<?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
 */
if (! isset($base_path)) {
    $base_path = '.';
}

require_once $base_path . "/classes/encoding_normalize.class.php";

/**
 * The object of this class are generic jsonRPC 1.0 clients
 * http://json-rpc.org/wiki/specification
 *
 * @author sergio <jsonrpcphp@inservibile.org>
 * @author emartin <emartin@sigb.net>
 */
class pmb_jsonrpc_client
{

    /**
     * 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;

    /**
     * Authentication Type.
     * Valid values: none, json, http
     *
     * @var string
     */
    private $authentication_type = 'none';

    /**
     * Authentification User.
     * Only used when authentication_type != 'none'
     *
     * @var string
     */
    private $authentication_user = '';

    /**
     * Authentification Password.
     * Only used when authentication_type != 'none'
     *
     * @var string
     */
    private $authentication_password = '';

    /**
     * Timeout allowed for http request
     *
     * @var int
     */
    private $timeout = 0;

    /**
     * Takes the connection parameters
     *
     * @param string $url
     * @param boolean $debug
     */
    public function __construct($url, $debug = false)
    {
        // server URL
        $this->url = $url;
        // debug state
        empty($debug) ? $this->debug = false : $this->debug = true;
        // message id
        $this->id = 1;
    }

    public function setAuthenticationType($new_value = 'none')
    {
        if ($new_value == 'json')
            $this->authentication_type = 'json';
        else if ($new_value == 'http')
            $this->authentication_type = 'http';
        else
            $this->authentication_type = 'none';
    }

    public function setCredentials($user = '', $password = '')
    {
        $this->authentication_user = $user;
        $this->authentication_password = $password;
    }

    /**
     * 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;
    }

    /**
     * Sets param timeout
     *
     * @param int $timeout
     */
    public function setTimeout($timeout)
    {
        $timeout = intval($timeout);
        if ($timeout) {
            $this->timeout = $timeout;
        }
    }

    /**
     * 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
        );

        if ($this->authentication_type == 'json') {
            $request['auth_user'] = $this->authentication_user;
            $request['auth_pw'] = $this->authentication_password;
        }
        $request = encoding_normalize::json_encode($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
            )
        );

        if ($this->timeout)
            $opts['http']['timeout'] = $this->timeout;

        if ($this->authentication_type == 'http') {
            $opts['http']['header'] .= sprintf("\r\nAuthorization: Basic %s", base64_encode($this->authentication_user . ':' . $this->authentication_password));
        }
        $context = stream_context_create($opts);
        if ($fp = fopen($this->url, 'r', false, $context)) {
            $raw_response = '';
            while ($row = fgets($fp)) {
                $raw_response .= trim($row) . "\n";
            }
            $this->debug && $this->debug .= '***** Server response *****' . "\n" . $raw_response . '***** End of server response *****' . "\n";
            $response = json_decode($raw_response, false);
        } else {
            throw new Exception('Unable to connect to ' . $this->url);
        }
        fclose($fp);

        // debug output
        if ($this->debug) {
            echo nl2br($this->debug);
        }

        // final checks and return
        if (! $this->notification) {
            // check that the server returned a valid JSON object
            if (! is_object($response)) {
                throw new Exception('Invalid JSON response from ' . $this->url . ': ' . substr(trim($raw_response), 0, 500));
            }
            // check the server error first: on a request parse error,
            // the server answers with a null id and the error member set
            if (isset($response->error) && ! is_null($response->error)) {
                throw new Exception('Request error: ' . encoding_normalize::json_encode($response->error));
            }
            // check
            if (! isset($response->id) || $response->id != $currentId) {
                throw new Exception('Incorrect response id (request id: ' . $currentId . ', response id: ' . ($response->id ?? '') . ')');
            }

            return $response->result ?? null;
        } else {
            return true;
        }
    }
}
