/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2013-2015 Regents of the University of California,
 *                         Arizona Board of Regents,
 *                         Colorado State University,
 *                         University Pierre & Marie Curie, Sorbonne University,
 *                         Washington University in St. Louis,
 *                         Beijing Institute of Technology,
 *                         The University of Memphis.
 *
 * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
 *
 * ndn-cxx library is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * ndn-cxx library 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 Lesser General Public License for more details.
 *
 * You should have received copies of the GNU General Public License and GNU Lesser
 * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
 */

#include "util/notification-subscriber.hpp"
#include "util/notification-stream.hpp"
#include "simple-notification.hpp"
#include "util/dummy-client-face.hpp"

#include "boost-test.hpp"
#include "../unit-test-time-fixture.hpp"

namespace ndn {
namespace util {
namespace tests {

BOOST_AUTO_TEST_SUITE(UtilNotificationSubscriber)

class EndToEndFixture : public ndn::tests::UnitTestTimeFixture
{
public:
  EndToEndFixture()
    : streamPrefix("ndn:/NotificationSubscriberTest")
    , publisherFace(io)
    , notificationStream(publisherFace, streamPrefix, publisherKeyChain)
    , subscriberFace(io)
    , subscriber(subscriberFace, streamPrefix, time::seconds(1))
  {
  }

  /** \brief post one notification and deliver to subscriber
   */
  void
  deliverNotification(const std::string& msg)
  {
    publisherFace.sentData.clear();
    SimpleNotification notification(msg);
    notificationStream.postNotification(notification);

    advanceClocks(time::milliseconds(1));

    BOOST_REQUIRE_EQUAL(publisherFace.sentData.size(), 1);

    lastDeliveredSeqNo = publisherFace.sentData[0].getName().at(-1).toSequenceNumber();

    lastNotification.setMessage("");
    subscriberFace.receive(publisherFace.sentData[0]);
  }

  void
  afterNotification(const SimpleNotification& notification)
  {
    lastNotification = notification;
  }

  void
  afterTimeout()
  {
    hasTimeout = true;
  }

  void
  afterDecodeError(const Data& data)
  {
    lastDecodeErrorData = data;
  }

  /** \return true if subscriberFace has an initial request (first sent Interest)
   */
  bool
  hasInitialRequest() const
  {
    if (subscriberFace.sentInterests.empty())
      return 0;

    const Interest& interest = subscriberFace.sentInterests[0];
    return interest.getName() == streamPrefix &&
           interest.getChildSelector() == 1 &&
           interest.getMustBeFresh() &&
           interest.getInterestLifetime() == subscriber.getInterestLifetime();
  }

  /** \return sequence number of the continuation request sent from subscriberFace
   *          or 0 if there's no such request as sole sent Interest
   */
  uint64_t
  getRequestSeqNo() const
  {
    if (subscriberFace.sentInterests.size() != 1)
      return 0;

    const Interest& interest = subscriberFace.sentInterests[0];
    const Name& name = interest.getName();
    if (streamPrefix.isPrefixOf(name) &&
        name.size() == streamPrefix.size() + 1 &&
        interest.getInterestLifetime() == subscriber.getInterestLifetime())
      return name[-1].toSequenceNumber();
    else
      return 0;
  }

protected:
  Name streamPrefix;
  DummyClientFace publisherFace;
  ndn::KeyChain publisherKeyChain;
  util::NotificationStream<SimpleNotification> notificationStream;
  DummyClientFace subscriberFace;
  util::NotificationSubscriber<SimpleNotification> subscriber;
  util::signal::Connection notificationConn;

  uint64_t lastDeliveredSeqNo;

  SimpleNotification lastNotification;
  bool hasTimeout;
  Data lastDecodeErrorData;
};

BOOST_FIXTURE_TEST_CASE(EndToEnd, EndToEndFixture)
{
  BOOST_REQUIRE_EQUAL(subscriber.isRunning(), false);

  // has no effect because onNotification has no handler
  subscriber.start();
  BOOST_REQUIRE_EQUAL(subscriber.isRunning(), false);

  notificationConn = subscriber.onNotification.connect(
      bind(&EndToEndFixture::afterNotification, this, _1));
  subscriber.onTimeout.connect(bind(&EndToEndFixture::afterTimeout, this));
  subscriber.onDecodeError.connect(bind(&EndToEndFixture::afterDecodeError, this, _1));

  // not received when subscriber is not running
  this->deliverNotification("n1");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK(lastNotification.getMessage().empty());
  BOOST_CHECK_EQUAL(subscriberFace.sentInterests.size(), 0);

  subscriberFace.sentInterests.clear();
  subscriber.start();
  advanceClocks(time::milliseconds(1));
  BOOST_REQUIRE_EQUAL(subscriber.isRunning(), true);
  BOOST_CHECK(this->hasInitialRequest());

  // respond to initial request
  subscriberFace.sentInterests.clear();
  this->deliverNotification("n2");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK_EQUAL(lastNotification.getMessage(), "n2");
  BOOST_CHECK_EQUAL(this->getRequestSeqNo(), lastDeliveredSeqNo + 1);

  // respond to continuation request
  subscriberFace.sentInterests.clear();
  this->deliverNotification("n3");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK_EQUAL(lastNotification.getMessage(), "n3");
  BOOST_CHECK_EQUAL(this->getRequestSeqNo(), lastDeliveredSeqNo + 1);

  // timeout
  subscriberFace.sentInterests.clear();
  lastNotification.setMessage("");
  advanceClocks(subscriber.getInterestLifetime(), 2);
  BOOST_CHECK(lastNotification.getMessage().empty());
  BOOST_CHECK_EQUAL(hasTimeout, true);
  BOOST_CHECK(this->hasInitialRequest());

  // decode error on sequence number
  Name wrongName = streamPrefix;
  wrongName.append("%07%07");
  Data wrongData(wrongName);
  publisherKeyChain.sign(wrongData);
  subscriberFace.receive(wrongData);
  subscriberFace.sentInterests.clear();
  lastNotification.setMessage("");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK(lastNotification.getMessage().empty());
  BOOST_CHECK_EQUAL(lastDecodeErrorData.getName(), wrongName);
  BOOST_CHECK(this->hasInitialRequest());

  // decode error in payload
  subscriberFace.sentInterests.clear();
  lastNotification.setMessage("");
  this->deliverNotification("\x07n4");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK(lastNotification.getMessage().empty());
  BOOST_CHECK(this->hasInitialRequest());

  // stop if handlers are cleared
  notificationConn.disconnect();
  subscriberFace.sentInterests.clear();
  this->deliverNotification("n5");
  advanceClocks(time::milliseconds(1));
  BOOST_CHECK_EQUAL(subscriberFace.sentInterests.size(), 0);
}

BOOST_AUTO_TEST_SUITE_END()

} // namespace tests
} // namespace util
} // namespace ndn