<?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.
 *
 * @codingStandardsIgnoreFile
 */

namespace ReCaptcha;

/**
 * reCAPTCHA client.
 *
 * @ignore
 */
class ReCaptcha {

	/**
	 * Version of this client library.
	 *
	 * @const string
	 */
	const VERSION = 'php_1.1.2';

	/**
	 * Shared secret for the site.
	 *
	 * @var string
	 */
	private $secret;

	/**
	 * Method used to communicate with service. Defaults to POST request.
	 *
	 * @var RequestMethod
	 */
	private $requestMethod;

	/**
	 * Create a configured instance to use the reCAPTCHA service.
	 *
	 * @param string        $secret shared secret between site and reCAPTCHA server.
	 * @param RequestMethod $requestMethod method used to send the request. Defaults to POST.
	 * @throws \RuntimeException if $secret is invalid
	 * @ignore
	 */
	public function __construct( $secret, RequestMethod $requestMethod = null ) {
		if ( empty( $secret ) ) {
			throw new \RuntimeException( 'No secret provided' );
		}

		if ( ! is_string( $secret ) ) {
			throw new \RuntimeException( 'The provided secret must be a string' );
		}

		$this->secret = $secret;

		if ( ! is_null( $requestMethod ) ) {
			$this->requestMethod = $requestMethod;
		} else {
			$this->requestMethod = new RequestMethod\Post();
		}
	}

	/**
	 * Calls the reCAPTCHA siteverify API to verify whether the user passes
	 * CAPTCHA test.
	 *
	 * @param string $response The value of 'g-recaptcha-response' in the submitted form.
	 * @param string $remoteIp The end user's IP address.
	 * @return Response Response from the service.
	 * @ignore
	 */
	public function verify( $response, $remoteIp = null ) {
		// Discard empty solution submissions
		if ( empty( $response ) ) {
			$recaptchaResponse = new Response( false, array( 'missing-input-response' ) );
			return $recaptchaResponse;
		}

		$params      = new RequestParameters( $this->secret, $response, $remoteIp, self::VERSION );
		$rawResponse = $this->requestMethod->submit( $params );
		return Response::fromJson( $rawResponse );
	}
}
