#!/bin/bash

#set -x

OMXPLAYER_DBUS_ADDR="/tmp/omxplayerdbus.${USER:-root}"
OMXPLAYER_DBUS_PID="/tmp/omxplayerdbus.${USER:-root}.pid"
export DBUS_SESSION_BUS_ADDRESS=`cat $OMXPLAYER_DBUS_ADDR`
export DBUS_SESSION_BUS_PID=`cat $OMXPLAYER_DBUS_PID`

#dbus-send --print-reply=literal --session --dest=org.mpris.MediaPlayer2.omxplayer /org/mpris/MediaPlayer2 org.mpris.MediaPlayer2.Player.$1 $2
#dbus-send --print-reply=literal --session --dest=org.mpris.MediaPlayer2.omxplayer /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Set string:"org.mpris.MediaPlayer2.Player" string:"Volume" double:"$1"
#volstr=`dbus-send --print-reply=literal --session --dest=org.mpris.MediaPlayer2.omxplayer /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Set string:"org.mpris.MediaPlayer2.Player" string:"Volume" double:"$1"`
volStr=`dbus-send --print-reply=literal --session --dest=org.mpris.MediaPlayer2.omxplayer /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Get string:"org.mpris.MediaPlayer2.Player" string:"Volume"`
vol=${volStr: 10}
echo 'current vol:'+$vol

newVol=`awk -v a=$1 -v b=$vol 'BEGIN{printf "%.1f",a+b}'`
echo 'new vol:'+$newVol

newVol=`awk -v a=$newVol 'BEGIN{printf "%s",a<0?0:a}'`
newVol=`awk -v a=$newVol 'BEGIN{printf "%s",1<a?1:a}'`
echo 'set vol:'+$newVol

volstr=`dbus-send --print-reply=literal --session --dest=org.mpris.MediaPlayer2.omxplayer /org/mpris/MediaPlayer2 org.freedesktop.DBus.Properties.Set string:"org.mpris.MediaPlayer2.Player" string:"Volume" double:"$newVol"`
echo 'response:' + $volStr