#pragma once

#include "stream.hpp"
#include "log.hpp"

#include <charconv>
#include <cstdint>
#include <string>
#include <string_view>

#include <uvw/tcp.h>

namespace llarp::quic::tunnel
{
  // The server sends back a 0x00 to signal that the remote TCP connection was established and that
  // it is now accepting stream data; the client is not allowed to send any other data down the
  // stream until this comes back (any data sent down the stream before then is discarded.)
  inline constexpr std::byte CONNECT_INIT{0x00};
  // QUIC application error codes we sent on failures:
  // Failure to establish an initial connection:
  inline constexpr uint64_t ERROR_CONNECT{0x5471907};
  // Error if we receive something other than CONNECT_INIT as the initial stream data from the
  // server
  inline constexpr uint64_t ERROR_BAD_INIT{0x5471908};
  // Close error code sent if we get an error on the TCP socket (other than an initial connect
  // failure)
  inline constexpr uint64_t ERROR_TCP{0x5471909};

  // We pause reading from the local TCP socket if we have more than this amount of outstanding
  // unacked data in the quic tunnel, then resume once it drops below this.
  inline constexpr size_t PAUSE_SIZE = 64 * 1024;

  // Callbacks for network events.  The uvw::TCPHandle client must contain a shared pointer to the
  // associated llarp::quic::Stream in its data, and the llarp::quic::Stream must contain a weak
  // pointer to the uvw::TCPHandle.

  // Callback when we receive data to go out over lokinet, i.e. read from the local TCP socket
  void
  on_outgoing_data(uvw::DataEvent& event, uvw::TCPHandle& client);

  // Callback when we receive data from lokinet to write to the local TCP socket
  void
  on_incoming_data(llarp::quic::Stream& stream, llarp::quic::bstring_view bdata);

  // Callback to handle and discard the first incoming 0x00 byte that initiates the stream
  void
  on_init_incoming_data(llarp::quic::Stream& stream, llarp::quic::bstring_view bdata);

  // Creates a new tcp handle that forwards incoming data/errors/closes into appropriate actions on
  // the given quic stream.
  void
  install_stream_forwarding(uvw::TCPHandle& tcp, llarp::quic::Stream& stream);

}  // namespace llarp::quic::tunnel