/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (C) 2014 Named Data Networking Project
 * See COPYING for copyright and distribution information.
 */

#include "face-manager.hpp"

#include "core/face-uri.hpp"
#include "fw/face-table.hpp"

#include "face/tcp-factory.hpp"
#include "face/udp-factory.hpp"
#include "face/unix-stream-factory.hpp"
#include "face/ethernet-factory.hpp"

#ifdef __linux__
#include <netinet/ether.h>
#else
#include <net/ethernet.h>
#endif


namespace nfd {

NFD_LOG_INIT("FaceManager");

const Name FaceManager::COMMAND_PREFIX = "/localhost/nfd/faces";

const size_t FaceManager::COMMAND_UNSIGNED_NCOMPS =
  FaceManager::COMMAND_PREFIX.size() +
  1 + // verb
  1;  // verb options

const size_t FaceManager::COMMAND_SIGNED_NCOMPS =
  FaceManager::COMMAND_UNSIGNED_NCOMPS +
  0; // No signed Interest support in mock, otherwise 4 (timestamp, nonce, signed info tlv, signature tlv)

const FaceManager::VerbAndProcessor FaceManager::COMMAND_VERBS[] =
  {
    VerbAndProcessor(
                     Name::Component("create"),
                     &FaceManager::createFace
                     ),

    VerbAndProcessor(
                     Name::Component("destroy"),
                     &FaceManager::destroyFace
                     ),
  };


FaceManager::FaceManager(FaceTable& faceTable,
                         shared_ptr<AppFace> face)
  : ManagerBase(face)
  , m_faceTable(faceTable)
  , m_verbDispatch(COMMAND_VERBS,
                   COMMAND_VERBS +
                   (sizeof(COMMAND_VERBS) / sizeof(VerbAndProcessor)))
{
  face->setInterestFilter("/localhost/nfd/faces",
                          bind(&FaceManager::onFaceRequest, this, _2));
}

void
FaceManager::setConfigFile(ConfigFile& configFile)
{
  configFile.addSectionHandler("face_system",
                               bind(&FaceManager::onConfig, this, _1, _2));
}


void
FaceManager::onConfig(const ConfigSection& configSection, bool isDryRun)
{
  bool hasSeenUnix = false;
  bool hasSeenTcp = false;
  bool hasSeenUdp = false;
  bool hasSeenEther = false;

  for (ConfigSection::const_iterator item = configSection.begin();
       item != configSection.end();
       ++item)
    {
      if (item->first == "unix")
        {
          if (hasSeenUnix)
            throw Error("Duplicate \"unix\" section");
          hasSeenUnix = true;

          processSectionUnix(item->second, isDryRun);
        }
      else if (item->first == "tcp")
        {
          if (hasSeenTcp)
            throw Error("Duplicate \"tcp\" section");
          hasSeenTcp = true;

          processSectionTcp(item->second, isDryRun);
        }
      else if (item->first == "udp")
        {
          if (hasSeenUdp)
            throw Error("Duplicate \"udp\" section");
          hasSeenUdp = true;

          processSectionUdp(item->second, isDryRun);
        }
      else if (item->first == "ether")
        {
          if (hasSeenEther)
            throw Error("Duplicate \"ether\" section");
          hasSeenEther = true;

          processSectionEther(item->second, isDryRun);
        }
      else
        {
          throw Error("Unrecognized option \"" + item->first + "\"");
        }
    }
}

void
FaceManager::processSectionUnix(const ConfigSection& configSection, bool isDryRun)
{
  // ; the unix section contains settings of UNIX stream faces and channels
  // unix
  // {
  //   listen yes ; set to 'no' to disable UNIX stream listener, default 'yes'
  //   path /var/run/nfd.sock ; UNIX stream listener path
  // }

  bool needToListen = true;
  std::string path = "/var/run/nfd.sock";

