<?php

/*

					COPYRIGHT



Copyright 2007 Sergio Vaccaro <sergio@inservibile.org>



This file is part of JSON-RPC PHP.



JSON-RPC PHP is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation; either version 2 of the License, or

(at your option) any later version.



JSON-RPC PHP 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.  See the

GNU General Public License for more details.



You should have received a copy of the GNU General Public License

along with JSON-RPC PHP; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/



/**

 * The object of this class are generic jsonRPC 1.0 clients

 * http://json-rpc.org/wiki/specification

 *

 * @author sergio <jsonrpcphp@inservibile.org>

 */

class jsonRPCClient {

	

	/**

	 * Debug state

	 *

	 * @var boolean

	 */

	private $debug;

	

	/**

	 * The server URL

	 *

	 * @var string

	 */

	private $url;

	/**

	 * The request id

	 *

	 * @var integer

	 */

	private $id;

	/**

	 * If true, notifications are performed instead of requests

	 *

	 * @var boolean

	 */

	private $notification = false;

	

	/**

	 * Takes the connection parameters

	 *

	 * @param string $url

	 * @param boolean $debug

	 */

	public function __construct($url,$debug = false) {

		// server URL

		$this->url = $url;

		// proxy

		empty($proxy) ? $this->proxy = '' : $this->proxy = $proxy;

		// debug state

		empty($debug) ? $this->debug = false : $this->debug = true;

		// message id

		$this->id = 1;

	}

	

	/**

	 * Sets the notification state of the object. In this state, notifications are performed, instead of requests.

	 *

	 * @param boolean $notification

	 */

	public function setRPCNotification($notification) {

		empty($notification) ?

							$this->notification = false

							:

							$this->notification = true;

	}

	

	/**

	 * Performs a jsonRCP request and gets the results as an array

	 *

	 * @param string $method

	 * @param array $params

	 * @return array

	 */

	public function __call($method,$params) {

		

		// check

		if (!is_scalar($method)) {

			throw new Exception('Method name has no scalar value');

		}

		

		// check

		if (is_array($params)) {

			// no keys

			$params = array_values($params);

		} else {

			throw new Exception('Params must be given as array');

		}

		

		// sets notification or request task

		if ($this->notification) {

			$currentId = NULL;

		} else {

			$currentId = $this->id;

		}

		

		// prepares the request

		$request = array(

						'method' => $method,

						'params' => $params,

						'id' => $currentId

						);

		$request = json_encode($request);

		$this->debug && $this->debug.='***** Request *****'."\n".$request."\n".'***** End Of request *****'."\n\n";

		

		// performs the HTTP POST

		$opts = array ('http' => array (

							'method'  => 'POST',

							'header'  => 'Content-type: application/json',

							'content' => $request

							));

		$context  = stream_context_create($opts);

		if ($fp = fopen($this->url, 'r', false, $context)) {

			$response = '';

			while($row = fgets($fp)) {

				$response.= trim($row)."\n";

			}

			$this->debug && $this->debug.='***** Server response *****'."\n".$response.'***** End of server response *****'."\n";

			$response = json_decode($response,true);

		} else {

			throw new Exception('Unable to connect to '.$this->url);

		}

		

		// debug output

		if ($this->debug) {

			echo nl2br($debug);

		}

		

		// final checks and return

		if (!$this->notification) {

			// check

			if ($response['id'] != $currentId) {

				throw new Exception('Incorrect response id (request id: '.$currentId.', response id: '.$response['id'].')');

			}

			if (!is_null($response['error'])) {

				throw new Exception('Request error: '.$response['error']);

			}

			

			return $response['result'];

			

		} else {

			return true;

		}

	}

}

?>