#include "timing.h"

timespec diff(timespec start, timespec end);

#ifdef WINDOWS

// Windows timing code
LARGE_INTEGER getFILETIMEoffset()
{
  SYSTEMTIME s;
  FILETIME f;
  LARGE_INTEGER t;

  s.wYear = 1970;
  s.wMonth = 1;
  s.wDay = 1;
  s.wHour = 0;
  s.wMinute = 0;
  s.wSecond = 0;
  s.wMilliseconds = 0;
  SystemTimeToFileTime(&s, &f);
  t.QuadPart = f.dwHighDateTime;
  t.QuadPart <<= 32;
  t.QuadPart |= f.dwLowDateTime;
  return (t);
}

int clock_gettime(int X, timespec *tv)
{
  LARGE_INTEGER           t;
  FILETIME            f;
  double                  microseconds;
  static LARGE_INTEGER    offset;
  static double           frequencyToMicroseconds;
  static int              initialized = 0;
  static BOOL             usePerformanceCounter = 0;

  if (!initialized)
  {
    LARGE_INTEGER performanceFrequency;
    initialized = 1;
    usePerformanceCounter = QueryPerformanceFrequency(&performanceFrequency);
    if (usePerformanceCounter)
    {
      QueryPerformanceCounter(&offset);
      frequencyToMicroseconds = (double)performanceFrequency.QuadPart / 1000000.;
    }
    else
    {
      offset = getFILETIMEoffset();
      frequencyToMicroseconds = 10.;
    }
  }
  if (usePerformanceCounter) QueryPerformanceCounter(&t);
  else
  {
    GetSystemTimeAsFileTime(&f);
    t.QuadPart = f.dwHighDateTime;
    t.QuadPart <<= 32;
    t.QuadPart |= f.dwLowDateTime;
  }

  t.QuadPart -= offset.QuadPart;
  microseconds = (double)t.QuadPart / frequencyToMicroseconds;
  t.QuadPart = microseconds;
  tv->tv_sec = t.QuadPart / 1000000;
  tv->tv_usec = t.QuadPart % 1000000;
  return (0);
}

void getTime(timespec* time)
{
  clock_gettime(0, time);
}
double diffclock(timespec time1,timespec time2)
{
  timespec delta = diff(time1,time2);
  double milliseconds = (delta.tv_sec * 1000) +  (((double) delta.tv_usec) / 1000.0);

  return milliseconds;
}

timespec diff(timespec start, timespec end)
{
  timespec temp;
  if ((end.tv_usec-start.tv_usec)<0)
  {
    temp.tv_sec = end.tv_sec-start.tv_sec-1;
    temp.tv_usec = 1000000+end.tv_usec-start.tv_usec;
  }
  else
  {
    temp.tv_sec = end.tv_sec-start.tv_sec;
    temp.tv_usec = end.tv_usec-start.tv_usec;
  }
  return temp;
}

#else

void getTime(timespec* time)
{
#ifdef __MACH__ // OS X does not have clock_gettime, use clock_get_time
  clock_serv_t cclock;
  mach_timespec_t mts;
  host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
  clock_get_time(cclock, &mts);
  mach_port_deallocate(mach_task_self(), cclock);
  time->tv_sec = mts.tv_sec;
  time->tv_nsec = mts.tv_nsec;
#else
  clock_gettime(CLOCK_PROCESS_CPUTIME_ID, time);
#endif
}
double diffclock(timespec time1,timespec time2)
{
  timespec delta = diff(time1,time2);
  double milliseconds = (delta.tv_sec * 1000) +  (((double) delta.tv_nsec) / 1000000.0);

  return milliseconds;
}

timespec diff(timespec start, timespec end)
{
  timespec temp;
  if ((end.tv_nsec-start.tv_nsec)<0)
  {
    temp.tv_sec = end.tv_sec-start.tv_sec-1;
    temp.tv_nsec = 1000000000+end.tv_nsec-start.tv_nsec;
  }
  else
  {
    temp.tv_sec = end.tv_sec-start.tv_sec;
    temp.tv_nsec = end.tv_nsec-start.tv_nsec;
  }
  return temp;
}

#endif