example.php

require_once 'wopr.php';

$settings = array(
	'host'	=> 'localhost',
	'port'	=> 1981,
);


$wopr = new WOPR($settings['host'], $settings['port']);
$wopr->connect();

$wopr->getIndex(); // Get a new Index for WOPR.

$wopr->send('WRD', 'hallo');
$result = $wopr->send('GEN');

print_r($result);

wopr.php

<?php

class WOPR_Exception  		extends Exception {};
class WOPR_TimeoutException		extends WOPR_Exception {};
class WOPR_OverloadException	extends WOPR_Exception {};

class WOPR {
	var $host	= null;
	var $port	= null;
	var $index	= null;
	var $socket	= null;
	
	function __construct($host, $port) {
		$this->host = $host;
		$this->port = $port;
	}
	
	function connect() {
		if( $this->socket === null ) {
			$hostip = gethostbyname($this->host);
			$this->socket = fsockopen($hostip, $this->port, $errno, $errstr, 30);
			stream_set_timeout($this->socket, 100);
		}
	}
	
	function disconnect() {
		fclose( $this->socket );
		$this->socket = null;
	}	
	
	function setIndex($index) {
		$this->index = $index;
	}
	
	function getIndex() {
		$response = $this->send('START');
		
		$pdt_idx = $response['pdt_idx'];
		if( $pdt_idx === -1 ) {
			throw new WOPR_OverloadException("No available slots");
		}
		$this->index = $pdt_idx;
		return $pdt_idx;
	}
	
	function getSpecs($command) {
		$commands = array(
			'INFO'	=> array('args' => false,				'index' => false),
			'START'	=> array('args' => false,				'index' => false),
			'DEL'	=> array('args' => false,				'index' => true),
			'FEED'	=> array('args' => '/^[^\\n]+$/',		'index' => true),
			'LTR'	=> array('args' => '/^[^\\n\\s]$/',		'index' => true),
			'WRD'	=> array('args' => '/^[^\\n\\s]+$/',	'index' => true),
			'CTX'	=> array('args' => false,				'index' => true),
			'GEN'	=> array('args' => false,				'index' => true),
			'CLR'	=> array('args' => false,				'index' => true)
		);
		if( !array_key_exists($command, $commands) ) {
			return null;
		} else {
			return $commands[$command];
		}
	}
	
	function validate($command, $index, $arguments = "") {
		$specs = $this->getSpecs($command);
		
		if( $specs === null ) {
			throw new WOPR_Exception("Unknown command: " . json_encode($command));
		}
		
		if( $specs['args'] === false ) {
			if( $arguments !== null && $arguments !== "" ) {
				throw new WOPR_Exception("Command {$command} doesn't take any arguments.");
			}
		} else {
			$match = preg_match($specs['args'], $arguments);
			if( !$match ) {
				throw new WOPR_Exception("Invalid arguments for command {$command}");
			}
		}
		
		if( $specs['index'] && !is_numeric($index) ) {
			throw new WOPR_Exception("Command {$command} requires index");
		}
		return true;
	}
	
	function buildCommandString($command, $index = null, $arguments = "") {
		$this->validate($command, $index, $arguments);
		$specs = $this->getSpecs($command);
		
		$cmdstring = $command;
		if( $specs['index'] ) {
			$cmdstring .= " {$index}";
		}
		if( $specs['args'] !== false ) {
			$cmdstring .= " {$arguments}";
		}
		$cmdstring .= "\n";
		return $cmdstring;
	}

	// Send a command to WOPR.
	// Returns WOPR response as a PHP-array.
	function send($command, $arguments = "") {
		$this->connect();
		$cmdstring = $this->buildCommandString($command, $this->index, $arguments);
		fwrite($this->socket, $cmdstring);
		$response = $this->read($command);
		
		$this->disconnect();
		return $response;
	}
	
	function read($command) {
		if ( ! feof($this->socket) ) {
			$response	= fgets( $this->socket );
			$info		= stream_get_meta_data($this->socket);
			if ($info['timed_out']) {
				throw new WOPR_TimeoutException();
			}
			if( strlen($response) > 0 ) {
				return $this->parseResponse($response, $command);
			} else {
				return null;
			}
		}
	}
	
	function parseResponse($string, $command) {
		$xml = new SimpleXMLElement($string);
		$array = (array)$xml;
		if( isset($array[0]) && $array[0] == 'error' ) {
			throw new WOPR_Exception("Unknown WOPR error");
		}
		return $array;
	}
}