/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2009 IITP RAS
 *
 * 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: Denis Fakhriev <fakhriev@iitp.ru>
 */
#include <cmath>
#include "ns3/simulator.h"
#include "ns3/boolean.h"
#include "ns3/double.h"
#include "ns3/test.h"
#include "ns3/config.h"
#include "ns3/steady-state-random-waypoint-mobility-model.h"
#include "ns3/rng-seed-manager.h"

namespace ns3 {

class SteadyStateRandomWaypointTest : public TestCase
{
public:
  SteadyStateRandomWaypointTest ()
    : TestCase ("Check steady-state rwp mobility model velocity and position distributions") {}
  virtual ~SteadyStateRandomWaypointTest () {}

private:
  std::vector<Ptr<MobilityModel> > mobilityStack;
  double count;
private:
  virtual void DoRun (void);
  virtual void DoTeardown (void);
  void DistribCompare ();
};

void
SteadyStateRandomWaypointTest::DoTeardown (void)
{
  mobilityStack.clear();
}

void
SteadyStateRandomWaypointTest::DoRun (void)
{
  SeedManager::SetSeed (123);

  // Total simulation time, seconds
  double totalTime = 1000;

  ObjectFactory mobilityFactory;
  mobilityFactory.SetTypeId ("ns3::SteadyStateRandomWaypointMobilityModel");
  mobilityFactory.Set ("MinSpeed", DoubleValue (0.01));
  mobilityFactory.Set ("MaxSpeed", DoubleValue (20.0));
  mobilityFactory.Set ("MinPause", DoubleValue (0.0));
  mobilityFactory.Set ("MaxPause", DoubleValue (0.0));
  mobilityFactory.Set ("MinX", DoubleValue (0));
  mobilityFactory.Set ("MaxX", DoubleValue (1000));
  mobilityFactory.Set ("MinY", DoubleValue (0));
  mobilityFactory.Set ("MaxY", DoubleValue (600));

  // Populate the vector of mobility models.
  count = 10000;
  for (uint32_t i = 0; i < count; i++)
    {
      // Create a new mobility model.
      Ptr<MobilityModel> model = mobilityFactory.Create ()->GetObject<MobilityModel> ();

      // Add this mobility model to the stack.
      mobilityStack.push_back (model);
      Simulator::Schedule (Seconds (0.0), &Object::Initialize, model);
    } 

  Simulator::Schedule (Seconds (0.001), &SteadyStateRandomWaypointTest::DistribCompare, this);
  Simulator::Schedule (Seconds (totalTime), &SteadyStateRandomWaypointTest::DistribCompare, this);
  Simulator::Stop (Seconds (totalTime));
  Simulator::Run ();
  Simulator::Destroy ();
}

void
SteadyStateRandomWaypointTest::DistribCompare ()
{
  double velocity;
  double sum_x = 0;
  double sum_y = 0;
  double sum_v = 0;
  std::vector<Ptr<MobilityModel> >::iterator i;
  Ptr<MobilityModel> model;
  for (i = mobilityStack.begin (); i != mobilityStack.end (); ++i)
    {
      model = (*i);
      velocity = std::sqrt (std::pow (model->GetVelocity ().x, 2) + std::pow (model->GetVelocity ().y, 2));
      sum_x += model->GetPosition ().x;
      sum_y += model->GetPosition ().y;
      sum_v += velocity;
    }
  double mean_x = sum_x / count;
  double mean_y = sum_y / count;
  double mean_v = sum_v / count;

  NS_TEST_EXPECT_MSG_EQ_TOL (mean_x, 500, 25.0, "Got unexpected x-position mean value");
  NS_TEST_EXPECT_MSG_EQ_TOL (mean_y, 300, 15.0, "Got unexpected y-position mean value");
  NS_TEST_EXPECT_MSG_EQ_TOL (mean_v, 2.6, 0.13, "Got unexpected velocity mean value");

  sum_x = 0;
  sum_y = 0;
  sum_v = 0;
  double tmp;
  for (i = mobilityStack.begin (); i != mobilityStack.end (); ++i)
    {
      model = (*i);
      velocity = std::sqrt (std::pow (model->GetVelocity ().x, 2) + std::pow (model->GetVelocity ().y, 2));
      tmp = model->GetPosition ().x - mean_x;
      sum_x += tmp * tmp;
      tmp = model->GetPosition ().y - mean_y;
      sum_y += tmp * tmp;
      tmp = velocity - mean_v;
      sum_v += tmp * tmp;
    }
  double dev_x = std::sqrt (sum_x / (count - 1));
  double dev_y = std::sqrt (sum_y / (count - 1));
  double dev_v = std::sqrt (sum_v / (count - 1));

  NS_TEST_EXPECT_MSG_EQ_TOL (dev_x, 230, 10.0, "Got unexpected x-position standard deviation");
  NS_TEST_EXPECT_MSG_EQ_TOL (dev_y, 140, 7.0, "Got unexpected y-position standard deviation");
  NS_TEST_EXPECT_MSG_EQ_TOL (dev_v, 4.4, 0.22, "Got unexpected velocity standard deviation");
}

struct SteadyStateRandomWaypointTestSuite : public TestSuite
{
  SteadyStateRandomWaypointTestSuite () : TestSuite ("steady-state-rwp-mobility-model", UNIT)
  {
    AddTestCase (new SteadyStateRandomWaypointTest, TestCase::QUICK);
  }
} g_steadyStateRandomWaypointTestSuite;

} // namespace ns3
