/*

-----------------------------------------------------------------------------

This source file is part of OGRE

    (Object-oriented Graphics Rendering Engine)

For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2014 Torus Knot Software Ltd

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

-----------------------------------------------------------------------------

*/

#include "OgreStableHeaders.h"

namespace Ogre {

    //-----------------------------------------------------------------------

    SceneNode::SceneNode(SceneManager* creator, const String& name)

        : Node(name)

        , mCreator(creator)

        , mAutoTrackTarget(0)

        , mGlobalIndex(-1)

        , mYawFixed(false)

        , mIsInSceneGraph(false)

        , mShowBoundingBox(false)

    {

        needUpdate();

    }

    //-----------------------------------------------------------------------

    SceneNode::~SceneNode()

    {

        // Detach all objects, do this manually to avoid needUpdate() call 

        // which can fail because of deleted items

        for (auto & itr : mObjectsByName)

        {

            itr->_notifyAttached((SceneNode*)0);

        }

        mObjectsByName.clear();

    }

    //-----------------------------------------------------------------------

    void SceneNode::_update(bool updateChildren, bool parentHasChanged)

    {

        Node::_update(updateChildren, parentHasChanged);

        _updateBounds();

    }

    //-----------------------------------------------------------------------

    void SceneNode::setParent(Node* parent)

    {

        Node::setParent(parent);

        if (parent)

        {

            SceneNode* sceneParent = static_cast<SceneNode*>(parent);

            setInSceneGraph(sceneParent->isInSceneGraph());

        }

        else

        {

            setInSceneGraph(false);

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::setInSceneGraph(bool inGraph)

    {

        if (inGraph != mIsInSceneGraph)

        {

            mIsInSceneGraph = inGraph;

            // Tell children

            for (auto child : getChildren())

            {

                SceneNode* sceneChild = static_cast<SceneNode*>(child);

                sceneChild->setInSceneGraph(inGraph);

            }

        }

    }

    //-----------------------------------------------------------------------

    struct MovableObjectNameExists {

        const String& name;

        bool operator()(const MovableObject* mo) {

            return mo->getName() == name;

        }

    };

    void SceneNode::attachObject(MovableObject* obj)

    {

        OgreAssert(!obj->isAttached(), "Object already attached to a SceneNode or a Bone");

        obj->_notifyAttached(this);

        // Also add to name index

        MovableObjectNameExists pred = {obj->getName()};

        ObjectMap::iterator it = std::find_if(mObjectsByName.begin(), mObjectsByName.end(), pred);

        if (it != mObjectsByName.end())

            OGRE_EXCEPT(Exception::ERR_DUPLICATE_ITEM,

                        "An object named '" + obj->getName() + "' already attached to this SceneNode");

        mObjectsByName.push_back(obj);

        // Make sure bounds get updated (must go right to the top)

        needUpdate();

    }

    //-----------------------------------------------------------------------

    MovableObject* SceneNode::getAttachedObject(const String& name) const

    {

        // Look up 

        MovableObjectNameExists pred = {name};

        auto i = std::find_if(mObjectsByName.begin(), mObjectsByName.end(), pred);

        if (i == mObjectsByName.end())

        {

            OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND, "Attached object " + 

                name + " not found.", "SceneNode::getAttachedObject");

        }

        return *i;

    }

    //-----------------------------------------------------------------------

    MovableObject* SceneNode::detachObject(unsigned short index)

    {

        OgreAssert(index < mObjectsByName.size(), "out of bounds");

        ObjectMap::iterator i = mObjectsByName.begin();

        i += index;

        MovableObject* ret = *i;

        std::swap(*i, mObjectsByName.back());

        mObjectsByName.pop_back();

        ret->_notifyAttached((SceneNode*)0);

        // Make sure bounds get updated (must go right to the top)

        needUpdate();

        return ret;

    }

    //-----------------------------------------------------------------------

    MovableObject* SceneNode::detachObject(const String& name)

    {

        MovableObjectNameExists pred = {name};

        ObjectMap::iterator it = std::find_if(mObjectsByName.begin(), mObjectsByName.end(), pred);

        if (it == mObjectsByName.end())

        {

            OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND, "Object " + name + " is not attached "

                "to this node.", "SceneNode::detachObject");

        }

        MovableObject* ret = *it;

        std::swap(*it, mObjectsByName.back());

        mObjectsByName.pop_back();

        ret->_notifyAttached((SceneNode*)0);

        // Make sure bounds get updated (must go right to the top)

        needUpdate();

        return ret;

    }

    //-----------------------------------------------------------------------

    void SceneNode::detachObject(MovableObject* obj)

    {

        auto it = std::find(mObjectsByName.begin(), mObjectsByName.end(), obj);

