#!/usr/bin/perl
use strict;

use IO::Socket;
use IO::Select;

$| = 1;

my $host = 'localhost';
my $port = '3000';
my $data;

my $socket = IO::Socket::INET->new(
  PeerAddr => $host,
  PeerPort => $port,
  Proto    => 'tcp',
  Type     => SOCK_STREAM,
  Blocking => 1,
  Timeout  => 10,
) or die "Couldn't connect to $host:$port : $!";

my $sel = IO::Select->new($socket) or die "IO::Select error $!";
  
my $request = "abcdefghijklmpnoq";
my $request_length = length($request);
print "Request:\n$request\n";
print "length(request) = $request_length\n"; # 17 

my $x = htonl($request_length);
print "x = $x\n"; # 285212672
printf("x = %x\n", $x); # 11000000

if ($sel->can_write(10)) {
  $socket->autoflush(1);
     
  # write request length
  # THIS IS WHERE I THINK SOMETHING IS GOING WRONG - THE SERVER GETS THE WRONG LENGTH HERE!!!
  $socket->send( htonl($request_length) ) or die "3a Couldn't write to socket: $!";
  
  # write request
  $socket->send( $request ) or die "3b Couldn't write to socket: $!";

  if ($sel->can_read(10)) {
    # read response length
    $socket->recv($data, 4) or die "5 Couldn't read data from server: $!";
    my $reponse_length = ntohl($data);

    if ($sel->can_read(10)) {
      # read response
      $socket->recv($data, $reponse_length) or die "6 Couldn't read data from server: $!";
      print "Response:\n$data\n";
    } else {
      print "can't read 2: $@ : $!";
    }

  } else {
    print "can't read 1: $@ : $!";
  }

} else {
  print "can't write: $@ : $!";
}

$socket->close();

sub htonl {
  my $input = shift;
  my $output = unpack('N*',pack('L*',$input));
  return $output;
}

sub ntohl {
  my $input = shift;
  my $output = unpack('L*', pack('N*', $input));
  return $output;
}