pekko/akka-camel/src/main/scala/akka/camel/Activation.scala

/**
 * Copyright (C) 2009-2012 Typesafe Inc. <http://www.typesafe.com>
 */

package akka.camel

import akka.camel.internal._
import akka.util.Timeout
import akka.actor.{ ActorSystem, Props, ActorRef }
import akka.pattern._
import scala.concurrent.util.Duration
import concurrent.{ ExecutionContext, Future }

/**
 * Activation trait that can be used to wait on activation or de-activation of Camel endpoints.
 * The Camel endpoints are activated asynchronously. This trait can signal when an endpoint is activated or de-activated.
 */
trait Activation {
  def system: ActorSystem //FIXME Why is this here, what's it needed for and who should use it?

  private val activationTracker = system.actorOf(Props[ActivationTracker], "camelActivationTracker") //FIXME Why is this also top level?

  /**
   * Produces a Future with the specified endpoint that will be completed when the endpoint has been activated,
   * or if it times out, which will happen after the specified Timeout.
   *
   * @param endpoint the endpoint to be activated
   * @param timeout the timeout for the Future
   */
  def activationFutureFor(endpoint: ActorRef)(implicit timeout: Duration, executor: ExecutionContext): Future[ActorRef] =
    (activationTracker.ask(AwaitActivation(endpoint))(Timeout(timeout))).map[ActorRef]({
      case EndpointActivated(`endpoint`)               ⇒ endpoint
      case EndpointFailedToActivate(`endpoint`, cause) ⇒ throw cause
    })

  /**
   * Produces a Future which will be completed when the given endpoint has been deactivated or
   * or if it times out, which will happen after the specified Timeout.
   *
   * @param endpoint the endpoint to be deactivated
   * @param timeout the timeout of the Future
   */
  def deactivationFutureFor(endpoint: ActorRef)(implicit timeout: Duration, executor: ExecutionContext): Future[ActorRef] =
    (activationTracker.ask(AwaitDeActivation(endpoint))(Timeout(timeout))).map[ActorRef]({
      case EndpointDeActivated(`endpoint`)               ⇒ endpoint
      case EndpointFailedToDeActivate(`endpoint`, cause) ⇒ throw cause
    })
}