        OgreAssert(it != mObjectsByName.end(), "Object is not attached to this node");

        std::swap(*it, mObjectsByName.back());

        mObjectsByName.pop_back();

        obj->_notifyAttached((SceneNode*)0);

        // Make sure bounds get updated (must go right to the top)

        needUpdate();

    }

    //-----------------------------------------------------------------------

    void SceneNode::detachAllObjects(void)

    {

        for (auto & itr : mObjectsByName)

        {

            itr->_notifyAttached((SceneNode*)0);

        }

        mObjectsByName.clear();

        // Make sure bounds get updated (must go right to the top)

        needUpdate();

    }

    //-----------------------------------------------------------------------

    void SceneNode::destroyAllObjects(void)

    {

        while (!getAttachedObjects().empty()) {

            auto obj = getAttachedObjects().front();

            getCreator()->destroyMovableObject(obj);

        }

        needUpdate();

    }

    //-----------------------------------------------------------------------

    void SceneNode::_updateBounds(void)

    {

        // Reset bounds first

        mWorldAABB.setNull();

        // Update bounds from own attached objects

        for (auto *o : mObjectsByName)

        {

            // Merge world bounds of each object

            mWorldAABB.merge(o->getWorldBoundingBox(true));

        }

        // Merge with children

        for (auto child : getChildren())

        {

            SceneNode* sceneChild = static_cast<SceneNode*>(child);

            mWorldAABB.merge(sceneChild->mWorldAABB);

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::_findVisibleObjects(Camera* cam, RenderQueue* queue, 

        VisibleObjectsBoundsInfo* visibleBounds, bool includeChildren, 

        bool displayNodes, bool onlyShadowCasters)

    {

        // Check self visible

        if (!cam->isVisible(mWorldAABB))

            return;

        // Add all entities

        for (auto *o : mObjectsByName)

        {

            queue->processVisibleObject(o, cam, onlyShadowCasters, visibleBounds);

        }

        if (includeChildren)

        {

            for (auto child : getChildren())

            {

                SceneNode* sceneChild = static_cast<SceneNode*>(child);

                sceneChild->_findVisibleObjects(cam, queue, visibleBounds, includeChildren, 

                    displayNodes, onlyShadowCasters);

            }

        }

        if (mCreator && mCreator->getDebugDrawer())

        {

            mCreator->getDebugDrawer()->drawSceneNode(this);

        }

    }

    SceneNode::ObjectIterator SceneNode::getAttachedObjectIterator(void) {

        return ObjectIterator(mObjectsByName.begin(), mObjectsByName.end());

    }

    SceneNode::ConstObjectIterator SceneNode::getAttachedObjectIterator(void) const {

        return ConstObjectIterator(mObjectsByName.begin(), mObjectsByName.end());

    }

    //-----------------------------------------------------------------------

    void SceneNode::updateFromParentImpl(void) const

    {

        Node::updateFromParentImpl();

        // Notify objects that it has been moved

        for (auto o : mObjectsByName)

        {

            o->_notifyMoved();

        }

    }

    //-----------------------------------------------------------------------

    Node* SceneNode::createChildImpl(void)

    {

        assert(mCreator);

        return mCreator->createSceneNode();

    }

    //-----------------------------------------------------------------------

    Node* SceneNode::createChildImpl(const String& name)

    {

        assert(mCreator);

        return mCreator->createSceneNode(name);

    }

    //-----------------------------------------------------------------------

    void SceneNode::removeAndDestroyChild(const String& name)

    {

        SceneNode* pChild = static_cast<SceneNode*>(removeChild(name));

        pChild->removeAndDestroyAllChildren();

        pChild->getCreator()->destroySceneNode(name);

    }

    //-----------------------------------------------------------------------

    void SceneNode::removeAndDestroyChild(unsigned short index)

    {

        SceneNode* pChild = static_cast<SceneNode*>(removeChild(index));

        pChild->removeAndDestroyAllChildren();

        pChild->getCreator()->destroySceneNode(pChild);

    }

    //-----------------------------------------------------------------------

    void SceneNode::removeAndDestroyChild(SceneNode* child)

    {

        auto it = std::find(getChildren().begin(), getChildren().end(), child);

        OgreAssert(it != getChildren().end(), "Not a child of this SceneNode");

        removeAndDestroyChild(it - getChildren().begin());

    }

    //-----------------------------------------------------------------------

    void SceneNode::removeAndDestroyAllChildren(void)

    {

        // do not store iterators (invalidated by

        // SceneManager::destroySceneNode because it causes removal from parent)

        while(!getChildren().empty()) {

            SceneNode* sn = static_cast<SceneNode*>(getChildren().front());

            sn->removeAndDestroyAllChildren();

            sn->getCreator()->destroySceneNode(sn);

        }

        mChildren.clear();

        needUpdate();

