/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package kafka.admin

import java.util
import java.util.{Collections, Properties}
import joptsimple._
import kafka.common.AdminCommandFailedException
import kafka.log.LogConfig
import kafka.utils._
import org.apache.kafka.clients.CommonClientConfigs
import org.apache.kafka.clients.admin.CreatePartitionsOptions
import org.apache.kafka.clients.admin.CreateTopicsOptions
import org.apache.kafka.clients.admin.DeleteTopicsOptions
import org.apache.kafka.clients.admin.{Admin, ListTopicsOptions, NewPartitions, NewTopic, PartitionReassignment, Config => JConfig}
import org.apache.kafka.common.{TopicPartition, TopicPartitionInfo, Uuid}
import org.apache.kafka.common.config.ConfigResource.Type
import org.apache.kafka.common.config.{ConfigResource, TopicConfig}
import org.apache.kafka.common.errors.{ClusterAuthorizationException, TopicExistsException, UnsupportedVersionException}
import org.apache.kafka.common.internals.Topic
import org.apache.kafka.common.utils.Utils

import scala.annotation.nowarn
import scala.jdk.CollectionConverters._
import scala.collection._
import scala.compat.java8.OptionConverters._
import scala.concurrent.ExecutionException

object TopicCommand extends Logging {

  def main(args: Array[String]): Unit = {
    val opts = new TopicCommandOptions(args)
    opts.checkArgs()

    val topicService = TopicService(opts.commandConfig, opts.bootstrapServer)

    var exitCode = 0
    try {
      if (opts.hasCreateOption)
        topicService.createTopic(opts)
      else if (opts.hasAlterOption)
        topicService.alterTopic(opts)
      else if (opts.hasListOption)
        topicService.listTopics(opts)
      else if (opts.hasDescribeOption)
        topicService.describeTopic(opts)
      else if (opts.hasDeleteOption)
        topicService.deleteTopic(opts)
    } catch {
      case e: ExecutionException =>
        if (e.getCause != null)
          printException(e.getCause)
        else
          printException(e)
        exitCode = 1
      case e: Throwable =>
        printException(e)
        exitCode = 1
    } finally {
      topicService.close()
      Exit.exit(exitCode)
    }
  }

  private def printException(e: Throwable): Unit = {
    println("Error while executing topic command : " + e.getMessage)
    error(Utils.stackTrace(e))
  }

  class CommandTopicPartition(opts: TopicCommandOptions) {
    val name = opts.topic.get
    val partitions = opts.partitions
    val replicationFactor = opts.replicationFactor
    val replicaAssignment = opts.replicaAssignment
    val configsToAdd = parseTopicConfigsToBeAdded(opts)
    val configsToDelete = parseTopicConfigsToBeDeleted(opts)
    val rackAwareMode = opts.rackAwareMode

    def hasReplicaAssignment: Boolean = replicaAssignment.isDefined
    def hasPartitions: Boolean = partitions.isDefined
    def ifTopicDoesntExist(): Boolean = opts.ifNotExists
  }

  case class TopicDescription(topic: String,
                              topicId: Uuid,
                              numPartitions: Int,
                              replicationFactor: Int,
                              config: JConfig,
                              markedForDeletion: Boolean) {

    def printDescription(): Unit = {
      val configsAsString = config.entries.asScala.filter(!_.isDefault).map { ce => s"${ce.name}=${ce.value}" }.mkString(",")
      print(s"Topic: $topic")
      if(topicId != Uuid.ZERO_UUID) print(s"\tTopicId: $topicId")
      print(s"\tPartitionCount: $numPartitions")
      print(s"\tReplicationFactor: $replicationFactor")
      print(s"\tConfigs: $configsAsString")
      print(if (markedForDeletion) "\tMarkedForDeletion: true" else "")
      println()
    }
  }

