content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.javaagent.instrumentation.reactornetty.v1_0;
  
  import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.hasClassesNamed;
  import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.implementsInterface;
  import static net.bytebuddy.matcher.ElementMatchers.named;
  import static net.bytebuddy.matcher.ElementMatchers.returns;
  import static net.bytebuddy.matcher.ElementMatchers.takesArgument;
  import static net.bytebuddy.matcher.ElementMatchers.takesArguments;
  
  import io.opentelemetry.javaagent.bootstrap.CallDepth;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeTransformer;
  import java.util.function.BiFunction;
  import net.bytebuddy.asm.Advice;
  import net.bytebuddy.description.type.TypeDescription;
  import net.bytebuddy.matcher.ElementMatcher;
  import org.reactivestreams.Publisher;
  import reactor.core.publisher.Flux;
  import reactor.core.publisher.Mono;
  import reactor.netty.ByteBufFlux;
  import reactor.netty.ByteBufMono;
  import reactor.netty.Connection;
  import reactor.netty.http.client.HttpClient;
  import reactor.netty.http.client.HttpClientResponse;
  
  public class ResponseReceiverInstrumentation implements TypeInstrumentation {
  
    @Override
    public ElementMatcher<ClassLoader> classLoaderOptimization() {
      return hasClassesNamed("reactor.netty.http.client.HttpClient$ResponseReceiver");
    }
  
    @Override
    public ElementMatcher<TypeDescription> typeMatcher() {
      return implementsInterface(named("reactor.netty.http.client.HttpClient$ResponseReceiver"));
    }
  
    @Override
    public void transform(TypeTransformer transformer) {
      transformer.applyAdviceToMethod(
          named("response").and(takesArguments(0)).and(returns(named("reactor.core.publisher.Mono"))),
          this.getClass().getName() + "$ResponseMonoAdvice");
      transformer.applyAdviceToMethod(
          named("response")
              .and(takesArguments(1))
              .and(takesArgument(0, BiFunction.class))
              .and(returns(named("reactor.core.publisher.Flux"))),
          this.getClass().getName() + "$ResponseFluxAdvice");
      transformer.applyAdviceToMethod(
          named("responseConnection")
              .and(takesArguments(1))
              .and(takesArgument(0, BiFunction.class))
              .and(returns(named("reactor.core.publisher.Flux"))),
          this.getClass().getName() + "$ResponseConnectionAdvice");
      transformer.applyAdviceToMethod(
          named("responseContent")
              .and(takesArguments(0))
              .and(returns(named("reactor.netty.ByteBufFlux"))),
          this.getClass().getName() + "$ResponseContentAdvice");
      transformer.applyAdviceToMethod(
          named("responseSingle")
              .and(takesArguments(1))
              .and(takesArgument(0, BiFunction.class))
              .and(returns(named("reactor.core.publisher.Mono"))),
          this.getClass().getName() + "$ResponseSingleAdvice");
    }
  
    @SuppressWarnings("unused")
    public static class ResponseMonoAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class, skipOn = Advice.OnNonDefaultValue.class)
      public static HttpClient.ResponseReceiver<?> onEnter(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.This HttpClient.ResponseReceiver<?> receiver) {
  
        callDepth = CallDepth.forClass(HttpClient.ResponseReceiver.class);
        if (callDepth.getAndIncrement() > 0) {
          // execute the original method on nested calls
          return null;
        }
  
        // non-null value will skip the original method invocation
        return HttpResponseReceiverInstrumenter.instrument(receiver);
      }
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static void onExit(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.Enter HttpClient.ResponseReceiver<?> modifiedReceiver,
          @Advice.Return(readOnly = false) Mono<HttpClientResponse> returnValue) {
  
        try {
          if (modifiedReceiver != null) {
            returnValue = modifiedReceiver.response();
          }
        } finally {
          // needs to be called after original method to prevent StackOverflowError
          callDepth.decrementAndGet();
        }
      }
    }
  
    @SuppressWarnings("unused")
    public static class ResponseFluxAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class, skipOn = Advice.OnNonDefaultValue.class)
      public static HttpClient.ResponseReceiver<?> onEnter(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.This HttpClient.ResponseReceiver<?> receiver) {
  
        callDepth = CallDepth.forClass(HttpClient.ResponseReceiver.class);
        if (callDepth.getAndIncrement() > 0) {
          // execute the original method on nested calls
          return null;
        }
  
