#!/usr/bin/perl

# This is a simple IRC bot that just rot13 encrypts public messages.
# It responds to "rot13 <text to encrypt>".

use warnings;
use strict;

use POE;
use POE::Component::IRC;

sub CHANNEL () { "##" }

# Create the component that will represent an IRC network.
my ($irc) = POE::Component::IRC->spawn();

# Create the bot session.  The new() call specifies the events the bot
# knows about and the functions that will handle those events.
POE::Session->create(
    inline_states => {
        _start     => \&bot_start,
        irc_001    => \&on_connect,
        irc_public => \&on_public,
    },
);

# The bot session has started.  Register this bot with the "magnet"
# IRC component.  Select a nickname.  Connect to a server.
sub bot_start {
    my $kernel  = $_[KERNEL];
    my $heap    = $_[HEAP];
    my $session = $_[SESSION];

    $irc->yield( register => "all" );

    my $nick = 'Perlbot' . $$ % 1000;
    $irc->yield( connect =>
          { Nick => $nick,
            Username => 'PerlBot',
            Ircname  => 'Perlbot',
            Server   => 'irc.bluehell.org',
            Port     => '6667',
          }
    );
}

# The bot has successfully connected to a server.  Join a channel.
sub on_connect {
    $irc->yield( join => CHANNEL );
}

# The bot has received a public message.  Parse it for commands, and
# respond to interesting things.
sub on_public {
    my ( $kernel, $who, $where, $msg ) = @_[ KERNEL, ARG0, ARG1, ARG2 ];
    my $nick = ( split /!/, $who )[0];
    my $channel = $where->[0];

    my $ts = scalar localtime;
    print " [$ts] <$nick:$channel> $msg\n";

    if ( my ($rot13) = $msg =~ /^rot13 (.+)/ ) {
        $rot13 =~ tr[a-zA-Z][n-za-mN-ZA-M];

        # Send a response back to the server.
        $irc->yield( privmsg => CHANNEL, $rot13 );
    }
}

# Run the bot until it is done.
$poe_kernel->run();
exit 0