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.quarkus.support.google.pubsub.graal;
  
  import java.io.IOException;
  import java.security.GeneralSecurityException;
  import java.time.Duration;
  import java.util.concurrent.Executor;
  import java.util.concurrent.TimeUnit;
  
  import com.google.api.core.ApiFunction;
  import com.google.api.gax.grpc.ChannelPrimer;
  import com.google.api.gax.grpc.GrpcHeaderInterceptor;
  import com.google.api.gax.grpc.GrpcInterceptorProvider;
  import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
  import com.google.api.gax.rpc.HeaderProvider;
  import com.oracle.svm.core.annotate.Alias;
  import com.oracle.svm.core.annotate.Substitute;
  import com.oracle.svm.core.annotate.TargetClass;
  import io.grpc.CallOptions;
  import io.grpc.Channel;
  import io.grpc.ChannelCredentials;
  import io.grpc.ClientCall;
  import io.grpc.ClientInterceptor;
  import io.grpc.Grpc;
  import io.grpc.ManagedChannel;
  import io.grpc.ManagedChannelBuilder;
  import io.grpc.MethodDescriptor;
  
  @TargetClass(InstantiatingGrpcChannelProvider.class)
  final class InstantiatingGrpcChannelProviderSubstitutions {
      @Alias
      private Executor executor;
      @Alias
      private HeaderProvider headerProvider;
      @Alias
      private GrpcInterceptorProvider interceptorProvider;
      @Alias
      private String endpoint;
      @Alias
      private Integer maxInboundMessageSize;
      @Alias
      private Integer maxInboundMetadataSize;
      @Alias
      private Duration keepAliveTime;
      @Alias
      private Duration keepAliveTimeout;
      @Alias
      private Boolean keepAliveWithoutCalls;
      @Alias
      private ChannelPrimer channelPrimer;
      @Alias
      private ApiFunction<ManagedChannelBuilder, ManagedChannelBuilder> channelConfigurator;
  
      @Substitute
      private ManagedChannel createSingleChannel() throws IOException {
          GrpcHeaderInterceptor headerInterceptor = new GrpcHeaderInterceptor(headerProvider.getHeaders());
          ClientInterceptor metadataHandlerInterceptor = new GrpcMetadataHandlerInterceptorTarget();
  
          int colon = endpoint.lastIndexOf(':');
          if (colon < 0) {
              throw new IllegalStateException("invalid endpoint - should have been validated: " + endpoint);
          }
          int port = Integer.parseInt(endpoint.substring(colon + 1));
          String serviceAddress = endpoint.substring(0, colon);
  
          ManagedChannelBuilder<?> builder;
          ChannelCredentials channelCredentials;
          try {
              channelCredentials = createMtlsChannelCredentials();
          } catch (GeneralSecurityException e) {
              throw new IOException(e);
          }
  
          if (channelCredentials != null) {
              builder = Grpc.newChannelBuilder(endpoint, channelCredentials);
          } else {
              builder = ManagedChannelBuilder.forAddress(serviceAddress, port);
          }
  
          builder.disableServiceConfigLookUp();
  
          builder = builder.intercept(new GrpcChannelUUIDInterceptorTarget())
                  .intercept(headerInterceptor)
                  .intercept(metadataHandlerInterceptor)
                  .userAgent(headerInterceptor.getUserAgentHeader())
                  .executor(executor);
  
          if (maxInboundMetadataSize != null) {
              builder.maxInboundMetadataSize(maxInboundMetadataSize);
          }
          if (maxInboundMessageSize != null) {
              builder.maxInboundMessageSize(maxInboundMessageSize);
          }
          if (keepAliveTime != null) {
              builder.keepAliveTime(keepAliveTime.toMillis(), TimeUnit.MILLISECONDS);
          }
          if (keepAliveTimeout != null) {
              builder.keepAliveTimeout(keepAliveTimeout.toMillis(), TimeUnit.MILLISECONDS);
          }
          if (keepAliveWithoutCalls != null) {
              builder.keepAliveWithoutCalls(keepAliveWithoutCalls);
          }
          if (interceptorProvider != null) {
              builder.intercept(interceptorProvider.getInterceptors());
          }
          if (channelConfigurator != null) {
              builder = channelConfigurator.apply(builder);
          }
  
          ManagedChannel managedChannel = builder.build();
          if (channelPrimer != null) {
              channelPrimer.primeChannel(managedChannel);
          }
          return managedChannel;
      }
  
      @Alias
      ChannelCredentials createMtlsChannelCredentials() throws IOException, GeneralSecurityException {
          throw new UnsupportedOperationException();
      }
  }
  
  @TargetClass(className = "com.google.api.gax.grpc.GrpcMetadataHandlerInterceptor")
  final class GrpcMetadataHandlerInterceptorTarget implements ClientInterceptor {
  
      @Alias()
      @Override
      public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT, RespT> method,
              final CallOptions callOptions, Channel next) {
          throw new UnsupportedOperationException();
      }
  }
  
  @TargetClass(className = "com.google.api.gax.grpc.GrpcChannelUUIDInterceptor")
  final class GrpcChannelUUIDInterceptorTarget implements ClientInterceptor {
      @Alias
      @Override
      public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT, RespT> methodDescriptor,
              CallOptions callOptions, Channel channel) {
          throw new UnsupportedOperationException();
      }
  }
  