/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkTimerLog.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkTimerLog - Maintains timing table for performance analysis
// .SECTION Description
// vtkTimerLog contains walltime and cputime measurements associated
// with a given event.  These results can be later analyzed when
// "dumping out" the table.
//
// In addition, vtkTimerLog allows the user to simply get the current
// time, and to start/stop a simple timer separate from the timing
// table logging.

#include "vtkTimerLog.h"

#include <stdarg.h>  // Needed for ...

#ifndef _WIN32
#include <climits>     // for CLK_TCK
#include <sys/time.h>
#include <unistd.h>
#endif

#ifndef _WIN32_WCE
#include <sys/types.h>
#include <ctime>
#endif
#include "vtkObjectFactory.h"

vtkStandardNewMacro(vtkTimerLog);

// Create a singleton to cleanup the table.  No other singletons
// should be using the timer log, so it is safe to do this without the
// full ClassInitialize/ClassFinalize idiom.
class vtkTimerLogCleanup
{
public:
  ~vtkTimerLogCleanup()
    {
    vtkTimerLog::CleanupLog();
    }
};
static vtkTimerLogCleanup vtkTimerLogCleanupInstance;

// initialze the class variables
int vtkTimerLog::Logging = 1;
int vtkTimerLog::Indent = 0;
int vtkTimerLog::MaxEntries = 100;
int vtkTimerLog::NextEntry = 0;
int vtkTimerLog::WrapFlag = 0;
vtkTimerLogEntry *vtkTimerLog::TimerLog = NULL;

#ifdef CLK_TCK
int vtkTimerLog::TicksPerSecond = CLK_TCK;
#else
int vtkTimerLog::TicksPerSecond = 60;
#endif

#ifndef CLOCKS_PER_SEC
#define CLOCKS_PER_SEC (vtkTimerLog::TicksPerSecond)
#endif


#ifdef _WIN32
#ifndef _WIN32_WCE
timeb vtkTimerLog::FirstWallTime;
timeb vtkTimerLog::CurrentWallTime;
#else
FILETIME vtkTimerLog::FirstWallTime;
FILETIME vtkTimerLog::CurrentWallTime;
#endif
#else
timeval vtkTimerLog::FirstWallTime;
timeval vtkTimerLog::CurrentWallTime;
tms     vtkTimerLog::FirstCpuTicks;
tms     vtkTimerLog::CurrentCpuTicks;
#endif

//----------------------------------------------------------------------------
// Allocate timing table with MaxEntries elements.
void vtkTimerLog::AllocateLog()
{
  delete [] vtkTimerLog::TimerLog;
  vtkTimerLog::TimerLog = new vtkTimerLogEntry[vtkTimerLog::MaxEntries];
}

//----------------------------------------------------------------------------
// Remove timer log.
void vtkTimerLog::CleanupLog()
{
  if ( !vtkTimerLog::TimerLog )
    {
    return;
    }
  delete [] vtkTimerLog::TimerLog;
  vtkTimerLog::TimerLog = 0;
}

//----------------------------------------------------------------------------
// Clear the timing table.  walltime and cputime will also be set
// to zero when the first new event is recorded.
void vtkTimerLog::ResetLog()
{
  vtkTimerLog::WrapFlag = 0;
  vtkTimerLog::NextEntry = 0;
  // may want to free TimerLog to force realloc so
  // that user can resize the table by changing MaxEntries.
}


//----------------------------------------------------------------------------
// Record a timing event.  The event is represented by a formatted
// string.
void vtkTimerLog::FormatAndMarkEvent(const char *format, ...)
{
  if (! vtkTimerLog::Logging)
    {
    return;
    }

  static  char event[4096];
  va_list var_args;
  va_start(var_args, format);
  vsprintf(event, format, var_args);
  va_end(var_args);

  vtkTimerLog::MarkEvent(event);
}


//----------------------------------------------------------------------------
// Record a timing event and capture walltime and cputicks.
void vtkTimerLog::MarkEvent(const char *event)
{
  if (! vtkTimerLog::Logging)
    {
    return;
    }

  int strsize;
  double time_diff;
  int ticks_diff;

  strsize = (strlen(event)) > VTK_LOG_EVENT_LENGTH - 1
    ? VTK_LOG_EVENT_LENGTH-1 : static_cast<int>(strlen(event));

