#!/usr/bin/perl 
# We'd love to run this with  -T  but Utils.pm and probably DB.pm too need some work before that can happen..
########################################################################################################################
#
# Copyright (C) 2013-2014 X2Go Project - http://wiki.x2go.org
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the
# Free Software Foundation, Inc.,
# 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
#
# Copyright (C) 2013-2014 Guangzhou Nianguan Electronics Technology Co.Ltd. <opensource@gznianguan.com>
# 
#########################################################################################################################
#
# Hopefully this solves the issues pretaining to the #302 session resume bug.
# If so, we dedicate this bugfix to the Logitech D250 Keyboard who's servicelife came to an abrupt end due to this bug.
#
#########################################################################################################################
use strict;
use Sys::Hostname;
use IO::Socket;
use X2Go::Utils qw( sanitizer );
use X2Go::Server::DB qw(db_listsessions);

my $doRetryCnt = 5;
my $X2GoSID = requireX2GOSID_argvenvdie();


my @X2GoSesINFO = getSessionInfo($X2GoSID);
if (@X2GoSesINFO[1] eq $X2GoSID) {
  while ($doRetryCnt > 0) {
    $doRetryCnt--;
    if (itsUP($X2GoSesINFO[8])) {
      exit;
    } 
    sleep 1;
  }
} 


########################################################################################################
# Only SUBS past this point....: (Any Utils.pm candidates?)

sub requireX2GOSID_argvenvdie { # Return X2Go SID from either ARGV[0] or ENV.... terminates on failure.
				# If this ends up moving to Utils.pm, renaming may be a good idea.
  if (sanitizer("x2gosid",@ARGV[0])) {
    return sanitizer("x2gosid",@ARGV[0]);
  } elsif (sanitizer("x2gosid",$ENV{'X2GO_SESSION'})) {
    return sanitizer("x2gosid",$ENV{'X2GO_SESSION'});
  } else { 
    die "No X2Go Session ID in ARGV or ENV!\n"; 
  }
}

sub itsUP { # Simple sub for checking if the port is up on localhost...
	    # If this ends up moving to Utils.pm, renaming may be a good idea.
  my $portNum = sanitizer("num",$_[0]) or die "Port number not a number '$_[0]'?";
  my $socket = IO::Socket::INET->new( PeerAddr => 'localhost', PeerPort => $portNum, Proto    => 'tcp');
  if (defined $socket) { 
    print $socket "\n";
    $socket->close; 
    return 1;
  } else {
    return 0;
  }
}


sub getSessionInfo { # Simple sub to get X2GoSessionINFO from the database (kind of like greping it out of "x2golistsessions" without cranking another perl script)...
   	             # If this ends up moving to Utils.pm, renaming may be a good idea.
  my $theX2GoSID = $_[0];
  foreach  my $sessionLine (db_listsessions(hostname)) {
    if ($sessionLine =~ /$theX2GoSID/) {
      return split(/\|/,$sessionLine);
    }
  }
  return 0;
}