#!/usr/bin/env bash
# Craig Jennings <c@cjennings.net>
# DWM convenience script for changing backlight
# depends on xbacklight

increment=10

case $1 in
	"max")
		sudo xbacklight -set 100%;
		;;
	"min")
		sudo xbacklight -set 5%;
		;;
	"up")
		# get current setting as an int
		current=$( printf "%.0f" "$(xbacklight -get)" )

		# add the increment
		newvalue=$(("$current" + "$increment"))

		# don't let the brightness go above 100
		[ "$newvalue" -ge 100 ] && 	newvalue=100;

		# set the value
		xbacklight -set "$newvalue";
		;;
	"down")
		current=$( printf "%.0f" "$(xbacklight -get)" )
		newvalue=$(("$current" - "$increment"))
		[ "$newvalue" -le 5 ] && 	newvalue=5;
		xbacklight -set "$newvalue";
		;;
esac
newvalue=$( printf "%.0f" "$(xbacklight -get)")
notify-send "backlight" "backlight now set to $newvalue"