YouTube Video Link Convert iframe embed Link

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<?php 
//there are two types of youtube normal url
//the code below simulatneously takes care of the two.
//many codes that attempt to do this fail because they don't realize this ancient truth
  $url = "https://www.youtube.com/watch?v=q4aL9h6-WIA";
  $shortUrlRegex = '/youtu.be\/([a-zA-Z0-9_]+)\??/i';
  $longUrlRegex = '/youtube.com\/((?:embed)|(?:watch))((?:\?v\=)|(?:\/))(\w+)/i';
  if (preg_match($longUrlRegex, $url, $matches)) {
  $youtube_id = $matches[count($matches) - 1];
  }
  if (preg_match($shortUrlRegex, $url, $matches)) {
  $youtube_id = $matches[count($matches) - 1];
  }
  $fullEmbedUrl = 'https://www.youtube.com/embed/' . $youtube_id ;
?>
<!-- the embed code -->
          
<iframe id="ytplayer" type="text/html" width="560" height="400"
src="<?php echo $fullEmbedUrl ?>?rel=0&showinfo=0&color=white&iv_load_policy=3"
frameborder="0" allowfullscreen></iframe>