<?php

/**

 * This is a PHP library that handles calling reCAPTCHA.

 *

 * @copyright Copyright (c) 2015, Google Inc.

 * @link      http://www.google.com/recaptcha

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */



namespace ReCaptcha\RequestMethod;



use ReCaptcha\RequestMethod;

use ReCaptcha\RequestParameters;



/**

 * Sends a POST request to the reCAPTCHA service, but makes use of fsockopen()

 * instead of get_file_contents(). This is to account for people who may be on

 * servers where allow_furl_open is disabled.

 */

class SocketPost implements RequestMethod

{

    /**

     * reCAPTCHA service host.

     * @const string

     */

    const RECAPTCHA_HOST = 'www.google.com';



    /**

     * @const string reCAPTCHA service path

     */

    const SITE_VERIFY_PATH = '/recaptcha/api/siteverify';



    /**

     * @const string Bad request error

     */

    const BAD_REQUEST = '{"success": false, "error-codes": ["invalid-request"]}';



    /**

     * @const string Bad response error

     */

    const BAD_RESPONSE = '{"success": false, "error-codes": ["invalid-response"]}';



    /**

     * Socket to the reCAPTCHA service

     * @var Socket

     */

    private $socket;



    /**

     * Constructor

     *

     * @param \ReCaptcha\RequestMethod\Socket $socket optional socket, injectable for testing

     */

    public function __construct(Socket $socket = null)

    {

        if (!is_null($socket)) {

            $this->socket = $socket;

        } else {

            $this->socket = new Socket();

        }

    }



    /**

     * Submit the POST request with the specified parameters.

     *

     * @param RequestParameters $params Request parameters

     * @return string Body of the reCAPTCHA response

     */

    public function submit(RequestParameters $params)

    {

        $errno = 0;

        $errstr = '';



        if (false === $this->socket->fsockopen('ssl://' . self::RECAPTCHA_HOST, 443, $errno, $errstr, 30)) {

            return self::BAD_REQUEST;

        }



        $content = $params->toQueryString();



        $request = "POST " . self::SITE_VERIFY_PATH . " HTTP/1.1\r\n";

        $request .= "Host: " . self::RECAPTCHA_HOST . "\r\n";

        $request .= "Content-Type: application/x-www-form-urlencoded\r\n";

        $request .= "Content-length: " . strlen($content) . "\r\n";

        $request .= "Connection: close\r\n\r\n";

        $request .= $content . "\r\n\r\n";



        $this->socket->fwrite($request);

        $response = '';



        while (!$this->socket->feof()) {

            $response .= $this->socket->fgets(4096);

        }



        $this->socket->fclose();



        if (0 !== strpos($response, 'HTTP/1.1 200 OK')) {

            return self::BAD_RESPONSE;

        }



        $parts = preg_split("#\n\s*\n#Uis", $response);



        return $parts[1];

    }

}

