/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2005,2006 INRIA

 * Copyright (c) 2007 Emmanuelle Laprise

 *

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

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * This program 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

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 * TimeStep support by Emmanuelle Laprise <emmanuelle.laprise@bluekazoo.ca>

 */

#include "nstime.h"

#include "abort.h"

#include "global-value.h"

#include "enum.h"

#include "string.h"

#include "object.h"

#include "config.h"

#include "log.h"

#include <cmath>

#include <iomanip>  // showpos

#include <sstream>

NS_LOG_COMPONENT_DEFINE ("Time");

namespace ns3 {

// The set of marked times

// static

Time::MarkedTimes * Time::g_markingTimes = 0;

// Function called to force static initialization

// static

bool Time::StaticInit ()

{

  static bool firstTime = true;

  if (firstTime)

    {

      if (! g_markingTimes)

	{

	  g_markingTimes = new Time::MarkedTimes;

	}

      // Schedule the cleanup.

      // We'd really like:

      //   NS_LOG_LOGIC ("scheduling ClearMarkedTimes()");

      //   Simulator::Schedule ( Seconds (0), & ClearMarkedTimes);

      //   [or even better:  Simulator::AtStart ( & ClearMarkedTimes ); ]

      // But this triggers a static initialization order error,

      // since the Simulator static initialization may not have occurred.

      // Instead, we call ClearMarkedTimes directly from Simulator::Run ()

      firstTime = false;

    }

  return firstTime;

}

Time::Time (const std::string& s)

{

  NS_LOG_FUNCTION (this << &s);

  std::string::size_type n = s.find_first_not_of ("+-0123456789.");

  if (n != std::string::npos)

    { // Found non-numeric

      std::istringstream iss;

      iss.str (s.substr (0, n));

      double r;

      iss >> r;

      std::string trailer = s.substr (n, std::string::npos);

      if (trailer == std::string ("s"))

        {

          *this = Time::FromDouble (r, Time::S);

        }

      else if (trailer == std::string ("ms"))

        {

          *this = Time::FromDouble (r, Time::MS);

        }

      else if (trailer == std::string ("us"))

        {

          *this = Time::FromDouble (r, Time::US);

        }

      else if (trailer == std::string ("ns"))

        {

          *this = Time::FromDouble (r, Time::NS);

        }

      else if (trailer == std::string ("ps"))

        {

          *this = Time::FromDouble (r, Time::PS);

        }

      else if (trailer == std::string ("fs"))

        {

          *this = Time::FromDouble (r, Time::FS);

        }

      else

        {

          NS_ABORT_MSG ("Can't Parse Time " << s);

        }

    }

  else

    {

      // they didn't provide units, assume seconds

      std::istringstream iss;

      iss.str (s);

      double v;

      iss >> v;

      *this = Time::FromDouble (v, Time::S);

    }

  if (g_markingTimes)

    {

      Mark (this);

    }

}

// static

struct Time::Resolution

Time::SetDefaultNsResolution (void)

{

  NS_LOG_FUNCTION_NOARGS ();

  struct Resolution resolution;

  SetResolution (Time::NS, &resolution, false);

  return resolution;

}

// static

void

Time::SetResolution (enum Unit resolution)

{

  NS_LOG_FUNCTION (resolution);

  SetResolution (resolution, PeekResolution ());

}

// static

void

Time::SetResolution (enum Unit unit, struct Resolution *resolution,

                     const bool convert /* = true */)

{

  NS_LOG_FUNCTION (resolution);

  if (convert)

    { // We have to convert old values

      ConvertTimes (unit);

    }

  int8_t power [LAST] = { 15, 12, 9, 6, 3, 0};

  for (int i = 0; i < Time::LAST; i++)

    {

      int shift = power[i] - power[(int)unit];

      int64_t factor = (int64_t) std::pow (10, std::fabs (shift));

      struct Information *info = &resolution->info[i];

      info->factor = factor;

      if (shift == 0)

        {

          info->timeFrom = int64x64_t (1);

          info->timeTo = int64x64_t (1);

          info->toMul = true;

          info->fromMul = true;

        }

      else if (shift > 0)

        {

          info->timeFrom = int64x64_t (factor);

          info->timeTo = int64x64_t::Invert (factor);

          info->toMul = false;

          info->fromMul = true;

        }

      else

        {

          NS_ASSERT (shift < 0);

          info->timeFrom = int64x64_t::Invert (factor);

          info->timeTo = int64x64_t (factor);

          info->toMul = true;

          info->fromMul = false;

        }

    }

  resolution->unit = unit;

}

// static

void

Time::ClearMarkedTimes ()

{

  NS_LOG_FUNCTION_NOARGS ();

  if (g_markingTimes)

    {

      NS_LOG_LOGIC ("clearing MarkedTimes");

      delete g_markingTimes;

      g_markingTimes = 0;

    }

}  // Time::ClearMarkedTimes

// static

void

Time::Mark (Time * const time)

{

  NS_LOG_FUNCTION (time);

  NS_ASSERT (time != 0);

  if (g_markingTimes)

