/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library 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
* OpenSceneGraph Public License for more details.
*/

#include <osg/Node>
#include <osg/Group>
#include <osg/NodeVisitor>
#include <osg/Notify>
#include <osg/OccluderNode>
#include <osg/Transform>
#include <osg/UserDataContainer>

#include <algorithm>

using namespace osg;

namespace osg
{
/// Helper class for generating NodePathList.
class CollectParentPaths : public NodeVisitor
{
public:
CollectParentPaths(const osg::Node* haltTraversalAtNode=0) :
osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_PARENTS),
_haltTraversalAtNode(haltTraversalAtNode)
{
setNodeMaskOverride(0xffffffff);
}

virtual void apply(osg::Node& node)
{
if (node.getNumParents()==0 || &node==_haltTraversalAtNode)
{
_nodePaths.push_back(getNodePath());
}
else
{
traverse(node);
}
}

const Node* _haltTraversalAtNode;
NodePath _nodePath;
NodePathList _nodePaths;
};
}



Node::Node()
:Object(true)
{
_boundingSphereComputed = false;
_nodeMask = 0xffffffff;

_numChildrenRequiringUpdateTraversal = 0;

_numChildrenRequiringEventTraversal = 0;

_cullingActive = true;
_numChildrenWithCullingDisabled = 0;

_numChildrenWithOccluderNodes = 0;
}

Node::Node(const Node& node,const CopyOp& copyop):
Object(node,copyop),
_initialBound(node._initialBound),
_boundingSphere(node._boundingSphere),
_boundingSphereComputed(node._boundingSphereComputed),
_parents(), // leave empty as parentList is managed by Group.
_updateCallback(copyop(node._updateCallback.get())),
_numChildrenRequiringUpdateTraversal(0), // assume no children yet.
_numChildrenRequiringEventTraversal(0), // assume no children yet.
_cullCallback(copyop(node._cullCallback.get())),
_cullingActive(node._cullingActive),
_numChildrenWithCullingDisabled(0), // assume no children yet.
_numChildrenWithOccluderNodes(0),
_nodeMask(node._nodeMask)
{
setStateSet(copyop(node._stateset.get()));
}

Node::~Node()
{
// cleanly detatch any associated stateset (include remove parent links)
setStateSet(0);
}

void Node::addParent(osg::Group* parent)
{
OpenThreads::ScopedPointerLock<OpenThreads::Mutex> lock(getRefMutex());

_parents.push_back(parent);
}

void Node::removeParent(osg::Group* parent)
{
OpenThreads::ScopedPointerLock<OpenThreads::Mutex> lock(getRefMutex());

ParentList::iterator pitr = std::find(_parents.begin(), _parents.end(), parent);
if (pitr!=_parents.end()) _parents.erase(pitr);
}

void Node::accept(NodeVisitor& nv)
{
if (nv.validNodeMask(*this))
{
nv.pushOntoNodePath(this);
nv.apply(*this);
nv.popFromNodePath();
}
}


void Node::ascend(NodeVisitor& nv)
{
std::for_each(_parents.begin(),_parents.end(),NodeAcceptOp(nv));
}

void Node::setStateSet(osg::StateSet* stateset)
{
// do nothing if nothing changed.
if (_stateset==stateset) return;

// track whether we need to account for the need to do a update or event traversal.
int delta_update = 0;
int delta_event = 0;

// remove this node from the current statesets parent list
if (_stateset.valid())
{
_stateset->removeParent(this);
if (_stateset->requiresUpdateTraversal()) --delta_update;
if (_stateset->requiresEventTraversal()) --delta_event;
}

// set the stateset.
_stateset = stateset;

// add this node to the new stateset to the parent list.
if (_stateset.valid())
{
_stateset->addParent(this);
if (_stateset->requiresUpdateTraversal()) ++delta_update;
if (_stateset->requiresEventTraversal()) ++delta_event;
}

if (delta_update!=0)
{
setNumChildrenRequiringUpdateTraversal(getNumChildrenRequiringUpdateTraversal()+delta_update);
}

if (delta_event!=0)
{
setNumChildrenRequiringEventTraversal(getNumChildrenRequiringEventTraversal()+delta_event);
}
}

osg::StateSet* Node::getOrCreateStateSet()
{
if (!_stateset) setStateSet(new StateSet);
return _stateset.get();
}

NodePathList Node::getParentalNodePaths(osg::Node* haltTraversalAtNode) const
{
CollectParentPaths cpp(haltTraversalAtNode);
const_cast<Node*>(this)->accept(cpp);
return cpp._nodePaths;
}