  case class PartitionDescription(topic: String,
                                  info: TopicPartitionInfo,
                                  config: Option[JConfig],
                                  markedForDeletion: Boolean,
                                  reassignment: Option[PartitionReassignment]) {

    private def minIsrCount: Option[Int] = {
      config.map(_.get(TopicConfig.MIN_IN_SYNC_REPLICAS_CONFIG).value.toInt)
    }

    def isUnderReplicated: Boolean = {
      getReplicationFactor(info, reassignment) - info.isr.size > 0
    }

    private def hasLeader: Boolean = {
      info.leader != null
    }

    def isUnderMinIsr: Boolean = {
      !hasLeader || minIsrCount.exists(info.isr.size < _)
    }

    def isAtMinIsrPartitions: Boolean =  {
      minIsrCount.contains(info.isr.size)
    }

    def hasUnavailablePartitions(liveBrokers: Set[Int]): Boolean = {
      !hasLeader || !liveBrokers.contains(info.leader.id)
    }

    def printDescription(): Unit = {
      print("\tTopic: " + topic)
      print("\tPartition: " + info.partition)
      print("\tLeader: " + (if (hasLeader) info.leader.id else "none"))
      print("\tReplicas: " + info.replicas.asScala.map(_.id).mkString(","))
      print("\tIsr: " + info.isr.asScala.map(_.id).mkString(","))
      if (reassignment.nonEmpty) {
        print("\tAdding Replicas: " + reassignment.get.addingReplicas().asScala.mkString(","))
        print("\tRemoving Replicas: " + reassignment.get.removingReplicas().asScala.mkString(","))
      }
      print(if (markedForDeletion) "\tMarkedForDeletion: true" else "")
      println()
    }

  }

  class DescribeOptions(opts: TopicCommandOptions, liveBrokers: Set[Int]) {
    val describeConfigs =
      !opts.reportUnavailablePartitions &&
      !opts.reportUnderReplicatedPartitions &&
      !opts.reportUnderMinIsrPartitions &&
      !opts.reportAtMinIsrPartitions
    val describePartitions = !opts.reportOverriddenConfigs

    private def shouldPrintUnderReplicatedPartitions(partitionDescription: PartitionDescription): Boolean = {
      opts.reportUnderReplicatedPartitions && partitionDescription.isUnderReplicated
    }
    private def shouldPrintUnavailablePartitions(partitionDescription: PartitionDescription): Boolean = {
      opts.reportUnavailablePartitions && partitionDescription.hasUnavailablePartitions(liveBrokers)
    }
    private def shouldPrintUnderMinIsrPartitions(partitionDescription: PartitionDescription): Boolean = {
      opts.reportUnderMinIsrPartitions && partitionDescription.isUnderMinIsr
    }
    private def shouldPrintAtMinIsrPartitions(partitionDescription: PartitionDescription): Boolean = {
      opts.reportAtMinIsrPartitions && partitionDescription.isAtMinIsrPartitions
    }

    private def shouldPrintTopicPartition(partitionDesc: PartitionDescription): Boolean = {
      describeConfigs ||
        shouldPrintUnderReplicatedPartitions(partitionDesc) ||
        shouldPrintUnavailablePartitions(partitionDesc) ||
        shouldPrintUnderMinIsrPartitions(partitionDesc) ||
        shouldPrintAtMinIsrPartitions(partitionDesc)
    }

    def maybePrintPartitionDescription(desc: PartitionDescription): Unit = {
      if (shouldPrintTopicPartition(desc))
        desc.printDescription()
    }
  }

  object TopicService {
    def createAdminClient(commandConfig: Properties, bootstrapServer: Option[String]): Admin = {
      bootstrapServer match {
        case Some(serverList) => commandConfig.put(CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG, serverList)
        case None =>
      }
      Admin.create(commandConfig)
    }

    def apply(commandConfig: Properties, bootstrapServer: Option[String]): TopicService =
      new TopicService(createAdminClient(commandConfig, bootstrapServer))
  }

