woraperth

// Get Youtube URL
$yturl = 'https://www.youtube.com/watch?v=HhAKNSsb4t4';
preg_match("/^(?:http(?:s)?:\/\/)?(?:www\.)?(?:m\.)?(?:youtu\.be\/|youtube\.com\/(?:(?:watch)?\?(?:.*&)?v(?:i)?=|(?:embed|v|vi|user)\/))([^\?&\"'>]+)/", $yturl, $matches);

$video_id = $matches[1];

// Get Thumbnail
$file_headers = get_headers( 'http://img.youtube.com/vi/' . $video_id . '/maxresdefault.jpg' );
$is_404 = $file_headers[0] == 'HTTP/1.0 404 Not Found' || false !== strpos( $file_headers[0], '404 Not Found' );
$video_thumbnail_url = $is_404 ? 'http://img.youtube.com/vi/' . $youtube_id . '/maxresdefault.jpg' : 'http://img.youtube.com/vi/' . $video_id . '/hqdefault.jpg';

philipnewcomer

<?php
/**
 * Recursive function to generate a unique username.
 *
 * If the username already exists, will add a numerical suffix which will increase until a unique username is found.
 *
 * @param string $username
 *
 * @return string The unique username.
 */