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

#define EFL_LOOP_PROTECTED

#include <stdlib.h>
#include <sys/time.h>

#if defined(__APPLE__) && defined(__MACH__)
# include <mach/mach_time.h>
#endif

#include <time.h>

#ifdef _WIN32
# include <evil_private.h> /* gettimeofday */
#endif

#include "Ecore.h"
#include "ecore_private.h"

#if defined(_WIN32)
static LONGLONG _ecore_time_freq;
#elif defined (HAVE_CLOCK_GETTIME)
static clockid_t _ecore_time_clock_id;
static Eina_Bool _ecore_time_got_clock_id = EINA_FALSE;
#elif defined(__APPLE__) && defined(__MACH__)
static double _ecore_time_clock_conversion = 1e-9;
#endif

EAPI double
ecore_time_get(void)
{
#ifdef _WIN32
   LARGE_INTEGER count;

   QueryPerformanceCounter(&count);
   return (double)count.QuadPart/ (double)_ecore_time_freq;
#elif defined (HAVE_CLOCK_GETTIME)
   struct timespec t;

   if (EINA_UNLIKELY(!_ecore_time_got_clock_id))
     return ecore_time_unix_get();

   if (EINA_UNLIKELY(clock_gettime(_ecore_time_clock_id, &t)))
     {
        CRI("Cannot get current time");
        return 0.0;
     }

   return (double)t.tv_sec + (((double)t.tv_nsec) / 1000000000.0);
#elif defined(__APPLE__) && defined(__MACH__)
   return _ecore_time_clock_conversion * (double)mach_absolute_time();
#else
   return ecore_time_unix_get();
#endif
}

EAPI double
ecore_time_unix_get(void)
{
#ifdef HAVE_GETTIMEOFDAY
   struct timeval timev;

   gettimeofday(&timev, NULL);
   return (double)timev.tv_sec + (((double)timev.tv_usec) / 1000000);
#else
# error "Your platform isn't supported yet"
#endif
}

EAPI double
ecore_loop_time_get(void)
{
   return efl_loop_time_get(ML_OBJ);
}

EAPI void
ecore_loop_time_set(double t)
{
   efl_loop_time_set(ML_OBJ, t);
}

/*-********************   Internal methods   ********************************/

/* TODO: Documentation says "All  implementations  support  the  system-wide
 * real-time clock, which is identified by CLOCK_REALTIME. Check if the fallback
 * to unix time (without specifying the resolution) might be removed
 */
void
_ecore_time_init(void)
{
#if defined(_WIN32)
   LARGE_INTEGER freq;

   QueryPerformanceFrequency(&freq);
   _ecore_time_freq = freq.QuadPart;
#elif defined(HAVE_CLOCK_GETTIME)
   struct timespec t;

   if (_ecore_time_got_clock_id) return;

   if (!clock_gettime(CLOCK_MONOTONIC, &t))
     {
        _ecore_time_clock_id = CLOCK_MONOTONIC;
        _ecore_time_got_clock_id = EINA_TRUE;
        DBG("using CLOCK_MONOTONIC");
     }
   else if (!clock_gettime(CLOCK_REALTIME, &t))
     {
        // may go backwards
        _ecore_time_clock_id = CLOCK_REALTIME;
        _ecore_time_got_clock_id = EINA_TRUE;
        WRN("CLOCK_MONOTONIC not available. Fallback to CLOCK_REALTIME");
     }
   else
     CRI("Cannot get a valid clock_gettime() clock id! Fallback to unix time");
#else
# if defined(__APPLE__) && defined(__MACH__)
   mach_timebase_info_data_t info;
   kern_return_t err = mach_timebase_info(&info);
   if (err == 0)
     _ecore_time_clock_conversion = 1e-9 * (double)info.numer / (double)info.denom;
   else
     WRN("Unable to get timebase info. Fallback to nanoseconds");
# else
#  warning "Your platform isn't supported yet"
   CRI("Platform does not support clock_gettime. Fallback to unix time");
# endif
#endif
   ecore_loop_time_set(ecore_time_get());
}