#!/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)
			amixer set Master ${2:-5}%+ > /dev/null
			notify="Level increased to $(volume_level)%"
			;;
		dec)
			amixer set Master ${2:-5}%- > /dev/null
			notify="Level decreased to $(volume_level)%"
			;;
		set)
			amixer set Master $2% > /dev/null
			notify="Level set to $(volume_level)%"
			;;
		on)
			amixer set Master on > /dev/null
			notify="Unmuted at $(volume_level)%"
			;;
		off)
			amixer set Master off > /dev/null
			notify="Muted"
			;;
		toggle)
			case "$(volume_state)" in
				on) exec $0 off ;;
				off) exec $0 on ;;
			esac
			;;
	esac

	notify-send -n 19269 -s -t 2 -i "$(volume_icon)" "Volume" "$notify"
}

volume_level()
{
	amixer get Master | awk '/Left:/ { print $5 }' | head -n 1 | tr -d '[]%'
}

volume_state()
{
	amixer get Master | awk '/Left:/ { print $6 }' | head -n 1 | tr -d '[]'
}

volume_icon()
{
	[ "$(volume_state)" = "off" ] && printf "audio-volume-muted-panel" && return
	[ $(volume_level) -lt  1 ] && printf "audio-volume-low-zero-panel" && return
	[ $(volume_level) -lt 30 ] && printf "audio-volume-low-panel" && return
	[ $(volume_level) -lt 70 ] && printf "audio-volume-medium-panel" && return

	printf "audio-volume-high-panel"
}

usage()
{
	cat <<EOF
Usage:
	${0##*/} -h
	${0##*/} inc [level]
	${0##*/} dec [level]
	${0##*/} set <level>
	${0##*/} on
	${0##*/} off
	${0##*/} toggle

Alter the current volume level or state, and add in a notification.

Subcommands:
	inc     Increase the volume by level, defaults to 5.
	dec     Decrease the volume by level, defaults to 5.
	set     Set the volume to level.
	on      Unmute.
	off     Mute.
	toggle  Toggle between muted and unmuted state.

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

main "$@"