content: /*
   * 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 org.apache.kafka.common.requests;
  
  import org.apache.kafka.common.TopicIdPartition;
  import org.apache.kafka.common.TopicPartition;
  import org.apache.kafka.common.Uuid;
  import org.apache.kafka.common.message.ShareFetchRequestData;
  import org.apache.kafka.common.protocol.ApiKeys;
  import org.apache.kafka.common.protocol.Errors;
  import org.apache.kafka.common.protocol.Readable;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  
  public class ShareFetchRequest extends AbstractRequest {
  
      public static class Builder extends AbstractRequest.Builder<ShareFetchRequest> {
  
          private final ShareFetchRequestData data;
  
          public Builder(ShareFetchRequestData data) {
              super(ApiKeys.SHARE_FETCH);
              this.data = data;
          }
  
          public static Builder forConsumer(String groupId, ShareRequestMetadata metadata,
                                            int maxWait, int minBytes, int maxBytes, int maxRecords,
                                            int batchSize, List<TopicIdPartition> send, List<TopicIdPartition> forget,
                                            Map<TopicIdPartition, List<ShareFetchRequestData.AcknowledgementBatch>> acknowledgementsMap) {
              ShareFetchRequestData data = new ShareFetchRequestData();
              data.setGroupId(groupId);
              boolean isClosingShareSession = false;
              if (metadata != null) {
                  data.setMemberId(metadata.memberId().toString());
                  data.setShareSessionEpoch(metadata.epoch());
                  if (metadata.isFinalEpoch()) {
                      isClosingShareSession = true;
                  }
              }
              data.setMaxWaitMs(maxWait);
              data.setMinBytes(minBytes);
              data.setMaxBytes(maxBytes);
              data.setMaxRecords(maxRecords);
              data.setBatchSize(batchSize);
  
              // Build a map of topics to fetch keyed by topic ID, and within each a map of partitions keyed by index
              ShareFetchRequestData.FetchTopicCollection fetchTopics = new ShareFetchRequestData.FetchTopicCollection();
  
              // First, start by adding the list of topic-partitions we are fetching
              if (!isClosingShareSession) {
                  for (TopicIdPartition tip : send) {
                      ShareFetchRequestData.FetchTopic fetchTopic = fetchTopics.find(tip.topicId());
                      if (fetchTopic == null) {
                          fetchTopic = new ShareFetchRequestData.FetchTopic()
                                  .setTopicId(tip.topicId())
                                  .setPartitions(new ShareFetchRequestData.FetchPartitionCollection());
                          fetchTopics.add(fetchTopic);
                      }
                      ShareFetchRequestData.FetchPartition fetchPartition = fetchTopic.partitions().find(tip.partition());
                      if (fetchPartition == null) {
                          fetchPartition = new ShareFetchRequestData.FetchPartition()
                              .setPartitionIndex(tip.partition());
                          fetchTopic.partitions().add(fetchPartition);
                      }
                  }
              }
  
              // Next, add acknowledgements that we are piggybacking onto the fetch. Generally, the list of
              // topic-partitions will be a subset, but if the assignment changes, there might be new entries to add
              for (Map.Entry<TopicIdPartition, List<ShareFetchRequestData.AcknowledgementBatch>> acknowledgeEntry : acknowledgementsMap.entrySet()) {
                  TopicIdPartition tip = acknowledgeEntry.getKey();
                  ShareFetchRequestData.FetchTopic fetchTopic = fetchTopics.find(tip.topicId());
                  if (fetchTopic == null) {
                      fetchTopic = new ShareFetchRequestData.FetchTopic()
                              .setTopicId(tip.topicId())
                              .setPartitions(new ShareFetchRequestData.FetchPartitionCollection());
                      fetchTopics.add(fetchTopic);
                  }
                  ShareFetchRequestData.FetchPartition fetchPartition = fetchTopic.partitions().find(tip.partition());
                  if (fetchPartition == null) {
                      fetchPartition = new ShareFetchRequestData.FetchPartition()
                              .setPartitionIndex(tip.partition());
                      fetchTopic.partitions().add(fetchPartition);
                  }
                  fetchPartition.setAcknowledgementBatches(acknowledgeEntry.getValue());
              }
  
              // Build up the data to fetch
              data.setTopics(fetchTopics);
  
