/*

 *

 * Copyright (c) 2016 Nest Labs, Inc.

 * All rights reserved.

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 *

 *    Description:

 *      This file contains the interface for a C++ wrapper around the

 *      `tunnel.c`/`tunnel.h` interface.

 *

 */

#ifndef __wpantund__TunnelInterface__

#define __wpantund__TunnelInterface__

#include "tunnel.h"

#include "netif-mgmt.h"

#include <cstdio>

#include <string>

#include <errno.h>

#include <netinet/in.h>

#include <net/if.h>

#include "UnixSocket.h"

#include <set>

#include "IPv6Helpers.h"

#include <boost/signals2/signal.hpp>

class TunnelIPv6Interface : public nl::UnixSocket

{

public:

  TunnelIPv6Interface(const std::string& interface_name = "", int mtu = 1280);

  virtual ~TunnelIPv6Interface();

  const std::string& get_interface_name(void);

  int get_last_error(void);

  bool is_up(void);

  int set_up(bool isUp);

  bool is_running(void);

  int set_running(bool isRunning);

  // This "online" is a bit of a mashup of "up" and "running".

  // This is going to be phased out.

  bool is_online(void);

  int set_online(bool isOnline);

  const struct in6_addr& get_realm_local_address()const;

  bool add_address(const struct in6_addr *addr, int prefixlen = 64);

  bool remove_address(const struct in6_addr *addr, int prefixlen = 64);

  bool add_route(const struct in6_addr *route, int prefixlen, uint32_t metric);

  bool remove_route(const struct in6_addr *route, int prefixlen, uint32_t metric);

  bool join_multicast_address(const struct in6_addr *addr);

  bool leave_multicast_address(const struct in6_addr *addr);

  virtual void reset(void);

  virtual ssize_t write(const void* data, size_t len);

  virtual ssize_t read(void* data, size_t len);

  virtual int process(void);

  virtual int update_fd_set(fd_set *read_fd_set, fd_set *write_fd_set, fd_set *error_fd_set, int *max_fd, cms_t *timeout);

public: // Signals

  boost::signals2::signal<void(const struct in6_addr&, uint8_t)> mUnicastAddressWasAdded;

  boost::signals2::signal<void(const struct in6_addr&, uint8_t)> mUnicastAddressWasRemoved;

  boost::signals2::signal<void(const struct in6_addr&)> mMulticastAddressWasJoined;

  boost::signals2::signal<void(const struct in6_addr&)> mMulticastAddressWasLeft;

  // void linkStateChanged(isUp, isRunning);

  boost::signals2::signal<void(bool, bool)> mLinkStateChanged;

private:

  void setup_signals(void);

  void setup_mld_listener(void);

  void processNetlinkFD(void);

  void processMLDMonitorFD(void);

  void on_link_state_changed(bool isUp, bool isRunning);

  void on_address_added(const struct in6_addr &address, uint8_t prefix_len);

  void on_multicast_address_joined(const struct in6_addr &address);

  void on_address_removed(const struct in6_addr &address, uint8_t prefix_len);

  void on_multicast_address_left(const struct in6_addr &address);

private:

  std::string mInterfaceName;

  int mLastError;

  int mNetlinkFD;

  int mNetifMgmtFD;

  int mMLDMonitorFD;

  bool mIsRunning;

  bool mIsUp;

  struct Entry {

    int mPrefixLen;

    enum State {

      kWaitingToAdd,            // Waiting to add the address on interface when it becomes online

      kWaitingForAddConfirm,    // Address was added, waiting for callback to confirm the address add

    } mState;

    Entry(State state = kWaitingToAdd, int prefix_len = 64) :

      mPrefixLen(prefix_len),

      mState(state) { }

  };

  std::map<struct in6_addr, Entry> mUnicastAddresses;

  std::map<struct in6_addr, Entry> mPendingMulticastAddresses;

  enum {

    kICMPv6MLDv2Type = 143,

    kICMPv6MLDv2RecordChangeToExcludeType = 3,

    kICMPv6MLDv2RecordChangeToIncludeType = 4,

  };

};

#endif /* defined(__wpantund__TunnelInterface__) */