/**
 * Copyright (C) 2009-2017 Lightbend Inc. <http://www.lightbend.com>
 */
package akka.cluster.sharding

import java.io.File

import akka.actor._
import akka.cluster.{ Cluster, MemberStatus }
import akka.persistence.Persistence
import akka.persistence.journal.leveldb.{ SharedLeveldbJournal, SharedLeveldbStore }
import akka.remote.testconductor.RoleName
import akka.remote.testkit.{ MultiNodeConfig, MultiNodeSpec, STMultiNodeSpec }
import akka.testkit._
import com.typesafe.config.ConfigFactory
import org.apache.commons.io.FileUtils

import scala.concurrent.duration._

object ClusterShardingRememberEntitiesNewExtractorSpec {

  final case class Started(ref: ActorRef)

  def props(probe: Option[ActorRef]): Props = Props(new TestEntity(probe))

  class TestEntity(probe: Option[ActorRef]) extends Actor with ActorLogging {
    log.info("Entity started: " + self.path)
    probe.foreach(_ ! Started(self))

    def receive = {
      case m ⇒ sender() ! m
    }
  }

  val shardCount = 5

  val extractEntityId: ShardRegion.ExtractEntityId = {
    case id: Int ⇒ (id.toString, id)
  }

  val extractShardId1: ShardRegion.ExtractShardId = {
    case id: Int                     ⇒ (id % shardCount).toString
    case ShardRegion.StartEntity(id) ⇒ extractShardId1(id.toInt)
  }

  val extractShardId2: ShardRegion.ExtractShardId = {
    // always bump it one shard id
    case id: Int                     ⇒ ((id + 1) % shardCount).toString
    case ShardRegion.StartEntity(id) ⇒ extractShardId2(id.toInt)
  }

}

abstract class ClusterShardingRememberEntitiesNewExtractorSpecConfig(val mode: String) extends MultiNodeConfig {
  val first = role("first")
  val second = role("second")
  val third = role("third")
  val fourth = role("fourth")
  val fifth = role("fifth")

  commonConfig(ConfigFactory.parseString(s"""
    akka.loglevel = DEBUG
    akka.actor.provider = "cluster"
    akka.cluster.auto-down-unreachable-after = 0s
    akka.remote.log-remote-lifecycle-events = off
    akka.persistence.journal.plugin = "akka.persistence.journal.leveldb-shared"
    akka.persistence.journal.leveldb-shared {
      timeout = 5s
      store {
        native = off
        dir = "target/ShardingRememberEntitiesNewExtractorSpec/journal"
      }
    }
    akka.persistence.snapshot-store.plugin = "akka.persistence.snapshot-store.local"
    akka.persistence.snapshot-store.local.dir = "target/ShardingRememberEntitiesNewExtractorSpec/snapshots"
    akka.cluster.sharding.state-store-mode = "$mode"
    akka.cluster.sharding.distributed-data.durable.lmdb {
      dir = target/ShardingRememberEntitiesNewExtractorSpec/sharding-ddata
      map-size = 10 MiB
    }
    """))

  val roleConfig = ConfigFactory.parseString(
    """
      akka.cluster.roles = [sharding]
    """)

  // we pretend node 4 and 5 are new incarnations of node 2 and 3 as they never run in parallel
  // so we can use the same lmdb store for them and have node 4 pick up the persisted data of node 2
  val ddataNodeAConfig = ConfigFactory.parseString(
    """
      akka.cluster.sharding.distributed-data.durable.lmdb {
        dir = target/ShardingRememberEntitiesNewExtractorSpec/sharding-node-a
      }
    """)
  val ddataNodeBConfig = ConfigFactory.parseString(
    """
      akka.cluster.sharding.distributed-data.durable.lmdb {
        dir = target/ShardingRememberEntitiesNewExtractorSpec/sharding-node-b
      }
    """)

  nodeConfig(second)(roleConfig.withFallback(ddataNodeAConfig))
  nodeConfig(third)(roleConfig.withFallback(ddataNodeBConfig))
  nodeConfig(fourth)(roleConfig.withFallback(ddataNodeAConfig))
  nodeConfig(fifth)(roleConfig.withFallback(ddataNodeBConfig))

