Symfony 1.4 + PhpBB3 session integration / phpbb3 connector

<?php
/**
 * Integration with phpBB v3 forums
 * (c)Amir Wald 2008 - http://colnect.com
 * (c) modified by Robert Heim 2010 - http://blog.robert-heim.de
 *
 * see: http://forum.symfony-project.org/index.php/m/29883/
 */
class PhpbbIntegration
{
	// adjust these constants to your needs..
	const FORUM_URL = 'http://localhost:8046/';
	const FORUM_PATH = '/../../../../forum/';
	const DB_SERVER = 'localhost';
	const DB_USER = 'root';
	const DB_PASSWORD = '';
	const DB_DATABASE = 'phpbb3';
	const DB_PREFIX = 'phpbb';
	const ANONYMOUS = 1;
 
	private static $link = null;
	private static $cookies = null;
 
	/**
	 * Gets the link to phpBB database
	 *
	 * @return resource - a MySQL link identifier on success, throws Exception on error
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	public static function getDbConnection()
	{
		if (!is_null(self::$link))
		{
			return self::$link;
		}
 
		self::$link = @mysql_connect(self::DB_SERVER, self::DB_USER, self::DB_PASSWORD);
		if (self::$link && @mysql_select_db(self::DB_DATABASE, self::$link))
		{
			return self::$link;
		}
 
		throw new Exception("getDbConnection failed. MESSAGE [[file:".__FILE__.' line:'.__LINE__.": ".mysql_error()."]]");
		return self::$link;
	}
 
	/**
	 * Execute SQL query on phpBB database
	 *
	 * @param string $sql
	 * @return resource
	 */
	public static function sqlExec($sql)
	{
		if (!($result = @mysql_query($sql, self::getDbConnection()))) {
			throw new Exception("SqlExec failed. QUERY [[$sql]] MESSAGE [[".mysql_error()."]]");
		}
		return $result;
	}
 
	/**
	 * Checks if the user is logged in to the Phpbb
	 *
	 * @param integer $user_id
	 * @return boolean - true if the user is logged in to Phpbb, false otherwise
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	public static function isUserLoggedIn($user_id)
	{
		return (self::checkSession() > 0);
	}
 
	/**
	 * Validates a users session from phpBB cookies against the db.
	 *
	 * @return integer - user_id if the user is logged in to Phpbb, 0 otherwise
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	public static function checkSession()
	{
		$cookies = self::readCookies(self::getConfigVal('cookie_name'));
 
		if ($cookies['user_id'] != null && $cookies['sessionId'] != null )
		{
			// check session
			$user_id = self::checkDbSession((int)$cookies['user_id'], $cookies['sessionId']);
			if ($user_id > 0)
			{
				// user is logged in and has a valid session
				return $user_id;
			}
		}
 
		// no valid session yet.
 
		// check session-key ("remember me"-feature)
		if ($cookies['sessionKey'] == null)
		{
			// key is missing
			return 0;
		}
 
		// get/create and update session within checkDbSessionKey
		$user_id = self::checkDbSessionKey($cookies['sessionKey']);
		if ($user_id <= 0)
		{
			// the session key was not found in the db
			return 0;
		}
 
		$sessionId = self::getSessionId($cookies['user_id']);
		if ($sessionId == '')
		{
			// there was no valid session and a new one was not created during the getSessionId(...)
			// so we don't have a session and the user is not logged in.
			return 0;
		}
 
		return $user_id;
	}
 
 
	/**
	 * Get a configuration value from phpBB's database
	 *
	 * @param string $name - value name
	 * @return string - the value
	 */
	private static function getConfigVal($name)
	{
		$sql = "SELECT `config_value` FROM `".self::DB_PREFIX."_config` WHERE `config_name` LIKE '$name'";
		$result = self::sqlExec($sql);
		$ar = mysql_fetch_array($result);
		return $ar['config_value'];
	}
 
	/**
	 * Gets the session_id for a user_id from the sessions-table of te phpbb3.
	 * TODO: If there is none a new session is created. Existing sessions will be updated.
	 *
	 * @param integer $user_id
	 * @return string - session_id if the user is logged in to Phpbb, '' otherwise
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	private static function getSessionId($user_id)
	{
		if (!is_int($user_id) || $user_id < 1 || $user_id === self::ANONYMOUS) {
			return '';
		}
		$user_id = mysql_real_escape_string($user_id, self::getDbConnection());
 
		$sql = "SELECT * FROM `".self::DB_PREFIX."_sessions` WHERE `session_user_id`=$user_id";
		$result = self::sqlExec($sql);
 
		if (mysql_num_rows($result) <= 0) 
		{
			// no session found
			// TODO insert a new phpbb session  - see phpbb3/includes/session.php for how this should be done
			// TODO set $session_ar;
			return '';
		}
		else
		{
			$session_ar = mysql_fetch_array($result);
			// TODO update current phpbb session - see phpbb3/includes/session.php for how this should be done
			return $session_ar['session_id'];
		}
		return '';
	}
 
	/**
	 * Check user's session(s) from phpBB's database
	 *
	 * @param integer $user_id
	 * @param integer $sid session_id
	 * @return integer - user_id if the user is logged in to Phpbb, 0 otherwise
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	private static function checkDbSession($user_id, $sid)
	{
		if (!is_int($user_id) || $user_id < 1 || $user_id === self::ANONYMOUS) {
			return 0;
		}
		$user_id = mysql_real_escape_string($user_id, self::getDbConnection());
		$sid = mysql_real_escape_string($sid, self::getDbConnection());
 
		$sql = "SELECT * FROM `".self::DB_PREFIX."_sessions` WHERE `session_user_id`=$user_id AND `session_id` = '".$sid."'";
		$result = self::sqlExec($sql);
		if (mysql_num_rows($result) <= 0) 
		{
			// no session found
			return 0;
		}
		#$session_ar = mysql_fetch_array($result);

		return $user_id;
	}
 
	/**
	 * Validates a users session_key with the phpBB's database
	 *
	 * @param string $sessoin_key
	 * @return integer - user_id if the key is in the db, 0 otherwise
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	private static function checkDbSessionKey($session_key)
	{
		$session_key = mysql_real_escape_string($session_key, self::getDbConnection());
 
		$sql = "SELECT * FROM `".self::DB_PREFIX."_sessions_keys` WHERE `key_id`='$session_key'";
		$result = self::sqlExec($sql);
		if (mysql_num_rows($result) <= 0) 
		{
			// no session_key found
			return 0;
		}
		$session_key_ar = mysql_fetch_array($result);
 
		return (int)$session_ar['user_id'];
	}
 
	/**
	 * reads client cookies of the phpBB3
	 *
	 * @param string $phpbbCookieName
	 * @return array - $phpbbCookieName
	 * @author (c) Robert Heim 2010 - http://blog.robert-heim.de
	 */
	private static function readCookies($phpbbCookieName)
	{
		if(is_null(self::$cookies))
		{
			$sessionKey = sfContext::getInstance()->getRequest()->getCookie($phpbbCookieName.'_k');
			$user_id = sfContext::getInstance()->getRequest()->getCookie($phpbbCookieName.'_u');
			$sessionId = sfContext::getInstance()->getRequest()->getCookie($phpbbCookieName.'_sid');
			$cookies = array('sessionKey' => $sessionKey,
							'user_id' => $user_id,
							'sessionId' => $sessionId,
			);
			self::$cookies = $cookies;
		}
		return self::$cookies;
	}
 
}