  // If this the first event we're recording, allocate the
  // internal timing table and initialize WallTime and CpuTicks
  // for this first event to zero.
  if (vtkTimerLog::NextEntry == 0 && ! vtkTimerLog::WrapFlag)
    {
    if (vtkTimerLog::TimerLog == NULL)
      {
      vtkTimerLog::AllocateLog();
      }

#ifdef _WIN32
#ifdef _WIN32_WCE
    SYSTEMTIME st;
    GetLocalTime(&st);
    SystemTimeToFileTime(&st, &(vtkTimerLog::FirstWallTime));
#else
    ::ftime( &(vtkTimerLog::FirstWallTime) );
#endif
#else
    gettimeofday( &(vtkTimerLog::FirstWallTime), NULL );
    times(&FirstCpuTicks);
#endif

    vtkTimerLog::TimerLog[0].Indent = vtkTimerLog::Indent;
    vtkTimerLog::TimerLog[0].WallTime = 0.0;
    vtkTimerLog::TimerLog[0].CpuTicks = 0;
    strncpy(vtkTimerLog::TimerLog[0].Event, event, strsize);
    vtkTimerLog::TimerLog[0].Event[strsize] = '\0';
    vtkTimerLog::NextEntry = 1;
    return;
    }

#ifdef _WIN32
#ifdef _WIN32_WCE
    SYSTEMTIME st;
    GetLocalTime(&st);
    SystemTimeToFileTime(&st, &(vtkTimerLog::CurrentWallTime));
    time_diff = (vtkTimerLog::CurrentWallTime.dwHighDateTime -
      vtkTimerLog::FirstWallTime.dwHighDateTime);
    time_diff = time_diff * 429.4967296;
    time_diff = time_diff + ((vtkTimerLog::CurrentWallTime.dwLowDateTime -
      vtkTimerLog::FirstWallTime.dwLowDateTime) / 10000000.0);
#else
  static double scale = 1.0/1000.0;
  ::ftime( &(vtkTimerLog::CurrentWallTime) );
  time_diff =
    vtkTimerLog::CurrentWallTime.time - vtkTimerLog::FirstWallTime.time;
  time_diff +=
    (vtkTimerLog::CurrentWallTime.millitm
     - vtkTimerLog::FirstWallTime.millitm) * scale;
#endif
  ticks_diff = 0;
#else
  static double scale = 1.0/1000000.0;
  gettimeofday( &(vtkTimerLog::CurrentWallTime), NULL );
  time_diff  =  vtkTimerLog::CurrentWallTime.tv_sec
    - vtkTimerLog::FirstWallTime.tv_sec;
  time_diff +=
    (vtkTimerLog::CurrentWallTime.tv_usec
     - vtkTimerLog::FirstWallTime.tv_usec) * scale;

  times(&CurrentCpuTicks);
  ticks_diff = (CurrentCpuTicks.tms_utime + CurrentCpuTicks.tms_stime) -
                (FirstCpuTicks.tms_utime + FirstCpuTicks.tms_stime);
#endif

  vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].Indent = vtkTimerLog::Indent;
  vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].WallTime =
    static_cast<double>(time_diff);
  vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].CpuTicks = ticks_diff;
  strncpy(vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].Event, event, strsize);
  vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].Event[strsize] = '\0';

  vtkTimerLog::NextEntry++;
  if (vtkTimerLog::NextEntry == vtkTimerLog::MaxEntries)
    {
    vtkTimerLog::NextEntry = 0;
    vtkTimerLog::WrapFlag = 1;
    }
}


//----------------------------------------------------------------------------
// Record a timing event and capture walltime and cputicks.
// Increments indent after mark.
void vtkTimerLog::MarkStartEvent(const char *event)
{
  if (! vtkTimerLog::Logging)
    { // Maybe we should still change the Indent ...
    return;
    }

  vtkTimerLog::MarkEvent(event);
  ++vtkTimerLog::Indent;
}

//----------------------------------------------------------------------------
// Record a timing event and capture walltime and cputicks.
// Decrements indent after mark.
void vtkTimerLog::MarkEndEvent(const char *event)
{
  if (! vtkTimerLog::Logging)
    { // Maybe we should still change the Indent ...
    return;
    }

  vtkTimerLog::MarkEvent(event);
  --vtkTimerLog::Indent;
}

//----------------------------------------------------------------------------
// Record a timing event and capture walltime and cputicks.
int vtkTimerLog::GetNumberOfEvents()
{
  if (vtkTimerLog::WrapFlag)
    {
    return vtkTimerLog::MaxEntries;
    }
   else
    {
    return vtkTimerLog::NextEntry;
    }
}


