content: /*
   * Copyright 2014-2025 Real Logic Limited.
   *
   * Licensed 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
   *
   * https://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 io.aeron.cluster.service;
  
  import io.aeron.FragmentAssembler;
  import io.aeron.Subscription;
  import io.aeron.cluster.client.ClusterException;
  import io.aeron.cluster.codecs.*;
  import io.aeron.logbuffer.Header;
  import org.agrona.CloseHelper;
  import org.agrona.DirectBuffer;
  
  final class ServiceAdapter implements AutoCloseable
  {
      private static final int FRAGMENT_LIMIT = 1;
  
      private final Subscription subscription;
      private final ClusteredServiceAgent clusteredServiceAgent;
      private final FragmentAssembler fragmentAssembler = new FragmentAssembler(this::onFragment);
  
      private final MessageHeaderDecoder messageHeaderDecoder = new MessageHeaderDecoder();
      private final JoinLogDecoder joinLogDecoder = new JoinLogDecoder();
      private final RequestServiceAckDecoder requestServiceAckDecoder = new RequestServiceAckDecoder();
      private final ServiceTerminationPositionDecoder serviceTerminationPositionDecoder =
          new ServiceTerminationPositionDecoder();
  
      ServiceAdapter(final Subscription subscription, final ClusteredServiceAgent clusteredServiceAgent)
      {
          this.subscription = subscription;
          this.clusteredServiceAgent = clusteredServiceAgent;
      }
  
      public void close()
      {
          CloseHelper.close(subscription);
      }
  
      int poll()
      {
          return subscription.poll(fragmentAssembler, FRAGMENT_LIMIT);
      }
  
      private void onFragment(final DirectBuffer buffer, final int offset, final int length, final Header header)
      {
          messageHeaderDecoder.wrap(buffer, offset);
  
          final int schemaId = messageHeaderDecoder.schemaId();
          if (schemaId != MessageHeaderDecoder.SCHEMA_ID)
          {
              throw new ClusterException("expected schemaId=" + MessageHeaderDecoder.SCHEMA_ID + ", actual=" + schemaId);
          }
  
          switch (messageHeaderDecoder.templateId())
          {
              case JoinLogDecoder.TEMPLATE_ID:
                  joinLogDecoder.wrap(
                      buffer,
                      offset + MessageHeaderDecoder.ENCODED_LENGTH,
                      messageHeaderDecoder.blockLength(),
                      messageHeaderDecoder.version());
  
                  clusteredServiceAgent.onJoinLog(
                      joinLogDecoder.logPosition(),
                      joinLogDecoder.maxLogPosition(),
                      joinLogDecoder.memberId(),
                      joinLogDecoder.logSessionId(),
                      joinLogDecoder.logStreamId(),
                      joinLogDecoder.isStartup() == BooleanType.TRUE,
                      Cluster.Role.get(joinLogDecoder.role()),
                      joinLogDecoder.logChannel());
                  break;
  
              case ServiceTerminationPositionDecoder.TEMPLATE_ID:
                  serviceTerminationPositionDecoder.wrap(
                      buffer,
                      offset + MessageHeaderDecoder.ENCODED_LENGTH,
                      messageHeaderDecoder.blockLength(),
                      messageHeaderDecoder.version());
  
                  clusteredServiceAgent.onServiceTerminationPosition(serviceTerminationPositionDecoder.logPosition());
                  break;
  
              case RequestServiceAckDecoder.TEMPLATE_ID:
                  requestServiceAckDecoder.wrap(
                      buffer,
                      offset + MessageHeaderDecoder.ENCODED_LENGTH,
                      messageHeaderDecoder.blockLength(),
                      messageHeaderDecoder.version());
  
                  clusteredServiceAgent.onRequestServiceAck(requestServiceAckDecoder.logPosition());
                  break;
          }
      }
  }
  