/*
  OpenMW - The completely unofficial reimplementation of Morrowind
  Copyright (C) 2008-2010  Nicolay Korslund
  Email: < korslund@gmail.com >
  WWW: http://openmw.sourceforge.net/

  This file (ogre_nif_loader.cpp) is part of the OpenMW package.

  OpenMW is distributed as free software: you can redistribute it
  and/or modify it under the terms of the GNU General Public License
  version 3, 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
  version 3 along with this program. If not, see
  http://www.gnu.org/licenses/ .

 */

#include "ogrenifloader.hpp"

#include <algorithm>

#include <OgreMaterialManager.h>
#include <OgreMeshManager.h>
#include <OgreHardwareBufferManager.h>
#include <OgreSkeletonManager.h>
#include <OgreTechnique.h>
#include <OgreSubMesh.h>
#include <OgreRoot.h>
#include <OgreEntity.h>
#include <OgreSubEntity.h>
#include <OgreTagPoint.h>
#include <OgreParticleSystem.h>
#include <OgreParticleEmitter.h>
#include <OgreParticleAffector.h>
#include <OgreControllerManager.h>

#include <components/nif/node.hpp>
#include <components/misc/stringops.hpp>

#include "skeleton.hpp"
#include "material.hpp"

namespace std
{

// TODO: Do something useful
ostream& operator<<(ostream &o, const NifOgre::TextKeyMap&)
{ return o; }

}

namespace NifOgre
{

// FIXME: Should not be here.
class DefaultFunction : public Ogre::ControllerFunction<Ogre::Real>
{
private:
    float mFrequency;
    float mPhase;
    float mStartTime;
    float mStopTime;

public:
    DefaultFunction(const Nif::Controller *ctrl, bool deltaInput)
        : Ogre::ControllerFunction<Ogre::Real>(deltaInput)
        , mFrequency(ctrl->frequency)
        , mPhase(ctrl->phase)
        , mStartTime(ctrl->timeStart)
        , mStopTime(ctrl->timeStop)
    {
        if(mDeltaInput)
        {
            mDeltaCount = mPhase;
            while(mDeltaCount < mStartTime)
                mDeltaCount += (mStopTime-mStartTime);
        }
    }

    virtual Ogre::Real calculate(Ogre::Real value)
    {
        if(mDeltaInput)
        {
            mDeltaCount += value*mFrequency;
            mDeltaCount = std::fmod(mDeltaCount - mStartTime,
                                    mStopTime - mStartTime) + mStartTime;
            return mDeltaCount;
        }

        value = std::min(mStopTime, std::max(mStartTime, value+mPhase));
        return value;
    }
};

class VisController
{
public:
    class Value : public NodeTargetValue<Ogre::Real>
    {
    private:
        std::vector<Nif::NiVisData::VisData> mData;

        virtual bool calculate(Ogre::Real time)
        {
            if(mData.size() == 0)
                return true;

            for(size_t i = 1;i < mData.size();i++)
            {
                if(mData[i].time > time)
                    return mData[i-1].isSet;
            }
            return mData.back().isSet;
        }

        // FIXME: We are not getting all objects here. Skinned meshes get
        // attached to the object's root node, and won't be connected via a
        // TagPoint.
        static void setVisible(Ogre::Node *node, int vis)
        {
            Ogre::Node::ChildNodeIterator iter = node->getChildIterator();
            while(iter.hasMoreElements())
            {
                node = iter.getNext();
                setVisible(node, vis);

