use HTTP::Daemon;
use MIME::Base64 ();
use Getopt::Long;
use POSIX ":sys_wait_h";
use strict;

my $user_agent = 'Mozilla/5.0 (Windows; U; Windows NT 5.1; ru; rv:1.9.1b4) Gecko/20090423 Firefox/3.5b4';

my $errheader = "HTTP/1.1 200 OK\x0D\x0AContent-Type: text/plain\x0D\x0A\x0D\x0A";
my $errmsg1 = $errheader . 'Could not connect to server';
my $errmsg2 = $errheader . 'Could not connect to pproxy';

my ($pproxyhost, $pproxyport, $pproxyurl);
my ($tunnelhost, $tunnelport);
my ($pproxy, $bindport, $tunnel, $secret);
my ($destaddr, $destport, $desturl);

#Вывод справки
Usage() if @ARGV==0;

#Задание опций
GetOptions(
         "px=s"		=> \$pproxy,
         "bp=s" 	=> \$bindport,
         "tpx=s"	=> \$tunnel,
         "pwd=s"	=> \$secret
     );
die "need pproxy.php url" unless $pproxy;


#Получение параметров
$pproxy =~ /http:\/\/([\w\.\-]+)(:\d*)?\/(.+)/;
$pproxyhost = $1; $pproxyport = substr($2, 1); $pproxyurl = '/' . $3;

defined($pproxyport) || ($pproxyport = 80);
defined($bindport) || ($bindport = 8008);

if(defined($tunnel))
{
	$tunnel =~ /http:\/\/([\w\.\-]+):(\d*)?/;
	$tunnelhost = $1; $tunnelport = $2;

	$destaddr = $tunnelhost;
	$destport = $tunnelport;
	$desturl = $pproxy;

	print "# tunnelhost = $tunnelhost\n";
	print "# tunnelport = $tunnelport\n";
}else{
	$destaddr = $pproxyhost;
	$destport = $pproxyport;
	$desturl = $pproxyurl;
}

print "# pproxyhost = $pproxyhost\n";
print "# pproxyport = $pproxyport\n";
print "# pproxyurl = $pproxyurl\n";
print "# bindport = $bindport\n\n";

$|=1;
my %children;
my $slave;

#Прием подключений
my $master = HTTP::Daemon->new(	LocalPort => $bindport,
				LocalAddr => 'localhost', 
				Reuse=>1)
|| die "Can't start server ($@)";
&MainProc($slave) while $slave = $master->accept;

sub MainProc
{
		my $conn = shift;

		#Прием HTTP-запроса
		my $request = $conn->get_request();
		
		#Ответвление процесса(потока)
		my $pid = fork();
		unless(defined($pid))
		{
			print "# Erorr couldn't fork\n";
			close $conn;
			return;
		}

		if($pid)
		{
			close $conn;
			$children{$pid}++;
			foreach(keys %children )
			{
				my $kid = waitpid($_, &WNOHANG);
				delete $children{$_} if($kid == -1 || $kid == $_);
			}
			return;
		}

		#Преобразование HTTP заголовка
		$request -> remove_header('Proxy-Connection');
		$request -> remove_header('Keep-Alive');
		$request -> header(Connection=>'close');
		$request -> remove_header('User-Agent');
		$request -> header('User-Agent'=>$user_agent);
		my $host = $request -> header('Host');
		my $http = $request -> as_string();
		my $head_end = index ($http, "\x0A\x0A") + 2;
		my $head = substr ($http, 0, $head_end);
		my $post = substr ($http, $head_end);
		$head =~ s/\x0A/\x0D\x0A/g;
		$http = $head . $post;
		$http =~ s/http:\/\/$host//;
		my $time_start = time;
		
		#Отправка запроса прокси и прием результата
		SendToPProxy(	MIME::Base64::encode($host),
				MIME::Base64::encode($http),
				$conn
					);

		my $time_end = time;
		
		#Лог
		print &TranslateTimeHour($time_end), "   ", $host,
			" (", &TranslateTime($time_end - $time_start),
			")\n";

		close $conn;
		exit;
}

sub SendToPProxy
{
	my $dest_host = shift;
	my $query_content = shift;
	my $clientsock = shift;
	
	my $proxysock = IO::Socket::INET->new(Proto=>'tcp',PeerAddr=>$destaddr,PeerPort=>$destport);
	unless($proxysock)
	{
		syswrite($clientsock, $errmsg2, length($errmsg2));
		return; 
	}
	
	my $post_query;
	$post_query = 'secret=' . $secret . '&' if defined($secret);
	$post_query .= 'host=' . $dest_host . '&query=' . $query_content;
	my $postlen = length($post_query);

	my $request = "POST $desturl HTTP/1.1\x0D\x0A".
			"Host: $pproxyhost:$pproxyport\x0D\x0A".
			"Accept: */*\x0D\x0A".
			"Content-Type: application/x-www-form-urlencoded\x0D\x0A".
			"Content-Length: $postlen\x0D\x0A".
			"User-Agent: $user_agent\x0D\x0A".
			"Connection: close\x0D\x0A\x0D\x0A" . $post_query;

	syswrite($proxysock, $request, length($request));
	my ($result, $buffer, $response);
	my $contentstart = -1;
	my $count = 0;
	while(1)
	{
		$result = sysread($proxysock, $buffer, 1024);
		last if !defined($result) || !$result;

		if($contentstart == -1)
		{
			$response .= $buffer;
			last if length($response)>65535;
			$contentstart = index($response,"\x0D\x0A\x0D\x0A");
			next if $contentstart == -1;
			$buffer = substr($response, $contentstart+4);
		}
		$count += length($buffer);
		syswrite($clientsock, $buffer, length($buffer));
	}
	syswrite($clientsock, $errmsg1, length($errmsg1)) if $count == 0;
	close $proxysock;
}

sub TranslateTime
{
	my ($sec, $min, $hour, $mday, $mon, $year, $wday, $yday, $isdst) = localtime(shift);
	return sprintf "%02u:%02u", $min, $sec;
}

sub TranslateTimeHour
{
	my ($sec, $min, $hour, $mday, $mon, $year, $wday, $yday, $isdst) = localtime(shift);
	return sprintf "%02u:%02u:%02u", $hour, $min, $sec;
}

sub Usage
{
	print "Usage: $0 -px proxy_url [-bp bindport] [-tpx tunnel_proxy] [-pwd secret]\n";
	print "Example: $0 -px http://site.com/proxy/proxy.php -bp 8080\n";
	print "         $0 -px http://site.com/proxy/proxy.php -pwd pproxypass\n";
	print "         $0 -px http://site.com/proxy/proxy.php -tpx http://localhost:8118\n";
	print "\nDefault bind port - 8008\n";
	exit;
}