MatrixList Node::getWorldMatrices(const osg::Node* haltTraversalAtNode) const
{
CollectParentPaths cpp(haltTraversalAtNode);
const_cast<Node*>(this)->accept(cpp);

MatrixList matrices;

for(NodePathList::iterator itr = cpp._nodePaths.begin();
itr != cpp._nodePaths.end();
++itr)
{
NodePath& nodePath = *itr;
if (nodePath.empty())
{
matrices.push_back(osg::Matrix::identity());
}
else
{
matrices.push_back(osg::computeLocalToWorld(nodePath));
}
}

return matrices;
}

void Node::setUpdateCallback(Callback* nc)
{
// if no changes just return.
if (_updateCallback==nc) return;

// updated callback has been changed, will need to update
// both _updateCallback and possibly the numChildrenRequiringAppTraversal
// if the number of callbacks changes.


// update the parents numChildrenRequiringAppTraversal
// note, if _numChildrenRequiringUpdateTraversal!=0 then the
// parents won't be affected by any app callback change,
// so no need to inform them.
if (_numChildrenRequiringUpdateTraversal==0 && !_parents.empty())
{
int delta = 0;
if (_updateCallback.valid()) --delta;
if (nc) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenRequiringUpdateTraversal(
(*itr)->getNumChildrenRequiringUpdateTraversal()+delta );
}

}
}

// set the app callback itself.
_updateCallback = nc;

}

void Node::setNumChildrenRequiringUpdateTraversal(unsigned int num)
{
// if no changes just return.
if (_numChildrenRequiringUpdateTraversal==num) return;

// note, if _updateCallback is set then the
// parents won't be affected by any changes to
// _numChildrenRequiringUpdateTraversal so no need to inform them.
if (!_updateCallback && !_parents.empty())
{

// need to pass on changes to parents.
int delta = 0;
if (_numChildrenRequiringUpdateTraversal>0) --delta;
if (num>0) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenRequiringUpdateTraversal(
(*itr)->getNumChildrenRequiringUpdateTraversal()+delta
);
}

}
}

// finally update this objects value.
_numChildrenRequiringUpdateTraversal=num;

}


void Node::setEventCallback(Callback* nc)
{
// if no changes just return.
if (_eventCallback==nc) return;

// event callback has been changed, will need to Event
// both _EventCallback and possibly the numChildrenRequiringAppTraversal
// if the number of callbacks changes.


// Event the parents numChildrenRequiringAppTraversal
// note, if _numChildrenRequiringEventTraversal!=0 then the
// parents won't be affected by any app callback change,
// so no need to inform them.
if (_numChildrenRequiringEventTraversal==0 && !_parents.empty())
{
int delta = 0;
if (_eventCallback.valid()) --delta;
if (nc) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenRequiringEventTraversal(
(*itr)->getNumChildrenRequiringEventTraversal()+delta );
}

}
}

// set the app callback itself.
_eventCallback = nc;

}

void Node::setNumChildrenRequiringEventTraversal(unsigned int num)
{
// if no changes just return.
if (_numChildrenRequiringEventTraversal==num) return;

// note, if _EventCallback is set then the
// parents won't be affected by any changes to
// _numChildrenRequiringEventTraversal so no need to inform them.
if (!_eventCallback && !_parents.empty())
{

// need to pass on changes to parents.
int delta = 0;
if (_numChildrenRequiringEventTraversal>0) --delta;
if (num>0) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenRequiringEventTraversal(
(*itr)->getNumChildrenRequiringEventTraversal()+delta
);
}

}
}

// finally Event this objects value.
_numChildrenRequiringEventTraversal=num;

}

void Node::setCullingActive(bool active)
{
// if no changes just return.
if (_cullingActive == active) return;

// culling active has been changed, will need to update
// both _cullActive and possibly the parents numChildrenWithCullingDisabled
// if culling disabled changes.

// update the parents _numChildrenWithCullingDisabled
// note, if _numChildrenWithCullingDisabled!=0 then the
// parents won't be affected by any app callback change,
// so no need to inform them.
if (_numChildrenWithCullingDisabled==0 && !_parents.empty())
{
int delta = 0;
if (!_cullingActive) --delta;
if (!active) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenWithCullingDisabled(
(*itr)->getNumChildrenWithCullingDisabled()+delta );
}

}
}

// set the cullingActive itself.
_cullingActive = active;
}

void Node::setNumChildrenWithCullingDisabled(unsigned int num)
{
// if no changes just return.
if (_numChildrenWithCullingDisabled==num) return;

// note, if _cullingActive is false then the
// parents won't be affected by any changes to
// _numChildrenWithCullingDisabled so no need to inform them.
if (_cullingActive && !_parents.empty())
{

