#!/usr/bin/perl

use warnings;
use strict;
use Bencode qw(bencode bdecode);
use Getopt::Long;
use Socket;
use Socket6;
use Data::Dumper;

my %options = ('proxy-address' => 'localhost', 'proxy-port' => 2223);

GetOptions(
	'proxy-address=s'		=> \$options{'proxy-address'},
	'proxy-port=s'			=> \$options{'proxy-port'},
	'from-tag=s'			=> \$options{'from-tag'},
	'to-tag=s'			=> \$options{'to-tag'},
	'call-id=s'			=> \$options{'call-id'},
	'protocol=s'			=> \$options{'transport protocol'},
	'trust-address'			=> \$options{'trust address'},
	'symmetric'			=> \$options{'symmetric'},
	'asymmetric'			=> \$options{'asymmetric'},
	'replace-origin'		=> \$options{'replace-origin'},
	'replace-session-connection'	=> \$options{'replace-session connection'},
	'client-address=s'		=> \$options{'client-address'},
	'sdp=s'				=> \$options{'sdp'},
	'sdp-file=s'			=> \$options{'sdp-file'},
	'ICE=s'				=> \$options{'ICE'},
	'force'				=> \$options{'force'},
	'v|verbose'			=> \$options{'verbose'},
) or die;

my $cmd = shift(@ARGV) or die;

my %packet = (command => $cmd);

for my $x (split(',', 'from-tag,to-tag,call-id,transport protocol,media address,ICE')) {
	defined($options{$x}) and $packet{$x} = $options{$x};
}
for my $x (split(',', 'trust address,symmetric,asymmetric,force')) {
	defined($options{$x}) and push(@{$packet{flags}}, $x);
}
for my $x (split(',', 'origin,session connection')) {
	defined($options{'replace-' . $x}) and push(@{$packet{replace}}, $x);
}

if (defined($options{sdp})) {
	$packet{sdp} = $options{sdp};
}
elsif (defined($options{'sdp-file'})) {
	open(F, '<', $options{'sdp-file'}) or die $!;
	my @sdp = <F> or die $!;
	close(F);
	$packet{sdp} = join('', @sdp);
}
elsif (@ARGV && $ARGV[0] eq 'sdp') {
	shift(@ARGV);
	$options{'client-address'} or die;
	my ($ca, $cp);
	if ($ca = inet_pton(AF_INET, $options{'client-address'})) {
		$ca = inet_ntop(AF_INET, $ca);
		$cp = "IP4";
	}
	elsif ($ca = inet_pton(AF_INET6, $options{'client-address'})) {
		$ca = inet_ntop(AF_INET6, $ca);
		$cp = "IP6";
	}
	$ca or die;
	my $sdp = "v=0\r\no=- 12345 67890 IN $cp $ca\r\ns=session\r\nc=IN $cp $ca\r\nt=0 0\r\n";

	$packet{sdp} = $sdp;
}

$options{verbose} and print Dumper \%packet;

my $cookie = rand() . ' ';
my $packet = $cookie . bencode(\%packet);

socket(S, AF_INET, SOCK_DGRAM, 0) or die $!;
send(S, $packet, 0, pack_sockaddr_in($options{'proxy-port'}, inet_aton($options{'proxy-address'}))) or die $!;
my $ret;
recv(S, $ret, 0x10000, 0);
$ret =~ s/^\Q$cookie\E//s or die $ret;
my $resp = bdecode($ret, 1);

#print Dumper $resp;
#exit;

exists($$resp{result}) or die Dumper $resp;
print("Result: \"$$resp{result}\"\n");
if ($$resp{result} eq 'error') {
	print("Error reason: \"$$resp{'error-reason'}\"\n");
	exit(1);
}
if (defined($$resp{sdp})) {
	print("New SDP:\n-----8<-----8<-----8<-----8<-----8<-----\n$$resp{sdp}\n".
		"----->8----->8----->8----->8----->8-----\n");
}