  for (ConfigSection::const_iterator i = configSection.begin();
       i != configSection.end();
       ++i)
    {
      if (i->first == "path")
        {
          path = i->second.get_value<std::string>();
        }
      else if (i->first == "listen")
        {
          needToListen = parseYesNo(i, i->first, "unix");
        }
      else
        {
          throw ConfigFile::Error("Unrecognized option \"" + i->first + "\" in \"unix\" section");
        }
    }

  if (!isDryRun)
    {
      shared_ptr<UnixStreamFactory> factory = make_shared<UnixStreamFactory>();
      shared_ptr<UnixStreamChannel> unixChannel = factory->createChannel(path);

      if (needToListen)
        {
          // Should acceptFailed callback be used somehow?
          unixChannel->listen(bind(&FaceTable::add, &m_faceTable, _1),
                              UnixStreamChannel::ConnectFailedCallback());
        }

      m_factories.insert(std::make_pair("unix", factory));
    }
}

void
FaceManager::processSectionTcp(const ConfigSection& configSection, bool isDryRun)
{
  // ; the tcp section contains settings of TCP faces and channels
  // tcp
  // {
  //   listen yes ; set to 'no' to disable TCP listener, default 'yes'
  //   port 6363 ; TCP listener port number
  // }

  std::string port = "6363";
  bool needToListen = true;

  for (ConfigSection::const_iterator i = configSection.begin();
       i != configSection.end();
       ++i)
    {
      if (i->first == "port")
        {
          port = i->second.get_value<std::string>();
        }
      else if (i->first == "listen")
        {
          needToListen = parseYesNo(i, i->first, "tcp");
        }
      else
        {
          throw ConfigFile::Error("Unrecognized option \"" + i->first + "\" in \"tcp\" section");
        }
    }

  if (!isDryRun)
    {
      shared_ptr<TcpFactory> factory = make_shared<TcpFactory>(boost::cref(port));

      using namespace boost::asio::ip;

      shared_ptr<TcpChannel> ipv4Channel = factory->createChannel("0.0.0.0", port);
      shared_ptr<TcpChannel> ipv6Channel = factory->createChannel("::", port);

      if (needToListen)
        {
          // Should acceptFailed callback be used somehow?

          ipv4Channel->listen(bind(&FaceTable::add, &m_faceTable, _1),
                              TcpChannel::ConnectFailedCallback());
          ipv6Channel->listen(bind(&FaceTable::add, &m_faceTable, _1),
                              TcpChannel::ConnectFailedCallback());
        }

      m_factories.insert(std::make_pair("tcp", factory));
      m_factories.insert(std::make_pair("tcp4", factory));
      m_factories.insert(std::make_pair("tcp6", factory));
    }
}

void
FaceManager::processSectionUdp(const ConfigSection& configSection, bool isDryRun)
{
  // ; the udp section contains settings of UDP faces and channels
  // udp
  // {
  //   port 6363 ; UDP unicast port number
  //   idle_timeout 30 ; idle time (seconds) before closing a UDP unicast face
  //   keep_alive_interval 25; interval (seconds) between keep-alive refreshes

  //   ; NFD creates one UDP multicast face per NIC
  //   mcast yes ; set to 'no' to disable UDP multicast, default 'yes'
  //   mcast_port 56363 ; UDP multicast port number
  //   mcast_group 224.0.23.170 ; UDP multicast group (IPv4 only)
  // }

  std::string port = "6363";
  size_t timeout = 30;
  size_t keepAliveInterval = 25;
  bool useMcast = true;
  std::string mcastPort = "56363";
  std::string mcastGroup;

