<?php

/*
 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
 * Copyright (C) 2006-2009 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.
 */

/**
 * A more complex captcha engine that relies on GD.
 * @package Enano
 * @subpackage User management
 * @copyright 2007-2008 Dan Fuhry
 * @copyright 2002-2008 phpBB Group
 */
 
class captcha_engine_potpourri extends captcha_base
{
  var $captcha_config;
  
  function __construct($sid, $r = false)
  {
    parent::__construct($sid, $r);
    
    $hex = Array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F');
    $latticecolor = '#';
    for ( $i = 0; $i < 6; $i++ )
      $latticecolor .= $hex[mt_rand(0, 15)];
    
    $this->captcha_config = array (
      'width' => '350',
      'height' => '90',
      'background_color' => '#E5ECF9',
      'jpeg' => '0',
      'jpeg_quality' => '95',
      'pre_letters' => '1',
      'pre_letters_great' => '0',
      'font' => '1',
      'chess' => '2',
      'ellipses' => '2',
      'arcs' => '2',
      'lines' => '2',
      'image' => '0',
      'gammacorrect' => '0.8',
      'foreground_lattice_x' => (string)mt_rand(25, 30),
      'foreground_lattice_y' => (string)mt_rand(25, 30),
      'lattice_color' => $latticecolor,
    );
  }
  
  function make_image()
  {
    $code = $this->get_code();
    
    // Prefs
    $total_width = $this->captcha_config['width'];
    $total_height = $this->captcha_config['height'];
    
    $hex_bg_color = $this->get_rgb($this->captcha_config['background_color']);
    $bg_color = array();
    $bg_color = explode(",", $hex_bg_color);
    
    $jpeg = $this->captcha_config['jpeg'];
    $img_quality = $this->captcha_config['jpeg_quality'];
    // Max quality is 95
    
    $pre_letters = $this->captcha_config['pre_letters'];
    $pre_letter_great = $this->captcha_config['pre_letters_great'];
    $rnd_font = $this->captcha_config['font'];
    $chess = $this->captcha_config['chess'];
    $ellipses = $this->captcha_config['ellipses'];
    $arcs = $this->captcha_config['arcs'];
    $lines = $this->captcha_config['lines'];
    $image = $this->captcha_config['image'];
    
    $gammacorrect = $this->captcha_config['gammacorrect'];
    
    $foreground_lattice_y = $this->captcha_config['foreground_lattice_y'];
    $foreground_lattice_x = $this->captcha_config['foreground_lattice_x'];
    $hex_lattice_color = $this->get_rgb($this->captcha_config['lattice_color']);
    $rgb_lattice_color = array();
    $rgb_lattice_color = explode(",", $hex_lattice_color);
    
    $font_debug = false;
    
    // Fonts and images init
    if ($image)
    {
      $bg_imgs = array();
      if ($img_dir = opendir(ENANO_ROOT.'/includes/captcha/pics/'))
      {
        while (true == ($file = @readdir($img_dir))) 
        { 
          if ((substr(strtolower($file), -3) == 'jpg') || (substr(strtolower($file), -3) == 'gif'))    
          {         
            $bg_imgs[] = $file; 
          }     
        }
        closedir($img_dir);
      }
      // Grab a random Background Image or set FALSE if none was found
      $bg_img = ( count($bg_imgs) ) ? rand(0, (count($bg_imgs)-1)) : false;
    }
    
    $fonts = array();
    if ($fonts_dir = opendir(ENANO_ROOT . '/includes/captcha/fonts/'))
    {
      while (true == ($file = @readdir($fonts_dir))) 
      { 
        if ((substr(strtolower($file), strlen($file)-3, strlen($file)) == 'ttf'))
        {
          $fonts[] = $file; 
        }     
      }
      closedir($fonts_dir);
    } else {
      die('Error reading directory: '.ENANO_ROOT.'/includes/captcha/fonts/');
    }
    $font = mt_rand(0, (count($fonts)-1));
    
    // Generate
    $image = ($this->gdVersion() >= 2) ? imagecreatetruecolor($total_width, $total_height) : imagecreate($total_width, $total_height);
    $background_color = imagecolorallocate($image, $bg_color[0], $bg_color[1], $bg_color[2]);
    imagefill($image, 0, 0, $background_color);
    