                Ogre::TagPoint *tag = dynamic_cast<Ogre::TagPoint*>(node);
                if(tag != NULL)
                {
                    Ogre::MovableObject *obj = tag->getChildObject();
                    if(obj != NULL)
                        obj->setVisible(vis);
                }
            }
        }

    public:
        Value(Ogre::Node *target, const Nif::NiVisData *data)
          : NodeTargetValue<Ogre::Real>(target)
          , mData(data->mVis)
        { }

        virtual Ogre::Real getValue() const
        {
            // Should not be called
            return 1.0f;
        }

        virtual void setValue(Ogre::Real time)
        {
            bool vis = calculate(time);
            setVisible(mNode, vis);
        }
    };

    typedef DefaultFunction Function;
};

class KeyframeController
{
public:
    class Value : public NodeTargetValue<Ogre::Real>
    {
    private:
        Nif::QuaternionKeyList mRotations;
        Nif::Vector3KeyList mTranslations;
        Nif::FloatKeyList mScales;

    public:
        Value(Ogre::Node *target, const Nif::NiKeyframeData *data)
          : NodeTargetValue<Ogre::Real>(target)
          , mRotations(data->mRotations)
          , mTranslations(data->mTranslations)
          , mScales(data->mScales)
        { }

        virtual Ogre::Real getValue() const
        {
            // Should not be called
            return 0.0f;
        }

        virtual void setValue(Ogre::Real time)
        {
            if(mRotations.mKeys.size() > 0)
            {
                if(time <= mRotations.mKeys.front().mTime)
                    mNode->setOrientation(mRotations.mKeys.front().mValue);
                else if(time >= mRotations.mKeys.back().mTime)
                    mNode->setOrientation(mRotations.mKeys.back().mValue);
                else
                {
                    Nif::QuaternionKeyList::VecType::const_iterator iter(mRotations.mKeys.begin()+1);
                    for(;iter != mRotations.mKeys.end();iter++)
                    {
                        if(iter->mTime < time)
                            continue;

                        Nif::QuaternionKeyList::VecType::const_iterator last(iter-1);
                        float a = (time-last->mTime) / (iter->mTime-last->mTime);
                        mNode->setOrientation(Ogre::Quaternion::nlerp(a, last->mValue, iter->mValue));
                        break;
                    }
                }
            }
            if(mTranslations.mKeys.size() > 0)
            {
                if(time <= mTranslations.mKeys.front().mTime)
                    mNode->setPosition(mTranslations.mKeys.front().mValue);
                else if(time >= mTranslations.mKeys.back().mTime)
                    mNode->setPosition(mTranslations.mKeys.back().mValue);
                else
                {
                    Nif::Vector3KeyList::VecType::const_iterator iter(mTranslations.mKeys.begin()+1);
                    for(;iter != mTranslations.mKeys.end();iter++)
                    {
                        if(iter->mTime < time)
                            continue;

                        Nif::Vector3KeyList::VecType::const_iterator last(iter-1);
                        float a = (time-last->mTime) / (iter->mTime-last->mTime);
                        mNode->setPosition(last->mValue + ((iter->mValue - last->mValue)*a));
                        break;
                    }
                }
            }
            if(mScales.mKeys.size() > 0)
            {
                if(time <= mScales.mKeys.front().mTime)
                    mNode->setScale(Ogre::Vector3(mScales.mKeys.front().mValue));
                else if(time >= mScales.mKeys.back().mTime)
                    mNode->setScale(Ogre::Vector3(mScales.mKeys.back().mValue));
                else
                {
                    Nif::FloatKeyList::VecType::const_iterator iter(mScales.mKeys.begin()+1);
                    for(;iter != mScales.mKeys.end();iter++)
                    {
                        if(iter->mTime < time)
                            continue;

                        Nif::FloatKeyList::VecType::const_iterator last(iter-1);
                        float a = (time-last->mTime) / (iter->mTime-last->mTime);
                        mNode->setScale(Ogre::Vector3(last->mValue + ((iter->mValue - last->mValue)*a)));
                        break;
                    }
                }
            }
        }
    };

    typedef DefaultFunction Function;
};

class UVController
{
public:
    class Value : public Ogre::ControllerValue<Ogre::Real>
    {
    private:
        Ogre::MaterialPtr mMaterial;
        Nif::FloatKeyList mUTrans;
        Nif::FloatKeyList mVTrans;
        Nif::FloatKeyList mUScale;
        Nif::FloatKeyList mVScale;

        static float lookupValue(const Nif::FloatKeyList &keys, float time, float def)
        {
            if(keys.mKeys.size() == 0)
                return def;

            if(time <= keys.mKeys.front().mTime)
                return keys.mKeys.front().mValue;