    {

      std::pair< MarkedTimes::iterator, bool> ret;

      ret = g_markingTimes->insert ( time);

      NS_LOG_LOGIC ("\t[" << g_markingTimes->size () << "] recording " << time);

      if (ret.second == false)

        {

          NS_LOG_WARN ("already recorded " << time << "!");

        }

   }

}  // Time::Mark ()

// static

void

Time::Clear (Time * const time)

{

  NS_LOG_FUNCTION (time);

  NS_ASSERT (time != 0);

  if (g_markingTimes)

    {

      NS_ASSERT_MSG (g_markingTimes->count (time) == 1,

		     "Time object " << time <<

		     " registered " << g_markingTimes->count (time) <<

		     " times (should be 1)." );

      MarkedTimes::size_type num = g_markingTimes->erase (time);

      if (num != 1)

	{

	  NS_LOG_WARN ("unexpected result erasing " << time << "!");

	  NS_LOG_WARN ("got " << num << ", expected 1");

	}

      else

	{

	  NS_LOG_LOGIC ("\t[" << g_markingTimes->size () << "] removing  " << time);

	}

    }

}  // Time::Clear ()

// static

void

Time::ConvertTimes (const enum Unit unit)

{

  NS_LOG_FUNCTION_NOARGS();

  NS_ASSERT_MSG (g_markingTimes != 0,

		 "No MarkedTimes registry. "

		 "Time::SetResolution () called more than once?");

  for ( MarkedTimes::iterator it = g_markingTimes->begin();

	it != g_markingTimes->end();

	it++ )

    {

      Time * const tp = *it;

      if ( ! (    (tp->m_data == std::numeric_limits<int64_t>::min ())

               || (tp->m_data == std::numeric_limits<int64_t>::max ())

             )

         )

        {

      tp->m_data = tp->ToInteger (unit);

    }

    }

  NS_LOG_LOGIC ("logged " << g_markingTimes->size () << " Time objects.");

  ClearMarkedTimes ();

}  // Time::ConvertTimes ()

// static

enum Time::Unit

Time::GetResolution (void)

{

  // No function log b/c it interferes with operator<<

  return PeekResolution ()->unit;

}

std::ostream&

operator<< (std::ostream& os, const Time & time)

{

  std::string unit;

  Time::Unit res = Time::GetResolution ();

  switch (res)

    {

    case Time::S:

      unit = "s";

      break;

    case Time::MS:

      unit = "ms";

      break;

    case Time::US:

      unit = "us";

      break;

    case Time::NS:

      unit = "ns";

      break;

    case Time::PS:

      unit = "ps";

      break;

    case Time::FS:

      unit = "fs";

      break;

    case Time::LAST:

      NS_ABORT_MSG ("can't be reached");

      unit = "unreachable";

      break;

    }

  int64_t v = time.ToInteger (res);

  std::ios_base::fmtflags ff = os.flags ();

  os.flags (ff);  // Restore stream flags

  return os;

}

std::istream& operator>> (std::istream& is, Time & time)

{

  std::string value;

  is >> value;

  time = Time (value);

  return is;

}

ATTRIBUTE_VALUE_IMPLEMENT (Time);

Ptr<const AttributeChecker>

MakeTimeChecker (const Time min, const Time max)

{

  NS_LOG_FUNCTION (min << max);

  struct Checker : public AttributeChecker

  {

    Checker (const Time minValue, const Time maxValue)

      : m_minValue (minValue),

        m_maxValue (maxValue) {}

    virtual bool Check (const AttributeValue &value) const {

      NS_LOG_FUNCTION (&value);

      const TimeValue *v = dynamic_cast<const TimeValue *> (&value);

      if (v == 0)

        {

          return false;

        }

      return v->Get () >= m_minValue && v->Get () <= m_maxValue;

    }

    virtual std::string GetValueTypeName (void) const {

      NS_LOG_FUNCTION_NOARGS ();

      return "ns3::TimeValue";

    }

    virtual bool HasUnderlyingTypeInformation (void) const {

      NS_LOG_FUNCTION_NOARGS ();

      return true;

    }

    virtual std::string GetUnderlyingTypeInformation (void) const {

      NS_LOG_FUNCTION_NOARGS ();

      std::ostringstream oss;

      oss << "Time" << " " << m_minValue << ":" << m_maxValue;

      return oss.str ();

    }

    virtual Ptr<AttributeValue> Create (void) const {

      NS_LOG_FUNCTION_NOARGS ();

      return ns3::Create<TimeValue> ();

    }

    virtual bool Copy (const AttributeValue &source, AttributeValue &destination) const {

      NS_LOG_FUNCTION (&source << &destination);

      const TimeValue *src = dynamic_cast<const TimeValue *> (&source);

      TimeValue *dst = dynamic_cast<TimeValue *> (&destination);

      if (src == 0 || dst == 0)

        {

          return false;

        }

      *dst = *src;

      return true;

    }

    Time m_minValue;

    Time m_maxValue;

  } *checker = new Checker (min, max);

  return Ptr<const AttributeChecker> (checker, false);

}

} // namespace ns3