#!/usr/bin/env sh
# An adaptation of https://github.com/porras/i3-keyboard-layout/blob/master/i3-keyboard-layout by MYDavoodeh
set -e

get_kbdlayout() { setxkbmap -query | grep -oP 'layout:\s*\K(\w+)' ;}

set_kbdlayout() {
	# FIXME what to do for variants?
	setxkbmap "$1"
	pgrep i3status | xargs --no-run-if-empty kill -s USR1 # to tell i3status to update
}

cycle() { #TODO: Optimize cycling time
	current_layout=$(get_kbdlayout)
	eval last="\$$#"
	# If current_layout is the last one OR current_layout is not in the given layouts, set the first one in cycle as the initiator. Else find the next.
	{ [ "$last" = "$current_layout" ] || ! echo "$*" | grep -qo "$current_layout" ;} && set_kbdlayout "$1" || set_kbdlayout "$(echo "$*" | cut -d' ' -f "$#")"
}


subcommand="$1"
helpmsg="Please specify one of: get, set <layout> or cycle <layout1> <layout2> ... <layoutN>"

shift || (echo "$helpmsg" && exit)
case $subcommand in
	"get") echo get_kbdlayout ;;
	"set") set_kbdlayout "$1" ;;
	"cycle") cycle "$@" ;;
	*) echo "Fatal: Command $subcommand not found.\n$helpmsg" ;;
esac

pkill -RTMIN+13 i3blocks # for [lang] in i3blocks