
		AMT="$OPTARG"
		;;
	D)
		ARG="dec"
		AMT="$OPTARG"
		;;
	s)
		ARG="set"
		AMT="$OPTARG"
		;;
	*) printhelp ;;
esac done
#}}}

#{{{ main
case "$CMD" in
	"light")
		case "$ARG" in
			"inc")
				light -A "$AMT%"
				;;
			"dec")
				light -U "$AMT%"
				;;
			"set")
				light -S "$AMT%"
				;;
			"get")
				light -G
				;;
		esac
		;;
	"xbacklight")
		case "$ARG" in
			"inc")
				light -A "$AMT"
				;;
			"dec")
				light -U "$AMT"
				;;
			"set")
				light -S "$AMT"
				;;
			"get")
				light -G
				;;
		esac
		;;
esac
#}}}