  for (ConfigSection::const_iterator i = configSection.begin();
       i != configSection.end();
       ++i)
    {
      if (i->first == "port")
        {
          port = i->second.get_value<std::string>();
        }
      else if (i->first == "idle_timeout")
        {
          try
            {
              timeout = i->second.get_value<size_t>();
            }
          catch (const std::exception& e)
            {
              throw ConfigFile::Error("Invalid value for option \"" +
                                      i->first + "\" in \"udp\" section");
            }
        }
      else if (i->first == "keep_alive_interval")
        {
          try
            {
              keepAliveInterval = i->second.get_value<size_t>();
            }
          catch (const std::exception& e)
            {
              throw ConfigFile::Error("Invalid value for option \"" +
                                      i->first + "\" in \"udp\" section");
            }
        }
      else if (i->first == "mcast")
        {
          useMcast = parseYesNo(i, i->first, "udp");
        }
      else if (i->first == "mcast_port")
        {
          mcastPort = i->second.get_value<std::string>();
        }
      else if (i->first == "mcast_group")
        {
          using namespace boost::asio::ip;
          mcastGroup = i->second.get_value<std::string>();
          try
            {
              address mcastGroupTest = address::from_string(mcastGroup);
              if (!mcastGroupTest.is_v4())
                {
                  throw ConfigFile::Error("Invalid value for option \"" +
                                          i->first + "\" in \"udp\" section");
                }
            }
          catch(const std::runtime_error& e)
            {
              throw ConfigFile::Error("Invalid value for option \"" +
                                      i->first + "\" in \"udp\" section");
            }
        }
      else
        {
          throw ConfigFile::Error("Unrecognized option \"" + i->first + "\" in \"udp\" section");
        }
    }

  /// \todo what is keep alive interval used for?

  if (!isDryRun)
    {
      shared_ptr<UdpFactory> factory = make_shared<UdpFactory>(boost::cref(port));

      shared_ptr<UdpChannel> ipv4Channel =
        factory->createChannel("0.0.0.0", port, time::seconds(timeout));
      shared_ptr<UdpChannel> ipv6Channel =
        factory->createChannel("::", port, time::seconds(timeout));

      m_factories.insert(std::make_pair("udp", factory));
      m_factories.insert(std::make_pair("udp4", factory));
      m_factories.insert(std::make_pair("udp6", factory));

      if (useMcast)
        {
          /// \todo create one multicast face per NIC
          NFD_LOG_WARN("multicast faces are not implemented");
        }
    }
}

void
FaceManager::processSectionEther(const ConfigSection& configSection, bool isDryRun)
{
  // ; the ether section contains settings of Ethernet faces and channels
  // ether
  // {
  //   ; NFD creates one Ethernet multicast face per NIC
  //   mcast yes ; set to 'no' to disable Ethernet multicast, default 'yes'
  //   mcast_group 01:00:5E:00:17:AA ; Ethernet multicast group
  // }

  bool useMcast = true;
  std::string mcastGroup;

  for (ConfigSection::const_iterator i = configSection.begin();
       i != configSection.end();
       ++i)
    {
      if (i->first == "mcast")
        {
          useMcast = parseYesNo(i, i->first, "ether");
        }

      else if (i->first == "mcast_group")
        {
          const std::string mcastGroup = i->second.get_value<std::string>();
          /// \todo change to use ethernet::Address::fromString
          if (!ether_aton(mcastGroup.c_str()))
            {
              throw ConfigFile::Error("Invalid value for option \"" +
                                      i->first + "\" in \"ether\" section");
            }
        }
      else
        {
          throw ConfigFile::Error("Unrecognized option \"" + i->first + "\" in \"ether\" section");
        }
    }

  if (!isDryRun)
    {
      shared_ptr<EthernetFactory> factory = make_shared<EthernetFactory>();
      m_factories.insert(std::make_pair("ether", factory));

      if (useMcast)
        {
          /// \todo create one multicast face per NIC
          NFD_LOG_WARN("multicast faces are not implemented");
        }
    }
}


void
FaceManager::onFaceRequest(const Interest& request)
{
  const Name& command = request.getName();
  const size_t commandNComps = command.size();

