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

/*

 * Copyright (c) 2007 INRIA, Gustavo Carneiro

 *

 * 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

 *

 * Authors: Gustavo Carneiro <gjcarneiro@gmail.com>,

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

 */

#include "object.h"

#include "assert.h"

#include "singleton.h"

#include "attribute.h"

#include "log.h"

#include "string.h"

#include <vector>

#include <sstream>

NS_LOG_COMPONENT_DEFINE ("Object");

namespace ns3 {

/*********************************************************************

 *         The Object implementation

 *********************************************************************/

NS_OBJECT_ENSURE_REGISTERED (Object);

Object::AggregateIterator::AggregateIterator ()

  : m_first (0),

    m_current (0)

{}

bool 

Object::AggregateIterator::HasNext (void) const

{

  if (m_current != 0 && m_current->m_next != PeekPointer (m_first))

    {

      return true;

    }

  return false;

}

Ptr<const Object> 

Object::AggregateIterator::Next (void)

{

  m_current = m_current->m_next;

  return m_current;

}

Object::AggregateIterator::AggregateIterator (Ptr<const Object> first)

  : m_first (first),

    m_current (first)

{}

TypeId 

Object::GetInstanceTypeId (void) const

{

  return m_tid;

}

TypeId 

Object::GetTypeId (void)

{

  static TypeId tid = TypeId ("ns3::Object")

    .SetParent<ObjectBase> ()

    ;

  return tid;

}

Object::Object ()

  : m_count (1),

    m_tid (Object::GetTypeId ()),

    m_disposed (false),

    m_next (this)

{}

Object::~Object () 

{

  m_next = 0;

}

Object::Object (const Object &o)

  : m_count (1),

    m_tid (o.m_tid),

    m_disposed (false),

    m_next (this)

{}

uint32_t

Object::GetReferenceCount (void) const

{

  return m_count;

}

void

Object::Construct (const AttributeList &attributes)

{

  ConstructSelf (attributes);

}

Ptr<Object>

Object::DoGetObject (TypeId tid) const

{

  NS_ASSERT (CheckLoose ());

  const Object *currentObject = this;

  TypeId objectTid = Object::GetTypeId ();

  do {

    NS_ASSERT (currentObject != 0);

    TypeId cur = currentObject->GetInstanceTypeId ();

    while (cur != tid && cur != objectTid)

      {

        cur = cur.GetParent ();

      }

    if (cur == tid)

      {

        return const_cast<Object *> (currentObject);

      }

    currentObject = currentObject->m_next;

  } while (currentObject != this);

  return 0;

}

void 

Object::Dispose (void)

{

  Object *current = this;

  do {

    NS_ASSERT (current != 0);

    NS_ASSERT (!current->m_disposed);

    current->DoDispose ();

    current->m_disposed = true;

    current = current->m_next;

  } while (current != this);

}

void 

Object::AggregateObject (Ptr<Object> o)

{

  NS_ASSERT (!m_disposed);

  NS_ASSERT (!o->m_disposed);

  NS_ASSERT (CheckLoose ());

  NS_ASSERT (o->CheckLoose ());

  if (DoGetObject (o->GetInstanceTypeId ()))

    {

      NS_FATAL_ERROR ("Object::AggregateObject(): "

                      "Multiple aggregation of objects of type " << 

                      o->GetInstanceTypeId ().GetName ());

    }

  Object *other = PeekPointer (o);

  Object *next = m_next;

  m_next = other->m_next;

  other->m_next = next;

  NS_ASSERT (CheckLoose ());

  NS_ASSERT (o->CheckLoose ());

}

Object::AggregateIterator 

Object::GetAggregateIterator (void) const

{

  return AggregateIterator (this);

}

void 

Object::SetTypeId (TypeId tid)

{

  NS_ASSERT (Check ());

  m_tid = tid;

}

void

Object::DoDispose (void)

{

  NS_ASSERT (!m_disposed);

}

bool 

Object::Check (void) const

{

  return (m_count > 0);

}

/* In some cases, when an event is scheduled against a subclass of

 * Object, and if no one owns a reference directly to this object, the

 * object is alive, has a refcount of zero and the method ran when the

 * event expires runs against the raw pointer which means that we are

 * manipulating an object with a refcount of zero.  So, instead we

 * check the aggregate reference count.

 */

bool 

Object::CheckLoose (void) const

{

  uint32_t refcount = 0;

  const Object *current = this;

  do

    {

      refcount += current->m_count;

      current = current->m_next;

    }

  while (current != this);

  return (refcount > 0);

}

void

Object::MaybeDelete (void) const

{

  // First, check if any of the attached

  // Object has a non-zero count.

  const Object *current = this;

  do {

    NS_ASSERT (current != 0);

    if (current->m_count != 0)

      {

        return;

      }

    current = current->m_next;

  } while (current != this);

  // Ensure we are disposed.

