#!/bin/bash
# From: http://www.thinkwiki.org/wiki/Sample_Fn-F7_script
#
# External output may be "VGA" or "VGA-0" or "DVI-0" or "TMDS-1"
EXTERNAL_OUTPUT="VGA1"
INTERNAL_OUTPUT="LVDS1"
# EXTERNAL_LOCATION may be one of: left, right, above, or below
EXTERNAL_LOCATION="right"
 
case "$EXTERNAL_LOCATION" in
       left|LEFT)
               EXTERNAL_LOCATION="--left-of $INTERNAL_OUTPUT"
               ;;
       right|RIGHT)
               EXTERNAL_LOCATION="--right-of $INTERNAL_OUTPUT"
               ;;
       top|TOP|above|ABOVE)
               EXTERNAL_LOCATION="--above $INTERNAL_OUTPUT"
               ;;
       bottom|BOTTOM|below|BELOW)
               EXTERNAL_LOCATION="--below $INTERNAL_OUTPUT"
               ;;
       *)
               EXTERNAL_LOCATION="--left-of $INTERNAL_OUTPUT"
               ;;
esac
 
function screen_external(){
       xrandr --output $INTERNAL_OUTPUT --off
       xrandr --output $EXTERNAL_OUTPUT --auto
}
 
function screen_internal(){
       xrandr --output $EXTERNAL_OUTPUT --off
       xrandr --output $INTERNAL_OUTPUT --auto
}
 
function screen_mirror(){
       xrandr --output $INTERNAL_OUTPUT --auto
       xrandr --output $EXTERNAL_OUTPUT --auto --same-as $INTERNAL_OUTPUT
}
 
function screen_both(){
       xrandr --output $INTERNAL_OUTPUT --auto
       xrandr --output $EXTERNAL_OUTPUT --auto $EXTERNAL_LOCATION
}
 
function screen_toggle(){
       # Figure out current state
       INTERNAL_STATE=$(xrandr | grep ^$INTERNAL_OUTPUT | grep con | sed "s/.*connected //" | sed "s/(.*//")
       EXTERNAL_STATE=$(xrandr | grep ^$EXTERNAL_OUTPUT | grep con | sed "s/.*connected //" | sed "s/(.*//")
       
       if [ -z "$INTERNAL_STATE" ]; then
         STATE="external"
       elif [ -z "$EXTERNAL_STATE" ]; then
         STATE="internal"
       else
         INTERNAL_STATE=$(echo $INTERNAL_STATE | sed "s/[0-9]*x[0-9]*//")
         EXTERNAL_STATE=$(echo $EXTERNAL_STATE | sed "s/[0-9]*x[0-9]*//")
         if [ "$INTERNAL_STATE" = "$EXTERNAL_STATE" ]; then
           STATE="mirror"
         else
           STATE="both"
         fi
       fi
 
       case "$STATE" in
               internal)
                       screen_mirror
                       ;;
               mirror)
                       screen_external
                       ;;
               external)
                       screen_both
                       ;;
               both)
                       screen_internal
                       ;;
               *)
                       screen_internal
                       ;;
       esac
}

# based on /etc/acpi/screenblank.sh (Ubuntu 7.10)
# . /usr/share/acpi-support/power-funcs         # for getXuser
getXuser() {
       user=`finger| grep -m1 ":$displaynum " | awk '{print $1}'`
       if [ x"$user" = x"" ]; then
               user=`finger| grep -m1 ":$displaynum" | awk '{print $1}'`
       fi
       if [ x"$user" != x"" ]; then
               userhome=`getent passwd $user | cut -d: -f6`
               export XAUTHORITY=$userhome/.Xauthority
       else
               export XAUTHORITY=""
       fi
}
# end of getXuser from /usr/share/acpi-support/power-funcs
#
for x in /tmp/.X11-unix/*; do
   displaynum=`echo $x | sed s#/tmp/.X11-unix/X##`
   getXuser;
   if [ x"$XAUTHORITY" != x"" ]; then
       export DISPLAY=":$displaynum"
      screen_toggle
   fi
done