            Nif::FloatKeyList::VecType::const_iterator iter(keys.mKeys.begin()+1);
            for(;iter != keys.mKeys.end();iter++)
            {
                if(iter->mTime < time)
                    continue;

                Nif::FloatKeyList::VecType::const_iterator last(iter-1);
                float a = (time-last->mTime) / (iter->mTime-last->mTime);
                return last->mValue + ((iter->mValue - last->mValue)*a);
            }
            return keys.mKeys.back().mValue;
        }

    public:
        Value(const Ogre::MaterialPtr &material, Nif::NiUVData *data)
          : mMaterial(material)
          , mUTrans(data->mKeyList[0])
          , mVTrans(data->mKeyList[1])
          , mUScale(data->mKeyList[2])
          , mVScale(data->mKeyList[3])
        { }

        virtual Ogre::Real getValue() const
        {
            // Should not be called
            return 1.0f;
        }

        virtual void setValue(Ogre::Real value)
        {
            float uTrans = lookupValue(mUTrans, value, 0.0f);
            float vTrans = lookupValue(mVTrans, value, 0.0f);
            float uScale = lookupValue(mUScale, value, 1.0f);
            float vScale = lookupValue(mVScale, value, 1.0f);

            Ogre::Material::TechniqueIterator techs = mMaterial->getTechniqueIterator();
            while(techs.hasMoreElements())
            {
                Ogre::Technique *tech = techs.getNext();
                Ogre::Technique::PassIterator passes = tech->getPassIterator();
                while(passes.hasMoreElements())
                {
                    Ogre::Pass *pass = passes.getNext();
                    Ogre::TextureUnitState *tex = pass->getTextureUnitState(0);
                    tex->setTextureScroll(uTrans, vTrans);
                    tex->setTextureScale(uScale, vScale);
                }
            }
        }
    };

    typedef DefaultFunction Function;
};


// Helper class that computes the bounding box and of a mesh
class BoundsFinder
{
    struct MaxMinFinder
    {
        float max, min;

        MaxMinFinder()
        {
            min = std::numeric_limits<float>::infinity();
            max = -min;
        }

        void add(float f)
        {
            if (f > max) max = f;
            if (f < min) min = f;
        }

        // Return Max(max**2, min**2)
        float getMaxSquared()
        {
            float m1 = max*max;
            float m2 = min*min;
            if (m1 >= m2) return m1;
            return m2;
        }
    };

    MaxMinFinder X, Y, Z;

public:
    // Add 'verts' vertices to the calculation. The 'data' pointer is
    // expected to point to 3*verts floats representing x,y,z for each
    // point.
    void add(float *data, int verts)
    {
        for (int i=0;i<verts;i++)
        {
            X.add(*(data++));
            Y.add(*(data++));
            Z.add(*(data++));
        }
    }

    // True if this structure has valid values
    bool isValid()
    {
        return
            minX() <= maxX() &&
            minY() <= maxY() &&
            minZ() <= maxZ();
    }

    // Compute radius
    float getRadius()
    {
        assert(isValid());

        // The radius is computed from the origin, not from the geometric
        // center of the mesh.
        return sqrt(X.getMaxSquared() + Y.getMaxSquared() + Z.getMaxSquared());
    }

    float minX() {
        return X.min;
    }
    float maxX() {
        return X.max;
    }
    float minY() {
        return Y.min;
    }
    float maxY() {
        return Y.max;
    }
    float minZ() {
        return Z.min;
    }
    float maxZ() {
        return Z.max;
    }
};


