#!/bin/sh
#
# a perl script was written by Patrick Winnertz 11.12.05
# and modified by Giovanni Gimelli - Osservatorio Tecnologico Italy
# it has been re-written by Valerio Pachera (www.linuxludus.it) as
# simple bash script
# licensed under GPL2+
# version 2.0 (21/12/2007)

# SCOPE
# The script scope is to start a ica session on different port for
# each thin client and on default ports for diskless workstation 
# and the server.
# The port number used for the thinclient will be the last part of the
# thinclient IP

# The initial script was modified by Lars Vogdt for openSUSE-Education
# at Fr 6. Jun 2008.

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

PATH=/usr/bin:/bin
ICA_CONFIG="/etc/sysconfig/ica"
ITALC_CONFIG="/etc/settings/iTALC Solutions/iTALC.conf"
ICA_BIN="/usr/bin/ica"

# Check for existence of needed config file and read it
if [ ! -r $ICA_CONFIG ]; then 
    echo "$ICA_CONFIG does not exist" >&2
    exit 6
fi

# set default values
ICA_IVSPORT="5900"
ICA_ISDPORT="5800"
ICA_USESHM="no"
ICA_USEONETYLE="no"

# Read config
. $ICA_CONFIG

ICA_OPTIONS=""

if [ "$ICA_USESHM" != "yes" ]; then
    ICA_OPTIONS="$ICA_OPTIONS -noshm"
fi
if [ "$ICA_USEONETYLE" != "yes" ]; then
    ICA_OPTIONS="$ICA_OPTIONS -onetile"
fi
if [ -n "$ICA_PARAMS" ]; then
    ICA_OPTIONS="$ICA_OPTIONS $ICA_PARAMS"
fi
if [ -n "$DISPLAY" ]; then
	DISPLAYOPT="-display $DISPLAY"
fi

function parse_ini () {
    IFS=$'\n' && ini=( $(<"$1") ) 		# convert to line-array
    ini=( ${ini[*]//;*/} ) 			# remove comments ‘;’
    ini=( ${ini[*]//\#*/} ) 			# remove comments ‘#’
    ini=( ${ini[*]/\ =\ /=} ) 			# remove anything with a space around ‘ = ‘
    ini=( ${ini[*]/#[/\}$'\n'cfg_section_} ) 	# set section prefix
    ini=( ${ini[*]/%]/ \(} )                 	# convert text2function (1)
    ini=( ${ini[*]/=/=\( } ) 			# convert item to array
    ini=( ${ini[*]/%/ \)} ) 			# close array parenthesis
    ini=( ${ini[*]/%\( \)/\(\) \{} ) 		# convert text2function (2)
    ini=( ${ini[*]/%\} \)/\}} ) 		# remove extra parenthesis
    ini=( ${ini[*]/#\ */} ) 			# remove blank lines
    ini=( ${ini[*]/#\ */} ) 			# remove blank lines with tabs
    ini[0]='' 					# remove first element
    ini[${#ini[*]} + 1]='}' 			# add the last brace
#   printf "%s\n" ${ini[*]}
    eval "$(echo "${ini[*]}")" 			# eval the result
}

function get_md5sums () {
	md5sum $1 | awk '" " { print $1}'
}

function avahi_announce () {
	IVSPORT=$1
	MD5SUMS=""
	HOST_NAME=$2
	parse_ini "$ITALC_CONFIG"
	cfg_section_keypathspublic
        MD5SUM_1="$(get_md5sums "$admin")"
	MD5SUM_2="$(get_md5sums "$supporter")"
        MD5SUM_3="$(get_md5sums "$teacher")"
	avahi-publish-service "italc $HOST_NAME" _italc._tcp $IVSPORT $MD5SUM_1 $MD5SUM_2 $MD5SUM_3 "$HOST_NAME" >/dev/null & 
}

function avahi_stop () {
	kill $(ps ux | grep avahi-publish-service | grep italc | grep $IVSPORT | grep $HOSTNAME | awk '" " { print $2 }')
}


if [ -x "$ICA_BIN" ]; then
	if [ -f /etc/ltsp_chroot ]; then
	        IP=$(ip addr show | grep " inet " | grep -v 127.0.0 | head -n1 | awk '{print \$2}' | sed "s/\/.*//")
		HOST_NAME=$(hostname)
	fi
    # ends any previous ica session of the user that is running the script
    # FIXME: killall --user $(whoami) ica 2>/dev/null; <<- better?
	RUNNING_ICA=$(ps ux | awk '" " { print $2" "$11 }' | grep -E "^[0-9].*ica" | awk '" " { print $1 }')
	if [ -n "$RUNNING_ICA" ]; then
	    for process in $RUNNING_ICA; do
			kill $process
		done
		sleep 1
	fi

    if [ x"$ICA_ENABLE" = x"yes" ]; then
        # $LTSP_CLIENT is empty if the script is called on the server or a
        # Diskless Workstation.
        # That's true only if the script is executed after logged in the
        # desktop manager.
	if [ "$LTSP_CLIENT" ]; then
			PORT=$(echo $LTSP_CLIENT | awk -F . '{print $4}')
			ICA_IVSPORT=$((10000 + $PORT))
			ICA_ISDPORT=$((11000 + $PORT))

			IP="$LTSP_CLIENT"
			HOST_NAME="$IP ($USER)"
        else
	    HOST_NAME=$(hostname)
        fi
	#start ICA service
        $ICA_BIN $ICA_OPTIONS -ivsport $ICA_IVSPORT -isdport $ICA_ISDPORT $DISPLAYOPT &

	if [ -x /usr/bin/avahi-publish-service ]; then
	  	if [ -f /var/run/avahi-daemon/pid ]; then
			avahi_stop
			avahi_announce $ICA_IVSPORT $HOST_NAME
		fi
	fi
    fi
else
	echo "$ICA_BIN doesn't exist or is not executable" >&2
	exit 1
fi