    // Generate backgrund
    if ($chess == '1' || $chess == '2' && rand(0,1))
    {
      // Draw rectangles
      for($i = 0; $i <= 8; $i++)
      {
        $rectanglecolor = imagecolorallocate($image, rand(100,200),rand(100,200),rand(100,200));
        imagefilledrectangle($image, 0, 0, round($total_width-($total_width/8*$i)), round($total_height), $rectanglecolor);
        $rectanglecolor = imagecolorallocate($image, rand(100,200),rand(100,200),rand(100,200));
        imagefilledrectangle($image, 0, 0, round($total_width-($total_width/8*$i)), round($total_height/2), $rectanglecolor);
      }
    }
    if ($ellipses == '1' || $ellipses == '2' && rand(0,1))
    {
      // Draw random ellipses
      for ($i = 1; $i <= 60; $i++)
      {
        $ellipsecolor = imagecolorallocate($image, rand(100,250),rand(100,250),rand(100,250));
        imagefilledellipse($image, round(rand(0, $total_width)), round(rand(0, $total_height)), round(rand(0, $total_width/8)), round(rand(0, $total_height/4)), $ellipsecolor);	
      }
    }
    if ($arcs == '1' || $arcs == '2' && rand(0,1))
    {
      // Draw random partial ellipses
      for ($i = 0; $i <= 30; $i++)
      {
        $linecolor = imagecolorallocate($image, rand(120,255),rand(120,255),rand(120,255));
        $cx = round(rand(1, $total_width));
        $cy = round(rand(1, $total_height));
        $int_w = round(rand(1, $total_width/2));
        $int_h = round(rand(1, $total_height));
        imagearc($image, $cx, $cy, $int_w, $int_h, round(rand(0, 190)), round(rand(191, 360)), $linecolor);
        imagearc($image, $cx-1, $cy-1, $int_w, $int_h, round(rand(0, 190)), round(rand(191, 360)), $linecolor);
      }
    }
    if ($lines == '1' || $lines == '2' && rand(0,1))
    {
      // Draw random lines
      for ($i = 0; $i <= 50; $i++)
      {
        $linecolor = imagecolorallocate($image, rand(120,255),rand(120,255),rand(120,255));
        imageline($image, round(rand(1, $total_width*3)), round(rand(1, $total_height*5)), round(rand(1, $total_width/2)), round(rand(1, $total_height*2)), $linecolor);
      }
    }
    
    $text_color_array = array('255,51,0', '51,77,255', '204,51,102', '0,153,0', '255,166,2', '255,0,255', '255,0,0', '0,255,0', '0,0,255', '0,255,255');
    shuffle($text_color_array);
    $pre_text_color_array = array('255,71,20', '71,20,224', '224,71,122', '20,173,20', '255,186,22', '25,25,25');
    shuffle($pre_text_color_array);
    $white = imagecolorallocate($image, 255, 255, 255);
    $gray = imagecolorallocate($image, 100, 100, 100);
    $black = imagecolorallocate($image, 0, 0, 0);
    $lattice_color = imagecolorallocate($image, $rgb_lattice_color[0], $rgb_lattice_color[1], $rgb_lattice_color[2]);
    
    $x_char_position = (round(($total_width - 12) / strlen($code)) + mt_rand(-3, 5));
    
    for ($i = 0; $i < strlen($code); $i++)
    {
      mt_srand((double)microtime()*1000000);
    
      $char = $code{$i};
      $size = mt_rand(floor($total_height / 3.5), ceil($total_height / 2.8));
      $font = ($rnd_font) ? rand(0, (count($fonts)-1)) : $font;
      $angle = mt_rand(-30, 30);
    
      $char_pos = array();
      $char_pos = imagettfbbox($size, $angle, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
      $letter_width = abs($char_pos[0]) + abs($char_pos[4]);
      $letter_height = abs($char_pos[1]) + abs($char_pos[5]);
    
      $x_pos = ($x_char_position / 4) + ($i * $x_char_position);
      ($i == strlen($code)-1 && $x_pos >= ($total_width - ($letter_width + 5))) ? $x_pos = ($total_width - ($letter_width + 5)) : '';
      $y_pos = mt_rand(($size * 1.4 ), $total_height - ($size * 0.4));
    
    //	Pre letters
      $size = ($pre_letter_great) ? $size + (2 * $pre_letters) : $size - (2 * $pre_letters);
      for ($count = 1; $count <= $pre_letters; $count++)
      {
        $pre_angle = $angle + mt_rand(-20, 20);
    
        $text_color = $pre_text_color_array[mt_rand(0,count($pre_text_color_array)-1)];
        $text_color = explode(",", $text_color);
        $textcolor = imagecolorallocate($image, $text_color[0], $text_color[1], $text_color[2]);
    
        imagettftext($image, $size, $pre_angle, $x_pos, $y_pos-2, $white, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
        imagettftext($image, $size, $pre_angle, $x_pos+2, $y_pos, $black, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
        imagettftext($image, $size, $pre_angle, $x_pos+1, $y_pos-1, $textcolor, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
    