  case class TopicService private (adminClient: Admin) extends AutoCloseable {

    def createTopic(opts: TopicCommandOptions): Unit = {
      val topic = new CommandTopicPartition(opts)
      if (Topic.hasCollisionChars(topic.name))
        println("WARNING: Due to limitations in metric names, topics with a period ('.') or underscore ('_') could " +
          "collide. To avoid issues it is best to use either, but not both.")
      createTopic(topic)
    }

    def createTopic(topic: CommandTopicPartition): Unit = {
      if (topic.replicationFactor.exists(rf => rf > Short.MaxValue || rf < 1))
        throw new IllegalArgumentException(s"The replication factor must be between 1 and ${Short.MaxValue} inclusive")
      if (topic.partitions.exists(partitions => partitions < 1))
        throw new IllegalArgumentException(s"The partitions must be greater than 0")

      try {
        val newTopic = if (topic.hasReplicaAssignment)
          new NewTopic(topic.name, asJavaReplicaReassignment(topic.replicaAssignment.get))
        else {
          new NewTopic(
            topic.name,
            topic.partitions.asJava,
            topic.replicationFactor.map(_.toShort).map(Short.box).asJava)
        }

        val configsMap = topic.configsToAdd.stringPropertyNames()
          .asScala
          .map(name => name -> topic.configsToAdd.getProperty(name))
          .toMap.asJava

        newTopic.configs(configsMap)
        val createResult = adminClient.createTopics(Collections.singleton(newTopic),
          new CreateTopicsOptions().retryOnQuotaViolation(false))
        createResult.all().get()
        println(s"Created topic ${topic.name}.")
      } catch {
        case e : ExecutionException =>
          if (e.getCause == null)
            throw e
          if (!(e.getCause.isInstanceOf[TopicExistsException] && topic.ifTopicDoesntExist()))
            throw e.getCause
      }
    }

    def listTopics(opts: TopicCommandOptions): Unit = {
      println(getTopics(opts.topic, opts.excludeInternalTopics).mkString("\n"))
    }

    def alterTopic(opts: TopicCommandOptions): Unit = {
      val topic = new CommandTopicPartition(opts)
      val topics = getTopics(opts.topic, opts.excludeInternalTopics)
      ensureTopicExists(topics, opts.topic, !opts.ifExists)

      if (topics.nonEmpty) {
        val topicsInfo = adminClient.describeTopics(topics.asJavaCollection).values()
        val newPartitions = topics.map { topicName =>
          if (topic.hasReplicaAssignment) {
            val startPartitionId = topicsInfo.get(topicName).get().partitions().size()
            val newAssignment = {
              val replicaMap = topic.replicaAssignment.get.drop(startPartitionId)
              new util.ArrayList(replicaMap.map(p => p._2.asJava).asJavaCollection).asInstanceOf[util.List[util.List[Integer]]]
            }
            topicName -> NewPartitions.increaseTo(topic.partitions.get, newAssignment)
          } else {
            topicName -> NewPartitions.increaseTo(topic.partitions.get)
          }
        }.toMap
        adminClient.createPartitions(newPartitions.asJava,
          new CreatePartitionsOptions().retryOnQuotaViolation(false)).all().get()
      }
    }

    def listAllReassignments(topicPartitions: util.Set[TopicPartition]): Map[TopicPartition, PartitionReassignment] = {
      try {
        adminClient.listPartitionReassignments(topicPartitions).reassignments().get().asScala
      } catch {
        case e: ExecutionException =>
          e.getCause match {
            case ex @ (_: UnsupportedVersionException | _: ClusterAuthorizationException) =>
              logger.debug(s"Couldn't query reassignments through the AdminClient API: ${ex.getMessage}", ex)
              Map()
            case t => throw t
          }
      }
    }

