Youtube shortcode for WordPress

youtube-shortcode.php

/**
 * Youtube Shortcode Solution
 * 
 * Set your desired width for all the videos on your site (below)
 * Paste any Youtube video link in the shortcode, using this format, i.e.:
 * [youtube value="http://www.youtube.com/watch?feature=player_embedded&v=GGT8ZCTBoBA"]
 * This code will automatically resize your video to the appropriate size and aspect ratio.
 * Modify the width value (set to 590 here), and the iframe code below to your desired settings.
 * This requires coreylib (coreylib.com)
 * Shortcode by coreyweb: https://github.com/coreyweb
 * and collegeman: https://github.com/collegeman
 */

function youtube($atts) {
  extract(shortcode_atts(array(
    "value" => 'http://',
    "width" => '590'
  ), $atts));

  if (preg_match('#vi/(.*)/#i', $value, $matches)) {
    $id = $matches[1];
  } else if (preg_match('#v=([^&]+)#i', $value, $matches)) {
    $id = $matches[1];
  } else if (!parse_url($value, PHP_URL_HOST)) {
    $id = $value;
  } else {
    return '<a href="'.$value.'">'.$value.'</a>';
  }

  $url = 'http://www.youtube.com/watch?v='.urlencode($id);

  if ($oembed = coreylib('http://www.youtube.com/oembed?url='.$url.'&format=xml','1 month')) { 
    $newHeight = round($width * (string) $oembed->get('height') / (string) $oembed->get('width'));
    return '<iframe width="'.$width.'" height="'.$newHeight.'" src="http://www.youtube.com/embed/'.$id.'?rel=0&amp;wmode=transparent" frameborder="0" allowfullscreen></iframe>';
  } else {
    return "Couldn't access oEmbed data for ".$url;
  }
}
  
add_shortcode("youtube", "youtube");