#!/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 () { "#Freedom" }

# Create the component that will represent an IRC network.
POE::Component::IRC->new("magnet");

# 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];

    $kernel->post( magnet => register => "all" );

    my $nick = 'usepoe' . $$ % 1000;
    $kernel->post( magnet => connect =>
          { Nick => 'JPPLAY-bot',
            Username => 'cookbottest',
            Ircname  => 'POE::Component::IRC cookbook bot',
            Server   => 'irc.radio-freedom.com',
            Port     => '6667',
          }
    );
}

# The bot has successfully connected to a server.  Join a channel.
sub on_connect {
    $_[KERNEL]->post( magnet => join => CHANNEL );
}

# Once connected, start a periodic timer to ping ourselves.  This
# ensures that the IRC connection is still alive.  Otherwise the TCP
# socket may stall, and you won't receive a disconnect notice for
# up to several hours.
sub bot_connected {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];


    $heap->{seen_traffic} = 1;
    $kernel->delay( autoping => 300 );
}

# Ping ourselves, but only if we haven't seen any traffic since the
# last ping.  This prevents us from pinging ourselves more than
# necessary (which tends to get noticed by server operators).
sub bot_do_autoping {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];
    $kernel->post( poco_irc => userhost => "my-nickname" )
      unless $heap->{seen_traffic};
    $heap->{seen_traffic} = 0;
    $kernel->delay( autoping => 300 );
}

# 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.
        $kernel->post( magnet => privmsg => CHANNEL, $rot13 );
    }
}

# Reconnect in 60 seconds.  Don't ping while we're disconnected.  It's
# important to wait between connection attempts or the server may
# detect "abuse".  In that case, you may be prohibited from connecting
# at all.
sub bot_reconnect {
    my $kernel = $_[KERNEL];
    $kernel->delay( autoping => undef );
    $kernel->delay( connect  => 60 );
}

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

POE::Session->create(
    inline_states => {
        irc_disconnected => \&bot_reconnect,
        irc_error        => \&bot_reconnect,
        irc_socketerr    => \&bot_reconnect,

        connect  => \&bot_connect,
        _start   => \&bot_start,
        autoping => \&bot_do_autoping,
        irc_001  => \&bot_connected,
    },
);

# Initialize the bot, and connect to a server.
sub bot_start {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];

    # Set up the bot here.
    ...;

    # Connect.
    $kernel->yield("connect");
}

# The connect code is in its own handler so it can be reached from two
# places: _start, and bot_reconnect.
sub bot_connect {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];

    # Consider performing server rotation here.  A server may not be
    # back right away, and having alternatives means your bot will be
    # back in business sooner.
    ...;

    # Do the connection.
    $kernel->post( poco_irc => connect => \%parameters );
}

# Once connected, start a periodic timer to ping ourselves.  This
# ensures that the IRC connection is still alive.  Otherwise the TCP
# socket may stall, and you won't receive a disconnect notice for
# up to several hours.
sub bot_connected {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];

    # Join channel(s), set user modes, etc.
    ...;

    $heap->{seen_traffic} = 1;
    $kernel->delay( autoping => 300 );
}

# Ping ourselves, but only if we haven't seen any traffic since the
# last ping.  This prevents us from pinging ourselves more than
# necessary (which tends to get noticed by server operators).
sub bot_do_autoping {
    my ( $kernel, $heap ) = @_[ KERNEL, HEAP ];
    $kernel->post( poco_irc => userhost => "my-nickname" )
      unless $heap->{seen_traffic};
    $heap->{seen_traffic} = 0;
    $kernel->delay( autoping => 300 );
}

# Reconnect in 60 seconds.  Don't ping while we're disconnected.  It's
# important to wait between connection attempts or the server may
# detect "abuse".  In that case, you may be prohibited from connecting
# at all.
sub bot_reconnect {
    my $kernel = $_[KERNEL];
    $kernel->delay( autoping => undef );
    $kernel->delay( connect  => 60 );
}

POE::Session->create(
    inline_states => {
        irc_disconnected => \&bot_reconnect,
        irc_error        => \&bot_reconnect,
        irc_socketerr    => \&bot_reconnect,

        connect  => \&bot_connect,
        _start   => \&bot_start,
        autoping => \&bot_do_autoping,
        irc_001  => \&bot_connected,
    },
);