//----------------------------------------------------------------------------
vtkTimerLogEntry *vtkTimerLog::GetEvent(int idx)
{
  int num = vtkTimerLog::GetNumberOfEvents();
  int start = 0;
  if (vtkTimerLog::WrapFlag)
    {
    start = vtkTimerLog::NextEntry;
    }

  if (idx < 0 || idx >= num)
    {
    cerr << "Bad entry index.";
    return NULL;
    }
  idx = (idx + start) % vtkTimerLog::MaxEntries;

  return vtkTimerLog::TimerLog + idx;
}


//----------------------------------------------------------------------------
int vtkTimerLog::GetEventIndent(int idx)
{
  vtkTimerLogEntry *tmp = vtkTimerLog::GetEvent(idx);

  if (tmp)
    {
    return tmp->Indent;
    }
  else
    {
    return 0;
    }
}

//----------------------------------------------------------------------------
double vtkTimerLog::GetEventWallTime(int idx)
{
  vtkTimerLogEntry *tmp = vtkTimerLog::GetEvent(idx);

  if (tmp)
    {
    return tmp->WallTime;
    }
  else
    {
    return 0.0;
    }
}

//----------------------------------------------------------------------------
const char* vtkTimerLog::GetEventString(int idx)
{
  vtkTimerLogEntry *tmp = vtkTimerLog::GetEvent(idx);

  if (tmp)
    {
    return tmp->Event;
    }
  else
    {
    return NULL;
    }
}


//----------------------------------------------------------------------------
// Write the timing table out to a file.  Calculate some helpful
// statistics (deltas and  percentages) in the process.
void vtkTimerLog::DumpLogWithIndents(ostream *os, double threshold)
{
#ifndef _WIN32_WCE
  int num;
  int i1, i2, j;
  int indent1;
  int nextIndent;
  double dtime;

  num = vtkTimerLog::GetNumberOfEvents();

  for (i1=0; i1 < num; i1++)
    {
    indent1 = vtkTimerLog::GetEventIndent(i1);

    // Search for an end event.
    i2 = i1 + 1;
    while (i2 < num && vtkTimerLog::GetEventIndent(i2) > indent1)
      { // This was a start event.
      ++i2;
      }
    // If the next indent is smaller, then the event should be an end event.
    if (i2 == num)
      {
      nextIndent = vtkTimerLog::Indent;
      }
    else
      {
      nextIndent = vtkTimerLog::GetEventIndent(i2);
      }

    // Backup one to get the end event.
    --i2;

    // Simple events and end events will have dtime of 0.
    dtime = vtkTimerLog::GetEventWallTime(i2) - vtkTimerLog::GetEventWallTime(i1);
    if (nextIndent == indent1)
      { // not an end event
      if (dtime >= threshold || i2 == i1)
        { // start event past threshold or singleton event.
        // Print the indent.
        j = indent1;
        while (j-- > 0)
          {
          *os << "    ";
          }
        *os << vtkTimerLog::GetEventString(i1);
        if (i2 > i1)
          { // Start event.
          *os << ",  " << dtime << " seconds\n";
          }
        else
          { // Singlton event.
          *os << endl;
          }
        }
      }
    }

#endif
}

//----------------------------------------------------------------------------
// Write the timing table out to a file.  Calculate some helpful
// statistics (deltas and  percentages) in the process.
void vtkTimerLog::DumpLog(const char *filename)
{
#ifndef _WIN32_WCE
  ofstream os_with_warning_C4701(filename);
  int i;