    def describeTopic(opts: TopicCommandOptions): Unit = {
      val topics = getTopics(opts.topic, opts.excludeInternalTopics)
      ensureTopicExists(topics, opts.topic, !opts.ifExists)

      if (topics.nonEmpty) {
        val allConfigs = adminClient.describeConfigs(topics.map(new ConfigResource(Type.TOPIC, _)).asJavaCollection).values()
        val liveBrokers = adminClient.describeCluster().nodes().get().asScala.map(_.id())
        val topicDescriptions = adminClient.describeTopics(topics.asJavaCollection).all().get().values().asScala
        val describeOptions = new DescribeOptions(opts, liveBrokers.toSet)
        val topicPartitions = topicDescriptions
          .flatMap(td => td.partitions.iterator().asScala.map(p => new TopicPartition(td.name(), p.partition())))
          .toSet.asJava
        val reassignments = listAllReassignments(topicPartitions)

        for (td <- topicDescriptions) {
          val topicName = td.name
          val topicId = td.topicId()
          val config = allConfigs.get(new ConfigResource(Type.TOPIC, topicName)).get()
          val sortedPartitions = td.partitions.asScala.sortBy(_.partition)

          if (describeOptions.describeConfigs) {
            val hasNonDefault = config.entries().asScala.exists(!_.isDefault)
            if (!opts.reportOverriddenConfigs || hasNonDefault) {
              val numPartitions = td.partitions().size
              val firstPartition = td.partitions.iterator.next()
              val reassignment = reassignments.get(new TopicPartition(td.name, firstPartition.partition))
              val topicDesc = TopicDescription(topicName, topicId, numPartitions, getReplicationFactor(firstPartition, reassignment), config, markedForDeletion = false)
              topicDesc.printDescription()
            }
          }

          if (describeOptions.describePartitions) {
            for (partition <- sortedPartitions) {
              val reassignment = reassignments.get(new TopicPartition(td.name, partition.partition))
              val partitionDesc = PartitionDescription(topicName, partition, Some(config), markedForDeletion = false, reassignment)
              describeOptions.maybePrintPartitionDescription(partitionDesc)
            }
          }
        }
      }
    }

    def deleteTopic(opts: TopicCommandOptions): Unit = {
      val topics = getTopics(opts.topic, opts.excludeInternalTopics)
      ensureTopicExists(topics, opts.topic, !opts.ifExists)
      adminClient.deleteTopics(topics.asJavaCollection, new DeleteTopicsOptions().retryOnQuotaViolation(false))
        .all().get()
    }

    def getTopics(topicIncludelist: Option[String], excludeInternalTopics: Boolean = false): Seq[String] = {
      val allTopics = if (excludeInternalTopics) {
        adminClient.listTopics()
      } else {
        adminClient.listTopics(new ListTopicsOptions().listInternal(true))
      }
      doGetTopics(allTopics.names().get().asScala.toSeq.sorted, topicIncludelist, excludeInternalTopics)
    }

    def close(): Unit = adminClient.close()
  }

  /**
    * ensures topic existence and throws exception if topic doesn't exist
    *
    * @param foundTopics Topics that were found to match the requested topic name.
    * @param requestedTopic Name of the topic that was requested.
    * @param requireTopicExists Indicates if the topic needs to exist for the operation to be successful.
    *                           If set to true, the command will throw an exception if the topic with the
    *                           requested name does not exist.
    */
  private def ensureTopicExists(foundTopics: Seq[String], requestedTopic: Option[String], requireTopicExists: Boolean): Unit = {
    // If no topic name was mentioned, do not need to throw exception.
    if (requestedTopic.isDefined && requireTopicExists && foundTopics.isEmpty) {
      // If given topic doesn't exist then throw exception
      throw new IllegalArgumentException(s"Topic '${requestedTopic.get}' does not exist as expected")
    }
  }

  private def doGetTopics(allTopics: Seq[String], topicIncludeList: Option[String], excludeInternalTopics: Boolean): Seq[String] = {
    if (topicIncludeList.isDefined) {
      val topicsFilter = IncludeList(topicIncludeList.get)
      allTopics.filter(topicsFilter.isTopicAllowed(_, excludeInternalTopics))
    } else
    allTopics.filterNot(Topic.isInternal(_) && excludeInternalTopics)
  }

