#!/bin/bash
#
# kbdd_layout is a script that parse layout with kbdd in real time
# Copyright (C) 2016,2019 Anton Karmanov <bergentroll@insiberia.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Matches first 3 letters of layout name.
MATCH='\w{3}'

# Matches short layout name.
#MATCH='\w*'

# Matches full layout name.
#MATCH='\w*(\s\(.*\))?'

# Restart kbdd to apply layout changes on block reload.
killall kbdd 2>/dev/null
kbdd >/dev/null || exit 1

# Get initial state of layout
N=$( dbus-send --print-reply=literal --dest=ru.gentoo.KbddService\
    /ru/gentoo/KbddService ru.gentoo.kbdd.getCurrentLayout 2>/dev/null |\
    sed -un 's/^.*uint32 //p' )

# In case dbus service wasn't available yet, poll until service is ready.
while [[ -z "$N" ]]; do
    sleep .1
    N=$( dbus-send --print-reply=literal --dest=ru.gentoo.KbddService\
        /ru/gentoo/KbddService ru.gentoo.kbdd.getCurrentLayout 2>/dev/null |\
        sed -un 's/^.*uint32 //p' )
done
dbus-send --print-reply=literal --dest=ru.gentoo.KbddService \
  /ru/gentoo/KbddService ru.gentoo.kbdd.getLayoutName uint32:"$N" |\
  grep -Po "${MATCH}" | head -n1

# Parse dbus output.
dbus-monitor "interface='ru.gentoo.kbdd',member='layoutNameChanged'" |\
  grep -Po --line-buffered "(?<=string \")${MATCH}"