// Copyright Joyent, Inc. and other Node contributors.

//

// Permission is hereby granted, free of charge, to any person obtaining a

// copy of this software and associated documentation files (the

// "Software"), to deal in the Software without restriction, including

// without limitation the rights to use, copy, modify, merge, publish,

// distribute, sublicense, and/or sell copies of the Software, and to permit

// persons to whom the Software is furnished to do so, subject to the

// following conditions:

//

// The above copyright notice and this permission notice shall be included

// in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN

// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,

// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE

// USE OR OTHER DEALINGS IN THE SOFTWARE.

#ifndef SRC_UDP_WRAP_H_

#define SRC_UDP_WRAP_H_

#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#include "handle_wrap.h"

#include "req_wrap.h"

#include "node_sockaddr.h"

#include "uv.h"

#include "v8.h"

namespace node {

class UDPWrapBase;

// A listener that can be attached to an `UDPWrapBase` object and generally

// manages its I/O activity. This is similar to `StreamListener`.

class UDPListener {

 public:

  virtual ~UDPListener();

  // Called right before data is received from the socket. Must return a

  // buffer suitable for reading data into, that is then passed to OnRecv.

  virtual uv_buf_t OnAlloc(size_t suggested_size) = 0;

  // Called right after data is received from the socket, and includes

  // information about the source address. If `nread` is negative, an error

  // has occurred, and it represents a libuv error code.

  virtual void OnRecv(ssize_t nread,

                      const uv_buf_t& buf,

                      const sockaddr* addr,

                      unsigned int flags) = 0;

  // Called when an asynchronous request for writing data is created.

  // The `msg_size` value contains the total size of the data to be sent,

  // but may be ignored by the implementation of this Method.

  // The return value is later passed to OnSendDone.

  virtual ReqWrap<uv_udp_send_t>* CreateSendWrap(size_t msg_size) = 0;

  // Called when an asynchronous request for writing data has finished.

  // If status is negative, an error has occurred, and it represents a libuv

  // error code.

  virtual void OnSendDone(ReqWrap<uv_udp_send_t>* wrap, int status) = 0;

  // Optional callback that is called after the socket has been bound.

  inline UDPWrapBase* udp() const { return wrap_; }

 protected:

  UDPWrapBase* wrap_ = nullptr;

  friend class UDPWrapBase;

};

class UDPWrapBase {

 public:

  // While UDPWrapBase itself does not extend from HandleWrap, classes

  // derived from it will (like UDPWrap)

  enum InternalFields {

    kUDPWrapBaseField = HandleWrap::kInternalFieldCount,

    kInternalFieldCount

  };

  virtual ~UDPWrapBase();

  // Start emitting OnAlloc() + OnRecv() events on the listener.

  virtual int RecvStart() = 0;

  // Stop emitting OnAlloc() + OnRecv() events on the listener.

  virtual int RecvStop() = 0;

  // Send a chunk of data over this socket. This may call CreateSendWrap()

  // on the listener if an async transmission is necessary.

  virtual ssize_t Send(uv_buf_t* bufs,

                       size_t nbufs,

                       const sockaddr* addr) = 0;

  virtual SocketAddress GetPeerName() = 0;

  virtual SocketAddress GetSockName() = 0;

  // Returns an AsyncWrap object with the same lifetime as this object.

  virtual AsyncWrap* GetAsyncWrap() = 0;

  void set_listener(UDPListener* listener);

  UDPListener* listener() const;

  static UDPWrapBase* FromObject(v8::Local<v8::Object> obj);

  static void RecvStart(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void RecvStop(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void AddMethods(Environment* env, v8::Local<v8::FunctionTemplate> t);

 private:

  UDPListener* listener_ = nullptr;

};

class UDPWrap final : public HandleWrap,

                      public UDPWrapBase,

                      public UDPListener {

 public:

  enum SocketType {

    SOCKET

  };

  static void Initialize(v8::Local<v8::Object> target,

                         v8::Local<v8::Value> unused,

                         v8::Local<v8::Context> context,

                         void* priv);

  static void GetFD(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void New(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Open(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Bind(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Connect(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Send(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Bind6(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Connect6(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Send6(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Disconnect(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void AddMembership(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void DropMembership(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void AddSourceSpecificMembership(

      const v8::FunctionCallbackInfo<v8::Value>& args);

  static void DropSourceSpecificMembership(

      const v8::FunctionCallbackInfo<v8::Value>& args);

  static void SetMulticastInterface(

      const v8::FunctionCallbackInfo<v8::Value>& args);

  static void SetMulticastTTL(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void SetMulticastLoopback(

      const v8::FunctionCallbackInfo<v8::Value>& args);

  static void SetBroadcast(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void SetTTL(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void BufferSize(const v8::FunctionCallbackInfo<v8::Value>& args);

  // UDPListener implementation

  uv_buf_t OnAlloc(size_t suggested_size) override;

  void OnRecv(ssize_t nread,

              const uv_buf_t& buf,

              const sockaddr* addr,

              unsigned int flags) override;

  ReqWrap<uv_udp_send_t>* CreateSendWrap(size_t msg_size) override;

  void OnSendDone(ReqWrap<uv_udp_send_t>* wrap, int status) override;

  // UDPWrapBase implementation

  int RecvStart() override;

  int RecvStop() override;

  ssize_t Send(uv_buf_t* bufs,

               size_t nbufs,

               const sockaddr* addr) override;

  SocketAddress GetPeerName() override;

  SocketAddress GetSockName() override;

  AsyncWrap* GetAsyncWrap() override;

  static v8::MaybeLocal<v8::Object> Instantiate(Environment* env,

                                                AsyncWrap* parent,

                                                SocketType type);

 private:

  typedef uv_udp_t HandleType;

  template <typename T,

            int (*F)(const typename T::HandleType*, sockaddr*, int*)>

  friend void GetSockOrPeerName(const v8::FunctionCallbackInfo<v8::Value>&);

  UDPWrap(Environment* env, v8::Local<v8::Object> object);

  static void DoBind(const v8::FunctionCallbackInfo<v8::Value>& args,

                     int family);

  static void DoConnect(const v8::FunctionCallbackInfo<v8::Value>& args,

                     int family);

  static void DoSend(const v8::FunctionCallbackInfo<v8::Value>& args,

                     int family);

  static void SetMembership(const v8::FunctionCallbackInfo<v8::Value>& args,

                            uv_membership membership);

  static void SetSourceMembership(

      const v8::FunctionCallbackInfo<v8::Value>& args,

      uv_membership membership);

  static void OnAlloc(uv_handle_t* handle,

                      size_t suggested_size,

                      uv_buf_t* buf);

  static void OnRecv(uv_udp_t* handle,

                     ssize_t nread,

                     const uv_buf_t* buf,

                     const struct sockaddr* addr,

                     unsigned int flags);

  uv_udp_t handle_;

  bool current_send_has_callback_;

  v8::Local<v8::Object> current_send_req_wrap_;

};

int sockaddr_for_family(int address_family,

                        const char* address,

                        const unsigned short port,

                        sockaddr_storage* addr);

}  // namespace node

#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#endif  // SRC_UDP_WRAP_H_