  @nowarn("cat=deprecation")
  def parseTopicConfigsToBeAdded(opts: TopicCommandOptions): Properties = {
    val configsToBeAdded = opts.topicConfig.getOrElse(Collections.emptyList()).asScala.map(_.split("""\s*=\s*"""))
    require(configsToBeAdded.forall(config => config.length == 2),
      "Invalid topic config: all configs to be added must be in the format \"key=val\".")
    val props = new Properties
    configsToBeAdded.foreach(pair => props.setProperty(pair(0).trim, pair(1).trim))
    LogConfig.validate(props)
    if (props.containsKey(LogConfig.MessageFormatVersionProp)) {
      println(s"WARNING: The configuration ${LogConfig.MessageFormatVersionProp}=${props.getProperty(LogConfig.MessageFormatVersionProp)} is specified. " +
        "This configuration will be ignored if the version is newer than the inter.broker.protocol.version specified in the broker or " +
        "if the inter.broker.protocol.version is 3.0 or newer. This configuration is deprecated and it will be removed in Apache Kafka 4.0.")
    }
    props
  }

  def parseTopicConfigsToBeDeleted(opts: TopicCommandOptions): Seq[String] = {
    val configsToBeDeleted = opts.configsToDelete.getOrElse(Collections.emptyList()).asScala.map(_.trim())
    val propsToBeDeleted = new Properties
    configsToBeDeleted.foreach(propsToBeDeleted.setProperty(_, ""))
    LogConfig.validateNames(propsToBeDeleted)
    configsToBeDeleted
  }

  def parseReplicaAssignment(replicaAssignmentList: String): Map[Int, List[Int]] = {
    val partitionList = replicaAssignmentList.split(",")
    val ret = new mutable.LinkedHashMap[Int, List[Int]]()
    for (i <- 0 until partitionList.size) {
      val brokerList = partitionList(i).split(":").map(s => s.trim().toInt)
      val duplicateBrokers = CoreUtils.duplicates(brokerList)
      if (duplicateBrokers.nonEmpty)
        throw new AdminCommandFailedException(s"Partition replica lists may not contain duplicate entries: ${duplicateBrokers.mkString(",")}")
      ret.put(i, brokerList.toList)
      if (ret(i).size != ret(0).size)
        throw new AdminOperationException("Partition " + i + " has different replication factor: " + brokerList)
    }
    ret
  }

  def asJavaReplicaReassignment(original: Map[Int, List[Int]]): util.Map[Integer, util.List[Integer]] = {
    original.map(f => Integer.valueOf(f._1) -> f._2.map(e => Integer.valueOf(e)).asJava).asJava
  }

  private def getReplicationFactor(tpi: TopicPartitionInfo, reassignment: Option[PartitionReassignment]): Int = {
    // It is possible for a reassignment to complete between the time we have fetched its state and the time
    // we fetch partition metadata. In ths case, we ignore the reassignment when determining replication factor.
    def isReassignmentInProgress(ra: PartitionReassignment): Boolean = {
      // Reassignment is still in progress as long as the removing and adding replicas are still present
      val allReplicaIds = tpi.replicas.asScala.map(_.id).toSet
      val changingReplicaIds = ra.removingReplicas.asScala.map(_.intValue).toSet ++ ra.addingReplicas.asScala.map(_.intValue).toSet
      allReplicaIds.exists(changingReplicaIds.contains)
    }

    reassignment match {
      case Some(ra) if isReassignmentInProgress(ra) => ra.replicas.asScala.diff(ra.addingReplicas.asScala).size
      case _=> tpi.replicas.size
    }
  }

