includes/captcha/engine_default.php
author Dan
Wed, 15 Apr 2009 22:53:03 -0400
changeset 925 173aef60c13c
parent 801 eb8b23f11744
child 1081 745200a9cc2a
permissions -rw-r--r--
Added the linked-to page of the tutorial (it is, however, a stub at this point)

<?php

/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * Version 1.1.6 (Caoineag beta 1)
 * Copyright (C) 2006-2008 Dan Fuhry
 * 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);
  }
}