/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2014-2024,  The University of Memphis
 *
 * This file is part of PSync.
 * See AUTHORS.md for complete list of PSync authors and contributors.
 *
 * PSync 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.
 *
 * PSync 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 a copy of the GNU Lesser General Public License along with
 * PSync, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <PSync/full-producer.hpp>

#include <ndn-cxx/face.hpp>
#include <ndn-cxx/security/key-chain.hpp>
#include <ndn-cxx/util/logger.hpp>
#include <ndn-cxx/util/random.hpp>
#include <ndn-cxx/util/scheduler.hpp>

#include <iostream>

NDN_LOG_INIT(examples.FullSyncApp);

using namespace ndn::time_literals;

class Producer
{
public:
  /**
   * @brief Initialize producer and schedule updates.
   *
   * Use default IBF size of 6 as we're expecting 6 updates to IBF in a sync cycle.
   * Set syncInterestLifetime and syncDataFreshness to 1.6 seconds.
   * userPrefix is the prefix string of user node prefixes.
   */
  Producer(const ndn::Name& syncPrefix, const std::string& userPrefix,
           int numDataStreams, int maxNumPublish)
    : m_producer(m_face, m_keyChain, syncPrefix, [this] {
          psync::FullProducer::Options opts;
          opts.onUpdate = std::bind(&Producer::processSyncUpdate, this, _1);
          opts.syncInterestLifetime = 1600_ms;
          opts.syncDataFreshness = 1600_ms;
          return opts;
      } ())
    , m_maxNumPublish(maxNumPublish)
  {
    // Add user prefixes and schedule updates for them in specified interval.
    for (int i = 0; i < numDataStreams; i++) {
      ndn::Name prefix(userPrefix + "-" + std::to_string(i));
      m_producer.addUserNode(prefix);
      m_scheduler.schedule(ndn::time::milliseconds(m_uniformRand(m_rng)),
                           [this, prefix] { doUpdate(prefix); });
    }
  }

  void
  run()
  {
    m_face.processEvents();
  }

private:
  void
  doUpdate(const ndn::Name& prefix)
  {
    m_producer.publishName(prefix);

    uint64_t seqNo = m_producer.getSeqNo(prefix).value();
    NDN_LOG_INFO("Publish: " << prefix << "/" << seqNo);

    if (seqNo < m_maxNumPublish) {
      m_scheduler.schedule(ndn::time::milliseconds(m_uniformRand(m_rng)),
                           [this, prefix] { doUpdate(prefix); });
    }
  }

  void
  processSyncUpdate(const std::vector<psync::MissingDataInfo>& updates)
  {
    for (const auto& update : updates) {
      for (uint64_t i = update.lowSeq; i <= update.highSeq; i++) {
        NDN_LOG_INFO("Update " << update.prefix << "/" << i);
      }
    }
  }

private:
  ndn::Face m_face;
  ndn::KeyChain m_keyChain;
  ndn::Scheduler m_scheduler{m_face.getIoContext()};

  psync::FullProducer m_producer;
  uint64_t m_maxNumPublish;

  ndn::random::RandomNumberEngine& m_rng{ndn::random::getRandomNumberEngine()};
  std::uniform_int_distribution<> m_uniformRand{0, 60000};
};

int
main(int argc, char* argv[])
{
  if (argc != 5) {
    std::cerr << "Usage: " << argv[0] << " <sync-prefix> <user-prefix> "
              << "<number-of-user-prefixes> <max-number-of-updates-per-user-prefix>\n";
    return 1;
  }

  try {
    Producer producer(argv[1], argv[2], std::stoi(argv[3]), std::stoi(argv[4]));
    producer.run();
  }
  catch (const std::exception& e) {
    NDN_LOG_ERROR(e.what());
  }
}