Several friends of mine and myself are writing small utility programs for our napster network in the form of "bots" (almost exactly like their IRC equivalent). Since we're all capable perl programmers, I thought it would be best if we could share our code, and move functions from one bot to the other, or write a new function and have it work in another bot. Write once, run everywhere, right?

So I am writing this API for a MP3::Napster bot. Pretty simple code, but I am trying to make it robust and a pleasure to write code for. No use in making something _else_ we dont want to code in.

I'd like it if a few monks could look over the code and make some observations before I plow into the real guts of the API.

Thanks,
brother dep.

package Bot;

require 5.6; # update or die.

use warnings;
use strict;
use Carp;
use Data::Dumper;

use MP3::Napster;
use POSIX;

#########################################################
##                    data, mkay?                      ##
#########################################################

# warnings and debug level, respectively...
our ($squawk, $dl);
$squawk = 1;
$dl = 1;

# this is where we are leaving subs we import.
our %importedMethods = ();

# information on the bot
our %botInfo = ();

# information for our hackers
our %messages = ();

# our bot.
our $bot;

#########################################################
##                    subs, mkay?                      ##
#########################################################

# change the debug level
sub debug {
  $dl = shift;
}

# convert and verify the hash that the programmer gives us for install
+ation
# into the bot.
sub convertAttributes {
  my %allowedAttributes = (
    bot_name => qr/[:alnum:]{1,16}/,
    prefix => qr/[:alnum:]{1}/,
    server => qr/[:alnum:]+/,
    password => qr/[:alnum:]{32}/,
    port => qr/\d{1,5}/,
    channel => qr/#?[:alnum:]{1,16}/,
  );

  my %incoming = %{ shift() };
  my @badAttributes =
    grep { $incoming{$_} !~ $allowedAttributes{$_} } keys %incoming;

  if (scalar @badAttributes == 0) {
    %botInfo = %incoming;
    return 1;
  } else {
    return 0;
  }
}

# handle public messages
sub pubHandler {
  my $botCommands = join '|', keys %importedMethods;
  $botCommands = qr{($botCommands)};
  my $self = shift;
  my ($ec, $message) = @_;
  my ($channel, $nick, $msg) = $message =~ m[^(\S+) (\S+) (.*)];
  if (my ($command) = $msg =~ m[$botInfo{prefix}($botCommands)]) {
    # we've been issued a command
    my $rval = $importedMethods{$command} -> ( $nick, $msg );
    if ($rval) { sendPub( $rval ) }
  } else { return 0 }
}


# get the bot up and running or die.
sub stage {
  $bot = MP3::Napster -> new ( "$botInfo{server}:$botInfo{port}" )
    or die "Could not connect to $botInfo{server}\n";
  $bot -> login( $botInfo{bot_name}, $botInfo{password}, 'LINK_UNKNOWN
+' )
    or die "$botInfo{bot_name} could not log in.\n";
  $bot -> join_channel( $botInfo{channel} )
    or die "$botInfo{bot_name} could not join $botInfo{channel}\n";
}

# verify that the code we are being given is good code.
sub checkFuncSyntax {
  my $codeBlock = shift;
  {
    no strict;
    local $^W = 0;
    eval "sub {\n$codeBlock\n}";
  }
  die "bad code submitted, $@\n" if $@;
  return $@ || 0;
}

#########################################################
##              object constructor, mkay?              ##
#########################################################

sub new {
  my $package = shift;
  my %attributes = %{ shift() };
  my ($bot_name, $prefix, $server, $password, $port, $channel);
  $bot_name = $attributes{name};
  $prefix = $attributes{prefix};
  $server = $attributes{server};
  $password = $attributes{password};
  $port = $attributes{port};
  $channel = $attributes{channel};
  for ($bot_name, $prefix, $server, $password, $port, $channel) {
    die "Incomplete attribute list" unless $_;
  }
  convertAttributes( \%attributes )
    or die "Attribute list malformatted";
  bless { %botInfo }, $package;
}

#########################################################
##                     methods, mkay?                  ##
#########################################################

# add a new function to the bot.
sub addFunction {
  my $self = shift;
  my ($funcName, $func) = (@_);
  if ( my $rval = checkFuncSyntax( $func ) ) {
    $importedMethods{$funcName} = $func;
    return 1;
  } else {
    warn "function $funcName not imported: $rval\n";
    return 0;
  }
}

# we do this after we're connected to get the bot running
# and install our methods.
sub botRun {
  if (! $bot ) {
    warn "Bot not connected, or bot not running...\n";
    return 0;
  }

  $bot -> callback(PUBLIC_MESSAGE, \&pubHandler);
  $bot -> callback(PRIVATE_MESSAGE, \&msgHandler);

  return 1;
}

# send a public message.
sub sendMsg {
  my $self = shift;
  my $user = shift;
  my $msg = shift;

  $self -> private_message( $user, $msg );
  return 1;
}

=cut
=pod

=head1 synposis

my $bot = Bot ->
  new( server => 'localhost', port => '8888', bot_name => 'bot',
       password => 'secret', channel = 'bots', prefix => ':' );

$bot -> stage();
$bot -> botRun();
while ($bot) {
 $bot -> addFunction( 'execute', sub { my $out = qx/shift/; $out } );
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--
Laziness, Impatience, Hubris, and Generosity.