/*************************************************************************

 *                                                                       *

 * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith.       *

 * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *

 *                                                                       *

 * This library is free software; you can redistribute it and/or         *

 * modify it under the terms of EITHER:                                  *

 *   (1) The GNU Lesser General Public License as published by the Free  *

 *       Software Foundation; either version 2.1 of the License, or (at  *

 *       your option) any later version. The text of the GNU Lesser      *

 *       General Public License is included with this library in the     *

 *       file LICENSE.TXT.                                               *

 *   (2) The BSD-style license that is included with this library in     *

 *       the file LICENSE-BSD.TXT.                                       *

 *                                                                       *

 * This library is distributed in the hope that it will be useful,       *

 * but WITHOUT ANY WARRANTY; without even the implied warranty of        *

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *

 * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *

 *                                                                       *

 *************************************************************************/

/*

TODO

----

* gettimeofday() and the pentium time stamp counter return the real time,

  not the process time. fix this somehow!

*/

#include <ode/common.h>

#include <ode/timer.h>

#include <ode/ode.h>

// misc defines

#define ALLOCA dALLOCA16

#include <sys/time.h>

#include <unistd.h>

static inline void getClockCount (unsigned long cc[2])

{

  struct timeval tv;

  gettimeofday (&tv,0);

  cc[0] = tv.tv_usec;

  cc[1] = tv.tv_sec;

}

static inline void serialize()

{

}

static inline double loadClockCount (unsigned long a[2])

{

  return a[1]*1.0e6 + a[0];

}

EXPORT_C double dTimerResolution()

{

  unsigned long cc1[2],cc2[2];

  getClockCount (cc1);

  do {

    getClockCount (cc2);

  }

  while (cc1[0]==cc2[0] && cc1[1]==cc2[1]);

  do {

    getClockCount (cc1);

  }

  while (cc1[0]==cc2[0] && cc1[1]==cc2[1]);

  double t1 = loadClockCount (cc1);

  double t2 = loadClockCount (cc2);

  return (t1-t2) / dTimerTicksPerSecond();

}

EXPORT_C double dTimerTicksPerSecond()

{

  return 1000000;

}

//****************************************************************************

// stop watches

EXPORT_C void dStopwatchReset (dStopwatch *s)

{

  s->time = 0;

  s->cc[0] = 0;

  s->cc[1] = 0;

}

EXPORT_C void dStopwatchStart (dStopwatch *s)

{

  serialize();

  getClockCount (s->cc);

}

EXPORT_C void dStopwatchStop  (dStopwatch *s)

{

  unsigned long cc[2];

  serialize();

  getClockCount (cc);

  double t1 = loadClockCount (s->cc);

  double t2 = loadClockCount (cc);

  s->time += t2-t1;

}

EXPORT_C double dStopwatchTime (dStopwatch *s)

{

  return s->time / dTimerTicksPerSecond();

}

//****************************************************************************

// code timers

// maximum number of events to record

// make sure all slot totals and counts reset to 0 at start

static void initSlots()

{

  static int initialized=0;

  if (!initialized) {

    for (int i=0; i<MAXNUM; i++) {

      GetGlobalData()->event[i].count = 0;

      GetGlobalData()->event[i].total_t = 0;

      GetGlobalData()->event[i].total_p = 0;

    }

    initialized = 1;

  }

}

EXPORT_C void dTimerStart (const char *description)

{

  initSlots();

  GetGlobalData()->event[0].description = const_cast<char*> (description);

  GetGlobalData()->num = 1;

  serialize();

  getClockCount (GetGlobalData()->event[0].cc);

}

EXPORT_C void dTimerNow (const char *description)

{

  if (GetGlobalData()->num < MAXNUM) {

    // do not serialize

    getClockCount (GetGlobalData()->event[GetGlobalData()->num].cc);

    GetGlobalData()->event[GetGlobalData()->num].description = const_cast<char*> (description);

    GetGlobalData()->num++;

  }

}

EXPORT_C void dTimerEnd()

{

  if (GetGlobalData()->num < MAXNUM) {

    serialize();

    getClockCount (GetGlobalData()->event[GetGlobalData()->num].cc);

    GetGlobalData()->event[GetGlobalData()->num].description = "TOTAL";

    GetGlobalData()->num++;

  }

}

//****************************************************************************

// print report

static void fprintDoubleWithPrefix (FILE *f, double a, char *fmt)

{

  if (a >= 0.999999) {

    fprintf (f,fmt,a);

    return;

  }

  a *= 1000.0;

  if (a >= 0.999999) {

    fprintf (f,fmt,a);

    fprintf (f,"m");

    return;

  }

  a *= 1000.0;

  if (a >= 0.999999) {

    fprintf (f,fmt,a);

    fprintf (f,"u");

    return;

  }

  a *= 1000.0;

  fprintf (f,fmt,a);

  fprintf (f,"n");

}

EXPORT_C void dTimerReport (FILE *fout, int average)

{

  int i;

  size_t maxl;

  double ccunit = 1.0/dTimerTicksPerSecond();

  fprintf (fout,"\nTimer Report (");

  fprintDoubleWithPrefix (fout,ccunit,"%.2f ");

  fprintf (fout,"s resolution)\n------------\n");

  if (GetGlobalData()->num < 1) return;

  // get maximum description length

  maxl = 0;

  for (i=0; i<GetGlobalData()->num; i++) {

    size_t l = strlen (GetGlobalData()->event[i].description);

    if (l > maxl) maxl = l;

  }

  // calculate total time

  double t1 = loadClockCount (GetGlobalData()->event[0].cc);

  double t2 = loadClockCount (GetGlobalData()->event[GetGlobalData()->num-1].cc);

  double total = t2 - t1;

  if (total <= 0) total = 1;

  // compute time difference for all slots except the last one. update totals

  double *times = (double*) malloc (GetGlobalData()->num * sizeof(double));

  if (times == NULL) {

  	return;

  }

  for (i=0; i < (GetGlobalData()->num-1); i++) {

    double t1 = loadClockCount (GetGlobalData()->event[i].cc);

    double t2 = loadClockCount (GetGlobalData()->event[i+1].cc);

    times[i] = t2 - t1;

    GetGlobalData()->event[i].count++;

    GetGlobalData()->event[i].total_t += times[i];

    GetGlobalData()->event[i].total_p += times[i]/total * 100.0;

  }

  // print report (with optional averages)

  for (i=0; i<GetGlobalData()->num; i++) {

    double t,p;

    if (i < (GetGlobalData()->num-1)) {

      t = times[i];

      p = t/total * 100.0;

    }

    else {

      t = total;

      p = 100.0;

    }

    fprintf (fout,"%-*s %7.2fms %6.2f%%",maxl,GetGlobalData()->event[i].description,

	     t*ccunit * 1000.0, p);

    if (average && i < (GetGlobalData()->num-1)) {

      fprintf (fout,"  (avg %7.2fms %6.2f%%)",

	       (GetGlobalData()->event[i].total_t / GetGlobalData()->event[i].count)*ccunit * 1000.0,

	       GetGlobalData()->event[i].total_p / GetGlobalData()->event[i].count);

    }

    fprintf (fout,"\n");

  }

  fprintf (fout,"\n");

  free(times);

}