#!/usr/bin/env perl
#
# Copyright (c) 2022 Mischa Peters <mischa @ high5.nl>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
use 5.024;
use strict;
use warnings;
use autodie;
use Getopt::Std;
use DBI;

my $db_type = 'MariaDB';
my $db_host = '';
my $db_user = '';
my $db_pass = '';
my $db_name = '';

getopts('dv');
our($opt_d, $opt_v);

my $email = "";
my $from = "";
my %ooo;
my $dbh = DBI->connect("DBI:$db_type:$db_name:$db_host", "$db_user", "$db_pass", {RaiseError => 1});
sub do_query {
	my ($query) = @_;
	my $sth = $dbh->prepare($query);
	$sth->execute;
	return $sth;
}

open (my $fh, '>', "/tmp/virtualvacation.log") if ($opt_d);
select(STDOUT);
$|++;
select($fh);
$|++;
print STDOUT "register|filter|smtp-in|rcpt-to\n";
print STDOUT "register|filter|smtp-in|mail-from\n";
print STDOUT "register|filter|smtp-in|data-line\n";
print STDOUT "register|ready\n";

while (my $line = <>) {
	next if ($line =~ m/^config/);
	chomp $line;
	print $fh "$line\n" if ($opt_v);
	if ($line =~ m/filter/) {
		my ($stream, $version, $timestamp, $subsystem, $event, $sid, $token, $data) = split /\|/, $line;
		if ($line =~ m/mail-from/) {
			$from = $data;
			print STDOUT "filter-result|$sid|$token|proceed\n";
		}
		if ($line =~ m/rcpt-to/) {
			$email = $data;
			$ooo{$sid} = 1;
			print $fh "Virtual Vacation: created session $sid\n";
			print STDOUT "filter-result|$sid|$token|proceed\n";
		}
		if ($line =~ m/data-line/) {
			if (!$data) { $data = ""; }
			if ($data =~ m/^precedence:\s+(bulk|list|junk)/i) { $ooo{$sid} = 0; }
			if ($data =~ m/^x-loop:\s+opensmtpd\ admin\ virtual\ vacation/i) { $ooo{$sid} = 0; }
			print STDOUT "filter-dataline|$sid|$token|$data\n";
		}
		if ($line =~ m/data-line/ && $data eq '.' && $ooo{$sid} == 1) {
			print $fh "Virtual Vacation: To: $email, From: $from\n" if ($opt_d);
			my $query = qq{SELECT subject,body FROM vacation WHERE email='$email' and active=1};
			my $sth = do_query($query);
			my $rv = $sth->rows;
			if ($rv == 1) {
				my @row = $sth->fetchrow_array;
				print $fh "Virtual Vacation: Found OOO for $email\n" if ($opt_d);
				$query = qq{SELECT cache FROM vacation WHERE email='$email' AND FIND_IN_SET('$from',cache)};
				$sth = do_query ($query);
				$rv = $sth->rows;
				if ($rv == 0) {
					$query = qq{UPDATE vacation SET cache=CONCAT(cache,',','$from') WHERE email='$email'};
					$sth = do_query($query);
					print $fh "Virtual Vacation: Sending OOO to $from\n" if ($opt_d);
					open my $fh_email, "|-", "/usr/sbin/sendmail -t";
					print $fh_email "From: $email\n";
					print $fh_email "To: $from\n";;
					print $fh_email "Subject: $row[0]\n";
					print $fh_email "X-Loop: OpenSMTPD Admin Virtual Vacation\n";
					print $fh_email "Content-Type: text/plain; charset=utf-8\n\n";
					print $fh_email "$row[1]\n";
					close $fh_email;
				}
			delete $ooo{$sid};
			print $fh "Virtual Vacation: removed session $sid\n" if ($opt_d);
			}
		} elsif ($line =~ m/data-line/ && $data eq '.' && $ooo{$sid} == 0) {
			delete $ooo{$sid};
			print $fh "Virtual Vacation: removed session $sid\n" if ($opt_d);
		}
	}
}
close $fh;
0;