<?php

$connections = array();
$first = -1;

require('udp-inc.php');

error_reporting(E_ALL | E_STRICT);

out(__FILE__, __LINE__, 'Opening server port...');
$socket = stream_socket_server('udp://0.0.0.0:9060', $errno, $errstr, STREAM_SERVER_BIND);

if ((!is_resource($socket)) || ($errno > 0)) {
	out(__FILE__, __LINE__, $errstr . ' (' . $errno . ')');
	exit;
}

if (!stream_set_blocking($socket, FALSE)) {
	out(__FILE__, __LINE__, 'ERROR: Cannot set non-blocking mode!');
	exit;
}

$pkt = '';

out(__FILE__, __LINE__, 'Waiting for connections...');

do {
	$pkt = trim(stream_socket_recvfrom($socket, 1500, 0, $peer));

	if ($pkt == 'PING') {
		// Peer in list?
		if (!isset($connections[$peer])) {
			out(__FILE__, __LINE__, 'New peer ' . $peer . ' detected.');
			$connections[$peer] = 1;
		} elseif ($connections[$peer] == 0) {
			out(__FILE__, __LINE__, 'Peer ' . $peer . ' has returned.');
			$connections[$peer] = 1;
		}

		//out(__FILE__, __LINE__, 'Sending data to peer ' . $peer . '.');
		stream_socket_sendto($socket, (time() . ':md5=' . md5(time())), 0, $peer);
	} elseif ($pkt == 'BYE') {
		// Peer in list?
		if (!isset($connections[$peer])) {
			out(__FILE__, __LINE__, 'Peer ' . $peer . ' is NOT in peer list.');
		} else {
			out(__FILE__, __LINE__, 'Peer ' . $peer . ' is leaving us.');
			stream_socket_sendto($socket, 'BYE', 0, $peer);
			$connections[$peer] = 0;
		}
	} elseif (!empty($peer)) {
		out(__FILE__, __LINE__, 'Invalid packet ' . $pkt . ' from peer ' . $peer . '.');
		stream_socket_sendto($socket, 'INVALID', 0, $peer);
	} else {
		// Waiting for packages
		$pkt = '';
	}

	$test = (round(date('s', time()) / 10));
	if ($first != $test) {
		out(__FILE__, __LINE__, count($connections) . ' total connections so far.', true);
		$first = $test;
	}

	// Sleep a little
	if (function_exists('time_nanosleep')) time_nanosleep(0, 500000);
} while ($pkt !== FALSE);

?>