/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

// Original author: ekr@rtfm.com

// Some of this code is cut-and-pasted from nICEr. Copyright is:

/*
Copyright (c) 2007, Adobe Systems, Incorporated
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* Neither the name of Adobe Systems, Network Resonance nor the names of its
  contributors may be used to endorse or promote products derived from
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/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

// Original author: ekr@rtfm.com

// This is a wrapper around the nICEr ICE stack
#ifndef nricectx_h__
#define nricectx_h__

#include <string>
#include <vector>

#include "sigslot.h"

#include "prnetdb.h"

#include "mozilla/RefPtr.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/UniquePtr.h"
#include "nsAutoPtr.h"
#include "nsIEventTarget.h"
#include "nsITimer.h"

#include "m_cpp_utils.h"

typedef struct nr_ice_ctx_ nr_ice_ctx;
typedef struct nr_ice_peer_ctx_ nr_ice_peer_ctx;
typedef struct nr_ice_media_stream_ nr_ice_media_stream;
typedef struct nr_ice_handler_ nr_ice_handler;
typedef struct nr_ice_handler_vtbl_ nr_ice_handler_vtbl;
typedef struct nr_ice_candidate_ nr_ice_candidate;
typedef struct nr_ice_cand_pair_ nr_ice_cand_pair;
typedef struct nr_ice_stun_server_ nr_ice_stun_server;
typedef struct nr_ice_turn_server_ nr_ice_turn_server;
typedef struct nr_resolver_ nr_resolver;
typedef struct nr_proxy_tunnel_config_ nr_proxy_tunnel_config;

typedef void* NR_SOCKET;

namespace mozilla {

// Timestamps set whenever a packet is dropped due to global rate limiting
// (see nr_socket_prsock.cpp)
TimeStamp nr_socket_short_term_violation_time();
TimeStamp nr_socket_long_term_violation_time();

class NrIceMediaStream;

extern const char kNrIceTransportUdp[];
extern const char kNrIceTransportTcp[];

class NrIceStunServer {
 public:
  explicit NrIceStunServer(const PRNetAddr& addr) : has_addr_(true) {
    memcpy(&addr_, &addr, sizeof(addr));
  }

   // The main function to use. Will take either an address or a hostname.
  static UniquePtr<NrIceStunServer> Create(const std::string& addr, uint16_t port,
      const char *transport = kNrIceTransportUdp) {
    UniquePtr<NrIceStunServer> server(new NrIceStunServer(transport));

    nsresult rv = server->Init(addr, port);
    if (NS_FAILED(rv))
      return nullptr;

    return server;
  }

  nsresult ToNicerStunStruct(nr_ice_stun_server* server) const;

 protected:
  explicit NrIceStunServer(const char *transport) :
      addr_(), transport_(transport) {}

  nsresult Init(const std::string& addr, uint16_t port) {
    PRStatus status = PR_StringToNetAddr(addr.c_str(), &addr_);
    if (status == PR_SUCCESS) {
      // Parseable as an address
      addr_.inet.port = PR_htons(port);
      port_ = port;
      has_addr_ = true;
      return NS_OK;
    }
    else if (addr.size() < 256) {
      // Apparently this is a hostname.
      host_ = addr;
      port_ = port;
      has_addr_ = false;
      return NS_OK;
    }

    return NS_ERROR_FAILURE;
  }

  bool has_addr_;
  std::string host_;
  uint16_t port_;
  PRNetAddr addr_;
  std::string transport_;
};

class NrIceTurnServer : public NrIceStunServer {
 public:
  static UniquePtr<NrIceTurnServer> Create(const std::string& addr, uint16_t port,
                                           const std::string& username,
                                           const std::vector<unsigned char>& password,
                                           const char *transport = kNrIceTransportUdp) {
    UniquePtr<NrIceTurnServer> server(new NrIceTurnServer(username, password, transport));

    nsresult rv = server->Init(addr, port);
    if (NS_FAILED(rv))
      return nullptr;

    return server;
  }

  nsresult ToNicerTurnStruct(nr_ice_turn_server *server) const;

 private:
  NrIceTurnServer(const std::string& username,
                  const std::vector<unsigned char>& password,
                  const char *transport) :
      NrIceStunServer(transport), username_(username), password_(password) {}

  std::string username_;
  std::vector<unsigned char> password_;
};

class NrIceProxyServer {
 public:
  NrIceProxyServer(const std::string& host, uint16_t port,
                   const std::string& alpn) :
    host_(host), port_(port), alpn_(alpn) {
  }

  NrIceProxyServer() : NrIceProxyServer("", 0, "") {}

  const std::string& host() const { return host_; }
  uint16_t port() const { return port_; }
  const std::string& alpn() const { return alpn_; }

 private:
  std::string host_;
  uint16_t port_;
  std::string alpn_;
};

class TestNat;

class NrIceCtx {
 public:
  enum ConnectionState { ICE_CTX_INIT,
                         ICE_CTX_CHECKING,
                         ICE_CTX_OPEN,
                         ICE_CTX_FAILED
  };

  enum GatheringState { ICE_CTX_GATHER_INIT,
                        ICE_CTX_GATHER_STARTED,
                        ICE_CTX_GATHER_COMPLETE
  };

  enum Controlling { ICE_CONTROLLING,
                     ICE_CONTROLLED
  };

  enum Policy { ICE_POLICY_NONE,
                ICE_POLICY_RELAY,
                ICE_POLICY_ALL
  };

  static void Init(bool allow_loopback = false,
                   bool tcp_enabled = true,
                   bool allow_link_local = false);

