<?php

/*

 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

 * captcha.php - visual confirmation system used during registration

 *

 * This program is Free Software; you can redistribute 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.

 *

 * This program 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 details.

 *

 * This file contains code written by Paul Sohier (www.paulscripts.nl). The CAPTCHA code was ported from the phpBB Better

 * Captcha mod, and has been released under the GPLv2 by the original author.

 */

/**

 * The default CAPTCHA engine. Generates medium-strength captchas with very good performance.

 * @package Enano

 * @subpackage User management

 * @copyright 2007-2008 Dan Fuhry

 * @copyright Paul Sohier

 */

class captcha_engine_default extends captcha_base

{

  function make_image()

  {

    $code =& strtoupper($this->get_code());

    /**

      * The next part is orginnaly written by ted from mastercode.nl and modified for use in Enano.

      **/

    header("content-type:image/png");

    header('Cache-control: no-cache, no-store');

    $breedte = 320;

    $hoogte = 60;

    $img = imagecreatetruecolor($breedte,$hoogte);

    $achtergrond = imagecolorallocate($img, $this->color("bg"), $this->color("bg"), $this->color("bg"));

    imagefilledrectangle($img, 0, 0, $breedte-1, $hoogte-1, $achtergrond);

    for($g = 0;$g < 30; $g++)

    {

      $t = $this->dss_rand();

      $t = $t[0];

      $ypos = rand(0,$hoogte);

      $xpos = rand(0,$breedte);

      $kleur = imagecolorallocate($img, $this->color("bgtekst"), $this->color("bgtekst"), $this->color("bgtekst"));

      imagettftext($img, $this->size(), $this->move(), $xpos, $ypos, $kleur, $this->font(), $t);

    } 			

    $stukje = $breedte / (strlen($code) + 3);

    for($j = 0;$j < strlen($code); $j++)

    {

      $tek = $code[$j];

      $ypos = rand(33,43);

      $xpos = $stukje * ($j+1);

      $kleur2 = imagecolorallocate($img, $this->color("tekst"), $this->color("tekst"), $this->color("tekst"));

      imagettftext($img, $this->size(), $this->move(), $xpos, $ypos, $kleur2, $this->font() , $tek);

    }

    imagepng($img);

  }

  /**

    * Some functions :)

    * Also orginally written by mastercode.nl

    **/

  /**

    * Function to create a random color

    * @param $type string Mode for the color

    * @return int

    **/

  function color($type)

  {

    switch($type)

    {

      case "bg": 

        $kleur = rand(224,255); 

      break;

      case "tekst": 

        $kleur = rand(0,127); 

      break;

      case "bgtekst": 

        $kleur = rand(200,224); 

      break;

      default: 

        $kleur = rand(0,255); 

      break;

    }

    return $kleur;

  }

  /**

    * Function to ranom the size

    * @return int

    **/

  function size()

  {

    $grootte = rand(14,30);

    return $grootte;

  }

  /**

    * Function to random the posistion

    * @return int

    **/

  function move()

  {

    $draai = rand(-25,25);

    return $draai;

  }

  /**

    * Function to return a ttf file from fonts map

    * @return string

    **/

  function font()

  {

    $f = @opendir(ENANO_ROOT . '/includes/captcha/fonts/');

    if(!$f) die('Can\'t open includes/captcha/fonts/ for reading');

    $ar = array();

    while(($file = @readdir($f)) !== false)

    {

      if(!in_array($file, array('.','..')) && strstr($file, '.ttf'))

      {

        $ar[] = $file;

      }

    }

    if(count($ar))

    {

      shuffle($ar);

      $i = rand(0,(count($ar) - 1));

      return ENANO_ROOT . '/includes/captcha/fonts/' . $ar[$i];

    }

  }

  function dss_rand()

  {

    $val = microtime() .  mt_rand();

    $val = md5($val . 'a');

    return substr($val, 4, 16);

  }

}