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#!/opt/perl/bin/perl
use strict;
use utf8;
use AnyEvent;
use AnyEvent::XMPP::Client;
use AnyEvent::XMPP::Util qw/simxml/;
use AnyEvent::XMPP::Ext::Disco;

my $j = AnyEvent->condvar;
my $cl = AnyEvent::XMPP::Client->new;

$cl->add_account ('net_xmpp2@jabber.org', 'test');

my $max_size      = 100000;
my $first_size    = $max_size;
my $last_nok_size = $max_size;
my $last_ok_size  = 0;
my $delta         = 10;

$cl->reg_cb (
   session_ready => sub {
      my ($cl, $acc) = @_;
      my $con = $acc->connection;

      if (($last_nok_size - $last_ok_size) < $delta) {
         print "Found limit in delta range: $last_ok_size for ".$acc->jid."\n";
         $con->disconnect ("found limit");
         return 0;
      }

      $con->send_iq (set => sub {
         my ($w) = @_;
         simxml ($w,
            defns => 'jabber:iq:private',
            node  => {
               name   => 'query',
               ns     => 'jabber:iq:private',
               childs => [
                  { name => "test", dns => "test:fe", childs => [ "A" x $first_size ] },
               ]
            }
         );
         print "Trying $first_size...\n";
      }, sub {
         my ($n, $e) = @_;
         if ($e) {
            die "iq private error: " . $e->string . "\n";
         } else {
            $con->send_iq (get => sub {
               my ($w) = @_;
               simxml ($w,
                  defns => 'jabber:iq:private',
                  node => {
                     name => 'query',
                     ns => 'jabber:iq:private',
                     childs => [ { name => 'test', dns => 'test:fe' } ] 
                  }
               );
            }, sub {
               my ($n, $e) = @_;
               if ($e) { 
                  $con->disconnect ("bad iq reply");
               } else {
                  my ($q) = $n->find_all ([qw/jabber:iq:private query/],
                                          [qw/test:fe test/]);
                  my $len = length $q->text;
                  if ($len == $first_size) {
                     print "$len seems to be ok!\n";
                     $last_ok_size = $first_size;
                     $first_size = $last_ok_size + ($last_nok_size - $last_ok_size) / 2;
                     $first_size = int ($first_size);
                     $con->disconnect ("retry");
                  } else {
                     $con->disconnect ("too short iq reply");
                  }
               }
            });
         }
      }, timeout => 1000000);

      1
   },
   stream_error => sub {
      my ($cl, $acc, $err) = @_;
      print "STREAM ERROR: [" . $err->string . "] at $first_size, retry...\n";
      1
   },
   connect_error => sub {
      my ($cl, $acc, $err) = @_;
      print "Connect error ".$acc->jid.": $err\n";
      1
   },
   disconnect => sub {
      my ($cl, $acc, $host, $port, $msg) = @_;
      if ($msg eq 'found limit') { $j->broadcast }
      elsif ($msg ne 'retry') {
         $last_nok_size = $first_size;
         $first_size = $last_ok_size + ($last_nok_size - $last_ok_size) / 2;
         $first_size = int ($first_size);
         print "disconnect got ($msg), retry with $first_size\n";
      }
      $cl->update_connections; # reconnect !
      1
   },
   message => sub {
      my ($cl, $acc, $msg) = @_;
      print "message from: " . $msg->from . ": " . $msg->any_body . "\n";
      1
   }
);

$cl->start;
$j->wait;