/*
 * Project: MoleCuilder
 * Description: creates and alters molecular systems
 * Copyright (C)  2010 University of Bonn. All rights reserved.
 * Please see the LICENSE file or "Copyright notice" in builder.cpp for details.
 */

/*
 * Chronos.cpp
 *
 *  Created on: Mar 14, 2011
 *      Author: heber
 */

// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

//#include "CodePatterns/MemDebug.hpp"

#include <iostream>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#ifdef HAVE_SYS_TIMES_H
# include <sys/times.h>
#else
# include <time.h>
#endif
#else
# include <time.h>
#endif


#include "CodePatterns/Chronos.hpp"

#include "CodePatterns/Singleton_impl.hpp"

Chronos::Chronos()
{
  // get time and store it internally as base time
#ifdef HAVE_TIME_H
  clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &basetime);
#else
#ifdef HAVE_SYS_TIME_H
  struct timezone timezone1;
  gettimeofday(&basetime, &timezone1);
#else
#ifdef HAVE_SYS_TIMES_H
  struct tms *basetime = new tms;
  times(basetime);
#endif
#endif
#endif
}

Chronos::~Chronos()
{
#ifndef HAVE_TIME_H
#ifndef HAVE_SYS_TIME_H
#ifdef HAVE_SYS_TIMES_H
  delete basetime;
#endif
#endif
#endif
}

double Chronos::getTime(const std::string &_name) const
{
  // only those functions have a time that have run already
  if (AccountedTime.count(_name) != 0) {
    // return -1 if function is currently running
    if (StartingTime.count(_name) == 0.)
      return AccountedTime.at(_name);
    else
      return -1.;
  }
  return 0.;
}

void Chronos::resetTime(const std::string &_name)
{
  // set accounted time to zero
  if (AccountedTime.count(_name) != 0) {
    AccountedTime[_name] = 0.;
  }
  // and end if it's currently running
  StartingTime.erase(_name);
  RecursionMap.erase(_name);
}

void Chronos::startTiming(const std::string &_name)
{
  // start time keeping
  if ((RecursionMap.count(_name) == 0) || (RecursionMap[_name] == 0)) {
    StartingTime[_name] = getCurrentTime();
    RecursionMap[_name] = 1;
  } else {
    ++RecursionMap[_name];
  }
}

double Chronos::calculateCorrectTimeDifference(
    const sec_ncsec_t &_time1,
    const sec_ncsec_t &_time2)
{
	double currenttime = 0.;
  if (_time1.second < _time2.second)
		currenttime = (_time1.first - _time2.first - 1)
			+ (1e9 + _time1.second - _time2.second) * 1.e-9;
  else
		currenttime = (_time1.first - _time2.first)
			+ (_time1.second - _time2.second) * 1.e-9;
  return currenttime;
}

double Chronos::getCurrentTime() const
{
#ifdef HAVE_TIME_H
  // clock_gettime gives nanoseconds accuracy
  timespec time1;
  clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time1);
  double currenttime = calculateCorrectTimeDifference(
		  std::make_pair( time1.tv_sec, time1.tv_nsec),
		  std::make_pair( basetime.tv_sec, basetime.tv_nsec)
		  );
#else
#ifdef HAVE_SYS_TIME_H
  struct timezone timezone1;
  timeval time1;
  // gettimeofday gives microseconds accuracy
  gettimeofday(&time1, &timezone1);
  double currenttime = calculateCorrectTimeDifference(
      std::make_pair( time1.tv_sec, time1.tv_usec),
		  std::make_pair( basetime.tv_sec, basetime.tv_usec)
		  );
#else
#ifdef HAVE_SYS_TIMES_H
  // clock is only accurate up to milliseconds
  struct tms *buffer = new tms;
  if (times(buffer) != (clock_t)(-1))
    currenttime =
        (double)(buffer->tms_utime - basetime->tms_utime)/(double)sysconf(_SC_CLK_TCK);
  else
    currenttime = 0.;
  delete buffer;
#else
  // no time keeping possible
  const double currenttime = 0.;
#endif
#endif
#endif
  //std::cout << "Current time is " << currenttime << std::endl;
  return currenttime;
}

void Chronos::endTiming(const std::string &_name)
{
  // check whether we are the topmost function, return if not
  if (--RecursionMap[_name] != 0)
    return;

  // if present
  ASSERT(StartingTime.count(_name), "Chronos::endTiming() - no timer under "
      +_name+" running.");
  ASSERT(RecursionMap.count(_name), "Chronos::endTiming() - negative recursion level for "
      +_name+".");

  // finish time keeping
  const double endtime = getCurrentTime();
  const double starttime = StartingTime[_name];
  const double RunTime = ((double)endtime - starttime);
  if (AccountedTime.count(_name) != 0)
    AccountedTime[_name] += RunTime;
  else
    AccountedTime[_name] = RunTime;

  // and zero for next run
  StartingTime.erase(_name);
}

double Chronos::SumUpTotalTime() const
{
  double sum = 0.;
  for (TimekeepingMap::const_iterator iter = AccountedTime.begin();
      iter != AccountedTime.end();
      ++iter) {
    sum += iter->second;
  }
  return sum;
}

size_t Chronos::SumUpTotalFunctions() const
{
  return AccountedTime.size();
}

std::ostream& operator<<(std::ostream &ost, const Chronos &_time)
{
  ost << "List of functions present:" << std::endl;
  for (Chronos::TimekeepingMap::const_iterator iter = _time.AccountedTime.begin();
      iter != _time.AccountedTime.end();
      ++iter)
    ost << "\t" << iter->first << "\t" << iter->second << "s" << std::endl;
  ost << "Total time passed: " << _time.SumUpTotalTime() << std::endl;
  ost << "Total functions: " << _time.SumUpTotalFunctions() << std::endl;
  return ost;
}

// construct the remainder of the singleton
CONSTRUCT_SINGLETON(Chronos)

// catch if someone wants to use Info objects in here
#ifdef INFO_HPP_
BOOST_PP_ASSERT_MSG(1,\
  ERROR: This is a safety measure to generate a compiler warning\n \
  if you really try to use info.hpp in __FILE__.)
#endif