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.camel.component.google.pubsub.consumer;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.Callable;
  
  import com.google.cloud.pubsub.v1.stub.SubscriberStub;
  import com.google.pubsub.v1.AcknowledgeRequest;
  import com.google.pubsub.v1.ModifyAckDeadlineRequest;
  import org.apache.camel.Exchange;
  import org.apache.camel.RuntimeCamelException;
  import org.apache.camel.component.google.pubsub.GooglePubsubConstants;
  
  public class AcknowledgeSync implements GooglePubsubAcknowledge {
  
      //Supplier cannot be used because of thrown exception (Callback used instead)
      private final Callable<SubscriberStub> subscriberStubSupplier;
      private final String subscriptionName;
  
      public AcknowledgeSync(Callable<SubscriberStub> subscriberStubSupplier, String subscriptionName) {
          this.subscriberStubSupplier = subscriberStubSupplier;
          this.subscriptionName = subscriptionName;
      }
  
      @Override
      public void ack(Exchange exchange) {
          AcknowledgeRequest ackRequest = AcknowledgeRequest.newBuilder()
                  .addAllAckIds(getAckIdList(exchange))
                  .setSubscription(subscriptionName).build();
          try (SubscriberStub subscriber = subscriberStubSupplier.call()) {
              subscriber.acknowledgeCallable().call(ackRequest);
          } catch (Exception e) {
              throw new RuntimeCamelException(e);
          }
      }
  
      @Override
      public void nack(Exchange exchange) {
          // There is no explicit nack on the subscriber client. Using modifyAckDeadline with 0 seconds
          // is the recommended way to nack a message. https://github.com/googleapis/python-pubsub/pull/123
          ModifyAckDeadlineRequest nackRequest = ModifyAckDeadlineRequest.newBuilder()
                  .addAllAckIds(getAckIdList(exchange))
                  .setSubscription(subscriptionName)
                  .setAckDeadlineSeconds(0).build();
  
          try (SubscriberStub subscriber = subscriberStubSupplier.call()) {
              subscriber.modifyAckDeadlineCallable().call(nackRequest);
          } catch (Exception e) {
              throw new RuntimeCamelException(e);
          }
      }
  
      private List<String> getAckIdList(Exchange exchange) {
          List<String> ackList = new ArrayList<>();
  
          if (exchange.getIn().getBody() instanceof List) {
              for (Object body : exchange.getIn().getBody(List.class)) {
                  if (body instanceof Exchange) {
                      String ackId = exchange.getIn().getHeader(GooglePubsubConstants.ACK_ID, String.class);
                      if (null != ackId) {
                          ackList.add(ackId);
                      }
                  }
              }
          }
  
          String ackId = exchange.getIn().getHeader(GooglePubsubConstants.ACK_ID, String.class);
          if (null != ackId) {
              ackList.add(ackId);
          }
  
          return ackList;
      }
  }
  