/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2014, Regents of the University of California.
 *
 * This file is part of NDNS (Named Data Networking Domain Name Service).
 * See AUTHORS.md for complete list of NDNS authors and contributors.
 *
 * NDNS is free software: you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later version.
 *
 * NDNS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * NDNS, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef NAME_RESOLVER_HPP
#define NAME_RESOLVER_HPP

#include <boost/asio.hpp>
#include <boost/noncopyable.hpp>

#include <ndn-cxx/face.hpp>
#include <ndn-cxx/name.hpp>
#include <ndn-cxx/security/key-chain.hpp>

#include "zone.hpp"
#include "db/zone-mgr.hpp"
#include "db/rr-mgr.hpp"
#include "query.hpp"
#include "response.hpp"
#include "rr.hpp"
#include "iterative-query.hpp"
#include "iterative-query-with-forwarding-hint.hpp"
#include "ndn-app.hpp"

using namespace std;

namespace ndn {
namespace ndns {

template <class IQStrategy> //IQ stands for iterative Query Strategy
class NameCachingResolver: public NDNApp
{

public:

  NameCachingResolver(const char *programName, const char *prefix);

  void
  resolve(IQStrategy& iq);

  using NDNApp::onData;
  void
  onData(const Interest& interest, Data &data, IQStrategy& iq);

  void
  onInterest(const Name &name, const Interest &interest);

  using NDNApp::onTimeout;
  void
  onTimeout(const Interest& interest, IQStrategy& iq);

  void
  run();

  const Name& getRootZoneFowardingHint() const
  {
    return m_rootZoneFowardingHint;
  }

  void setRootZoneFowardingHint(const Name& rootZoneFowardingHint)
  {
    m_rootZoneFowardingHint = rootZoneFowardingHint;
  }

private:
  /**
   * 0 means disable forwarding hint,
   * 1 means enable forwarding hint
   * todo: 2, retrieve name and hint of the name server as a optimization way
   */

  Name m_rootZoneFowardingHint;

};


template <typename IQStrategy>
NameCachingResolver<IQStrategy>::NameCachingResolver(const char *programName,
    const char *prefix)
  : NDNApp(programName, prefix)
  , m_rootZoneFowardingHint("/")
{
  this->setInterestLifetime(time::milliseconds(2000));
}

template <class IQStrategy> void
NameCachingResolver<IQStrategy>::run()
{
  boost::asio::signal_set signalSet(m_ioService, SIGINT, SIGTERM);
  signalSet.async_wait(boost::bind(&NDNApp::signalHandler, this));
  // boost::bind(&NdnTlvPingServer::signalHandler, this)

  Name name(m_prefix);
  name.append(Query::toString(Query::QUERY_DNS_R));

  m_face.setInterestFilter(name,
      bind(&NameCachingResolver::onInterest, this, _1, _2),
      bind(&NDNApp::onRegisterFailed, this, _1, _2));

  std::cout << "\n=== NDNS Resolver " << m_programName
      << " with routeble prefix " << name.toUri() << " starts";

  if (this->m_enableForwardingHint > 0) {
    std::cout<<" & Root Zone ForwardingHint "<<this->m_rootZoneFowardingHint.toUri();
  }
  std::cout<<"==="<< std::endl;

  try {
    m_face.processEvents();
  } catch (std::exception& e) {
    std::cerr << "ERROR: " << e.what() << std::endl;
    m_hasError = true;
    m_ioService.stop();
  }
}
template <class IQStrategy> void
NameCachingResolver<IQStrategy>::onData(const Interest& interest, Data &data, IQStrategy& iq)
{
  /*
  if (interest.getName() != iq.getLastInterest().getName()) {
    std::cout << iq << std::endl;
    std::cout << "waiting for " << iq.getLastInterest().getName().toUri()
        << std::endl;
    std::cout << "coming data " << data.getName().toUri() << std::endl;
    return;
  }*/

  iq.doData(data);

