# $Id: Announcer.pm 1354 2006-06-14 00:27:26Z rvosa $
# Subversion: $Rev: 117 $

# Copyright (c) 1997 Lunatech Research / Bart Schuller <schuller@lunatech.com>
# See the file "Artistic" in the distribution for licensing and
# (lack of) warranties.
use Log::Log4perl;
use COPE::CORBA::ORB;
Log::Log4perl::init( COPE::CORBA::ORB->LOGPERLCONF );

package COPE::Announcer;
use strict;
use IO::Handle;
use Socket;
use COPE::CORBA::ORB;

my $logger = Log::Log4perl::get_logger('COPE.Announcer');

# Subs
sub announce {
    $logger->info("Announcing service");
    my ( $name, $value ) = @_;
    my ( $msg, $index ) = ( 'ADD ', 4 );
    CORBA::ORB::_marshal_string( \$msg, \$index, 0, $name );
    CORBA::ORB::_marshal_string( \$msg, \$index, 0, $value );
    my $broadcaster = new COPE::Announcer;
    $broadcaster->shout();
    return $broadcaster->send_and_get_message($msg);
}

sub resolve {
    $logger->info("Resolving service");
    my ($name) = @_;
    my ( $msg, $index ) = ( 'GET ', 4 );
    CORBA::ORB::_marshal_string( \$msg, \$index, 0, $name );
    my $broadcaster = new COPE::Announcer;
    $broadcaster->shout();
    $msg = $broadcaster->send_and_get_message($msg);
    return undef if !defined $msg;
    $index = 0;
    my $value = CORBA::ORB::_unmarshal_string( \$msg, \$index, 0 );
    return $value;
}

sub daemon {
    $logger->info("Starting daemon");
    my %db;
    my $listener = new COPE::Announcer;
    $listener->listen();
    while (1) {
        my $msg = $listener->get_message(undef);
        next if !$msg;
        my $cmd = substr( $msg, 0, 4 );
        my $index = 4;
        if ( $cmd eq 'ADD ' ) {
            my $name  = CORBA::ORB::_unmarshal_string( \$msg, \$index, 0 );
            my $value = CORBA::ORB::_unmarshal_string( \$msg, \$index, 0 );
            $db{$name} = $value;
            $listener->send_message('ADDED');
            next;
        }
        if ( $cmd eq 'GET ' ) {
            my $name = CORBA::ORB::_unmarshal_string( \$msg, \$index, 0 );
            $msg   = '';
            $index = 0;
            CORBA::ORB::_marshal_string( \$msg, \$index, 0, $db{$name} );
            $listener->send_message($msg);
            next;
        }
    }
}

# Class methods
sub new {
    $logger->info("Creating new announcer");
    my ($class) = @_;
    my $self = { sock => new IO::Handle };
    socket( $self->{sock}, PF_INET, SOCK_DGRAM, getprotobyname('udp') )
      or ( $logger->fatal($!) && die "socket: $!" );
    return bless $self, $class;
}

# Object methods
sub listen {
    $logger->info("Listening");
    my ($self) = @_;
    bind( $self->{sock}, scalar sockaddr_in( 3228, INADDR_ANY ) )
      or ( $logger->fatal($!) && die "bind: $!" );
}

sub shout {
    $logger->info("Shouting");
    my ($self) = @_;
    $self->{'peer'} = sockaddr_in( 3228, INADDR_BROADCAST );
    setsockopt( $self->{'sock'}, SOL_SOCKET, SO_BROADCAST, 1 )
      or ( $logger->fatal($!) && die "setsockopt: $!" );
}

sub get_message {
    $logger->info("Getting message");
    my ( $self, $timeout ) = @_;
    my ( $msg, $rout );
    my $rin = '';
    vec( $rin, fileno( $self->{'sock'} ), 1 ) = 1;
    select( $rout = $rin, undef, undef, $timeout );
    if ( vec( $rout, fileno( $self->{'sock'} ), 1 ) ) {
        $self->{'peer'} = recv $self->{'sock'}, $msg, 4096, 0;
        return $msg;
    }
    else {
        return undef;
    }
}

sub send_message {
    $logger->info("Sending message");
    my ( $self, $msg ) = @_;
    send( $self->{sock}, $msg, 0, $self->{peer} ) or ( $logger->fatal($!) && die "send: $!\n" );
}

sub send_and_get_message {
    $logger->info("Sending and getting message");
    my ( $self, $in ) = @_;
    my $out;
    for ( my $i = 0 ; $i < 10 ; $i++ ) {
        $self->send_message($in);
        last if defined( $out = $self->get_message(1) );
    }
    return $out;
}
1;

__END__

=head1 NAME

COPE::Announcer

A class to ...

=head1 SYNOPSIS

use COPE::Announcer;

=head1 DESCRIPTION

The COPE::Announcer class implements ...

=head1 OPTIONS

 -D            - show debugging information
 -h            - show help
 -v            - show version
 Other options ...

=head1 SUBROUTINES

=head2 announce

Parameters:
    name
    value

Insert description of subroutine here...

=head2 resolve

Parameters:
    name

Insert description of subroutine here...

=head2 daemon

Parameters:
    none

Insert description of subroutine here...

=head2 new (constructor)

Parameters:
    class

Insert description of constructor here...

=head2 listen (method)

Parameters:
    none

Insert description of method here...

=head2 shout (method)

Parameters:
    none

Insert description of method here...

=head2 get_message (method)

Parameters:
    timeout

Insert description of method here...

=head2 send_message (method)

Parameters:
    msg

Insert description of method here...

=head2 send_and_get_message (method)

Parameters:
    in

Insert description of method here...

=head1 FILES

Files used by the COPE::Announcer class ...

=head1 SEE ALSO

Related information ...

=head1 WARNINGS

...

=head1 NOTES

...

=head1 BUGS

What?

=cut
=head2 announce

Parameters:
    name
    value

Insert description of subroutine here...

=head2 resolve

Parameters:
    name

Insert description of subroutine here...

=head2 daemon

Parameters:
    none

Insert description of subroutine here...

=head2 new (constructor)

Parameters:
    class

Insert description of constructor here...

=head2 listen (method)

Parameters:
    none

Insert description of method here...

=head2 shout (method)

Parameters:
    none

Insert description of method here...

=head2 get_message (method)

Parameters:
    timeout

Insert description of method here...

=head2 send_message (method)

Parameters:
    msg

Insert description of method here...

=head2 send_and_get_message (method)

Parameters:
    in

Insert description of method here...