  if ( vtkTimerLog::WrapFlag )
    {
    vtkTimerLog::DumpEntry(os_with_warning_C4701, 0,
                    vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].WallTime, 0,
                    vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].CpuTicks, 0,
                    vtkTimerLog::TimerLog[vtkTimerLog::NextEntry].Event);
    for (i=vtkTimerLog::NextEntry+1; i<vtkTimerLog::MaxEntries; i++)
      {
      vtkTimerLog::DumpEntry(os_with_warning_C4701,
                i-vtkTimerLog::NextEntry, vtkTimerLog::TimerLog[i].WallTime,
                vtkTimerLog::TimerLog[i].WallTime
                 - vtkTimerLog::TimerLog[i-1].WallTime,
                vtkTimerLog::TimerLog[i].CpuTicks,
                vtkTimerLog::TimerLog[i].CpuTicks
                 - vtkTimerLog::TimerLog[i-1].CpuTicks,
                vtkTimerLog::TimerLog[i].Event);
      }
    vtkTimerLog::DumpEntry(os_with_warning_C4701, vtkTimerLog::MaxEntries-vtkTimerLog::NextEntry,
                    vtkTimerLog::TimerLog[0].WallTime,
                    vtkTimerLog::TimerLog[0].WallTime
                    -vtkTimerLog::TimerLog[vtkTimerLog::MaxEntries-1].WallTime,
                    vtkTimerLog::TimerLog[0].CpuTicks,
                    vtkTimerLog::TimerLog[0].CpuTicks
                    -vtkTimerLog::TimerLog[vtkTimerLog::MaxEntries-1].CpuTicks,
                    vtkTimerLog::TimerLog[0].Event);
    for (i=1; i<vtkTimerLog::NextEntry; i++)
      {
      vtkTimerLog::DumpEntry(os_with_warning_C4701, vtkTimerLog::MaxEntries-vtkTimerLog::NextEntry+i,
                      vtkTimerLog::TimerLog[i].WallTime,
                      vtkTimerLog::TimerLog[i].WallTime
                      - vtkTimerLog::TimerLog[i-1].WallTime,
                      vtkTimerLog::TimerLog[i].CpuTicks,
                      vtkTimerLog::TimerLog[i].CpuTicks
                      - vtkTimerLog::TimerLog[i-1].CpuTicks,
                      vtkTimerLog::TimerLog[i].Event);
      }
    }
  else
    {
    vtkTimerLog::DumpEntry(os_with_warning_C4701, 0, vtkTimerLog::TimerLog[0].WallTime, 0,
                    vtkTimerLog::TimerLog[0].CpuTicks, 0,
                    vtkTimerLog::TimerLog[0].Event);
    for (i=1; i<vtkTimerLog::NextEntry; i++)
      {
      vtkTimerLog::DumpEntry(os_with_warning_C4701, i, vtkTimerLog::TimerLog[i].WallTime,
                      vtkTimerLog::TimerLog[i].WallTime
                      - vtkTimerLog::TimerLog[i-1].WallTime,
                      vtkTimerLog::TimerLog[i].CpuTicks,
                      vtkTimerLog::TimerLog[i].CpuTicks
                      - vtkTimerLog::TimerLog[i-1].CpuTicks,
                      vtkTimerLog::TimerLog[i].Event);
      }
    }

  os_with_warning_C4701.close();
#endif
}


//----------------------------------------------------------------------------
// Print method for vtkTimerLog.
void vtkTimerLog::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);

  int i;

  os << indent << "MaxEntries: " << vtkTimerLog::MaxEntries << "\n";
  os << indent << "NextEntry: " << vtkTimerLog::NextEntry << "\n";
  os << indent << "WrapFlag: " << vtkTimerLog::WrapFlag << "\n";
  os << indent << "TicksPerSecond: " << vtkTimerLog::TicksPerSecond << "\n";
  os << "\n";

  os << indent << "Entry \tWall Time\tCpuTicks\tEvent\n";
  os << indent << "----------------------------------------------\n";

  if ( vtkTimerLog::WrapFlag )
    {
    for (i=vtkTimerLog::NextEntry; i<vtkTimerLog::MaxEntries; i++)
      {
      os << indent << i << "\t\t" << TimerLog[i].WallTime << "\t\t" <<
        TimerLog[i].CpuTicks << "\t\t" << TimerLog[i].Event << "\n";
      }
    }

  for (i=0; i<vtkTimerLog::NextEntry; i++)
    {
    os << indent << i << "\t\t" << TimerLog[i].WallTime << "\t\t" <<
      TimerLog[i].CpuTicks << "\t\t" << TimerLog[i].Event << "\n";
    }

  os << "\n" << indent << "StartTime: " << this->StartTime << "\n";
  os << indent << "WrapFlag: " << vtkTimerLog::WrapFlag << "\n";
}


// Methods to support simple timer functionality, separate from
// timer table logging.

