#!/usr/bin/perl
package Karma;

use strict;
use warnings;

use Data::Dumper;
use Net::IP qw(:PROC);
use POSIX qw(strftime);

use lib 'lib';
use Qpsmtpd::Base;
use Qpsmtpd::DB;

my $base = Qpsmtpd::Base->new();
my $self = bless({args => {db_dir => 'config'},}, 'Karma');
my $command = $ARGV[0];

if (!$command) {
    $self->usage();
}
elsif ($command eq 'capture') {
    $self->capture($ARGV[1]);
}
elsif ($command eq 'release') {
    $self->release($ARGV[1]);
}
elsif ($command eq 'prune') {
    $self->prune_db($ARGV[1] || 7);
}
elsif ($command eq 'search' && is_ip($ARGV[1])) {
    $self->show_ip($ARGV[1]);
}
elsif ($command eq 'list' | $command eq 'search') {
    $self->main();
}

exit(0);

sub usage {
    print <<EO_HELP
 karma_tool [ list search prune capture release ]

list takes no arguments.

search [ naughty nice both <ip> ]
  and returns a list of matching IPs

capture [ IP ]
  sends an IP to the penalty box

release [ IP ]
  remove an IP from the penalty box

prune takes no arguments.
  prunes database of entries older than 7 days

EO_HELP
      ;
}

sub db {
    my ( $self ) = @_;
    return $self->{db} if $self->{db};
    $self->{db} = Qpsmtpd::DB->new( name => 'karma' );
    $self->{db}->candidate_dirs(
        $self->{args}{db_dir},
        qw( /var/lib/qpsmtpd/karma ./var/db ./config . ) );
    my $path = $self->{db}->path;
    print "using karma db at $path\n";
    return $self->{db};
}

sub capture {
    my $self = shift;
    my $ip = shift or return;
    is_ip($ip) or do {
        warn "not an IP: $ip\n";
        return;
    };

    $self->db->lock;
    my $key  = $self->get_karma_key($ip);

    my ($penalty_start_ts, $naughty, $nice, $connects) = split /:/,
      $self->db->get( $key );

    $self->db->set( $key, join(':', time, $naughty + 1, $nice, $connects) );
    $self->db->unlock;
}

sub release {
    my $self = shift;
    my $ip = shift or return;
    is_ip($ip) or do { warn "not an IP: $ip\n"; return; };

    $self->db->lock;
    my $key  = $self->get_karma_key($ip);

    my ($penalty_start_ts, $naughty, $nice, $connects) = split /:/,
      $self->db->get( $key );

    $self->db->set( $key, join(':', 0, 0, $nice, $connects) );
    $self->db->unlock;
}

sub show_ip {
    my $self = shift;
    my $ip   = shift or return;
    $self->db->lock;

    my $key  = $self->get_karma_key($ip);

    my ($penalty_start_ts, $naughty, $nice, $connects) = split /:/,
      $self->db->get( $key );
    $self->db->unlock;
    $naughty  ||= 0;
    $nice     ||= 0;
    $connects ||= 0;
    my $time_human = '';
    if ($penalty_start_ts) {
        $time_human = strftime "%a %b %e %H:%M", localtime $penalty_start_ts;
    }
    my $hostname = $base->resolve_ptr($ip);
    print
"      IP Address                 Penalty        Naughty  Nice  Connects  Hostname\n";
    printf(" %-18s  %24s    %3s     %3s     %3s    %-30s\n",
           $ip, $time_human, $naughty, $nice, $connects, $hostname);
}

sub main {
    my $self = shift;

    $self->db->lock;
    my %totals;

    print
"      IP Address                 Penalty        Naughty  Nice  Connects  Hostname\n";
    foreach my $r ( $self->db->get_keys ) {
        my $ip = ip_bintoip(ip_inttobin($r, 4), 4);
        my ($penalty_start_ts, $naughty, $nice, $connects) = split /:/,
          $self->db->get( $r );
        $naughty  ||= '';
        $nice     ||= '';
        $connects ||= '';
        my $time_human = '';
        if ($command eq 'search') {
            my $search = $ARGV[1];
            if ($search eq 'nice') {
                next if !$nice;
            }
            elsif ($search eq 'naughty') {
                next if !$naughty;
            }
            elsif ($search eq 'both') {
                next if !$naughty || !$nice;
            }
            elsif (is_ip($ARGV[1]) && $search ne $ip) {
                next;
            }
        }
        if ($penalty_start_ts) {
            $time_human = strftime "%a %b %e %H:%M",
              localtime $penalty_start_ts;
        }
        my $hostname = '';
        if ($naughty && $nice) {
            # this can be slow, waiting for each IP to resolve
            #$hostname = $base->resolve_ptr($ip);
        }
        printf(" %-18s  %24s    %3s     %3s     %3s    %30s\n",
               $ip, $time_human, $naughty, $nice, $connects, $hostname);
        $totals{naughty}  += $naughty  if $naughty;
        $totals{nice}     += $nice     if $nice;
        $totals{connects} += $connects if $connects;
    }
    $self->db->unlock;
    print Dumper(\%totals);
}

sub is_ip {
    my $ip = shift || $ARGV[0];
    new Net::IP($ip) or return;
    return 1;
}

sub get_karma_key {
    my $self = shift;
    my $nip = Net::IP->new(shift) or return;
    return $nip->intip;    # convert IP to an int
}

sub prune_db {
    my $self       = shift;
    my $prune_days = shift;

    $self->db->lock;
    my $count = $self->db->size;

    my $pruned = 0;
    foreach my $key ( $self->db->get_keys ) {
        my ($ts, $naughty, $nice, $connects) = split /:/, $self->db->get( $key );
        my $days_old = (time - $ts) / 86400;
        next if $days_old < $prune_days;
        $self->db->delete( $key );
        $pruned++;
    }
    $self->db->unlock;
    warn "pruned $pruned of $count DB entries";
}