#!/bin/bash
#
# Container VNC start script
# Copyright (C) 2024 Concurrent Real Time, Inc.
# Version 1.0 2024/02/22
#
# This software may be used and distributed according to the terms of
# the GNU General Public License (GPL), version 2, or at your option
# any later version.
#
export DISPLAY=`fgrep $USER /etc/tigervnc/vncserver.users|cut -d= -f1`
export VNC_SESSION_DNO=`echo "$DISPLAY"|cut -d: -f2`
export VNC_SESSION_UID=`fgrep $USER /etc/passwd|cut -d: -f3`
export VNC_SESSION_DIR=`fgrep $USER /etc/passwd|cut -d: -f6`
export HISTCONTROL=ignoredups
export HISTSIZE=1000
export XDG_VTNR=1
export XDG_SESSION_ID=1
export XDG_SEAT=seat0
export XDG_RUNTIME_DIR=/run/user/$SESSION_UID
export LANG=en_US.UTF-8

LOGFILE="/dev/null"
myname=$(basename $0)
usage() {
   echo "Usage: $myname [-l][-c]"
   echo "   -l: Output log to /tmp/.vncserver.?.log"
   echo "   -c: Use GNOME-Classic instead of GNOME"
}
#
# Check /etc/tigervnc/vncserver.users
#
if [ -z "$DISPLAY" -o -z "$VNC_SESSION_DNO" ]
then
    echo "Error : User $USER does not exist in /etc/tigervnc/vncserver.users"
    /usr/bin/bash
    exit 1
fi
#
# Check /etc/passwd
#
if [ -z "$VNC_SESSION_UID" ]
then
    echo "Error : User $USER does not exist in /etc/passwd"
    /usr/bin/bash
    exit 2
fi
while getopts "lc" c
do
   case "$c"
   in
       c) 
        export GNOME_SHELL_SESSION_MODE=classic
        export XDG_CURRENT_DESKTOP=GNOME-Classic:GNOME
    ;;
       l) 
        LOGFILE="/tmp/.vncserver.$VNC_SESSION_DNO.log"
        touch $LOGFILE
    ;;
       \?) usage >&2; exit 1 ;;
   esac
done
trap "vncserver -kill $DISPLAY" 0 1 2 3 7 13 15
#
# Failsafe
#
vncserver -kill $DISPLAY 2>&1 > /dev/null
if [ -f /tmp/.X$VNC_SESSION_DNO-lock ]
then
    rm -f /tmp/.X$VNC_SESSION_DNO-lock 
fi
if [ -f /tmp/.X11-unix/X$VNC_SESSION_DNO ]
then
    rm -f /tmp/.X11-unix/X$VNC_SESSION_DNO 
fi
echo "--- Vncserver($DISPLAY) session started. ---" | tee -a $LOGFILE
date | tee -a $LOGFILE
ifconfig -a | tee -a $LOGFILE
echo "vncserver -list $DISPLAY" | tee -a $LOGFILE
vncserver -list $DISPLAY 2>&1 | tee -a $LOGFILE
while true
do
    vncserver $DISPLAY -xstartup /etc/X11/xinit/xinitrc -autokill -name $USER -rfbauth $VNC_SESSION_DIR/.vnc/passwd 2>&1 | tee -a $LOGFILE
    vncserver_pid=`vncserver -list 2>&1|tail -1|grep $DISPLAY|awk '{print$2}'`
    while [ -d "/proc/$vncserver_pid"  ]; do
        if [ -f "/proc/$vncserver_pid/status" ]
        then
            State=`fgrep State /proc/$vncserver_pid/status`
            case "$State" in
                *\(zombie\))
                    echo "$USER($DISPLAY) logged out."| tee -a $LOGFILE
                    break;
                ;;
                *)
                    sleep 1;
                ;;
            esac
        else
            echo "Vncserver($DISPLAY) session has been terminated." | tee -a $LOGFILE
            break;
        fi
    done
    sleep 3
    echo "--- Vncserver($DISPLAY) re-session started. ---" | tee -a $LOGFILE
    date | tee -a $LOGFILE
done