<?php
  // format text marked up with BBCode tags to HTML-- see
  // http://www.phpbb.com/community/faq.php?mode=bbcode for more information.
  function format_bbcode($string)\; \{$// internal function to replace BBCode tags with suitable HTML
      function _format_bbcode(string)
      {
          // use regular expression to identify and break apart BBCode tags
          while (preg_match('|\[([a-z]+)=?(.*?)\](.*?)\[/\1\]|', $string,$part,
              PREG_OFFSET_CAPTURE))
          {
              $part[2][0]\; =\; str\_replace(\text{'}"\text{'},\; "",$part[2][0]);
              $part[2][0]\; =\; str\_replace("\text{'}",\; "",$part[2][0]);
              $part[3][0]\; =\; \_format\_bbcode($part[3][0]);
              switch ($part[1][0])\; \{$// process bold, italic and underline elements
                  case 'b':
                  case 'i':
                  case 'u':
                      replace = sprintf('<\%s>\%s</\%s>', $part[1][0],$part[3][0],
                          $part[1][0]);\; break;$// process code element
                  case 'code':
                      replace = '<pre>' . $part[3][0]\; .\; \text{'}$</pre>';
                      break;
  
                  // process color styling                    
                  case 'color':
                      replace = sprintf('<span style="color: \%s">\%s</span>',
                          $part[2][0],$part[3][0]);
                      break;
  
                  // process email element
                  case 'email':
                      \%s<\a>',
                          part[3][0], $part[3][0]);\; break;$// process size styling
                  case 'size':
                      replace = sprintf('<span style="font-size: \%s">\%s</span>',
                          $part[2][0],$part[3][0]);
                      break;
  
                  // process quotes
                  case 'quote':
                      $replace\; =\; (empty($part[2][0])) ?
                          ('<blockquote><p>' . $part[3][0]\; .\; \text{'}$</p></blockquote>') :
                          sprintf('<blockquote><p>\%s wrote:<br />\%s</p>' .
                              '</blockquote>', part[2][0], $part[3][0]);\; break;$// process image element
                  case 'img':
                      replace = '<img src="' . $part[3][0]\; .\; \text{'}"\; alt=""/>\text{'};\; break;$// process hyperlink
                  case 'url':
                      replace = sprintf('<a href="\%s">\%s</a>', 
                          (!empty($part[2][0]))\; ?$part[2][0] : $part[3][0],$part[3][0]));
                      break;
  
                  // process bulleted lists
                  case 'list':
                      $replace\; =\; str\_replace(\text{'}[*]\text{'},\; \text{'}$</li><li>', part[3][0]);
                      $replace\; =\; \text{'}$<x>' . replace;
                      switch ($part[2][0])\; \{\; case\; \text{'}1\text{'}:$replace = str_replace('<x></li>',
                                  '<ol style="list-style-type: decimal">',
                                  $replace\; .\; \text{'}$</ol>');
                              break;
  
                          case 'A':
                              replace = str_replace('<x></li>',
                                  '<ol style="list-style-type: upper-alpha">',
                                  $replace\; .\; \text{'}$</ol>');
                              break;
  
                          case 'a':
                              replace = str_replace('<x></li>',
                                  '<ol style="list-style-type: lower-alpha">',
                                  $replace\; .\; \text{'}$</ol>');
                              break;
  
                          default:
                              replace = str_replace('<x></li>',
                                  '<ul>', $replace\; .\; \text{'}$</ul>');
                              break;
                      }
                      break;
  
                  default:
                      replace = $part[3][0];\; break;\; \}$string = substr_replace($string,$replace, $part[0][1],\; strlen($part[0][0]));
          }
          return $string;\; \}$// replace tags
      string = _format_bbcode($string);$// clean up line endings and add paragraph and line break tags
      string = str_replace("\r\n\r\n", '</p><p>', $string);$string = str_replace("\n\n", '</p><p>', $string);$string = str_replace("\r\n", '<br />', $string);$string = str_replace("\n", '<br />', $string);$string = '<p>' . $string\; .\; \text{'}$</p>';
      
      return string;
  }
  ?>