//----------------------------------------------------------------------------
// Returns the elapsed number of seconds since January 1, 1970. This
// is also called Universal Coordinated Time.
double vtkTimerLog::GetUniversalTime()
{
  double currentTimeInSeconds;

#ifdef _WIN32
#ifdef _WIN32_WCE
  FILETIME CurrentTime;
  SYSTEMTIME st;
  GetLocalTime(&st);
  SystemTimeToFileTime(&st, &CurrentTime);
  currentTimeInSeconds = CurrentTime.dwHighDateTime;
  currentTimeInSeconds *= 429.4967296;
  currentTimeInSeconds = currentTimeInSeconds +
        CurrentTime.dwLowDateTime / 10000000.0;
#else
  timeb CurrentTime;
  static double scale = 1.0/1000.0;
  ::ftime( &CurrentTime );
  currentTimeInSeconds = CurrentTime.time + scale * CurrentTime.millitm;
#endif
#else
  timeval CurrentTime;
  static double scale = 1.0/1000000.0;
  gettimeofday( &CurrentTime, NULL );
  currentTimeInSeconds = CurrentTime.tv_sec + scale * CurrentTime.tv_usec;
#endif

  return currentTimeInSeconds;
}

//----------------------------------------------------------------------------
double vtkTimerLog::GetCPUTime()
{
  double   currentCPUTime = 1.0;
#ifndef _WIN32_WCE
  currentCPUTime = static_cast<double>(clock()) /static_cast<double>(CLOCKS_PER_SEC);
#endif
  return currentCPUTime;
}

//----------------------------------------------------------------------------
// Set the StartTime to the current time. Used with GetElapsedTime().
void vtkTimerLog::StartTimer()
{
  this->StartTime = vtkTimerLog::GetUniversalTime();
}

//----------------------------------------------------------------------------
// Sets EndTime to the current time. Used with GetElapsedTime().
void vtkTimerLog::StopTimer()
{
  this->EndTime = vtkTimerLog::GetUniversalTime();
}

//----------------------------------------------------------------------------
// Returns the difference between StartTime and EndTime as
// a floating point value indicating the elapsed time in seconds.
double vtkTimerLog::GetElapsedTime()
{
  return (this->EndTime - this->StartTime);
}

//----------------------------------------------------------------------------
void vtkTimerLog::DumpEntry(ostream& os, int index, double ttime,
                            double deltatime,
                            int tick, int deltatick, const char *event)
{
  os << index << "   "
     << ttime << "  "
     << deltatime << "   "
     << static_cast<double>(tick)/vtkTimerLog::TicksPerSecond << "  "
     << static_cast<double>(deltatick)/vtkTimerLog::TicksPerSecond << "  ";
  if (deltatime == 0.0)
    {
    os << "0.0   ";
    }
  else
    {
    os << 100.0*deltatick/vtkTimerLog::TicksPerSecond/deltatime << "   ";
    }
  os << event << "\n";
}

//----------------------------------------------------------------------------
void vtkTimerLog::SetMaxEntries(int a)
{
  int num, i, offset;
  vtkTimerLogEntry *newLog, *tmp;

  if (vtkTimerLog::MaxEntries == a)
    {
    return;
    }

  newLog = new vtkTimerLogEntry[a];
  if (vtkTimerLog::TimerLog == NULL)
    {
    vtkTimerLog::MaxEntries = a;
    vtkTimerLog::TimerLog = newLog;
    return;
    }

  // Copy the old log to the new.
  num = vtkTimerLog::GetNumberOfEvents();
  offset = 0;
  if (a < num)
    {
    offset = num - a;
    num = a;
    }

  for (i = 0; i < num; ++i)
    {
    tmp = vtkTimerLog::GetEvent(i+offset);
    newLog[i] = *tmp;
    }

  delete [] vtkTimerLog::TimerLog;
  vtkTimerLog::MaxEntries = a;
  vtkTimerLog::TimerLog = newLog;
  vtkTimerLog::WrapFlag = 0;
  vtkTimerLog::NextEntry = num;
}


//----------------------------------------------------------------------------
int vtkTimerLog::GetMaxEntries()
{
  return vtkTimerLog::MaxEntries;
}