class Database extends mysqli
{
	private static
		$instance = null;

	private
		$host = DB_HOST,
		$user = DB_USER,
		$password = DB_PASSWORD,
		$database = DB_DATABASE;

	private function __construct()
	{
		@parent::__construct(
			$this->host,
			$this->user,
			$this->password,
			$this->database
		);

		if (mysqli_connect_errno())
		{
			throw new Exception(
				mysqli_connect_error(),
				mysqli_connect_errno()
			);
		}
	}

	public static function get_instance()
	{

		if (!isset($instance)) {
			$c = __CLASS__;
			$instance = new $c;
		}

		return $instance;
	}

	public function __clone()
	{
		throw new Exception("Cannot clone ".__CLASS__." class");
	}
}