Run PHP-Markdown-Extra, optionally adding automatic IDs and contents table / (c) N.D.Freear

php-markdown-extra-autoid-toc.php

<?php
/**
 * Run PHP-Markdown[-Extra] [-x], optionally adding automatic IDs [-a],
 * and a table of contents [-ac].
 *
 * @copyright 2012-09-07 N.D.Freear.
 */

if (php_sapi_name() != 'cli') {
  _error('must be in CLI mode.');
}

if ($argc < 2) {
  _error('missing argument. Usage: php md.php [-x|-a|-ac] input.md > output.html');
}

$filename = $argv[$argc - 1];

$input = $interm = file_get_contents($filename);

$flag_x = $argv[1];
$flag = substr($flag_x, 0, 2);


#if ($argc > 2) {
switch ($flag) {
  case '-a':
    _log('Auto-ID mode');
    $interm = Mde_Auto_Ids::parse($input);

    if ('-ac' == $flag_x) {
      _log('Auto-ID-with-TOC mode');
      $interm = Mde_Auto_Ids::render_contents() . $interm;
    }
  case '-x': // Fall-through.
    _log('PHP-Markdown-Extra mode');
    require_once 'php-markdown-extra-1.2.5/markdown.php';
    break;
  case '-h': // Help
    _error('help!');
    break;
  default:
    if ($argc > 2) {
      _error("unrecognized flag '$flag'.");
    }
    _log('PHP-Markdown mode');
    require_once 'php-markdown-1.0.1o/markdown.php';
    break;
}


$output = Markdown($interm);


if ('-ac' == $flag_x) {
  $output = Mde_Auto_Ids::post_contents($output);
}


fwrite(STDOUT, $output);
exit (0);



// --------------------------------------------------------
// Functions.

class Mde_Auto_Ids {

  protected static $contents = array();

  public static function parse($input) {

    $toc_r = array();

    $callback = function ($matches) use (&$toc_r) {

      $level = strlen($matches[1]);

      // "My Heading 1.1" becomes, id='my-heading-1_1'
      $head = trim($matches[2]);
      $id = str_replace(' ', '-', strtolower($head));
      // Hmm, we'd prefer to replace '%' with '.', but PHP-Markdown no like!
      $id = str_replace(array('%', '.'), '_', urlencode($id));

      $output = rtrim($matches[0], "\r\n") .'  {#'. $id .'}' .PHP_EOL;

      $toc_r[] = (object) array(
        'head' => $head,
        'id' => $id,
        'level' => $level,
      );
      
      return $output;
    };
    // End callback.

    $output = preg_replace_callback(
        '/(#+)([^#]+?)\n/',
        $callback, #'_auto_ids_callback',
        $input);

    self::$contents = $toc_r;
#var_dump($toc_r);

    return $output;
  }


  public static function render_contents() {
    $toc = '{TOC}' .PHP_EOL.PHP_EOL;
    $toc .= '## Contents' .PHP_EOL.PHP_EOL;

    foreach (self::$contents as $it) {
      $R = $it->level > 1 ? ($it->level - 1) * 4 - 1 : NULL;
      $toc .= $R ? str_repeat(' ', $R) : '';
      $toc .= '* ['. $it->head .'](#'. $it->id .')' .PHP_EOL; 
    }
    $toc .= PHP_EOL. '{/TOC}' .PHP_EOL.PHP_EOL;

#var_dump($toc);
    return $toc;
  }


  public static function post_contents($input) {
    return strtr($input, array(
      '<p>{TOC}</p>' => '<div id="toc">',
      '<p>{/TOC}</p>'=> '</div>',
    ));
  }
}


function _log($msg) {
  fwrite(STDERR, '> '. $msg .PHP_EOL);
}

function _error($msg) {
  fwrite(STDERR, 'Fatal error, '. $msg .PHP_EOL);
  exit (1);
}