# automode.pl
# Matt Sparks, http://f0rked.com
# 
# Passively learn and actively maintain the ops/voices/halfops in channels.
# This is no-maintenance auto-op/auto-voice script for irssi.
# 
# INSTALL:
#   1) /script load automode.pl
#   2) Be a channel operator
#
# HOW IT WORKS:
#   When someone joins a channel and is given ops/voice/halfop, the script
#   will record that user's mask, as a combination of their nickname and part
#   of their hostname or IP address. When that person leaves and rejoins, the 
#   script will check against its database and regrant the user the modes 
#   he or she had before leaving.
#
#   If a user is kicked from a channel, all modes for that person are removed.
#   They must therefore be regiven by another operator manually. Note this.
#
#   Also, this script relies on the "chatnet" attribute being set for a
#   particular connection. Use /network (or /ircnet) to set up your networks
#   and such. This script will spit out (lots of) warnings if the chatnet is 
#   not set.
#
# IGNORING CHANNELS:
#   If you do not wish to maintain modes on a channel, add it to the setting
#   "automode_ignore" in the form <tag>:<channel>, separated by spaces.
#  
#   For example: /set automode_ignore FreeNode:#perl EFnet:#irssi
#                (should) not maintain modes in #perl on FreeNode or #irssi
#                on EFnet, provided FreeNode and EFnet are the tags for those
#                connections.
#
# NOTES:
#   The Perl module Data::Serializer is needed for this script.
#   The database file is not written instantaneously; it is on a timer and is
#   written to every five minutes or so. If the script is reloaded before it has
#   had a chance to save will result in forgotten modes.
#
use strict;
use Irssi;
use Data::Serializer;
use Data::Dumper;

use vars qw($VERSION %IRSSI);

$VERSION = '1.2';
%IRSSI = (
    authors     => 'Matt "f0rked" Sparks',
    contact     => 'root@f0rked.com',
    name        => 'automode',
    description => 'Mode maintainer',
    license     => 'GPLv2',
    url         => 'http://f0rked.com',
    changed     => '2006-10-21',
);

# show debug lines
my $debug = 0;

my $s=new Data::Serializer;
my $file=Irssi::get_irssi_dir."/automode_list";

if (!-e $file) {
    print "[automode] creating $file";
    system("touch $file");
}

my $listref=$s->retrieve($file);
my %list = $listref ? %{$listref} : ();

#print Dumper %list;

my $save_tag;
my %buffer_tags;
my %buffer;

sub save_list {
    $s->store(\%list,$file);
}

sub clear_list {
    %list = ();
}

sub make_mask {
    my($address)=@_;
    return if !$address;
    my($ident,$host)=split /@/,$address;
    my @split=split /\./,$host;
    if (@split <= 2) {
        # host is something like "f0rked.com". We cannot make the mask *.com.
    }
    else {
        if ($split[$#split] =~ /^\d+$/) {
            # Looks like an IP address.
            pop @split;
            $host=join(".",@split).".\d{1,3}";
        }
        else {
            # Mask the first segment.
            shift @split;
            $host=".+?.".join(".",@split);
        }
    }
    return ".+?!.*${ident}@"."${host}";
}

sub show {
    my($net,$channel)=@_;
    print Dumper %{$list{$net}->{$channel}};
}

sub show_all {
    my $list;
    print Dumper %list;
}

sub set_modes {
    my($net,$channel)=@{$_[0]};
    return if !$buffer{$net}->{$channel};
    my($nicks,$modes)=values(%{$buffer{$net}->{$channel}});
    print "[automode] modes: $modes, nicks: $nicks" if $debug;
    my $c=Irssi::server_find_chatnet($net)->channel_find($channel);
    
    # iterate through the modes and see which ones we don't have to set
    my($final_modes, $final_nicks);

    my $i=0;
    for(split //,$modes) {
        my $m = $_;
        my $n = (split / /,$nicks)[$i];
        $i++;

        next if (!$c->nick_find($n));
        next if ($m eq "o" && $c->nick_find($n)->{"op"});
        next if ($m eq "v" && $c->nick_find($n)->{"voice"});
        next if ($m eq "h" && $c->nick_find($n)->{"halfop"});
        
        # if we made it this far, add this to the final modes
        $final_modes .= $m;
        $final_nicks .= "$n ";
    }
    print "[automode] final modes: +$final_modes $final_nicks" if $debug;

