Irssi script that shows a list of nicks affected by a ban once it's set or unset

ban-affects.pl

use Irssi;
use strict;
use vars qw($VERSION %IRSSI);

$VERSION = "0.3";
%IRSSI = (
    authors => "wodim",
    contact => '[email protected]',
    name => "ban-affects",
    description => "Shows a list of nicks affected by a ban once it's set or unset",
    license => "BSD",
    url => "",
);

sub ban_new {
    my ($channel, $ban) = @_;

    # return if the channel is not synchronised yet
    # (we know no user masks yet)
    return unless $channel->{wholist};

    my @affected_nicks;
    foreach my $nick ($channel->nicks()) {
        if ($channel->{server}->mask_match_address(
                $ban->{ban}, $nick->{nick}, $nick->{host})) {
            if ($channel->{server}->{nick} eq $nick->{nick}) {
                push @affected_nicks, $nick->{nick} . " (YOU!)";
            } else {
                push @affected_nicks, $nick->{nick};
            }
        }
    }

    if (scalar @affected_nicks) {
        $channel->printformat(MSGLEVEL_CLIENTNOTICE, "ban_affects",
            $ban->{ban}, $ban->{setby}, join(", ", @affected_nicks));
    }
}

sub ban_remove {
    my ($channel, $ban) = @_;

    # return if the channel is not synchronised yet
    # (we know no user masks yet)
    return unless $channel->{wholist};

    my @affected_nicks;
    foreach my $nick ($channel->nicks()) {
        if ($channel->{server}->mask_match_address(
                $ban->{ban}, $nick->{nick}, $nick->{host})) {
            if ($channel->{server}->{nick} eq $nick->{nick}) {
                push @affected_nicks, $nick->{nick} . " (YOU!)";
            } else {
                push @affected_nicks, $nick->{nick};
            }
        }
    }

    if (scalar @affected_nicks) {
        $channel->printformat(MSGLEVEL_CLIENTNOTICE, "unban_affects",
            $ban->{ban}, $ban->{setby}, join(", ", @affected_nicks));
    }
}

Irssi::theme_register([
    "ban_affects", 'Ban {ban $0} set by {nick $1} affects: {hilight $2}',
    "unban_affects", 'Ban {ban $0} set by {nick $1} was affecting: {hilight $2}',
]);

Irssi::signal_add_last("ban new", "ban_new");
Irssi::signal_add_last("ban remove", "ban_remove");