/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2007 INRIA
 *
 * 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>
 */
#include "hierarchical-mobility-model.h"
#include "mobility-model-notifier.h"

namespace ns3 {

NS_OBJECT_ENSURE_REGISTERED (HierarchicalMobilityModel);

TypeId 
HierarchicalMobilityModel::GetTypeId (void)
{
  static TypeId tid = TypeId ("HierarchicalMobilityModel")
    .SetParent<MobilityModel> ();
  return tid;
}

HierarchicalMobilityModel::HierarchicalMobilityModel (Ptr<MobilityModel> child, Ptr<MobilityModel> parent)
  : m_child (child),
    m_parent (parent)
{
  Ptr<MobilityModelNotifier> childNotifier = 
    m_child->GetObject<MobilityModelNotifier> ();
  Ptr<MobilityModelNotifier> parentNotifier = 
    m_parent->GetObject<MobilityModelNotifier> ();
  if (childNotifier == 0)
    {
      childNotifier = CreateObject<MobilityModelNotifier> ();
      child->AggregateObject (childNotifier);
    }
  if (parentNotifier == 0)
    {
      parentNotifier = CreateObject<MobilityModelNotifier> ();
      parent->AggregateObject (parentNotifier);
    }
  childNotifier->TraceConnect ("/course-changed", MakeCallback (&HierarchicalMobilityModel::ChildChanged, this));
  parentNotifier->TraceConnect ("/course-changed", MakeCallback (&HierarchicalMobilityModel::ParentChanged, this));
}

Ptr<MobilityModel> 
HierarchicalMobilityModel::GetChild (void) const
{
  return m_child;
}

Ptr<MobilityModel> 
HierarchicalMobilityModel::GetParent (void) const
{
  return m_parent;
}

Vector
HierarchicalMobilityModel::DoGetPosition (void) const
{
  Vector parentPosition = m_parent->GetPosition ();
  Vector childPosition = m_child->GetPosition ();
  return Vector (parentPosition.x + childPosition.x,
		   parentPosition.y + childPosition.y,
		   parentPosition.z + childPosition.z);
}
void 
HierarchicalMobilityModel::DoSetPosition (const Vector &position)
{
  // This implementation of DoSetPosition is really an arbitraty choice.
  // anything else would have been ok.
  Vector parentPosition = m_parent->GetPosition ();
  Vector childPosition (position.x - parentPosition.x,
			  position.y - parentPosition.y,
			  position.z - parentPosition.z);
  m_child->SetPosition (childPosition);
}
Vector
HierarchicalMobilityModel::DoGetVelocity (void) const
{
  Vector parentSpeed = m_parent->GetVelocity ();
  Vector childSpeed = m_child->GetVelocity ();
  Vector speed (parentSpeed.x + childSpeed.x,
               parentSpeed.y + childSpeed.y,
               parentSpeed.z + childSpeed.z);
  return speed;
}

void 
HierarchicalMobilityModel::ParentChanged (const TraceContext &context, Ptr<const MobilityModel> model)
{
  MobilityModel::NotifyCourseChange ();
}

void 
HierarchicalMobilityModel::ChildChanged (const TraceContext &context, Ptr<const MobilityModel> model)
{
  MobilityModel::NotifyCourseChange ();
}



} // namespace ns3