    $c->command("MODE $channel +$final_modes $final_nicks")
        if ($final_modes && $final_nicks);
    delete($buffer{$net}->{$channel});
}

sub mode2letter {
    my($mode)=@_;
    if ($mode eq "@") {
        return "o";
    } elsif ($mode eq "+") {
        return "v";
    } elsif ($mode eq "%") {
        return "h";
    }
    return -1;
}

sub remove_mode {
    my($net,$channel,$mask,$mode)=@_;
    my $letter=mode2letter($mode);
    $list{$net}->{$channel}->{$mask} =~ s/$letter//
        if user_modes($net,$channel,$mask);
    delete($list{$net}->{$channel}->{$mask})
    if exists $list{$net}->{$channel}->{$mask}
        and !$list{$net}->{$channel}->{$mask};
}

sub remove_all {
    my($net,$channel,$mask)=@_;
    delete($list{$net}->{$channel}->{$mask})
        if exists $list{$net}->{$channel}->{$mask};
}

sub user_modes {
    my($net,$channel,$mask)=@_;
    return $list{$net}->{$channel}->{$mask};
}

sub add_mode {
    my($net,$channel,$mask,$mode)=@_;
    return if !$mask or !$net or !$channel or !$mode;
    my $letter=mode2letter($mode);
    $list{$net}->{$channel}->{$mask}.=$letter 
        if $list{$net}->{$channel}->{$mask} !~ /$letter/;
    Irssi::timeout_remove($save_tag);
    $save_tag=Irssi::timeout_add_once(300,"save_list",[]);
}

sub event_mode {
    my($channel,$nick,$setby,$mode,$type)=@_;
    return if check_ignore($channel->{server},$channel->{name});
    my $w=Irssi::active_win;
    return if $mode != '@' and $mode != '%' and $mode != '+';
    my $chatnet=$channel->{server}->{chatnet};
    my $tag=$channel->{server}->{tag};
    print "[automode] The 'chatnet' attribute is missing for the tag '$tag'. Use /network (or /ircnet) to properly manage this."
        if !$chatnet;
    return if !$chatnet;
    
    my $mask=make_mask($nick->{host});
    print "[automode] failed to make mask ($mask)" if (!$mask && $debug);
    return if !$mask;
    
    if ($type eq "+") {
        print "[automode] adding mode '$mode' for $mask in $channel->{name} on $chatnet"
            if $debug;
        add_mode($chatnet,$channel->{name},$mask,$mode);
    }
    else {
        return if $setby eq $nick->{nick}; # don't remove op if they deop themselves.
        print "[automode] removing mode '$mode' for $mask in $channel->{name} on $chatnet"
            if $debug;
        remove_mode($chatnet,$channel->{name},$mask,$mode);
    }
    #show($chatnet,$channel->{name});
}

sub event_join {
    my($server,$channel,$nick,$address)=@_;
    return if check_ignore($server,$channel);
    my $mask=make_mask($address);
    return if !user_modes($server->{chatnet},$channel,$mask);
    my $c=$server->channel_find($channel);
    return if not $c->{chanop};

    if (my $modes=user_modes($server->{chatnet},$channel,$mask)) {
        print "[automode] Matched mask ($mask) with modes: $modes" if $debug;
        my $nick_list="$nick "x length($modes); 
        my %buf = $buffer{$server->{chatnet}}->{$channel} ?
            %{$buffer{$server->{chatnet}}->{$channel}} :
            ();
        $buf{modes}.=$modes;
        $buf{nicks}.=$nick_list;
        $buffer{$server->{chatnet}}->{$channel}=\%buf;
        my $tag=$server->{chatnet}."_$channel";
        Irssi::timeout_remove($buffer_tags{$tag});
        $buffer_tags{$tag}=Irssi::timeout_add_once(1000+int(rand(250)*3),
                                                   "set_modes",
                                                   [$server->{chatnet},$channel]);
        #print Dumper %buffer;
    }
}

sub event_kick {
    my($server,$channel,$nick,$kicker,$address,$reason)=@_;
    my $n=$server->channel_find($channel)->nick_find($nick);
    #print Dumper $n;
    my $mask=make_mask($n->{host});
    remove_all($server->{chatnet},$channel,$mask) if $mask;
}

sub check_ignore {
    my($server,$channel)=@_;
    my $chatnet=$server->{chatnet};
    my $ignore=Irssi::settings_get_str("automode_ignore")." ";
    return ($ignore =~ /$chatnet:$channel /i) ? 1 : 0;
}

# I don't think this does what I want it to do.
sub event_exit {
    save_list;
}

Irssi::signal_add("gui exit","event_exit");

Irssi::signal_add("message kick","event_kick");
Irssi::signal_add("message join","event_join");
Irssi::signal_add("nick mode changed","event_mode");

Irssi::settings_add_str("misc","automode_ignore","IM:&bitlbee");