  if (iq.getStep() == IterativeQuery::AnswerStub) {
    Data data = iq.getLastResponse().toData();
    Name name = iq.getQuery().getAuthorityZone();
    name.append(Query::toString(iq.getQuery().getQueryType()));
    name.append(iq.getQuery().getRrLabel());
    name.append(RR::toString(iq.getQuery().getRrType()));
    name.appendVersion();
    data.setName(name);
    data.setFreshnessPeriod(iq.getLastResponse().getFreshness());

    m_keyChain.sign(data);
    m_face.put(data);
    std::cout << "[* <- *] answer Response ("
        << Response::toString(iq.getLastResponse().getResponseType())
        << ") to stub:" << std::endl;
    std::cout << iq.getLastResponse() << std::endl;
    for (int i = 0; i < 15; i++) {
      std::cout << "----";
    }
    std::cout << std::endl << std::endl;

    //iq.setStep(IterativeQuery::FinishedSuccessfully);

  } else if (iq.getStep() == IterativeQuery::NSQuery) {
    resolve(iq);
  } else if (iq.getStep() == IterativeQuery::RRQuery) {
    resolve(iq);
  } else if (iq.getStep() == IterativeQuery::Abort) {
    return;
  } else if (iq.getStep() == IterativeQuery::FHQuery) {
    resolve(iq);
  }
  else {
    std::cout << "let me see the current step="
        << IterativeQuery::toString(iq.getStep()) << std::endl;
    std::cout << iq;
    std::cout<<std::endl;
  }

}

template <class IQStrategy> void
NameCachingResolver<IQStrategy>::onInterest(const Name &name, const Interest &interest)
{
  Query query;
  query.fromInterest(interest);
  std::cout << "[* -> *] receive Interest: " << interest.getName().toUri()
      << std::endl;
  if (query.getQueryType() == Query::QUERY_DNS) {
    cout << m_programName << " is not in charge of Query_DNS" << endl;
  }

  IQStrategy iq(query);

  if (this->m_enableForwardingHint == 0) {

  } else if (this->m_enableForwardingHint > 0) {
    //std::cout<<"--------------------create a Forwarding Hint"<<std::endl;
    IterativeQueryWithFowardingHint& iqfh =dynamic_cast<IterativeQueryWithFowardingHint&>(iq);
    iqfh.setForwardingHint(this->m_rootZoneFowardingHint);
    iqfh.setLastForwardingHint(this->m_rootZoneFowardingHint);
  }
  resolve(iq);
}

template <class IQStrategy> void
NameCachingResolver<IQStrategy>::onTimeout(const Interest& interest, IQStrategy& iq)
{
  std::cout << "[* !! *] timeout Interest " << interest.getName().toUri()
      << " timeouts" << std::endl;

  iq.doTimeout();
}

template <class IQStrategy>
void NameCachingResolver<IQStrategy>::resolve(IQStrategy& iq)
{

  Interest interest = iq.toLatestInterest();

  //must be set before express interest,since the call will back call iq
  //if set after, then the iq in call of onData will return nothing
  //be very careful here,  as a new guy to c++

  interest.setInterestLifetime(this->getInterestLifetime());
  iq.setLastInterest(interest);
  /*
  if (this->m_enableForwardingHint > 0)
  {
    //iq = (IterativeQueryWithFowardingHint)iq;
    iq = dynamic_cast<IterativeQueryWithFowardingHint>iq;
  }
  */
  std::cout<<"lastInterest="<<iq.getLastInterest()<<std::endl;

  try {
    m_face.expressInterest(interest,
        boost::bind(&NameCachingResolver::onData, this, _1, _2, iq),
        boost::bind(&NameCachingResolver::onTimeout, this, _1,  iq));
        //boost::bind(&NameCachingResolver::onData, this, _1, _2, ndn::ref(iq)),
        //boost::bind(&NameCachingResolver::onTimeout, this, _1, iq));
  } catch (std::exception& e) {
    std::cerr << "ERROR: " << e.what() << std::endl;
  }

  std::cout << "[* <- *] send Interest: " << interest.getName().toUri()
      << std::endl;
  std::cout << iq << std::endl;
}
} /* namespace ndns */
} /* namespace ndn */

#endif /* NAME_RESOLVER_HPP_ */