Auth middleware issue

Auth.scala

trait Auth {
   def authenticate(token: Token): Future[User]
}

class OktaAuth(client: RestClient) extends Auth { 
   def authenticate(token: Token): Future[User] = ???
}

class MockAuth(users: Map[Token, User]) extends Auth { 
  def authenticate(token: Token): Future[User] = ???
}

class CachedAuth(cache: Cache, underlying: Auth) extends Auth { 
  def authenticate(token: Token): Future[User] = ???
}

AuthMiddleWare.scala

object AuthMiddleware {

  def checkUser(request: Request, auth: Auth, env: Env) =
    (env, auth) match {
      case (Prod, _: MockAuth) => InternalServerError() 
      case _ => // doesn't handle CachedAuth!
        request.headers.get("Authorization") match {
          case None        => reject(Forbidden())
          case Some(token) =>
            auth.authenticate(token).map(user =>
              provide(user)
            )
        }

    }
  
}

env.conf

{
  auth : {
    type    : "Okta"
    baseUrl : "https://okta.com/auth0"
    api-key : "X28fd-OS0-8S"
  }
}

{
  auth : {
    type : "Mock"
    users : {
      "bob" : "abcd"
      "eda" : "xxxx"
    }
  }
}

{
  auth : {
    type : "Cached"
    underlying : {
      type    : "Okta"
      baseUrl : "https://okta.com/auth0"
      api-key : "X28fd-OS0-8S"
    },
    cacheSize : 100
  }
}

Env.scala

sealed trait Env {

object Env {
  case object Local extends Env
  case object UAT   extends Env
  ase object Prod   extends Env
}