/*
 * Copyright (C) 2009-2018 Lightbend Inc. <https://www.lightbend.com>
 */

package akka.remote.artery

import scala.concurrent.duration._
import com.typesafe.config.ConfigFactory
import akka.actor.Actor
import akka.actor.ActorIdentity
import akka.actor.ActorRef
import akka.actor.Deploy
import akka.actor.Identify
import akka.actor.PoisonPill
import akka.actor.Props
import akka.actor.RootActorPath
import akka.actor.Terminated
import akka.testkit.ImplicitSender
import akka.testkit.TestProbe
import akka.actor.ActorSelection
import akka.testkit.TestEvent
import akka.event.Logging
import akka.remote.RARP
import akka.testkit.EventFilter
import akka.testkit.JavaSerializable

object UntrustedSpec {
  final case class IdentifyReq(path: String) extends JavaSerializable
  final case class StopChild(name: String) extends JavaSerializable

  class Receptionist(testActor: ActorRef) extends Actor {
    context.actorOf(Props(classOf[Child], testActor), "child1")
    context.actorOf(Props(classOf[Child], testActor), "child2")
    context.actorOf(Props(classOf[FakeUser], testActor), "user")

    def receive = {
      case IdentifyReq(path) ⇒ context.actorSelection(path).tell(Identify(None), sender())
      case StopChild(name)   ⇒ context.child(name) foreach context.stop
      case msg               ⇒ testActor forward msg
    }
  }

  class Child(testActor: ActorRef) extends Actor {
    override def postStop(): Unit = {
      testActor ! s"${self.path.name} stopped"
    }
    def receive = {
      case msg ⇒ testActor forward msg
    }
  }

  class FakeUser(testActor: ActorRef) extends Actor {
    context.actorOf(Props(classOf[Child], testActor), "receptionist")
    def receive = {
      case msg ⇒ testActor forward msg
    }
  }

  val config = ConfigFactory.parseString(
    """
      akka.remote.artery.untrusted-mode = on
      akka.remote.artery.trusted-selection-paths = ["/user/receptionist", ]
      akka.loglevel = DEBUG # test verifies debug
    """
  ).withFallback(ArterySpecSupport.defaultConfig)

}

class UntrustedSpec extends ArteryMultiNodeSpec(UntrustedSpec.config) with ImplicitSender {

  import UntrustedSpec._

  val client = newRemoteSystem(name = Some("UntrustedSpec-client"))
  val address = RARP(system).provider.getDefaultAddress

  val receptionist = system.actorOf(Props(classOf[Receptionist], testActor), "receptionist")

  lazy val remoteDaemon = {
    {
      val p = TestProbe()(client)
      client.actorSelection(RootActorPath(address) / receptionist.path.elements).tell(IdentifyReq("/remote"), p.ref)
      p.expectMsgType[ActorIdentity].ref.get
    }
  }

  lazy val target2 = {
    val p = TestProbe()(client)
    client.actorSelection(RootActorPath(address) / receptionist.path.elements).tell(
      IdentifyReq("child2"), p.ref)
    p.expectMsgType[ActorIdentity].ref.get
  }

  // need to enable debug log-level without actually printing those messages
  system.eventStream.publish(TestEvent.Mute(EventFilter.debug()))

  "UntrustedMode" must {

    "allow actor selection to configured white list" in {
      val sel = client.actorSelection(RootActorPath(address) / receptionist.path.elements)
      sel ! "hello"
      expectMsg("hello")
    }

    "discard harmful messages to /remote" in {
      val logProbe = TestProbe()
      // but instead install our own listener
      system.eventStream.subscribe(system.actorOf(Props(new Actor {
        import Logging._
        def receive = {
          case d @ Debug(_, _, msg: String) if msg contains "dropping" ⇒ logProbe.ref ! d
          case _ ⇒
        }
      }).withDeploy(Deploy.local), "debugSniffer"), classOf[Logging.Debug])

      remoteDaemon ! "hello"
      logProbe.expectMsgType[Logging.Debug]
    }

    "discard harmful messages to testActor" in {
      target2 ! Terminated(remoteDaemon)(existenceConfirmed = true, addressTerminated = false)
      target2 ! PoisonPill
      client.stop(target2)
      target2 ! "blech"
      expectMsg("blech")
    }

    "discard watch messages" in {
      client.actorOf(Props(new Actor {
        context.watch(target2)
        def receive = {
          case x ⇒ testActor forward x
        }
      }).withDeploy(Deploy.local))
      receptionist ! StopChild("child2")
      expectMsg("child2 stopped")
      // no Terminated msg, since watch was discarded
      expectNoMsg(1.second)
    }

    "discard actor selection" in {
      val sel = client.actorSelection(RootActorPath(address) / testActor.path.elements)
      sel ! "hello"
      expectNoMsg(1.second)
    }

    "discard actor selection with non root anchor" in {
      val p = TestProbe()(client)
      client.actorSelection(RootActorPath(address) / receptionist.path.elements).tell(
        Identify(None), p.ref)
      val clientReceptionistRef = p.expectMsgType[ActorIdentity].ref.get

      val sel = ActorSelection(clientReceptionistRef, receptionist.path.toStringWithoutAddress)
      sel ! "hello"
      expectNoMsg(1.second)
    }

    "discard actor selection to child of matching white list" in {
      val sel = client.actorSelection(RootActorPath(address) / receptionist.path.elements / "child1")
      sel ! "hello"
      expectNoMsg(1.second)
    }

    "discard actor selection with wildcard" in {
      val sel = client.actorSelection(RootActorPath(address) / receptionist.path.elements / "*")
      sel ! "hello"
      expectNoMsg(1.second)
    }

    "discard actor selection containing harmful message" in {
      val sel = client.actorSelection(RootActorPath(address) / receptionist.path.elements)
      sel ! PoisonPill
      expectNoMsg(1.second)
    }

  }

}