}

object PersistentClusterShardingRememberEntitiesSpecNewExtractorConfig extends ClusterShardingRememberEntitiesNewExtractorSpecConfig(
  ClusterShardingSettings.StateStoreModePersistence)
object DDataClusterShardingRememberEntitiesNewExtractorSpecConfig extends ClusterShardingRememberEntitiesNewExtractorSpecConfig(
  ClusterShardingSettings.StateStoreModeDData)

class PersistentClusterShardingRememberEntitiesNewExtractorSpec extends ClusterShardingRememberEntitiesNewExtractorSpec(
  PersistentClusterShardingRememberEntitiesSpecNewExtractorConfig)

class PersistentClusterShardingRememberEntitiesNewExtractorMultiJvmNode1 extends PersistentClusterShardingRememberEntitiesNewExtractorSpec
class PersistentClusterShardingRememberEntitiesNewExtractorMultiJvmNode2 extends PersistentClusterShardingRememberEntitiesNewExtractorSpec
class PersistentClusterShardingRememberEntitiesNewExtractorMultiJvmNode3 extends PersistentClusterShardingRememberEntitiesNewExtractorSpec
class PersistentClusterShardingRememberEntitiesNewExtractorMultiJvmNode4 extends PersistentClusterShardingRememberEntitiesNewExtractorSpec
class PersistentClusterShardingRememberEntitiesNewExtractorMultiJvmNode5 extends PersistentClusterShardingRememberEntitiesNewExtractorSpec

class DDataClusterShardingRememberEntitiesNewExtractorSpec extends ClusterShardingRememberEntitiesNewExtractorSpec(
  DDataClusterShardingRememberEntitiesNewExtractorSpecConfig)

class DDataClusterShardingRememberEntitiesNewExtractorMultiJvmNode1 extends DDataClusterShardingRememberEntitiesNewExtractorSpec
class DDataClusterShardingRememberEntitiesNewExtractorMultiJvmNode2 extends DDataClusterShardingRememberEntitiesNewExtractorSpec
class DDataClusterShardingRememberEntitiesNewExtractorMultiJvmNode3 extends DDataClusterShardingRememberEntitiesNewExtractorSpec
class DDataClusterShardingRememberEntitiesNewExtractorMultiJvmNode4 extends DDataClusterShardingRememberEntitiesNewExtractorSpec
class DDataClusterShardingRememberEntitiesNewExtractorMultiJvmNode5 extends DDataClusterShardingRememberEntitiesNewExtractorSpec

abstract class ClusterShardingRememberEntitiesNewExtractorSpec(config: ClusterShardingRememberEntitiesNewExtractorSpecConfig) extends MultiNodeSpec(config) with STMultiNodeSpec with ImplicitSender {
  import ClusterShardingRememberEntitiesNewExtractorSpec._
  import config._

  val typeName = "Entity"

  override def initialParticipants = roles.size

  val storageLocations = List(new File(system.settings.config.getString(
    "akka.cluster.sharding.distributed-data.durable.lmdb.dir")).getParentFile)

  override protected def atStartup() {
    storageLocations.foreach(dir ⇒ if (dir.exists) FileUtils.deleteQuietly(dir))
    enterBarrier("startup")
  }

  override protected def afterTermination() {
    storageLocations.foreach(dir ⇒ if (dir.exists) FileUtils.deleteQuietly(dir))
  }

  def join(from: RoleName, to: RoleName): Unit = {
    runOn(from) {
      Cluster(system) join node(to).address
    }
    enterBarrier(from.name + "-joined")
  }

  val cluster = Cluster(system)