/** Manual resource loader for NIF objects (meshes, particle systems, etc).
 * This is the main class responsible for translating the internal NIF
 * structures into something Ogre can use.
 */
class NIFObjectLoader : Ogre::ManualResourceLoader
{
    std::string mName;
    std::string mGroup;
    size_t mShapeIndex;

    static void warn(const std::string &msg)
    {
        std::cerr << "NIFObjectLoader: Warn: " << msg << std::endl;
    }

    static void fail(const std::string &msg)
    {
        std::cerr << "NIFObjectLoader: Fail: "<< msg << std::endl;
        abort();
    }

    static void getNodeProperties(const Nif::Node *node,
                                  const Nif::NiTexturingProperty *&texprop,
                                  const Nif::NiMaterialProperty *&matprop,
                                  const Nif::NiAlphaProperty *&alphaprop,
                                  const Nif::NiVertexColorProperty *&vertprop,
                                  const Nif::NiZBufferProperty *&zprop,
                                  const Nif::NiSpecularProperty *&specprop,
                                  const Nif::NiWireframeProperty *&wireprop)
    {
        if(node->parent)
            getNodeProperties(node->parent, texprop, matprop, alphaprop, vertprop, zprop, specprop, wireprop);

        const Nif::PropertyList &proplist = node->props;
        for(size_t i = 0;i < proplist.length();i++)
        {
            // Entries may be empty
            if(proplist[i].empty())
                continue;

            const Nif::Property *pr = proplist[i].getPtr();
            if(pr->recType == Nif::RC_NiTexturingProperty)
                texprop = static_cast<const Nif::NiTexturingProperty*>(pr);
            else if(pr->recType == Nif::RC_NiMaterialProperty)
                matprop = static_cast<const Nif::NiMaterialProperty*>(pr);
            else if(pr->recType == Nif::RC_NiAlphaProperty)
                alphaprop = static_cast<const Nif::NiAlphaProperty*>(pr);
            else if(pr->recType == Nif::RC_NiVertexColorProperty)
                vertprop = static_cast<const Nif::NiVertexColorProperty*>(pr);
            else if(pr->recType == Nif::RC_NiZBufferProperty)
                zprop = static_cast<const Nif::NiZBufferProperty*>(pr);
            else if(pr->recType == Nif::RC_NiSpecularProperty)
                specprop = static_cast<const Nif::NiSpecularProperty*>(pr);
            else if(pr->recType == Nif::RC_NiWireframeProperty)
                wireprop = static_cast<const Nif::NiWireframeProperty*>(pr);
            else
                warn("Unhandled property type: "+pr->recName);
        }
    }

    // Convert NiTriShape to Ogre::SubMesh
    void createSubMesh(Ogre::Mesh *mesh, const Nif::NiTriShape *shape)
    {
        Ogre::SkeletonPtr skel;
        const Nif::NiTriShapeData *data = shape->data.getPtr();
        const Nif::NiSkinInstance *skin = (shape->skin.empty() ? NULL : shape->skin.getPtr());
        std::vector<Ogre::Vector3> srcVerts = data->vertices;
        std::vector<Ogre::Vector3> srcNorms = data->normals;
        Ogre::HardwareBuffer::Usage vertUsage = Ogre::HardwareBuffer::HBU_STATIC;
        bool vertShadowBuffer = false;
        if(skin != NULL)
        {
            vertUsage = Ogre::HardwareBuffer::HBU_DYNAMIC_WRITE_ONLY;
            vertShadowBuffer = true;

            // Only set a skeleton when skinning. Unskinned meshes with a skeleton will be
            // explicitly attached later.
            mesh->setSkeletonName(mName);

            // Get the skeleton resource, so vertices can be transformed into the bones' initial state.
            Ogre::SkeletonManager *skelMgr = Ogre::SkeletonManager::getSingletonPtr();
            skel = skelMgr->getByName(mName);