    }

    //-----------------------------------------------------------------------

    void SceneNode::destroyChildAndObjects(const String& name) {

        SceneNode* pChild = static_cast<SceneNode*>(getChild(name));

        pChild->destroyAllChildrenAndObjects();

        removeChild(name);

        pChild->getCreator()->destroySceneNode(name);

    }

    void SceneNode::destroyChildAndObjects(unsigned short index) {

        SceneNode* pChild = static_cast<SceneNode*>(removeChild(index));

        pChild->destroyAllChildrenAndObjects();

        pChild->getCreator()->destroySceneNode(pChild);

    }

    void SceneNode::destroyChildAndObjects(SceneNode * child)

    {

        auto it = std::find(getChildren().begin(), getChildren().end(), child);

        OgreAssert(it != getChildren().end(), "Not a child of this SceneNode");

        destroyChildAndObjects(it - getChildren().begin());

    }

    void SceneNode::destroyAllChildrenAndObjects()

    {

        //remove objects directly attached to this node

        destroyAllObjects();

        //go over children

        while(!getChildren().empty()) {

            SceneNode* child = static_cast<SceneNode*>(getChildren().front());

            //recurse

            child->destroyAllChildrenAndObjects();

            //destroy child

            child->getCreator()->destroySceneNode(child);

        }

        mChildren.clear();

        needUpdate();

    }

    //-----------------------------------------------------------------------

    void SceneNode::loadChildren(const String& filename)

    {

        String baseName, strExt;

        StringUtil::splitBaseFilename(filename, baseName, strExt);

        auto codec = Codec::getCodec(strExt);

        if (!codec)

            OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, "No codec found to load " + filename);

        auto stream = Root::openFileStream(

            filename, ResourceGroupManager::getSingleton().getWorldResourceGroupName());

        codec->decode(stream, this);

    }

    void SceneNode::saveChildren(const String& filename)

    {

        String baseName, strExt;

        StringUtil::splitBaseFilename(filename, baseName, strExt);

        auto codec = Codec::getCodec(strExt);

        codec->encodeToFile(this, filename);

    }

    //-----------------------------------------------------------------------

    SceneNode* SceneNode::createChildSceneNode(const Vector3& inTranslate, 

        const Quaternion& inRotate)

    {

        return static_cast<SceneNode*>(this->createChild(inTranslate, inRotate));

    }

    //-----------------------------------------------------------------------

    SceneNode* SceneNode::createChildSceneNode(const String& name, const Vector3& inTranslate, 

        const Quaternion& inRotate)

    {

        return static_cast<SceneNode*>(this->createChild(name, inTranslate, inRotate));

    }

    //-----------------------------------------------------------------------

    void SceneNode::findLights(LightList& destList, Real radius, uint32 lightMask) const

    {

        // No any optimisation here, hope inherits more smart for that.

        //

        // If a scene node is static and lights have moved, light list won't change

        // can't use a simple global boolean flag since this is only called for

        // visible nodes, so temporarily visible nodes will not be updated

        // Since this is only called for visible nodes, skip the check for now

        //

        if (mCreator)

        {

            // Use SceneManager to calculate

            mCreator->_populateLightList(this, radius, destList, lightMask);

        }

        else

        {

            destList.clear();

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::setAutoTracking(bool enabled, SceneNode* const target, 

        const Vector3& localDirectionVector,

        const Vector3& offset)

    {

        if (enabled)

        {

            mAutoTrackTarget = target;

            mAutoTrackOffset = offset;

            mAutoTrackLocalDirection = localDirectionVector;

        }

        else

        {

            mAutoTrackTarget = 0;

        }

        if (mCreator)

            mCreator->_notifyAutotrackingSceneNode(this, enabled);

    }

    //-----------------------------------------------------------------------

    void SceneNode::setFixedYawAxis(bool useFixed, const Vector3& fixedAxis)

    {

        mYawFixed = useFixed;

        mYawFixedAxis = fixedAxis;

    }

    //-----------------------------------------------------------------------

    void SceneNode::yaw(const Radian& angle, TransformSpace relativeTo)

    {

        if (mYawFixed)

        {

            rotate(mYawFixedAxis, angle, relativeTo);

        }

        else

        {

            rotate(Vector3::UNIT_Y, angle, relativeTo);

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::setDirection(Real x, Real y, Real z, TransformSpace relativeTo, 

        const Vector3& localDirectionVector)

    {

        setDirection(Vector3(x,y,z), relativeTo, localDirectionVector);

    }

    //-----------------------------------------------------------------------

    void SceneNode::setDirection(const Vector3& vec, TransformSpace relativeTo, 

        const Vector3& localDirectionVector)

    {

        // Do nothing if given a zero vector

        if (vec == Vector3::ZERO) return;

