#include <limits>

#include "EpochCounter.h"

volatile EpochCounter::Epoch EpochCounter::_currentEpoch = 0;

EpochCounter::Epoch EpochCounter::getNextEpoch()
{
  return __sync_add_and_fetch(&_currentEpoch, 1);
}

time_t EpochCounter::restartAt(Epoch epoch) const
{
  std::map< Epoch, time_t >::const_iterator it =
    _startAfter.upper_bound(epoch);
  if (it == _startAfter.end())
    return std::numeric_limits< time_t >::max();
  else
    return it->second;
}

void EpochCounter::addEpoch(time_t time)
{
  while (true)
    {
      std::map< Epoch, time_t >::reverse_iterator it = _startAfter.rbegin();
      if (it == _startAfter.rend())
	break;
      if (it->second < time)
	break;
      it++;
      _startAfter.erase(it.base());
    }
  _startAfter[getNextEpoch()] = time;
}

EpochCounter::Epoch EpochCounter::getEpoch()
{
  return _currentEpoch;
}