<?php
/*!
 * \file starmade_query.inc.php
 * \brief Allows a single call to fetch the server listing data for the specified starmade server.
 * \ingroup TwoSphere
 **/

/*
 * This program is free software; you can redistribute it and/or modify
 * it in any way you see fit. Just give me credit where it's apropriate.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Comments are setup for use with DOXYGEN.
 *
 */


/**
 * \addtogroup TwoSphere
 * @{*/
	namespace TwoSphere\Starmade;


/**
 * ##Starmade server connection manager
 *
 * \author	Stefan Kent
 * \email 	skent@twosphere.com.au
 * \date	10/2013
 * \version 1.0
 *
 **/
	class server
	{
		private $port;
		private $host;
		private $address;
		private $request;
		public $raw;

		public $version;
		public $connected;
		public $capacity;
		public $name;
		public $description;

	/**
	 * \brief Constructor
	 *
	 * Resolves the hostname, and loads the query packet
	 * ready for the query call.
	 *
	 * \param string $host The hostname or IP address of the server to connect to.
	 * \param string $port Specify the port if it is non-standard.
	 * \return Null
	 */
		public function __construct($host,$port = 4242)
		{
			//Set up the environment.
			$this->request = chr(0x00).chr(0x00).chr(0x00).chr(0x09).chr(0x2a).chr(0xff).chr(0xff).chr(0x01).chr(0x6f).chr(0x00).chr(0x00).chr(0x00).chr(0x00);
			$this->address = gethostbyname($host);
			$this->port = $port;
			$this->host = $host;
		}


	/**
	 * \brief Query the server
	 *
	 * Connects to the server, waits for response,
	 * creates a packet object
	 * and translates the information into it's respective variables.
	 *
	 * \return Null
	 */
		public function query()
		{
			$socket = socket_create ( AF_INET , SOCK_STREAM , SOL_TCP );
			if(@socket_connect($socket,$this->address,$this->port))
			{
				if(!@socket_send($socket,$this->request,strlen($this->request),MSG_EOF))
				{
					//There was a problem sending the request.
					throw new \Exception("Failed to send query; reason: " . socket_strerror(socket_last_error($socket)));
				}

				if (false !== ($bytes = @socket_recv($socket, $buf, 2048, MSG_WAITALL)))
				{
					//Success
				}
				else
				{
					//There was a problem with the server response.
					throw new \Exception("Failed to recieve response; reason: " . socket_strerror(socket_last_error($socket)));
				}
				socket_close($socket);

				//Interpret translate the stream into an array.
				$this->raw = new server_packet($buf);
			}
			else
			{
				//Couldn't connect to the server at all.
				throw new \Exception("Could not connect to server at:".$this->address." (".$this->host.")");
			}

			//Process the packet.
			$this->version 		= $this->raw->data[3]['value'];
			$this->name 		= $this->raw->data[4]['value'];
			$this->description 	= $this->raw->data[5]['value'];
			$this->connected 	= $this->raw->data[7]['value'];
			$this->capacity 	= $this->raw->data[8]['value'];
		}
	}


/**
 * ##Packet interpreter for starmade server.
 *
 *
 * \author	Stefan Kent
 * \email 	skent@twosphere.com.au
 * \date	10/2013
 * \version 1.0
 *
 **/
	class server_packet
	{
		public $data;	/**< The resulting array after conversion. */

	/**
	 * \brief Constructor
	 *
	 * This will take the stream and break it
	 * into an array based on the datatype
	 * in the order that it was recieved.
	 *
	 * \param string $buf Raw response from the server.
	 * \return Null
	 */
		public function __construct($buf)
		{
			$pointer = 6;
			while($pointer < strlen($buf))
			{
				$mark = ord(substr($buf,$pointer,1));
				$pointer++;

				switch($mark)
				{
					case 1: //int
						list(,$unpacked) = unpack("N", substr($buf,$pointer,4));
						if($unpacked >= pow(2, 31)) $unpacked -= pow(2, 32);
						$pointer+=4;
						$this->data[] = array("type"=>"int","value"=>$unpacked);

					break;

					case 3: //float
						list(,$value) = (pack('d', 1) == "\77\360\0\0\0\0\0\0")?unpack('f', substr($buf,$pointer,4)):unpack('f', strrev(substr($buf,$pointer,4)));
						$pointer+=4;
						$this->data[] = array("type"=>"float","value"=>$value);

					break;

					case 4: //string

						list(,$unpacked) = unpack("n", substr($buf,$pointer,2));
						if($unpacked >= pow(2, 15)) $unpacked -= pow(2, 16); // Convert unsigned short to signed short.
						$strlen = $unpacked;
						$pointer+=2;

						$this->data[] = array("type"=>"string","value"=>substr($buf,$pointer,$strlen));
						$pointer+=$strlen;

					break;

					case 6: //Byte
						$this->data[] = array("type"=>"byte","value"=>ord(substr($buf,$pointer,1)));
						$pointer++;

					break;

					case 0: //null
					default:
					break;
				}
			}
		}

	}
/**@}*/
?>