  Object *tmp = const_cast<Object *> (this);

  const Object *end = this;

  do {

    NS_ASSERT (current != 0);

    Object *next = tmp->m_next;

    if (!tmp->m_disposed)

      {

        tmp->DoDispose ();

      }

    tmp = next;

  } while (tmp != end);

  // all attached objects have a zero count so, 

  // we can delete all attached objects.

  current = this;

  do {

    NS_ASSERT (current != 0);

    Object *next = current->m_next;

    delete current;

    current = next;

  } while (current != end);

}

} // namespace ns3

#ifdef RUN_SELF_TESTS

#include "test.h"

#include "object-factory.h"

namespace {

class BaseA : public ns3::Object

{

public:

  static ns3::TypeId GetTypeId (void) {

    static ns3::TypeId tid = ns3::TypeId ("BaseA")

      .SetParent (Object::GetTypeId ())

      .HideFromDocumentation ()

      .AddConstructor<BaseA> ();

    return tid;

  }

  BaseA ()

  {}

  virtual void Dispose (void) {}

};

class DerivedA : public BaseA

{

public:

  static ns3::TypeId GetTypeId (void) {

    static ns3::TypeId tid = ns3::TypeId ("DerivedA")

      .SetParent (BaseA::GetTypeId ())

      .HideFromDocumentation ()

      .AddConstructor<DerivedA> ();

    return tid;

  }

  DerivedA ()

  {}

  virtual void Dispose (void) {

    BaseA::Dispose ();

  }

};

class BaseB : public ns3::Object

{

public:

  static ns3::TypeId GetTypeId (void) {

    static ns3::TypeId tid = ns3::TypeId ("BaseB")

      .SetParent (Object::GetTypeId ())

      .HideFromDocumentation ()

      .AddConstructor<BaseB> ();

    return tid;

  }

  BaseB ()

  {}

  virtual void Dispose (void) {}

};

class DerivedB : public BaseB

{

public:

  static ns3::TypeId GetTypeId (void) {

    static ns3::TypeId tid = ns3::TypeId ("DerivedB")

      .SetParent (BaseB::GetTypeId ())

      .HideFromDocumentation ()

      .AddConstructor<DerivedB> ();

    return tid;

  }

  DerivedB ()

  {}

  virtual void Dispose (void) {

    BaseB::Dispose ();

  }

};

NS_OBJECT_ENSURE_REGISTERED (BaseA);

NS_OBJECT_ENSURE_REGISTERED (DerivedA);

NS_OBJECT_ENSURE_REGISTERED (BaseB);

NS_OBJECT_ENSURE_REGISTERED (DerivedB);

} // namespace anonymous

namespace ns3 {

class ObjectTest : public Test

{

public:

  ObjectTest ();

  virtual bool RunTests (void);

};

ObjectTest::ObjectTest ()

  : Test ("Object")

{}

bool 

ObjectTest::RunTests (void)

{

  bool result = true;

  Ptr<BaseA> baseA = CreateObject<BaseA> ();

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<BaseA> (), baseA);

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<BaseA> (DerivedA::GetTypeId ()), 0);

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<DerivedA> (), 0);

  baseA = CreateObject<DerivedA> ();

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<BaseA> (), baseA);

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<BaseA> (DerivedA::GetTypeId ()), baseA);

  NS_TEST_ASSERT_UNEQUAL (baseA->GetObject<DerivedA> (), 0);

  baseA = CreateObject<BaseA> ();

  Ptr<BaseB> baseB = CreateObject<BaseB> ();

  Ptr<BaseB> baseBCopy = baseB;

  baseA->AggregateObject (baseB);

  NS_TEST_ASSERT_UNEQUAL (baseA->GetObject<BaseA> (), 0);

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<DerivedA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseA->GetObject<BaseB> (), 0);

  NS_TEST_ASSERT_EQUAL (baseA->GetObject<DerivedB> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<BaseB> (), 0);

  NS_TEST_ASSERT_EQUAL (baseB->GetObject<DerivedB> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<BaseA> (), 0);

  NS_TEST_ASSERT_EQUAL (baseB->GetObject<DerivedA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseBCopy->GetObject<BaseA> (), 0);

  baseA = CreateObject<DerivedA> ();

  baseB = CreateObject<DerivedB> ();

  baseBCopy = baseB;

  baseA->AggregateObject (baseB);

  NS_TEST_ASSERT_UNEQUAL (baseA->GetObject<DerivedB> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseA->GetObject<BaseB> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<DerivedA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<BaseA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseBCopy->GetObject<DerivedA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseBCopy->GetObject<BaseA> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<DerivedB> (), 0);

  NS_TEST_ASSERT_UNEQUAL (baseB->GetObject<BaseB> (), 0);

  baseA = CreateObject<BaseA> ();

  baseB = CreateObject<BaseB> ();

  baseA->AggregateObject (baseB);

  baseA = 0;

  baseA = baseB->GetObject<BaseA> ();

  // Test the object creation code of TypeId

  ObjectFactory factory;

  factory.SetTypeId (BaseA::GetTypeId ());

  Ptr<Object> a = factory.Create ();

  NS_TEST_ASSERT_EQUAL (a->GetObject<BaseA> (), a);

  NS_TEST_ASSERT_EQUAL (a->GetObject<BaseA> (DerivedA::GetTypeId ()), 0);

  NS_TEST_ASSERT_EQUAL (a->GetObject<DerivedA> (), 0);

  factory.SetTypeId (DerivedA::GetTypeId ());

  a = factory.Create ();

  NS_TEST_ASSERT_EQUAL (a->GetObject<BaseA> (), a);

  NS_TEST_ASSERT_EQUAL (a->GetObject<BaseA> (DerivedA::GetTypeId ()), a);

  NS_TEST_ASSERT_UNEQUAL (a->GetObject<DerivedA> (), 0);

  return result;

}

static ObjectTest g_interfaceObjectTests;

} // namespace ns3

#endif /* RUN_SELF_TESTS */