/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2014,  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 NFD (Named Data Networking Forwarding Daemon).
 * See AUTHORS.md for complete list of NFD authors and contributors.
 *
 * NFD 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.
 *
 * NFD 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
 * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "limited-io.hpp"
#include "core/logger.hpp"

namespace nfd {
namespace tests {

NFD_LOG_INIT("LimitedIo");

const int LimitedIo::UNLIMITED_OPS = std::numeric_limits<int>::max();
const time::nanoseconds LimitedIo::UNLIMITED_TIME = time::nanoseconds::min();

LimitedIo::LimitedIo()
  : m_isRunning(false)
  , m_nOpsRemaining(0)
{
}

LimitedIo::StopReason
LimitedIo::run(int nOpsLimit, const time::nanoseconds& timeLimit)
{
  BOOST_ASSERT(!m_isRunning);

  if (nOpsLimit <= 0) {
    return EXCEED_OPS;
  }

  m_isRunning = true;

  m_reason = NO_WORK;
  m_nOpsRemaining = nOpsLimit;
  if (timeLimit >= time::nanoseconds::zero()) {
    m_timeout = scheduler::schedule(timeLimit, bind(&LimitedIo::afterTimeout, this));
  }

  try {
    getGlobalIoService().run();
  }
  catch (std::exception& ex) {
    m_reason = EXCEPTION;
    NFD_LOG_ERROR("g_io.run() exception: " << ex.what());
    m_lastException = ex;
  }

  getGlobalIoService().reset();
  scheduler::cancel(m_timeout);
  m_isRunning = false;
  return m_reason;
}

void
LimitedIo::afterOp()
{
  if (!m_isRunning) {
    // Do not proceed further if .afterOp() is invoked out of .run(),
    // because io_service.stop() without io_service.reset() would leave it unusable.
    return;
  }

  --m_nOpsRemaining;
  if (m_nOpsRemaining <= 0) {
    m_reason = EXCEED_OPS;
    getGlobalIoService().stop();
  }
}

void
LimitedIo::afterTimeout()
{
  m_reason = EXCEED_TIME;
  getGlobalIoService().stop();
}

const std::exception&
LimitedIo::getLastException() const
{
  return m_lastException;
}

} // namespace tests
} // namespace nfd