  class TopicCommandOptions(args: Array[String]) extends CommandDefaultOptions(args) {
    private val bootstrapServerOpt = parser.accepts("bootstrap-server", "REQUIRED: The Kafka server to connect to.")
      .withRequiredArg
      .describedAs("server to connect to")
      .ofType(classOf[String])

    private val commandConfigOpt = parser.accepts("command-config", "Property file containing configs to be passed to Admin Client. " +
      "This is used only with --bootstrap-server option for describing and altering broker configs.")
      .withRequiredArg
      .describedAs("command config property file")
      .ofType(classOf[String])

    private val listOpt = parser.accepts("list", "List all available topics.")
    private val createOpt = parser.accepts("create", "Create a new topic.")
    private val deleteOpt = parser.accepts("delete", "Delete a topic")
    private val alterOpt = parser.accepts("alter", "Alter the number of partitions, replica assignment, and/or configuration for the topic.")
    private val describeOpt = parser.accepts("describe", "List details for the given topics.")
    private val topicOpt = parser.accepts("topic", "The topic to create, alter, describe or delete. It also accepts a regular " +
                                           "expression, except for --create option. Put topic name in double quotes and use the '\\' prefix " +
                                           "to escape regular expression symbols; e.g. \"test\\.topic\".")
                         .withRequiredArg
                         .describedAs("topic")
                         .ofType(classOf[String])
    private val nl = System.getProperty("line.separator")
    private val kafkaConfigsCanAlterTopicConfigsViaBootstrapServer =
      " (the kafka-configs CLI supports altering topic configs with a --bootstrap-server option)"
    private val configOpt = parser.accepts("config", "A topic configuration override for the topic being created or altered." +
                                             " The following is a list of valid configurations: " + nl + LogConfig.configNames.map("\t" + _).mkString(nl) + nl +
                                             "See the Kafka documentation for full details on the topic configs." +
                                             " It is supported only in combination with --create if --bootstrap-server option is used" +
                                             kafkaConfigsCanAlterTopicConfigsViaBootstrapServer + ".")
                           .withRequiredArg
                           .describedAs("name=value")
                           .ofType(classOf[String])
    private val deleteConfigOpt = parser.accepts("delete-config", "A topic configuration override to be removed for an existing topic (see the list of configurations under the --config option). " +
      "Not supported with the --bootstrap-server option.")
                           .withRequiredArg
                           .describedAs("name")
                           .ofType(classOf[String])
    private val partitionsOpt = parser.accepts("partitions", "The number of partitions for the topic being created or " +
      "altered (WARNING: If partitions are increased for a topic that has a key, the partition logic or ordering of the messages will be affected). If not supplied for create, defaults to the cluster default.")
                           .withRequiredArg
                           .describedAs("# of partitions")
                           .ofType(classOf[java.lang.Integer])
    private val replicationFactorOpt = parser.accepts("replication-factor", "The replication factor for each partition in the topic being created. If not supplied, defaults to the cluster default.")
                           .withRequiredArg
                           .describedAs("replication factor")
                           .ofType(classOf[java.lang.Integer])
    private val replicaAssignmentOpt = parser.accepts("replica-assignment", "A list of manual partition-to-broker assignments for the topic being created or altered.")
                           .withRequiredArg
                           .describedAs("broker_id_for_part1_replica1 : broker_id_for_part1_replica2 , " +
                                        "broker_id_for_part2_replica1 : broker_id_for_part2_replica2 , ...")
                           .ofType(classOf[String])
    private val reportUnderReplicatedPartitionsOpt = parser.accepts("under-replicated-partitions",
      "if set when describing topics, only show under replicated partitions")
    private val reportUnavailablePartitionsOpt = parser.accepts("unavailable-partitions",
      "if set when describing topics, only show partitions whose leader is not available")
    private val reportUnderMinIsrPartitionsOpt = parser.accepts("under-min-isr-partitions",
      "if set when describing topics, only show partitions whose isr count is less than the configured minimum.")
    private val reportAtMinIsrPartitionsOpt = parser.accepts("at-min-isr-partitions",
      "if set when describing topics, only show partitions whose isr count is equal to the configured minimum.")
    private val topicsWithOverridesOpt = parser.accepts("topics-with-overrides",
      "if set when describing topics, only show topics that have overridden configs")
    private val ifExistsOpt = parser.accepts("if-exists",
      "if set when altering or deleting or describing topics, the action will only execute if the topic exists.")
    private val ifNotExistsOpt = parser.accepts("if-not-exists",
      "if set when creating topics, the action will only execute if the topic does not already exist.")

