1<?php
2/**
3 * This is a PHP library that handles calling reCAPTCHA.
4 *
5 * @copyright Copyright (c) 2015, Google Inc.
6 * @link      http://www.google.com/recaptcha
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27namespace ReCaptcha;
28
29/**
30 * reCAPTCHA client.
31 */
32class ReCaptcha
33{
34    /**
35     * Version of this client library.
36     * @const string
37     */
38    const VERSION = 'php_1.1.1';
39
40    /**
41     * Shared secret for the site.
42     * @var type string
43     */
44    private $secret;
45
46    /**
47     * Method used to communicate  with service. Defaults to POST request.
48     * @var RequestMethod
49     */
50    private $requestMethod;
51
52    /**
53     * Create a configured instance to use the reCAPTCHA service.
54     *
55     * @param string $secret shared secret between site and reCAPTCHA server.
56     * @param RequestMethod $requestMethod method used to send the request. Defaults to POST.
57     */
58    public function __construct($secret, RequestMethod $requestMethod = null)
59    {
60        if (empty($secret)) {
61            throw new \RuntimeException('No secret provided');
62        }
63
64        if (!is_string($secret)) {
65            throw new \RuntimeException('The provided secret must be a string');
66        }
67
68        $this->secret = $secret;
69
70        if (!is_null($requestMethod)) {
71            $this->requestMethod = $requestMethod;
72        } else {
73            $this->requestMethod = new RequestMethod\Post();
74        }
75    }
76
77    /**
78     * Calls the reCAPTCHA siteverify API to verify whether the user passes
79     * CAPTCHA test.
80     *
81     * @param string $response The value of 'g-recaptcha-response' in the submitted form.
82     * @param string $remoteIp The end user's IP address.
83     * @return Response Response from the service.
84     */
85    public function verify($response, $remoteIp = null)
86    {
87        // Discard empty solution submissions
88        if (empty($response)) {
89            $recaptchaResponse = new Response(false, array('missing-input-response'));
90            return $recaptchaResponse;
91        }
92
93        $params = new RequestParameters($this->secret, $response, $remoteIp, self::VERSION);
94        $rawResponse = $this->requestMethod->submit($params);
95        return Response::fromJson($rawResponse);
96    }
97}
98