#!/bin/sh
# iTalc client launcher using avahi
# Written by Stéphane Graber <stgraber@ubuntu.com>

ICA_LTSP=`xprop -root ica_ltsp | sed 's/^.* //' 2> /dev/null`
if [ "$ICA_LTSP" = "1" ]
then
    echo "ICA already running on the thin client."
    exit 0
fi

# Set default ports
ISDPORTDEF=5800
IVSPORTDEF=5900

HOSTNAME=`hostname`
MD5_3=`md5sum /etc/italc/keys/public/teacher/key 2> /dev/null | awk '{print \$1}'`
MD5_2=`md5sum /etc/italc/keys/public/admin/key 2> /dev/null | awk '{print \$1}'`
MD5_1=`md5sum /etc/italc/keys/public/supporter/key 2> /dev/null | awk '{print \$1}'`

if [ -n "$1" ]; then
    ROLE=$1
else
    ROLE="other"
fi

# Get session number
SESSION=`echo $DISPLAY | sed -r 's/^.*:([0-9]+)(|[^0-9].*)$/\1/'`

if [ "$LTSP_CLIENT" ];
then
    echo LTSP environement detected
    PORT=`echo $LTSP_CLIENT | awk -F . '{print \$4}'`
    ISDPORT=$((($SESSION * 2 + 11) * 1000 + $PORT))
    IVSPORT=$((($SESSION * 2 + 10) * 1000 + $PORT))
else
    ISDPORT=$(($ISDPORTDEF + $SESSION))
    IVSPORT=$(($IVSPORTDEF + $SESSION))
fi

# Create script for awk
# First pattern
AWKSCRIPT='($5 ~ /^(\/usr\/bin\/|)ica/) && ($1 ~ /^[0-9]+$/)'

# Add pattern for -isdport
AWKSCRIPT="$AWKSCRIPT"' && (/[[:space:]]-isdport[[:space:]]+'$ISDPORT'([[:space:]]|$)/'
if [ "$ISDPORT" = "$ISDPORTDEF" ];
then
AWKSCRIPT="$AWKSCRIPT"' || ! /[[:space:]]-isdport[[:space:]]/'
fi
AWKSCRIPT="$AWKSCRIPT"')'

# Add pattern for -ivsport and -rfbport
AWKSCRIPT="$AWKSCRIPT"' && (/[[:space:]]-(ivs|rfb)port[[:space:]]+'$IVSPORT'([[:space:]]|$)/'
if [ "$IVSPORT" = "$IVSPORTDEF" ];
then
AWKSCRIPT="$AWKSCRIPT"' || ! /[[:space:]]-(ivs|rfb)port[[:space:]]/'
fi
AWKSCRIPT="$AWKSCRIPT"')'

# Add action: print PID only
AWKSCRIPT="$AWKSCRIPT"' {print $1}'

RUNNING_ICA=`ps x | gawk --source "$AWKSCRIPT" | sort -bg`
if [ "$RUNNING_ICA" ]
then
    for processus in $RUNNING_ICA
    do
        kill $processus
    done
    echo ICA already running, killing it.
    sleep 1s
fi

AVAHIPUBLISHSERVICE="/usr/bin/avahi-publish-service"

if [ -f $AVAHIPUBLISHSERVICE ] && [ ! -f /etc/ltsp/getltscfg-cluster.conf ]
then
    echo Announce the service on avahi
    $AVAHIPUBLISHSERVICE "italc $USER" _italc._tcp $IVSPORT $MD5_1 $MD5_2 $MD5_3 "$HOSTNAME" > /dev/null &
fi

echo Starting ICA
ica -noshm -isdport $ISDPORT -ivsport $IVSPORT -role $ROLE 2> /dev/null

if [ -f $AVAHIPUBLISHSERVICE ] && [ ! -f /etc/ltsp/getltscfg-cluster.conf ]
then
    echo Stopping avahi
    kill `ps ux | grep avahi-publish-service | grep italc | grep $IVSPORT | grep $USER | awk '{print \$2}'`
fi