    private val disableRackAware = parser.accepts("disable-rack-aware", "Disable rack aware replica assignment")

    private val excludeInternalTopicOpt = parser.accepts("exclude-internal",
      "exclude internal topics when running list or describe command. The internal topics will be listed by default")

    options = parser.parse(args : _*)

    private val allTopicLevelOpts = immutable.Set[OptionSpec[_]](alterOpt, createOpt, describeOpt, listOpt, deleteOpt)

    private val allReplicationReportOpts = Set(reportUnderReplicatedPartitionsOpt, reportUnderMinIsrPartitionsOpt, reportAtMinIsrPartitionsOpt, reportUnavailablePartitionsOpt)

    def has(builder: OptionSpec[_]): Boolean = options.has(builder)
    def valueAsOption[A](option: OptionSpec[A], defaultValue: Option[A] = None): Option[A] = if (has(option)) Some(options.valueOf(option)) else defaultValue
    def valuesAsOption[A](option: OptionSpec[A], defaultValue: Option[util.List[A]] = None): Option[util.List[A]] = if (has(option)) Some(options.valuesOf(option)) else defaultValue

    def hasCreateOption: Boolean = has(createOpt)
    def hasAlterOption: Boolean = has(alterOpt)
    def hasListOption: Boolean = has(listOpt)
    def hasDescribeOption: Boolean = has(describeOpt)
    def hasDeleteOption: Boolean = has(deleteOpt)

    def bootstrapServer: Option[String] = valueAsOption(bootstrapServerOpt)
    def commandConfig: Properties = if (has(commandConfigOpt)) Utils.loadProps(options.valueOf(commandConfigOpt)) else new Properties()
    def topic: Option[String] = valueAsOption(topicOpt)
    def partitions: Option[Integer] = valueAsOption(partitionsOpt)
    def replicationFactor: Option[Integer] = valueAsOption(replicationFactorOpt)
    def replicaAssignment: Option[Map[Int, List[Int]]] =
      if (has(replicaAssignmentOpt) && !Option(options.valueOf(replicaAssignmentOpt)).getOrElse("").isEmpty)
        Some(parseReplicaAssignment(options.valueOf(replicaAssignmentOpt)))
      else
        None
    def rackAwareMode: RackAwareMode = if (has(disableRackAware)) RackAwareMode.Disabled else RackAwareMode.Enforced
    def reportUnderReplicatedPartitions: Boolean = has(reportUnderReplicatedPartitionsOpt)
    def reportUnavailablePartitions: Boolean = has(reportUnavailablePartitionsOpt)
    def reportUnderMinIsrPartitions: Boolean = has(reportUnderMinIsrPartitionsOpt)
    def reportAtMinIsrPartitions: Boolean = has(reportAtMinIsrPartitionsOpt)
    def reportOverriddenConfigs: Boolean = has(topicsWithOverridesOpt)
    def ifExists: Boolean = has(ifExistsOpt)
    def ifNotExists: Boolean = has(ifNotExistsOpt)
    def excludeInternalTopics: Boolean = has(excludeInternalTopicOpt)
    def topicConfig: Option[util.List[String]] = valuesAsOption(configOpt)
    def configsToDelete: Option[util.List[String]] = valuesAsOption(deleteConfigOpt)

    def checkArgs(): Unit = {
      if (args.length == 0)
        CommandLineUtils.printUsageAndDie(parser, "Create, delete, describe, or change a topic.")