        $size = ($pre_letter_great) ? $size - 2 : $size + 2;
      }
    
    //	Final letters
      $text_color = $text_color_array[mt_rand(0,count($text_color_array)-1)];
      $text_color = explode(",", $text_color);
      $textcolor = imagecolorallocate($image, $text_color[0], $text_color[1], $text_color[2]);
    
      imagettftext($image, $size, $angle, $x_pos, $y_pos-2, $white, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
      imagettftext($image, $size, $angle, $x_pos+2, $y_pos, $black, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
      imagettftext($image, $size, $angle, $x_pos+1, $y_pos-1, $textcolor, ENANO_ROOT.'/includes/captcha/fonts/'.$fonts[$font], $char);
    }
    
    
    ($gammacorrect) ? imagegammacorrect($image, 1.0, $gammacorrect) : '';
    
    // Generate a white lattice in foreground
    if ($foreground_lattice_y)
    {
      // x lines
      $ih = round($total_height / $foreground_lattice_y);
      for ($i = 0; $i <= $ih; $i++)
      {
        imageline($image, 0, $i*$foreground_lattice_y, $total_width, $i*$foreground_lattice_y, $lattice_color);
      }
    }
    if ($foreground_lattice_x)
    {
      // y lines
      $iw = round($total_width / $foreground_lattice_x);
      for ($i = 0; $i <= $iw; $i++)
      {
        imageline($image, $i*$foreground_lattice_x, 0, $i*$foreground_lattice_x, $total_height, $lattice_color);
      }
    }
    
    // Font debug
    if ($font_debug && !$rnd_font)
    {
      imagestring($image, 5, 2, 0, $fonts[$font], $white);
      imagestring($image, 5, 5, 0, $fonts[$font], $white);
      imagestring($image, 5, 4, 2, $fonts[$font], $gray);
      imagestring($image, 5, 3, 1, $fonts[$font], $black);
    }
    
    // Display
    header("Last-Modified: " . gmdate("D, d M Y H:i:s") ." GMT"); 
    header("Pragma: no-cache"); 
    header("Cache-Control: no-store, no-cache, max-age=0, must-revalidate");
    (!$jpeg) ? header("Content-Type: image/png") : header("Content-Type: image/jpeg");
    
    (!$jpeg) ? imagepng($image) : imagejpeg($image, '', $img_quality);
    imagedestroy($image);
  }
  
  // Function get_rgb by Frank Burian
  // http://www.phpfuncs.org/?content=show&id=46
  function get_rgb($hex) { 
    $hex_array = array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 
        'A' => 10, 'B' => 11, 'C' => 12, 'D' => 13, 'E' => 14, 
        'F' => 15); 
    $hex = str_replace('#', '', strtoupper($hex)); 
    if (($length = strlen($hex)) == 3) { 
        $hex = $hex{0}.$hex{0}.$hex{1}.$hex{1}.$hex{2}.$hex{2}; 
        $length = 6; 
    } 
    if ($length != 6 or strlen(str_replace(array_keys($hex_array), '', $hex))) 
        return NULL; 
    $rgb['r'] = $hex_array[$hex{0}] * 16 + $hex_array[$hex{1}]; 
    $rgb['g'] = $hex_array[$hex{2}] * 16 + $hex_array[$hex{3}]; 
    $rgb['b']= $hex_array[$hex{4}] * 16 + $hex_array[$hex{5}]; 
    return $rgb['r'].','.$rgb['g'].','.$rgb['b']; 
  }
  
  // Function  gdVersion by Hagan Fox
  // http://de3.php.net/manual/en/function.gd-info.php#52481
  function gdVersion($user_ver = 0)
  {
     if (! extension_loaded('gd')) { return; }
     static $gd_ver = 0;
     // Just accept the specified setting if it's 1.
     if ($user_ver == 1) { $gd_ver = 1; return 1; }
     // Use the static variable if function was called previously.
     if ($user_ver !=2 && $gd_ver > 0 ) { return $gd_ver; }
     // Use the gd_info() function if possible.
     if (function_exists('gd_info')) {
         $ver_info = gd_info();
         preg_match('/\d/', $ver_info['GD Version'], $match);
         $gd_ver = $match[0];
         return $match[0];
     }
     // If phpinfo() is disabled use a specified / fail-safe choice...
     if (preg_match('/phpinfo/', ini_get('disable_functions'))) {
         if ($user_ver == 2) {
             $gd_ver = 2;
             return 2;
         } else {
             $gd_ver = 1;
             return 1;
         }
     }
     // ...otherwise use phpinfo().
     ob_start();
     phpinfo(8);
     $info = ob_get_contents();
     ob_end_clean();
     $info = stristr($info, 'gd version');
     preg_match('/\d/', $info, $match);
     $gd_ver = $match[0];
     return $match[0];
  }
}