  if (COMMAND_UNSIGNED_NCOMPS <= commandNComps &&
      commandNComps < COMMAND_SIGNED_NCOMPS)
    {
      NFD_LOG_INFO("command result: unsigned verb: " << command);
      sendResponse(command, 401, "Signature required");

      return;
    }
  else if (commandNComps < COMMAND_SIGNED_NCOMPS ||
           !COMMAND_PREFIX.isPrefixOf(command))
    {
      NFD_LOG_INFO("command result: malformed");
      sendResponse(command, 400, "Malformed command");
      return;
    }

  onValidatedFaceRequest(request.shared_from_this());
}

void
FaceManager::onValidatedFaceRequest(const shared_ptr<const Interest>& request)
{
  const Name& command = request->getName();
  const Name::Component& verb = command.get(COMMAND_PREFIX.size());

  VerbDispatchTable::const_iterator verbProcessor = m_verbDispatch.find (verb);
  if (verbProcessor != m_verbDispatch.end())
    {
      ndn::nfd::FaceManagementOptions options;
      if (!extractOptions(*request, options))
        {
          sendResponse(command, 400, "Malformed command");
          return;
        }

      /// \todo authorize command
      if (false)
        {
          NFD_LOG_INFO("command result: unauthorized verb: " << command);
          sendResponse(command, 403, "Unauthorized command");
          return;
        }

      NFD_LOG_INFO("command result: processing verb: " << verb);
      (verbProcessor->second)(this, command, options);
    }
  else
    {
      NFD_LOG_INFO("command result: unsupported verb: " << verb);
      sendResponse(command, 501, "Unsupported command");
    }

}

bool
FaceManager::extractOptions(const Interest& request,
                            ndn::nfd::FaceManagementOptions& extractedOptions)
{
  const Name& command = request.getName();
  const size_t optionCompIndex =
    COMMAND_PREFIX.size() + 1;

  try
    {
      Block rawOptions = request.getName()[optionCompIndex].blockFromValue();
      extractedOptions.wireDecode(rawOptions);
    }
  catch (const ndn::Tlv::Error& e)
    {
      NFD_LOG_INFO("Bad command option parse: " << command);
      return false;
    }
  NFD_LOG_DEBUG("Options parsed OK");
  return true;
}

void
FaceManager::onCreated(const Name& requestName,
                       ndn::nfd::FaceManagementOptions& options,
                       const shared_ptr<Face>& newFace)
{
  m_faceTable.add(newFace);
  options.setFaceId(newFace->getId());

  NFD_LOG_INFO("Created Face ID " << newFace->getId());

  ndn::nfd::ControlResponse response;
  setResponse(response, 200, "Success", options.wireEncode());
  sendResponse(requestName, response);
}

void
FaceManager::onConnectFailed(const Name& requestName, const std::string& reason)
{
  NFD_LOG_INFO("Failed to create face: " << reason);
  sendResponse(requestName, 400, "Failed to create face");
}

void
FaceManager::createFace(const Name& requestName,
                        ndn::nfd::FaceManagementOptions& options)
{
  FaceUri uri;
  if (!uri.parse(options.getUri()))
    {
      sendResponse(requestName, 400, "Malformed command");
      return;
    }

  FactoryMap::iterator factory = m_factories.find(uri.getScheme());
  if (factory == m_factories.end())
    {
      sendResponse(requestName, 501, "Unsupported protocol");
      return;
    }

  factory->second->createFace(uri,
                              bind(&FaceManager::onCreated, this, requestName, options, _1),
                              bind(&FaceManager::onConnectFailed, this, requestName, _1));
}


void
FaceManager::destroyFace(const Name& requestName,
                         ndn::nfd::FaceManagementOptions& options)
{
  shared_ptr<Face> target = m_faceTable.get(options.getFaceId());
  if (target)
    {
      m_faceTable.remove(target);
      target->close();
    }
  sendResponse(requestName, 200, "Success");
}

FaceManager::~FaceManager()
{

}

} // namespace nfd