      CommandLineUtils.printHelpAndExitIfNeeded(this, "This tool helps to create, delete, describe, or change a topic.")

      // should have exactly one action
      val actions = Seq(createOpt, listOpt, alterOpt, describeOpt, deleteOpt).count(options.has)
      if (actions != 1)
        CommandLineUtils.printUsageAndDie(parser, "Command must include exactly one action: --list, --describe, --create, --alter or --delete")

      // check required args
      if (!has(bootstrapServerOpt))
        throw new IllegalArgumentException("--bootstrap-server must be specified")
      if (has(describeOpt) && has(ifExistsOpt))
        CommandLineUtils.checkRequiredArgs(parser, options, topicOpt)
      if (!has(listOpt) && !has(describeOpt))
        CommandLineUtils.checkRequiredArgs(parser, options, topicOpt)
      if (has(alterOpt)) {
        CommandLineUtils.checkInvalidArgsSet(parser, options, Set(bootstrapServerOpt, configOpt), Set(alterOpt),
        Some(kafkaConfigsCanAlterTopicConfigsViaBootstrapServer))
        CommandLineUtils.checkRequiredArgs(parser, options, partitionsOpt)
      }

      // check invalid args
      CommandLineUtils.checkInvalidArgs(parser, options, configOpt, allTopicLevelOpts -- Set(alterOpt, createOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, deleteConfigOpt, allTopicLevelOpts -- Set(alterOpt) ++ Set(bootstrapServerOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, partitionsOpt, allTopicLevelOpts -- Set(alterOpt, createOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, replicationFactorOpt, allTopicLevelOpts -- Set(createOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, replicaAssignmentOpt, allTopicLevelOpts -- Set(createOpt,alterOpt))
      if(options.has(createOpt))
        CommandLineUtils.checkInvalidArgs(parser, options, replicaAssignmentOpt, Set(partitionsOpt, replicationFactorOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, reportUnderReplicatedPartitionsOpt,
        allTopicLevelOpts -- Set(describeOpt) ++ allReplicationReportOpts - reportUnderReplicatedPartitionsOpt + topicsWithOverridesOpt)
      CommandLineUtils.checkInvalidArgs(parser, options, reportUnderMinIsrPartitionsOpt,
        allTopicLevelOpts -- Set(describeOpt) ++ allReplicationReportOpts - reportUnderMinIsrPartitionsOpt + topicsWithOverridesOpt)
      CommandLineUtils.checkInvalidArgs(parser, options, reportAtMinIsrPartitionsOpt,
        allTopicLevelOpts -- Set(describeOpt) ++ allReplicationReportOpts - reportAtMinIsrPartitionsOpt + topicsWithOverridesOpt)
      CommandLineUtils.checkInvalidArgs(parser, options, reportUnavailablePartitionsOpt,
        allTopicLevelOpts -- Set(describeOpt) ++ allReplicationReportOpts - reportUnavailablePartitionsOpt + topicsWithOverridesOpt)
      CommandLineUtils.checkInvalidArgs(parser, options, topicsWithOverridesOpt,
        allTopicLevelOpts -- Set(describeOpt) ++ allReplicationReportOpts)
      CommandLineUtils.checkInvalidArgs(parser, options, ifExistsOpt, allTopicLevelOpts -- Set(alterOpt, deleteOpt, describeOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, ifNotExistsOpt, allTopicLevelOpts -- Set(createOpt))
      CommandLineUtils.checkInvalidArgs(parser, options, excludeInternalTopicOpt, allTopicLevelOpts -- Set(listOpt, describeOpt))
    }
  }
}