        // non-null value will skip the original method invocation
        return HttpResponseReceiverInstrumenter.instrument(receiver);
      }
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static <T extends HttpClient.ResponseReceiver<?>> void onExit(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.Enter HttpClient.ResponseReceiver<T> modifiedReceiver,
          @Advice.Argument(0)
              BiFunction<? super HttpClientResponse, ? super ByteBufFlux, ? extends Publisher<T>>
                  receiveFunction,
          @Advice.Return(readOnly = false) Flux<?> returnValue) {
  
        try {
          if (modifiedReceiver != null) {
            returnValue = modifiedReceiver.response(receiveFunction);
          }
        } finally {
          // needs to be called after original method to prevent StackOverflowError
          callDepth.decrementAndGet();
        }
      }
    }
  
    @SuppressWarnings("unused")
    public static class ResponseConnectionAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class, skipOn = Advice.OnNonDefaultValue.class)
      public static HttpClient.ResponseReceiver<?> onEnter(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.This HttpClient.ResponseReceiver<?> receiver) {
  
        callDepth = CallDepth.forClass(HttpClient.ResponseReceiver.class);
        if (callDepth.getAndIncrement() > 0) {
          // execute the original method on nested calls
          return null;
        }
  
        // non-null value will skip the original method invocation
        return HttpResponseReceiverInstrumenter.instrument(receiver);
      }
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static <T extends HttpClient.ResponseReceiver<?>> void onExit(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.Enter HttpClient.ResponseReceiver<T> modifiedReceiver,
          @Advice.Argument(0)
              BiFunction<? super HttpClientResponse, ? super Connection, ? extends Publisher<T>>
                  receiveFunction,
          @Advice.Return(readOnly = false) Flux<?> returnValue) {
  
        try {
          if (modifiedReceiver != null) {
            returnValue = modifiedReceiver.responseConnection(receiveFunction);
          }
        } finally {
          // needs to be called after original method to prevent StackOverflowError
          callDepth.decrementAndGet();
        }
      }
    }
  
    @SuppressWarnings("unused")
    public static class ResponseContentAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class, skipOn = Advice.OnNonDefaultValue.class)
      public static HttpClient.ResponseReceiver<?> onEnter(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.This HttpClient.ResponseReceiver<?> receiver) {
  
        callDepth = CallDepth.forClass(HttpClient.ResponseReceiver.class);
        if (callDepth.getAndIncrement() > 0) {
          // execute the original method on nested calls
          return null;
        }
  
        // non-null value will skip the original method invocation
        return HttpResponseReceiverInstrumenter.instrument(receiver);
      }
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static void onExit(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.Enter HttpClient.ResponseReceiver<?> modifiedReceiver,
          @Advice.Return(readOnly = false) ByteBufFlux returnValue) {
  
        try {
          if (modifiedReceiver != null) {
            returnValue = modifiedReceiver.responseContent();
          }
        } finally {
          // needs to be called after original method to prevent StackOverflowError
          callDepth.decrementAndGet();
        }
      }
    }
  
    @SuppressWarnings("unused")
    public static class ResponseSingleAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class, skipOn = Advice.OnNonDefaultValue.class)
      public static HttpClient.ResponseReceiver<?> onEnter(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.This HttpClient.ResponseReceiver<?> receiver) {
  
        callDepth = CallDepth.forClass(HttpClient.ResponseReceiver.class);
        if (callDepth.getAndIncrement() > 0) {
          // execute the original method on nested calls
          return null;
        }
  
        // non-null value will skip the original method invocation
        return HttpResponseReceiverInstrumenter.instrument(receiver);
      }
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static <T extends HttpClient.ResponseReceiver<?>> void onExit(
          @Advice.Local("otelCallDepth") CallDepth callDepth,
          @Advice.Enter HttpClient.ResponseReceiver<T> modifiedReceiver,
          @Advice.Argument(0)
              BiFunction<? super HttpClientResponse, ? super ByteBufMono, ? extends Mono<T>>
                  receiveFunction,
          @Advice.Return(readOnly = false) Mono<?> returnValue) {
  
        try {
          if (modifiedReceiver != null) {
            returnValue = modifiedReceiver.responseSingle(receiveFunction);
          }
        } finally {
          // needs to be called after original method to prevent StackOverflowError
          callDepth.decrementAndGet();
        }
      }
    }
  }
  