#pragma once

#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#include <env.h>

#include <ngtcp2/ngtcp2.h>

#include <node_internals.h>

#include <node_realm.h>

#include <v8.h>

#include <string>

#include "defs.h"

namespace node::quic {

// PreferredAddress is a helper class used only when a client Session receives

// an advertised preferred address from a server. The helper provides

// information about the server advertised preferred address and allows

// the preferred address to be selected.

class PreferredAddress final {

 public:

  enum class Policy : uint8_t {

    // Ignore the server-advertised preferred address.

    IGNORE_PREFERRED,

    // Use the server-advertised preferred address.

    USE_PREFERRED,

  };

  static v8::Maybe<Policy> tryGetPolicy(Environment* env,

                                        v8::Local<v8::Value> value);

  static inline v8::Maybe<Policy> tryGetPolicy(Realm* realm,

                                               v8::Local<v8::Value> value) {

    return tryGetPolicy(realm->env(), value);

  }

  static void Initialize(Environment* env, v8::Local<v8::Object> target);

  static inline void Initialize(Realm* realm, v8::Local<v8::Object> target) {

    return Initialize(realm->env(), target);

  }

  struct AddressInfo final {

    char host[NI_MAXHOST];

    int family;

    uint16_t port;

    std::string_view address;

  };

  explicit PreferredAddress(ngtcp2_path* dest,

                            const ngtcp2_preferred_addr* paddr);

  DISALLOW_COPY_AND_MOVE(PreferredAddress)

  void* operator new(size_t) = delete;

  void operator delete(void*) = delete;

  void Use(const AddressInfo& address);

  std::optional<const AddressInfo> ipv4() const;

  std::optional<const AddressInfo> ipv6() const;

  const CID cid() const;

  // Set the preferred address in the transport params.

  // The address family (ipv4 or ipv6) will be automatically

  // detected from the given addr. Any other address family

  // will be ignored.

  static void Set(ngtcp2_transport_params* params, const sockaddr* addr);

 private:

  ngtcp2_path* dest_;

  const ngtcp2_preferred_addr* paddr_;

};

}  // namespace node::quic

#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS