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

package jdocs.tutorial_5;

import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import akka.actor.ActorRef;
import akka.actor.ActorSystem;
import akka.actor.PoisonPill;
import akka.testkit.javadsl.TestKit;

import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;

import org.scalatest.junit.JUnitSuite;

import static jdocs.tutorial_5.DeviceGroupQueryTest.assertEqualTemperatures;

public class DeviceGroupTest extends JUnitSuite {

  static ActorSystem system;

  @BeforeClass
  public static void setup() {
    system = ActorSystem.create();
  }

  @AfterClass
  public static void teardown() {
    TestKit.shutdownActorSystem(system);
    system = null;
  }

  @Test
  public void testRegisterDeviceActor() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor1 = probe.getLastSender();

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device2"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor2 = probe.getLastSender();
    assertNotEquals(deviceActor1, deviceActor2);

    // Check that the device actors are working
    deviceActor1.tell(new Device.RecordTemperature(0L, 1.0), probe.getRef());
    assertEquals(0L, probe.expectMsgClass(Device.TemperatureRecorded.class).requestId);
    deviceActor2.tell(new Device.RecordTemperature(1L, 2.0), probe.getRef());
    assertEquals(1L, probe.expectMsgClass(Device.TemperatureRecorded.class).requestId);
  }

  @Test
  public void testIgnoreRequestsForWrongGroupId() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("wrongGroup", "device1"), probe.getRef());
    probe.expectNoMsg();
  }

  @Test
  public void testReturnSameActorForSameDeviceId() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor1 = probe.getLastSender();

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor2 = probe.getLastSender();
    assertEquals(deviceActor1, deviceActor2);
  }

  @Test
  public void testListActiveDevices() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device2"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);

    groupActor.tell(new DeviceGroup.RequestDeviceList(0L), probe.getRef());
    DeviceGroup.ReplyDeviceList reply = probe.expectMsgClass(DeviceGroup.ReplyDeviceList.class);
    assertEquals(0L, reply.requestId);
    assertEquals(Stream.of("device1", "device2").collect(Collectors.toSet()), reply.ids);
  }

  @Test
  public void testListActiveDevicesAfterOneShutsDown() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef toShutDown = probe.getLastSender();

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device2"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);

    groupActor.tell(new DeviceGroup.RequestDeviceList(0L), probe.getRef());
    DeviceGroup.ReplyDeviceList reply = probe.expectMsgClass(DeviceGroup.ReplyDeviceList.class);
    assertEquals(0L, reply.requestId);
    assertEquals(Stream.of("device1", "device2").collect(Collectors.toSet()), reply.ids);

    probe.watch(toShutDown);
    toShutDown.tell(PoisonPill.getInstance(), ActorRef.noSender());
    probe.expectTerminated(toShutDown);

    // using awaitAssert to retry because it might take longer for the groupActor
    // to see the Terminated, that order is undefined
    probe.awaitAssert(() -> {
      groupActor.tell(new DeviceGroup.RequestDeviceList(1L), probe.getRef());
      DeviceGroup.ReplyDeviceList r = 
        probe.expectMsgClass(DeviceGroup.ReplyDeviceList.class);
      assertEquals(1L, r.requestId);
      assertEquals(Stream.of("device2").collect(Collectors.toSet()), r.ids);
      return null;
    });
  }

  //#group-query-integration-test
  @Test
  public void testCollectTemperaturesFromAllActiveDevices() {
    TestKit probe = new TestKit(system);
    ActorRef groupActor = system.actorOf(DeviceGroup.props("group"));

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device1"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor1 = probe.getLastSender();

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device2"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor2 = probe.getLastSender();

    groupActor.tell(new DeviceManager.RequestTrackDevice("group", "device3"), probe.getRef());
    probe.expectMsgClass(DeviceManager.DeviceRegistered.class);
    ActorRef deviceActor3 = probe.getLastSender();

    // Check that the device actors are working
    deviceActor1.tell(new Device.RecordTemperature(0L, 1.0), probe.getRef());
    assertEquals(0L, probe.expectMsgClass(Device.TemperatureRecorded.class).requestId);
    deviceActor2.tell(new Device.RecordTemperature(1L, 2.0), probe.getRef());
    assertEquals(1L, probe.expectMsgClass(Device.TemperatureRecorded.class).requestId);
    // No temperature for device 3

    groupActor.tell(new DeviceGroup.RequestAllTemperatures(0L), probe.getRef());
    DeviceGroup.RespondAllTemperatures response = probe.expectMsgClass(DeviceGroup.RespondAllTemperatures.class);
    assertEquals(0L, response.requestId);

    Map<String, DeviceGroup.TemperatureReading> expectedTemperatures = new HashMap<>();
    expectedTemperatures.put("device1", new DeviceGroup.Temperature(1.0));
    expectedTemperatures.put("device2", new DeviceGroup.Temperature(2.0));
    expectedTemperatures.put("device3", new DeviceGroup.TemperatureNotAvailable());

    assertEqualTemperatures(expectedTemperatures, response.temperatures);
  }
  //#group-query-integration-test
}