class.YoutubeUrl

<?php

class YoutubeUrl
{
    private static $isValid = false;

    /**
     * Returns with the Youtube video ID from the full URL.
     *
     * @param string $url
     * @return string
     */
    public function getID($url)
    {

        if(self::$isValid == false) { exit(); }
        if(!strpos($url, "#!v=") === false) { $url = str_replace("#!v=", "?v=", $url); }

        parse_str(parse_url($url, PHP_URL_QUERY));

        if(isset($v)) { return $v; }
        else { return substr($url, strrpos($url, "/") +1, 11); }
    }

    /**
     * Generates the proper Youtube link to the video from the id
     *
     * @param string $id
     * @return string
     */
    public function generateLink($id)
    {
        if(self::$isValid == false) { exit(); }
        $generatedLink = "http://www.youtube.com/watch?v=" . trim($id);
        return $generatedLink;
    }

    /**
     * Creates the embed code for the video
     *
     * @param string $id video id
     * @param int $width playbackframe width (def: 320)
     * @param int $height playbackframe height (def: 240)
     * @return string
     */
    public function generateEmbedded($id, $width=320, $height=240)
    {
        if(self::$isValid == false) { exit(); }

        $embedCode =  '<object width="' . $width . '" height="' . $height . '">';
        $embedCode .= '<param name="movie" value="http://www.youtube.com/v/' . $id . '?fs=1&hl=pt_BR&rel=0"></param>';
        $embedCode .= '<param name="allowFullScreen" value="true"></param>';
        $embedCode .= '<param name="allowscriptaccess" value="always"></param>';
        $embedCode .= '<embed src="http://www.youtube.com/v/' . $id . '?fs=1&hl=pt_BR&rel=0"';
        $embedCode .= 'type="application/x-shockwave-flash"';
        $embedCode .= 'allowscriptaccess="always"';
        $embedCode .= 'allowfullscreen="true"';
        $embedCode .= 'width="' . $width . '"';
        $embedCode .= 'height="' . $height . '">';
        $embedCode .= '</embed>';
        $embedCode .= '</object>';

        return $embedCode;
    }

    /**
     * Creates the embed code
     *
     * @param string $url
     * @param int $width
     * @param int $height
     */
    public function url2Embedded($url, $width=320, $height=240)
    {
        if(self::$isValid == false) { exit(); }

        echo $this->generateEmbedded($this->getID($url), $width, $height);
    }

    /**
     * Validates the Youtube video URL
     *
     * @param string $url YT video url
     */
    public function validateYtUrl($url)
    {
        $url = substr($url, 0, 42);
        $p_url = parse_url($url);

        if(empty($p_url['scheme'])) { $scheme = ""; self::$isValid = false; }
        else { $scheme = $p_url['scheme']; }

        if(empty($p_url['host'])) { $host = ""; self::$isValid = false; }
        else { $host = $p_url['host']; }

        if(empty($p_url['path'])) { $path = ""; self::$isValid = false; }
        else { $path = $p_url['path']; }

        if(empty($p_url['query'])) { $query = ""; self::$isValid = false; }
        else { $query = $p_url['query']; }

        if($scheme != "http" || $host != "www.youtube.com" || $path != "/watch" || strlen($query) != 13) { self::$isValid = false; }
        else { self::$isValid = true; }

        return self::$isValid;
    }

    /**
     * Returns with the validity of the URL
     *
     * @return bool
     */
    public function isUrlValid()
    {
        if(self::$isValid == false) { return false; }
        elseif(self::$isValid == true) { return true; }
    }

    public function ytUrlParser($url)
    {
        $url = substr($url, 0, 42);
        $p_url = parse_url($url);
        echo substr($p_url['query'], 0, 13) . '<br />';
        print_r($p_url);
    }
}

?>