Code transform (WordPress plugin)

code-transform.php

<?php
/*
Plugin Name: Code transform
Plugin URI: 
Description: Based on <a href="http://1976design.com/blog/archive/2004/07/29/redesign-tag-transform/">Dunstan Orchard's tag transformations</a>, this plugin now can pull and list code snippets from flat .txt files. The plugin code is based on <a href="http://mathiasbynens.be/archive/2005/06/tag-transformations">Mathias Bynens</a>. Syntax in the post: <code>&lt;codeins="filename" /&gt;</code>. Filename to be without the extension, e.g. if the filename is <code>test.txt</code>, then the code becomes <code>&lt;codeins="test" /&gt;</code>. 
Version: 1.0
Author: ckunte
Author URI: http://ckunte.net/
*/

$dir = ABSPATH; // trailing slashed path to your WordPress installation
$iri = get_settings('siteurl') . '/';

/*
Code files should go in http://yoursite.com/path/to/wordpress/code/
   ex.   http://yoursite.com/blog/code/123a.txt
      <codeins="123a" />
*/

// this function is used to find the last occurance of a string within another string
// it's used because strrpos() only looks for a single character, not a string
function strLastPos($haystack, $needle) {
   // flip both strings around and search, then adjust position based on string lengths
   return strlen($haystack) - strlen($needle) - strpos(strrev($haystack), strrev($needle));
   }

function mj_code_transform($filename) {
   global $dir, $iri;
   $filename = 'inputfiles/' . $filename . '.txt';
   // set vars
   $list = '';
   $cmnt = '';
   $multi_line_cmnt = 0;
   $tab = '';
   $class = '';
   
   // open the file
   $file = fopen($dir . $filename, 'r')
      or die('<p><strong>Error:</strong> No such file found! Please make sure <code>' . $iri . $filename . '</code> exists.</p>');

   // for each line in the file
   while (!feof($file)) {
      // get line
      $line = fgets($file, 4096);

      // convert tags to safe entities for display
      $line = htmlentities($line);

      // count the number of tabs at the start of the line, and set the appropriate tab class
      $tab = substr_count($line, "\t");
      $tab = ($tab > 0) ? 'tab' . $tab : '';

      // remove any tabs and whitespace at the start of the line
      $line = ltrim($line);

      // find position of comment characters
      $slashslash_pos = strpos($line, '//');
      $apos_pos = strpos($line, "'");
      $slashstar_pos = strpos($line, '/*');
      $starslash_pos = strLastPos($line, '*/');

      // if it's an ongoing multi-line comment
      if ($multi_line_cmnt == 1) {
         $cmnt = 'cmnt';
         $multi_line_cmnt = 1;
         }
      
      // if it's not an ongoing multi-line comment
      if ($multi_line_cmnt <> 1) {
         // if it's a single line comment
         if (($slashslash_pos === 0) || ($apos_pos === 0)) {
            $cmnt = 'cmnt';
            $multi_line_cmnt = 0;
            }
         else {
            $cmnt = '';
            $multi_line_cmnt = 0;
            }

         // if it's potentially the start of a multi-line comment
         if ($slashstar_pos === 0) {
            $cmnt = 'cmnt';

            // if multi-line comment end string is found on the same line
            if ($starslash_pos == (strlen($line) - 3)) {
               $multi_line_cmnt = 0;
               }
            // if the multi-line comment end string is not found on the same line
            else {
               $multi_line_cmnt = 1;
               }
            }
         }

      // if the line contains the multi-line end string
      if ($starslash_pos == (strlen($line) - 3)) {
         $cmnt = 'cmnt';
         $multi_line_cmnt = 0;
         }

      // if both cmnt and tab classes are to be applied
      if ( ($cmnt <> '') && ($tab <> '') ) {
         $class = ' class="' . $tab . ' ' . $cmnt . '"';
         }
      // if only one class is to be applied
      else if ( ($cmnt <> '') || ($tab <> '') ) {
         $class = ' class="' . $tab . $cmnt . '"';
         }
      // if no classes are to be applied
      else {
         $class = '';
         }

      // remove return and other whitespace at the end of the line
      $line = rtrim($line);

      // if the line is blank, put a space in to stop some browsers collapsing the line
      if ('' == $line) {
         // insert all the information and close the list item
         $list .= '<li>&#160;</li>' . "\n";
         }
      // otherwise insert the line contents
      else {
         // insert all the information and close the list item
         $list .= '<li' . $class . '><code>' . ent2ncr($line) . '</code></li>' . "\n";
         }
      }

   // close the file handle
   fclose($file);

   // add in the link to the file
   $list .= '<li class="download">Download this example: <a href="' . $iri . $filename . '" title="Download the above code as a text file">/' . $filename . '</a></li>';

   // build the list
   $list = '<ol class="code">' . "\n" . $list . "\n" . '</ol>';
   
   // return the list
   return $list;
   }

function mj_addtags($content) {
   $content = preg_replace('!<codeins="(.*?)" />!ie', "mj_code_transform('$1')", $content);
   return $content;
}

remove_filter('the_content', 'wpautop');  // must... remove... first
remove_filter('the_excerpt', 'wpautop');
add_filter('the_content', 'mj_addtags', 10);
add_filter('the_excerpt', 'mj_addtags', 10);
add_filter('the_content', 'wpautop', 11); // then bring it back
add_filter('the_excerpt', 'wpautop', 11);

?>

style-append.css

/* CSS for styling code examples */
/* Credits: 
	Dunstan Orchard
	http://1976design.com/blog/code/456d.txt
*/	

ol.code {
	border: 1px solid #eee;
	color: #333;
	font: normal 98%/110% Courier, monospace;
	margin: 0;
	overflow: auto;
	padding: 5px 5px 5px 45px;
}

ol.code li {
	background-color: #f4f8fb;
	margin: 0;
	padding: 0 5px;
}

ol.code li.source {
	background-color: #fff;
	list-style-type: none;
	padding: 5px;
	text-align: center;
}

ol.code li+li {
	margin-top: 2px;
}

ol.code li.tab1 {padding-left: 15px;}
ol.code li.tab2 {padding-left: 30px;}
ol.code li.tab3 {padding-left: 45px;}
ol.code li.tab4 {padding-left: 60px;}
ol.code li.tab5 {padding-left: 75px;}
ol.code li.tab6 {padding-left: 90px;}

ol.code li code {
	color: #333;
}

ol.code li.cmnt  code {
	color: #824c88;
}