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

/*

 * Copyright (c) 2006 Georgia Tech Research Corporation

 *

 * 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: George F. Riley<riley@ece.gatech.edu>

 */

// Implementation for ns3 Application base class.

// George F. Riley, Georgia Tech, Fall 2006

#include "application.h"

#include "ns3/node.h"

#include "ns3/nstime.h"

#include "ns3/random-variable.h"

#include "ns3/simulator.h"

using namespace std;

namespace ns3 {

// Application Methods

// \brief Application Constructor

Application::Application(Ptr<Node> n) 

    : m_node (n),

      m_startVar(0), m_stopVar(0),

      m_start(false), m_stop(false)

{

  m_node->AddApplication (this);

}

// \brief Application Destructor

Application::~Application()

{}

void

Application::DoDispose (void)

{

  m_node = 0;

  if (m_start) 

    {

      Simulator::Cancel(m_startEvent);

      m_start = false;

    }

  if (m_stop) 

    {

      Simulator::Cancel(m_stopEvent);

      m_stop = false;

    }

  delete m_startVar;

  m_startVar = 0;

  delete m_stopVar;

  m_stopVar = 0;

// \brief Specify application start time

// The virtual method STartApp will be called at the time

// specified by startTime.

// \param Time to start application (absolute time, from start of simulation)

void Application::Start(const Time& startTime)

{

  delete m_startVar;

  m_startVar = new ConstantVariable(startTime.GetSeconds());

  ScheduleStart();

}

void Application::Start(const RandomVariable& startVar)

{ // Start at random time

  delete m_startVar;

  m_startVar = startVar.Copy();

  ScheduleStart();

}

// \brief Specify application stop time

// The virtual method StopApp will be called at the time

// specified by stopTime.

// \param Time to stop application (absolute time, from start of simulation)

void Application::Stop(const Time& stopTime)

{

  delete m_stopVar;

  m_stopVar = new ConstantVariable(stopTime.GetSeconds());

  ScheduleStop();

}

void Application::Stop(const RandomVariable& stopVar)

{ // Stop at random time

  delete m_stopVar;

  m_stopVar = stopVar.Copy();

  ScheduleStop();

}

Ptr<Node> Application::GetNode() const

{

  return m_node;

}

// Protected methods

// StartApp and StopApp will likely be overridden by application subclasses

void Application::StartApplication()

{ // Provide null functionality in case subclass is not interested

}

void Application::StopApplication()

{ // Provide null functionality in case subclass is not interested

}

// Private helpers

void Application::ScheduleStart()

{

  m_startEvent = Simulator::Schedule(Seconds(m_startVar->GetValue()) -

                                     Simulator::Now(),

                                     &Application::StartApplication, this);

  m_start = true;

}

void Application::ScheduleStop()

{

  m_stopEvent = Simulator::Schedule(Seconds(m_stopVar->GetValue()) -

                                     Simulator::Now(),

                                     &Application::StopApplication, this);

  m_stop = true;

}

} //namespace ns3