            // Convert vertices and normals to bone space from bind position. It would be
            // better to transform the bones into bind position, but there doesn't seem to
            // be a reliable way to do that.
            std::vector<Ogre::Vector3> newVerts(srcVerts.size(), Ogre::Vector3(0.0f));
            std::vector<Ogre::Vector3> newNorms(srcNorms.size(), Ogre::Vector3(0.0f));

            const Nif::NiSkinData *data = skin->data.getPtr();
            const Nif::NodeList &bones = skin->bones;
            for(size_t b = 0;b < bones.length();b++)
            {
                Ogre::Bone *bone = skel->getBone(bones[b]->name);
                Ogre::Matrix4 mat;
                mat.makeTransform(data->bones[b].trafo.trans, Ogre::Vector3(data->bones[b].trafo.scale),
                                  Ogre::Quaternion(data->bones[b].trafo.rotation));
                mat = bone->_getFullTransform() * mat;

                const std::vector<Nif::NiSkinData::VertWeight> &weights = data->bones[b].weights;
                for(size_t i = 0;i < weights.size();i++)
                {
                    size_t index = weights[i].vertex;
                    float weight = weights[i].weight;

                    newVerts.at(index) += (mat*srcVerts[index]) * weight;
                    if(newNorms.size() > index)
                    {
                        Ogre::Vector4 vec4(srcNorms[index][0], srcNorms[index][1], srcNorms[index][2], 0.0f);
                        vec4 = mat*vec4 * weight;
                        newNorms[index] += Ogre::Vector3(&vec4[0]);
                    }
                }
            }

            srcVerts = newVerts;
            srcNorms = newNorms;
        }
        else
        {
            Ogre::SkeletonManager *skelMgr = Ogre::SkeletonManager::getSingletonPtr();
            if(skelMgr->getByName(mName).isNull())
            {
                // No skinning and no skeleton, so just transform the vertices and
                // normals into position.
                Ogre::Matrix4 mat4 = shape->getWorldTransform();
                for(size_t i = 0;i < srcVerts.size();i++)
                {
                    Ogre::Vector4 vec4(srcVerts[i].x, srcVerts[i].y, srcVerts[i].z, 1.0f);
                    vec4 = mat4*vec4;
                    srcVerts[i] = Ogre::Vector3(&vec4[0]);
                }
                for(size_t i = 0;i < srcNorms.size();i++)
                {
                    Ogre::Vector4 vec4(srcNorms[i].x, srcNorms[i].y, srcNorms[i].z, 0.0f);
                    vec4 = mat4*vec4;
                    srcNorms[i] = Ogre::Vector3(&vec4[0]);
                }
            }
        }

        // Set the bounding box first
        BoundsFinder bounds;
        bounds.add(&srcVerts[0][0], srcVerts.size());
        if(!bounds.isValid())
        {
            float v[3] = { 0.0f, 0.0f, 0.0f };
            bounds.add(&v[0], 1);
        }

        mesh->_setBounds(Ogre::AxisAlignedBox(bounds.minX()-0.5f, bounds.minY()-0.5f, bounds.minZ()-0.5f,
                                              bounds.maxX()+0.5f, bounds.maxY()+0.5f, bounds.maxZ()+0.5f));
        mesh->_setBoundingSphereRadius(bounds.getRadius());

        // This function is just one long stream of Ogre-barf, but it works
        // great.
        Ogre::HardwareBufferManager *hwBufMgr = Ogre::HardwareBufferManager::getSingletonPtr();
        Ogre::HardwareVertexBufferSharedPtr vbuf;
        Ogre::HardwareIndexBufferSharedPtr ibuf;
        Ogre::VertexBufferBinding *bind;
        Ogre::VertexDeclaration *decl;
        int nextBuf = 0;

        Ogre::SubMesh *sub = mesh->createSubMesh();

        // Add vertices
        sub->useSharedVertices = false;
        sub->vertexData = new Ogre::VertexData();
        sub->vertexData->vertexStart = 0;
        sub->vertexData->vertexCount = srcVerts.size();

        decl = sub->vertexData->vertexDeclaration;
        bind = sub->vertexData->vertexBufferBinding;
        if(srcVerts.size())
        {
            vbuf = hwBufMgr->createVertexBuffer(Ogre::VertexElement::getTypeSize(Ogre::VET_FLOAT3),
                                                srcVerts.size(), vertUsage, vertShadowBuffer);
            vbuf->writeData(0, vbuf->getSizeInBytes(), &srcVerts[0][0], true);

            decl->addElement(nextBuf, 0, Ogre::VET_FLOAT3, Ogre::VES_POSITION);
            bind->setBinding(nextBuf++, vbuf);
        }

