#pragma once

#include <cstdint>

#include <memory>

#include "envoy/http/codec.h"

#include "envoy/tcp/conn_pool.h"

#include "source/common/buffer/watermark_buffer.h"

#include "source/common/common/cleanup.h"

#include "source/common/common/logger.h"

#include "source/common/config/well_known_names.h"

#include "source/common/router/upstream_request.h"

#include "source/common/stream_info/stream_info_impl.h"

namespace Envoy {

namespace Extensions {

namespace Upstreams {

namespace Http {

namespace Tcp {

class TcpConnPool : public Router::GenericConnPool, public Envoy::Tcp::ConnectionPool::Callbacks {

public:

  TcpConnPool(Upstream::HostConstSharedPtr host, Upstream::ThreadLocalCluster& thread_local_cluster,

  // Router::GenericConnPool

  // Tcp::ConnectionPool::Callbacks

  void onPoolFailure(ConnectionPool::PoolFailureReason reason,

                     absl::string_view transport_failure_reason,

  void onPoolReady(Envoy::Tcp::ConnectionPool::ConnectionDataPtr&& conn_data,

                   Upstream::HostDescriptionConstSharedPtr host) override;

private:

  absl::optional<Envoy::Upstream::TcpPoolData> conn_pool_data_;

  Envoy::Tcp::ConnectionPool::Cancellable* upstream_handle_{};

  Router::GenericConnectionPoolCallbacks* callbacks_{};

};

class TcpUpstream : public Router::GenericUpstream,

                    public Envoy::Tcp::ConnectionPool::UpstreamCallbacks {

public:

  TcpUpstream(Router::UpstreamToDownstream* upstream_request,

              Envoy::Tcp::ConnectionPool::ConnectionDataPtr&& upstream);

  // GenericUpstream

  void encodeData(Buffer::Instance& data, bool end_stream) override;

  Envoy::Http::Status encodeHeaders(const Envoy::Http::RequestHeaderMap&, bool end_stream) override;

  void encodeTrailers(const Envoy::Http::RequestTrailerMap&) override;

  void readDisable(bool disable) override;

  void resetStream() override;

  // Tcp::ConnectionPool::UpstreamCallbacks

  void onUpstreamData(Buffer::Instance& data, bool end_stream) override;

  void onEvent(Network::ConnectionEvent event) override;

  void onAboveWriteBufferHighWatermark() override;

  void onBelowWriteBufferLowWatermark() override;

private:

  Router::UpstreamToDownstream* upstream_request_;

  Envoy::Tcp::ConnectionPool::ConnectionDataPtr upstream_conn_data_;

  StreamInfo::BytesMeterSharedPtr bytes_meter_{std::make_shared<StreamInfo::BytesMeter>()};

  bool downstream_complete_ = false;

  const bool force_reset_on_upstream_half_close_{};

};

} // namespace Tcp

} // namespace Http

} // namespace Upstreams

} // namespace Extensions

} // namespace Envoy