#!/usr/bin/perl -w
#tcpserver.pl
use strict;
use Data::Dumper;
use IO::Socket::INET;
# flush after every write
$| = 1;
my (@arr,@art,%hsh,$cin,$tims,$status,$data,%vrf,$x,$start);
my ($socket,$client_socket,@client_reply,@client_verify,$client_reply);
my @hash=({port=>'',tim=>''});
my ($peer_address,$peer_port);
my $times_connect=0;
# creating object interface of IO::Socket::INET modules which internally does
# socket creation, binding and listening at the specified port address.
$socket = new IO::Socket::INET (
#LocalHost => '127.0.0.1',
LocalPort => '5000',
Proto => 'tcp',
Listen => 5,
Reuse => 1
) or die "ERROR in Socket Creation : $!\n";
my $timeData = scalar(localtime);
print $timeData."\n"; 
print "SERVER Waiting for client connection on port 5000";
my $times_connected=0;
$start=1;
while(1)
{
	# waiting for new client connection.
	$client_socket = $socket->accept();
	# get the host and port number of newly connected client.
	$peer_address = $client_socket->peerhost();
	$peer_port = $client_socket->peerport();
	push @arr,$peer_port;
	$hsh{$peer_port}=1;
	
	if($start eq 1) # The very first client.
	{	
		$status=1; 					
		# get your own MD5
	}
	if($start >1)
	{
			$status=$client_reply;
												  #It has to write its own this time.
	}
	print "\nAccepted New Client Connection[$start] From : $peer_address, $peer_port\n at".scalar(localtime);
	# write operation on the newly accepted client.
	print $client_socket "$status\n";
	$data = <$client_socket>;
	chomp($data);
	print "Received from Client :",$data;
	push @client_reply,$data;
	$client_reply.="$data {}";
	print "\n\n LIST->$client_reply";
	$start++;
	}
$socket->close();

##</code><code>##

#!/usr/bin/perl
#tcpclient.pl
use strict;
use IO::Socket::INET;
use Digest::MD5 qw(md5 md5_hex md5_base64);

# flush after every write
$| = 1;

my ($socket,$client_socket,$status,$data,@info,$file,$md_self,$x,$i,$a1,@a1,@a2);

# creating object interface of IO::Socket::INET modules which internally creates
# socket, binds and connects to the TCP server running on the specific port.
$socket = new IO::Socket::INET (
PeerHost => '127.0.0.1',
PeerPort => '5000',
Proto => 'tcp',
) or die "ERROR in Socket Creation : $!\n";

print "TCP Connection Success.\n";
# read the socket data sent by server.
$data = <$socket>;
# we can also read from socket through recv()  in IO::Socket::INET
# $socket->recv($data,1024);
print "Received from Server : ",$data;
chomp($data);
if($data eq 1)
	{
		$file=createRandom();
		$md_self= md5_hex($file);
		open(FL,'>disk1.txt');
		print FL $file;
		close FL;
		open(FL,'disk1.txt');
		$_=<FL>;
		close FL;
		if(md5_hex($_) eq $md_self)
		{
			$status="$file $md_self"; #send the file address and its MD5: 		}
	sleep(20);
}
	else
	{ chomp($data);
		$x=0;
		@a1=split(" {}",$data);
		for $i(0..($#a1))
		{
			@a2=();
			@a2=split(' ',$a1[$i]);
			if(md5_hex($a2[0]) eq $a2[1])
			{
				$x++;
			}
			}
			if ($x eq ($#a1+1))
			{
				$file=createRandom();
		$md_self= md5_hex($file);
		open(FL,'>disk1.txt');
		print FL $file;
		close FL;
		open(FL,'disk1.txt');
		$_=<FL>;
		close FL;
		if(md5_hex($_) eq $md_self)
		{
			$status=$file.' '.$md_self; #send the file address and its MD5.
		}
			}
			else 
			{
				$status="Could'nt verfiy";
			}
		}
	
	
# write on the socket to server.
print $socket "$status\n" ;
# we can also send the data through IO::Socket::INET module,
# $socket->send($data);

#sleep (10);
$socket->close();

####
#To create random characters
####
sub createRandom
{
    my ($randChars, $number, $output, $new, $i);

    # create string in loop (each char is a loop iteration)
    for ($i = 0; $i < 5; $i++)
    {

        # get a random number for each digit
        $number = int(rand(36));

        # convert to a number or a letter depending on value
        if ($number < 10)
        {

            # number -> ASCII number
            $output = $number + 48;
        }
        else
        {

            # letter -> ASCII letter
            $output = $number + 87;
        }

        # make the ASCII number a character and append to string
        $new       = chr($output);
        $randChars = "$randChars$new";
    }
    return ($randChars);
}