#!/bin/sh

# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your option) any
# later version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.

main()
{
	# Handle opts
	while getopts ":h" opt
	do
		case "$opt" in
			h) usage && exit 0 ;;
			*)
				printf "Invalid option passed: %s\n" "$OPTARG" >&2
				;;
		esac
	done

	shift $(( OPTIND - 1 ))

	[ $# -lt 1 ] && usage && exit 1

	case "$1" in
		inc)
			xbacklight -inc ${2:-5}
			notify="Brightness increased to $(brightness_level)%"
			;;
		dec)
			xbacklight -dec ${2:-5}
			notify="Brightness lowered to $(brightness_level)%"
			;;
	esac

	notify-send -n 57492 -s -t 2 -i "$(brightness_icon)" "Backlight" "$notify"
}

brightness_level()
{
	xbacklight -get
}

brightness_icon()
{
	[ $(brightness_level) -lt 10 ] && printf "notification-display-brightness-off" && return
	[ $(brightness_level) -lt 35 ] && printf "notification-display-brightness-low" && return
	[ $(brightness_level) -lt 70 ] && printf "notification-display-brightness-medium" && return
	[ $(brightness_level) -lt 95 ] && printf "notification-display-brightness-high" && return

	printf "notification-display-brightness-full"
}

usage()
{
	cat <<EOF
Usage:
	${0##*/} -h

Nondescript

Options:
	-h  Show this help text and exit.
EOF
}

main "$@"