OAuth2.scala

  /**
   * Token for access to Google API
   * @param accessToken the token that can be sent to a Google API
   * @param refreshToken a token that may be used to obtain a new access token. Refresh tokens are valid until the user revokes access. This field is only present if access_type=offline is included in the authorization code request.
   * @param expiresIn the remaining lifetime on the access token
   * @param tokenType indicates the type of token returned. At this time, this field will always have the value Bearer
   */
  case class Token(accessToken  : String,
                   refreshToken : Option[String] = None,
                   expiresIn    : Integer,
                   tokenType    : TokenType.Value = TokenType.Bearer) extends TokenResponse{
    def refresh : Token= throw new NotImplementedException
  }

  object Token {
    abstract class Response
    abstract class Successfull extends Response
    case class OneTime() extends Successfull
    case class Refreshable() extends OneTime
    abstract class Problem extends Response
    case class ConnectionProblem() extends Problem
    case class InvalidResponse() extends Problem
    case class UnexpectedRespones() extends Problem
  }