              Builder builder = new Builder(data);
              // And finally, forget the topic-partitions that are no longer in the session
              if (!forget.isEmpty()) {
                  data.setForgottenTopicsData(new ArrayList<>());
                  builder.updateForgottenData(forget);
              }
  
              return builder;
          }
  
          public void updateForgottenData(List<TopicIdPartition> forget) {
              Map<Uuid, List<Integer>> forgetMap = new HashMap<>();
              for (TopicIdPartition tip : forget) {
                  List<Integer> partList = forgetMap.computeIfAbsent(tip.topicId(), k -> new ArrayList<>());
                  partList.add(tip.partition());
              }
              forgetMap.forEach((topicId, partList) -> {
                  ShareFetchRequestData.ForgottenTopic forgetTopic = new ShareFetchRequestData.ForgottenTopic()
                          .setTopicId(topicId)
                          .setPartitions(new ArrayList<>());
                  partList.forEach(index -> forgetTopic.partitions().add(index));
                  data.forgottenTopicsData().add(forgetTopic);
              });
          }
  
          public ShareFetchRequestData data() {
              return data;
          }
  
          @Override
          public ShareFetchRequest build(short version) {
              return new ShareFetchRequest(data, version);
          }
  
          @Override
          public String toString() {
              return data.toString();
          }
      }
  
      private final ShareFetchRequestData data;
      private volatile List<TopicIdPartition> shareFetchData = null;
      private volatile List<TopicIdPartition> toForget = null;
  
      public ShareFetchRequest(ShareFetchRequestData data, short version) {
          super(ApiKeys.SHARE_FETCH, version);
          this.data = data;
      }
  
      @Override
      public ShareFetchRequestData data() {
          return data;
      }
  
      @Override
      public AbstractResponse getErrorResponse(int throttleTimeMs, Throwable e) {
          Errors error = Errors.forException(e);
          return ShareFetchResponse.of(error, throttleTimeMs, new LinkedHashMap<>(), List.of(), 0);
      }
  
      public static ShareFetchRequest parse(Readable readable, short version) {
          return new ShareFetchRequest(
                  new ShareFetchRequestData(readable, version),
                  version
          );
      }
  
      public int minBytes() {
          return data.minBytes();
      }
  
      public int maxBytes() {
          return data.maxBytes();
      }
  
      public int maxWait() {
          return data.maxWaitMs();
      }
  
      public List<TopicIdPartition> shareFetchData(Map<Uuid, String> topicNames) {
          if (shareFetchData == null) {
              synchronized (this) {
                  if (shareFetchData == null) {
                      // Assigning the lazy-initialized `shareFetchData` in the last step
                      // to avoid other threads accessing a half-initialized object.
                      final List<TopicIdPartition> shareFetchDataTmp = new ArrayList<>();
                      data.topics().forEach(shareFetchTopic -> {
                          String name = topicNames.get(shareFetchTopic.topicId());
                          shareFetchTopic.partitions().forEach(shareFetchPartition -> {
                              // Topic name may be null here if the topic name was unable to be resolved using the topicNames map.
                              shareFetchDataTmp.add(new TopicIdPartition(shareFetchTopic.topicId(), shareFetchPartition.partitionIndex(), name));
                          });
                      });
                      shareFetchData = shareFetchDataTmp;
                  }
              }
          }
          return shareFetchData;
      }
  
      public List<TopicIdPartition> forgottenTopics(Map<Uuid, String> topicNames) {
          if (toForget == null) {
              synchronized (this) {
                  if (toForget == null) {
                      // Assigning the lazy-initialized `toForget` in the last step
                      // to avoid other threads accessing a half-initialized object.
                      final List<TopicIdPartition> toForgetTmp = new ArrayList<>();
                      data.forgottenTopicsData().forEach(forgottenTopic -> {
                          String name = topicNames.get(forgottenTopic.topicId());
                          // Topic name may be null here if the topic name was unable to be resolved using the topicNames map.
                          forgottenTopic.partitions().forEach(partitionId -> toForgetTmp.add(new TopicIdPartition(forgottenTopic.topicId(), new TopicPartition(name, partitionId))));
                      });
                      toForget = toForgetTmp;
                  }
              }
          }
          return toForget;
      }
  }