// need to pass on changes to parents.
int delta = 0;
if (_numChildrenWithCullingDisabled>0) --delta;
if (num>0) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenWithCullingDisabled(
(*itr)->getNumChildrenWithCullingDisabled()+delta
);
}

}
}

// finally update this objects value.
_numChildrenWithCullingDisabled=num;
}


void Node::setNumChildrenWithOccluderNodes(unsigned int num)
{
// if no changes just return.
if (_numChildrenWithOccluderNodes==num) return;

// note, if this node is a OccluderNode then the
// parents won't be affected by any changes to
// _numChildrenWithOccluderNodes so no need to inform them.
if (!dynamic_cast<OccluderNode*>(this) && !_parents.empty())
{

// need to pass on changes to parents.
int delta = 0;
if (_numChildrenWithOccluderNodes>0) --delta;
if (num>0) ++delta;
if (delta!=0)
{
// the number of callbacks has changed, need to pass this
// on to parents so they know whether app traversal is
// required on this subgraph.
for(ParentList::iterator itr =_parents.begin();
itr != _parents.end();
++itr)
{
(*itr)->setNumChildrenWithOccluderNodes(
(*itr)->getNumChildrenWithOccluderNodes()+delta
);
}

}
}

// finally update this objects value.
_numChildrenWithOccluderNodes=num;

}

bool Node::containsOccluderNodes() const
{
return _numChildrenWithOccluderNodes>0 || dynamic_cast<const OccluderNode*>(this);
}

void Node::setDescriptions(const DescriptionList& descriptions)
{
// only assign a description list (and associated UseDataContainer) if we need to.
if (!descriptions.empty() || getUserDataContainer())
{
getOrCreateUserDataContainer()->setDescriptions(descriptions);
}
}

Node::DescriptionList& Node::getDescriptions()
{
return getOrCreateUserDataContainer()->getDescriptions();
}

static OpenThreads::Mutex s_mutex_StaticDescriptionList;
static const Node::DescriptionList& getStaticDescriptionList()
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock(s_mutex_StaticDescriptionList);
static Node::DescriptionList s_descriptionList;
return s_descriptionList;
}

const Node::DescriptionList& Node::getDescriptions() const
{
if (_userDataContainer) return _userDataContainer->getDescriptions();
else return getStaticDescriptionList();
}

std::string& Node::getDescription(unsigned int i)
{
return getOrCreateUserDataContainer()->getDescriptions()[i];
}

const std::string& Node::getDescription(unsigned int i) const
{
if (_userDataContainer) return _userDataContainer->getDescriptions()[i];
else return getStaticDescriptionList()[i];
}

unsigned int Node::getNumDescriptions() const
{
return _userDataContainer ? _userDataContainer->getDescriptions().size() : 0;
}

void Node::addDescription(const std::string& desc)
{
getOrCreateUserDataContainer()->getDescriptions().push_back(desc);
}

BoundingSphere Node::computeBound() const
{
return BoundingSphere();
}


void Node::dirtyBound()
{
if (_boundingSphereComputed)
{
_boundingSphereComputed = false;

// dirty parent bounding sphere's to ensure that all are valid.
for(ParentList::iterator itr=_parents.begin();
itr!=_parents.end();
++itr)
{
(*itr)->dirtyBound();
}

}
}

void Node::setThreadSafeRefUnref(bool threadSafe)
{
Object::setThreadSafeRefUnref(threadSafe);

if (_stateset.valid()) _stateset->setThreadSafeRefUnref(threadSafe);
if (_updateCallback.valid()) _updateCallback->setThreadSafeRefUnref(threadSafe);
if (_eventCallback.valid()) _eventCallback->setThreadSafeRefUnref(threadSafe);
if (_cullCallback.valid()) _cullCallback->setThreadSafeRefUnref(threadSafe);
}

void Node::resizeGLObjectBuffers(unsigned int maxSize)
{
if (_stateset.valid()) _stateset->resizeGLObjectBuffers(maxSize);
if (_updateCallback.valid()) _updateCallback->resizeGLObjectBuffers(maxSize);
if (_eventCallback.valid()) _eventCallback->resizeGLObjectBuffers(maxSize);
if (_cullCallback.valid()) _cullCallback->resizeGLObjectBuffers(maxSize);
}

void Node::releaseGLObjects(osg::State* state) const
{
if (_stateset.valid()) _stateset->releaseGLObjects(state);
if (_updateCallback.valid()) _updateCallback->releaseGLObjects(state);
if (_eventCallback.valid()) _eventCallback->releaseGLObjects(state);
if (_cullCallback.valid()) _cullCallback->releaseGLObjects(state);
}