        // The direction we want the local direction point to

        Vector3 targetDir = vec.normalisedCopy();

        // Transform target direction to world space

        switch (relativeTo)

        {

        case TS_PARENT:

            if (getInheritOrientation())

            {

                if (getParent())

                {

                    targetDir = getParent()->_getDerivedOrientation() * targetDir;

                }

            }

            break;

        case TS_LOCAL:

            targetDir = _getDerivedOrientation() * targetDir;

            break;

        case TS_WORLD:

            // default orientation

            break;

        }

        // Calculate target orientation relative to world space

        Quaternion targetOrientation;

        if( mYawFixed )

        {

            // Calculate the quaternion for rotate local Z to target direction

            Vector3 yawAxis = mYawFixedAxis;

            if (getInheritOrientation() && getParent())

            {

                yawAxis = getParent()->_getDerivedOrientation() * yawAxis;

            }

            Quaternion unitZToTarget = Math::lookRotation(targetDir, yawAxis);

            if (localDirectionVector == Vector3::NEGATIVE_UNIT_Z)

            {

                // Specail case for avoid calculate 180 degree turn

                targetOrientation =

                    Quaternion(-unitZToTarget.y, -unitZToTarget.z, unitZToTarget.w, unitZToTarget.x);

            }

            else

            {

                // Calculate the quaternion for rotate local direction to target direction

                Quaternion localToUnitZ = localDirectionVector.getRotationTo(Vector3::UNIT_Z);

                targetOrientation = unitZToTarget * localToUnitZ;

            }

        }

        else

        {

            const Quaternion& currentOrient = _getDerivedOrientation();

            // Get current local direction relative to world space

            Vector3 currentDir = currentOrient * localDirectionVector;

            if ((currentDir+targetDir).squaredLength() < 0.00005f)

            {

                // Oops, a 180 degree turn (infinite possible rotation axes)

                // Default to yaw i.e. use current UP

                targetOrientation =

                    Quaternion(-currentOrient.y, -currentOrient.z, currentOrient.w, currentOrient.x);

            }

            else

            {

                // Derive shortest arc to new direction

                Quaternion rotQuat = currentDir.getRotationTo(targetDir);

                targetOrientation = rotQuat * currentOrient;

            }

        }

        // Set target orientation, transformed to parent space

        if (getParent() && getInheritOrientation())

            setOrientation(getParent()->_getDerivedOrientation().UnitInverse() * targetOrientation);

        else

            setOrientation(targetOrientation);

    }

    //-----------------------------------------------------------------------

    void SceneNode::lookAt( const Vector3& targetPoint, TransformSpace relativeTo, 

        const Vector3& localDirectionVector)

    {

        // Calculate ourself origin relative to the given transform space

        Vector3 origin;

        switch (relativeTo)

        {

        default:    // Just in case

        case TS_WORLD:

            origin = _getDerivedPosition();

            break;

        case TS_PARENT:

            origin = getPosition();

            break;

        case TS_LOCAL:

            origin = Vector3::ZERO;

            break;

        }

        setDirection(targetPoint - origin, relativeTo, localDirectionVector);

    }

    //-----------------------------------------------------------------------

    void SceneNode::_autoTrack(void)

    {

        // NB assumes that all scene nodes have been updated

        if (mAutoTrackTarget)

        {

            lookAt(mAutoTrackTarget->_getDerivedPosition() + mAutoTrackOffset, 

                TS_WORLD, mAutoTrackLocalDirection);

            // update self & children

            _update(true, true);

        }

    }

    //-----------------------------------------------------------------------

    SceneNode* SceneNode::getParentSceneNode(void) const

    {

        return static_cast<SceneNode*>(getParent());

    }

    //-----------------------------------------------------------------------

    void SceneNode::setVisible(bool visible, bool cascade) const

    {

        for (auto o : mObjectsByName)

        {

            o->setVisible(visible);

        }

        if (cascade)

        {

            for (auto c : getChildren())

            {

                static_cast<SceneNode*>(c)->setVisible(visible, cascade);

            }

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::setDebugDisplayEnabled(bool enabled, bool cascade) const

    {

        for (auto o : mObjectsByName)

        {

            o->setDebugDisplayEnabled(enabled);

        }

        if (cascade)

        {

            for (auto c : getChildren())

            {

                static_cast<SceneNode*>(c)->setDebugDisplayEnabled(enabled, cascade);

            }

        }

    }

    //-----------------------------------------------------------------------

    void SceneNode::flipVisibility(bool cascade) const

    {

        for (auto o : mObjectsByName)

        {

            o->setVisible(!o->getVisible());

        }

        if (cascade)

        {

            for (auto c : getChildren())

            {

                static_cast<SceneNode*>(c)->flipVisibility(cascade);

            }

        }

    }

}