/*
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * 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
 *
 *     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.
 */

#include <folly/experimental/coro/GtestHelpers.h>
#include <folly/portability/GTest.h>

#include <thrift/lib/cpp2/async/AsyncClient.h>
#include <thrift/lib/cpp2/util/ScopedServerInterfaceThread.h>

#include <thrift/lib/cpp2/async/tests/gen-cpp2/test_clients.h>
#include <thrift/lib/cpp2/async/tests/gen-cpp2/test_handlers.h>

class TestHandler
    : public apache::thrift::ServiceHandler<apache::thrift::test::Test> {
  folly::coro::Task<void> co_func() override { co_return; }
};

CO_TEST(AsyncClientTest, ZeroDependency) {
  class TestEventHandler : public apache::thrift::TProcessorEventHandler {
    void preRead(void* /*ctx*/, const char* /*fn_name*/) override {
      preReadCallCount++;
    }
    void postWrite(
        void* /*ctx*/, const char* /*fn_name*/, uint32_t /*bytes*/) override {
      postWriteCallCount++;
    }

   public:
    int preReadCallCount = 0;
    int postWriteCallCount = 0;
  };
  auto eventHandler = std::make_shared<TestEventHandler>();
  apache::thrift::TClientBase::addClientEventHandler(eventHandler);
  SCOPE_EXIT {
    apache::thrift::TClientBase::removeClientEventHandler(eventHandler);
  };

  using ClientType = apache::thrift::Client<apache::thrift::test::Test>;
  std::unique_ptr<ClientType> client =
      apache::thrift::makeTestClient(std::make_shared<TestHandler>());

  std::unique_ptr<ClientType> zeroDepClient = std::make_unique<ClientType>(
      client->getChannelShared(), ClientType::Options::zeroDependency());

  co_await zeroDepClient->co_func();
  EXPECT_EQ(eventHandler->preReadCallCount, 0);
  EXPECT_EQ(eventHandler->postWriteCallCount, 0);

  co_await client->co_func();
  EXPECT_EQ(eventHandler->preReadCallCount, 1);
  EXPECT_EQ(eventHandler->postWriteCallCount, 1);
}