  def startShardingWithExtractor1(): Unit = {
    ClusterSharding(system).start(
      typeName = typeName,
      entityProps = ClusterShardingRememberEntitiesNewExtractorSpec.props(None),
      settings = ClusterShardingSettings(system).withRememberEntities(true).withRole("sharding"),
      extractEntityId = extractEntityId,
      extractShardId = extractShardId1)
  }

  def startShardingWithExtractor2(): Unit = {
    ClusterSharding(system).start(
      typeName = typeName,
      entityProps = ClusterShardingRememberEntitiesNewExtractorSpec.props(Some(testActor)),
      settings = ClusterShardingSettings(system).withRememberEntities(true).withRole("sharding"),
      extractEntityId = extractEntityId,
      extractShardId = extractShardId2)
  }

  lazy val region = ClusterSharding(system).shardRegion(typeName)

  def isDdataMode: Boolean = mode == ClusterShardingSettings.StateStoreModeDData

  s"Cluster with min-nr-of-members using sharding ($mode)" must {

    if (!isDdataMode) {
      "setup shared journal" in {
        // start the Persistence extension
        Persistence(system)
        runOn(first) {
          system.actorOf(Props[SharedLeveldbStore], "store")
        }
        enterBarrier("persistence-started")

        runOn(second, third, fourth, fifth) {
          system.actorSelection(node(first) / "user" / "store") ! Identify(None)
          val sharedStore = expectMsgType[ActorIdentity](10.seconds).ref.get
          SharedLeveldbJournal.setStore(sharedStore, system)
        }

        enterBarrier("after-1")
      }
    }

    "start up first cluster and sharding" in within(15.seconds) {
      join(first, first)
      join(second, first)
      join(third, first)

      runOn(first, second, third) {
        within(remaining) {
          awaitAssert {
            cluster.state.members.count(_.status == MemberStatus.Up) should ===(3)
          }
        }
      }
      runOn(second, third) {
        startShardingWithExtractor1()
      }
      enterBarrier("first-cluster-up")

      runOn(second, third) {
        // one entity for each shard id
        (1 to 10).foreach { n ⇒
          region ! n
          expectMsg(n)
        }
      }
      enterBarrier("first-cluster-entities-up")
    }

    "shutdown sharding nodes" in within(30.seconds) {
      runOn(first) {
        testConductor.exit(second, 0).await
        testConductor.exit(third, 0).await
      }
      runOn(first) {
        within(remaining) {
          awaitAssert {
            cluster.state.members.count(_.status == MemberStatus.Up) should ===(1)
          }
        }
      }
      enterBarrier("first-sharding-cluster-stopped")
    }

    "start new nodes with different extractor" in within(15.seconds) {

      // start it with a new shard id extractor, which will put the entities
      // on different shards

      join(fourth, first)
      join(fifth, first)
      runOn(first) {
        within(remaining) {
          awaitAssert {
            cluster.state.members.count(_.status == MemberStatus.Up) should ===(3)
          }
        }
      }
      runOn(fourth, fifth) {
        startShardingWithExtractor2()
      }

      // TODO how do we know that the shards has started??
      Thread.sleep(7000)
      enterBarrier("new-nodes-started")
    }

    "have the remembered entities running on the right shards" in within(15.seconds) {
      runOn(fourth, fifth) {
        var stats: ShardRegion.CurrentShardRegionState = null
        within(remaining) {
          awaitAssert {
            region ! ShardRegion.GetShardRegionState
            val reply = expectMsgType[ShardRegion.CurrentShardRegionState]
            reply.shards should not be empty
            stats = reply
          }
        }

        for {
          shardState ← stats.shards
          entityId ← shardState.entityIds
        } {
          val calculatedShardId = extractShardId2(entityId.toInt)
          calculatedShardId should ===(shardState.shardId)
        }
      }

      enterBarrier("done")
    }

  }
}