  // TODO(ekr@rtfm.com): Too many bools here. Bug 1193437.
  static RefPtr<NrIceCtx> Create(const std::string& name,
                                 bool offerer,
                                 bool allow_loopback = false,
                                 bool tcp_enabled = true,
                                 bool allow_link_local = false,
                                 bool hide_non_default = false,
                                 Policy policy = ICE_POLICY_ALL);

  int SetNat(const RefPtr<TestNat>& aNat);

  // Deinitialize all ICE global state. Used only for testing.
  static void internal_DeinitializeGlobal();


  nr_ice_ctx *ctx() { return ctx_; }
  nr_ice_peer_ctx *peer() { return peer_; }

  // Testing only.
  void destroy_peer_ctx();

  // Create a media stream
  RefPtr<NrIceMediaStream> CreateStream(const std::string& name,
                                        int components);

  void SetStream(size_t index, NrIceMediaStream* stream);

  RefPtr<NrIceMediaStream> GetStream(size_t index) {
    if (index < streams_.size()) {
      return streams_[index];
    }
    return nullptr;
  }

  // Some might be null
  size_t GetStreamCount() const
  {
    return streams_.size();
  }

  // The name of the ctx
  const std::string& name() const { return name_; }

  // Get ufrag and password.
  std::string ufrag() const;
  std::string pwd() const;

  // Current state
  ConnectionState connection_state() const {
    return connection_state_;
  }

  // Current state
  GatheringState gathering_state() const {
    return gathering_state_;
  }

  // Get the global attributes
  std::vector<std::string> GetGlobalAttributes();

  // Set the other side's global attributes
  nsresult ParseGlobalAttributes(std::vector<std::string> attrs);

  // Set whether we are controlling or not.
  nsresult SetControlling(Controlling controlling);

  Controlling GetControlling();

  // Set whether we're allowed to produce none, relay or all candidates.
  // TODO(jib@mozilla.com): Work out what change means mid-connection (1181768)
  nsresult SetPolicy(Policy policy);

  Policy policy() const {
    return policy_;
  }

  // Set the STUN servers. Must be called before StartGathering
  // (if at all).
  nsresult SetStunServers(const std::vector<NrIceStunServer>& stun_servers);

  // Set the TURN servers. Must be called before StartGathering
  // (if at all).
  nsresult SetTurnServers(const std::vector<NrIceTurnServer>& turn_servers);

  // Provide the resolution provider. Must be called before
  // StartGathering.
  nsresult SetResolver(nr_resolver *resolver);

  // Provide the proxy address. Must be called before
  // StartGathering.
  nsresult SetProxyServer(const NrIceProxyServer& proxy_server);

  // Start ICE gathering
  nsresult StartGathering();

  // Start checking
  nsresult StartChecks();

  // Finalize the ICE negotiation. I.e., there will be no
  // more forking.
  nsresult Finalize();

  // Are we trickling?
  bool generating_trickle() const { return trickle_; }

  // Signals to indicate events. API users can (and should)
  // register for these.
  sigslot::signal2<NrIceCtx*, NrIceCtx::GatheringState>
    SignalGatheringStateChange;
  sigslot::signal2<NrIceCtx*, NrIceCtx::ConnectionState>
    SignalConnectionStateChange;

  // The thread to direct method calls to
  nsCOMPtr<nsIEventTarget> thread() { return sts_target_; }

  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(NrIceCtx)

 private:
  NrIceCtx(const std::string& name,
           bool offerer,
           Policy policy);

  virtual ~NrIceCtx();

  DISALLOW_COPY_ASSIGN(NrIceCtx);

  // Callbacks for nICEr
  static void gather_cb(NR_SOCKET s, int h, void *arg);  // ICE gather complete

  // Handler implementation
  static int select_pair(void *obj,nr_ice_media_stream *stream,
                         int component_id, nr_ice_cand_pair **potentials,
                         int potential_ct);
  static int stream_ready(void *obj, nr_ice_media_stream *stream);
  static int stream_failed(void *obj, nr_ice_media_stream *stream);
  static int ice_checking(void *obj, nr_ice_peer_ctx *pctx);
  static int ice_completed(void *obj, nr_ice_peer_ctx *pctx);
  static int msg_recvd(void *obj, nr_ice_peer_ctx *pctx,
                       nr_ice_media_stream *stream, int component_id,
                       unsigned char *msg, int len);
  static void trickle_cb(void *arg, nr_ice_ctx *ctx, nr_ice_media_stream *stream,
                         int component_id, nr_ice_candidate *candidate);

  // Find a media stream by stream ptr. Gross
  RefPtr<NrIceMediaStream> FindStream(nr_ice_media_stream *stream);

  // Set the state
  void SetConnectionState(ConnectionState state);

  // Set the state
  void SetGatheringState(GatheringState state);

  ConnectionState connection_state_;
  GatheringState gathering_state_;
  const std::string name_;
  bool offerer_;
  std::vector<RefPtr<NrIceMediaStream> > streams_;
  nr_ice_ctx *ctx_;
  nr_ice_peer_ctx *peer_;
  nr_ice_handler_vtbl* ice_handler_vtbl_;  // Must be pointer
  nr_ice_handler* ice_handler_;  // Must be pointer
  bool trickle_;
  nsCOMPtr<nsIEventTarget> sts_target_; // The thread to run on
  Policy policy_;
  RefPtr<TestNat> nat_;
};


}  // close namespace
#endif
