/home/edulekha/studygroup.edulekha.com/ow_system_plugins/base/controllers/captcha.php
<?php

/**
 * EXHIBIT A. Common Public Attribution License Version 1.0
 * The contents of this file are subject to the Common Public Attribution License Version 1.0 (the “License”);
 * you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.oxwall.org/license. The License is based on the Mozilla Public License Version 1.1
 * but Sections 14 and 15 have been added to cover use of software over a computer network and provide for
 * limited attribution for the Original Developer. In addition, Exhibit A has been modified to be consistent
 * with Exhibit B. Software distributed under the License is distributed on an “AS IS” basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language
 * governing rights and limitations under the License. The Original Code is Oxwall software.
 * The Initial Developer of the Original Code is Oxwall Foundation (http://www.oxwall.org/foundation).
 * All portions of the code written by Oxwall Foundation are Copyright (c) 2011. All Rights Reserved.

 * EXHIBIT B. Attribution Information
 * Attribution Copyright Notice: Copyright 2011 Oxwall Foundation. All rights reserved.
 * Attribution Phrase (not exceeding 10 words): Powered by Oxwall community software
 * Attribution URL: http://www.oxwall.org/
 * Graphic Image as provided in the Covered Code.
 * Display of Attribution Information is required in Larger Works which are defined in the CPAL as a work
 * which combines Covered Code or portions thereof with code not governed by the terms of the CPAL.
 */

/**
 * Captcha controller
 *
 * @author Podyachev Evgeny <joker.OW2@gmail.com>
 * @package ow_system_plugins.base.controllers
 * @since 1.0
 */
class BASE_CTRL_Captcha extends OW_ActionController
{
    const CAPTCHA_WIDTH = 200;
    const CAPTCHA_HEIGHT = 68;

    public function __construct()
    {
        parent::__construct();

        require_once OW_DIR_LIB . 'securimage/securimage.php';
    }

    public function index( $params )
    {
        $img = new securimage();

        //Change some settings
        $img->image_width = !empty($_GET['width']) ? (int) $_GET['width'] : self::CAPTCHA_WIDTH;
        $img->image_height = !empty($_GET['height']) ? (int) $_GET['height'] : self::CAPTCHA_HEIGHT;
        $img->perturbation = 0.45;
        $img->image_bg_color = new Securimage_Color(0xf6, 0xf6, 0xf6);
        $img->text_angle_minimum = -5;
        $img->text_angle_maximum = 5;
        $img->use_transparent_text = true;
        $img->text_transparency_percentage = 30; // 100 = completely transparent
        $img->num_lines = 7;
        $img->line_color = new Securimage_Color("#7B92AA");
        $img->signature_color = new Securimage_Color("#7B92AA");
        $img->text_color = new Securimage_Color("#7B92AA");
        $img->use_wordlist = true;

        $img->show();
        exit;
    }

    public function ajaxResponder()
    {
        if ( empty($_POST["command"]) || !OW::getRequest()->isAjax() )
        {
            throw new Redirect404Exception();
        }

        $command = (string) $_POST["command"];

        switch ( $command )
        {
            case 'checkCaptcha':

                $value = $_POST["value"];

                $result = UTIL_Validator::isCaptchaValid($value);

                if ( $result )
                {
                    OW::getSession()->set('securimage_code_value', $value);
                }

                echo json_encode(array('result' => $result));

                break;
        }
        
        exit();
    }
}