/*********************************************************************
 * Software License Agreement (BSD License)
 *
 *  Modified and adapted by
 *  Copyright (c) 2015, Autonomous Systems Lab / ETH Zurich
 *
 *  Original Copyright (c) 2008, Willow Garage, Inc.
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of Willow Garage, Inc. nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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 *********************************************************************/
/*
 *  Modified: Stefan Leutenegger (s.leutenegger@imperial.ac.uk)
 *  Modified: Andreas Forster (an.forster@gmail.com)
 */

/**
 * @file implementation/Time.hpp
 * @brief Header file for the TimeBase class.
 * @author Willow Garage Inc.
 * @author Stefan Leutenegger
 * @author Andreas Forster
 */


#ifndef INCLUDE_OKVIS_IMPLEMENTATION_TIME_HPP_
#define INCLUDE_OKVIS_IMPLEMENTATION_TIME_HPP_

/*********************************************************************
 ** Headers
 *********************************************************************/

//#include <ros/platform.h>
#include <iostream>
#include <cmath>
//#include <ros/exception.h>

/*********************************************************************
 ** Cross Platform Headers
 *********************************************************************/

#ifdef WIN32
#include <sys/timeb.h>
#else
#include <sys/time.h>
#endif

/// \brief okvis Main namespace of this package.
namespace okvis {

template<class T, class D>
T& TimeBase<T, D>::fromNSec(uint64_t t) {
  sec = (int32_t)(t / 1000000000);
  nsec = (int32_t)(t % 1000000000);

  normalizeSecNSec(sec, nsec);

  return *static_cast<T*>(this);
}

template<class T, class D>
D TimeBase<T, D>::operator-(const T &rhs) const {
  return D((int32_t) sec - (int32_t) rhs.sec,
           (int32_t) nsec - (int32_t) rhs.nsec);  // carry handled in ctor
}

template<class T, class D>
T TimeBase<T, D>::operator-(const D &rhs) const {
  return *static_cast<const T*>(this) + (-rhs);
}

template<class T, class D>
T TimeBase<T, D>::operator+(const D &rhs) const {
  int64_t sec_sum = (int64_t) sec + (int64_t) rhs.sec;
  int64_t nsec_sum = (int64_t) nsec + (int64_t) rhs.nsec;

  // Throws an exception if we go out of 32-bit range
  normalizeSecNSecUnsigned(sec_sum, nsec_sum);

  // now, it's safe to downcast back to uint32 bits
  return T((uint32_t) sec_sum, (uint32_t) nsec_sum);
}

template<class T, class D>
T& TimeBase<T, D>::operator+=(const D &rhs) {
  *this = *this + rhs;
  return *static_cast<T*>(this);
}

template<class T, class D>
T& TimeBase<T, D>::operator-=(const D &rhs) {
  *this += (-rhs);
  return *static_cast<T*>(this);
}

template<class T, class D>
bool TimeBase<T, D>::operator==(const T &rhs) const {
  return sec == rhs.sec && nsec == rhs.nsec;
}

template<class T, class D>
bool TimeBase<T, D>::operator<(const T &rhs) const {
  if (sec < rhs.sec)
    return true;
  else if (sec == rhs.sec && nsec < rhs.nsec)
    return true;
  return false;
}

template<class T, class D>
bool TimeBase<T, D>::operator>(const T &rhs) const {
  if (sec > rhs.sec)
    return true;
  else if (sec == rhs.sec && nsec > rhs.nsec)
    return true;
  return false;
}

template<class T, class D>
bool TimeBase<T, D>::operator<=(const T &rhs) const {
  if (sec < rhs.sec)
    return true;
  else if (sec == rhs.sec && nsec <= rhs.nsec)
    return true;
  return false;
}

template<class T, class D>
bool TimeBase<T, D>::operator>=(const T &rhs) const {
  if (sec > rhs.sec)
    return true;
  else if (sec == rhs.sec && nsec >= rhs.nsec)
    return true;
  return false;
}

}

#endif // INCLUDE_OKVIS_IMPLEMENTATION_TIME_HPP_