        // Vertex normals
        if(srcNorms.size())
        {
            vbuf = hwBufMgr->createVertexBuffer(Ogre::VertexElement::getTypeSize(Ogre::VET_FLOAT3),
                                                srcNorms.size(), vertUsage, vertShadowBuffer);
            vbuf->writeData(0, vbuf->getSizeInBytes(), &srcNorms[0][0], true);

            decl->addElement(nextBuf, 0, Ogre::VET_FLOAT3, Ogre::VES_NORMAL);
            bind->setBinding(nextBuf++, vbuf);
        }

        // Vertex colors
        const std::vector<Ogre::Vector4> &colors = data->colors;
        if(colors.size())
        {
            Ogre::RenderSystem* rs = Ogre::Root::getSingleton().getRenderSystem();
            std::vector<Ogre::RGBA> colorsRGB(colors.size());
            for(size_t i = 0;i < colorsRGB.size();i++)
            {
                Ogre::ColourValue clr(colors[i][0], colors[i][1], colors[i][2], colors[i][3]);
                rs->convertColourValue(clr, &colorsRGB[i]);
            }
            vbuf = hwBufMgr->createVertexBuffer(Ogre::VertexElement::getTypeSize(Ogre::VET_COLOUR),
                                                colorsRGB.size(), Ogre::HardwareBuffer::HBU_STATIC);
            vbuf->writeData(0, vbuf->getSizeInBytes(), &colorsRGB[0], true);
            decl->addElement(nextBuf, 0, Ogre::VET_COLOUR, Ogre::VES_DIFFUSE);
            bind->setBinding(nextBuf++, vbuf);
        }

        // Texture UV coordinates
        size_t numUVs = data->uvlist.size();
        for(size_t i = 0;i < numUVs;i++)
        {
            vbuf = hwBufMgr->createVertexBuffer(Ogre::VertexElement::getTypeSize(Ogre::VET_FLOAT2),
                                                srcVerts.size(), Ogre::HardwareBuffer::HBU_STATIC);
            vbuf->writeData(0, vbuf->getSizeInBytes(), &data->uvlist[i][0], true);

            decl->addElement(nextBuf, 0, Ogre::VET_FLOAT2, Ogre::VES_TEXTURE_COORDINATES, i);
            bind->setBinding(nextBuf++, vbuf);
        }

        // Triangle faces
        const std::vector<short> &srcIdx = data->triangles;
        if(srcIdx.size())
        {
            ibuf = hwBufMgr->createIndexBuffer(Ogre::HardwareIndexBuffer::IT_16BIT, srcIdx.size(),
                                               Ogre::HardwareBuffer::HBU_STATIC);
            ibuf->writeData(0, ibuf->getSizeInBytes(), &srcIdx[0], true);
            sub->indexData->indexBuffer = ibuf;
            sub->indexData->indexCount = srcIdx.size();
            sub->indexData->indexStart = 0;
        }

        // Assign bone weights for this TriShape
        if(skin != NULL)
        {
            const Nif::NiSkinData *data = skin->data.getPtr();
            const Nif::NodeList &bones = skin->bones;
            for(size_t i = 0;i < bones.length();i++)
            {
                Ogre::VertexBoneAssignment boneInf;
                boneInf.boneIndex = skel->getBone(bones[i]->name)->getHandle();

                const std::vector<Nif::NiSkinData::VertWeight> &weights = data->bones[i].weights;
                for(size_t j = 0;j < weights.size();j++)
                {
                    boneInf.vertexIndex = weights[j].vertex;
                    boneInf.weight = weights[j].weight;
                    sub->addBoneAssignment(boneInf);
                }
            }
        }

        const Nif::NiTexturingProperty *texprop = NULL;
        const Nif::NiMaterialProperty *matprop = NULL;
        const Nif::NiAlphaProperty *alphaprop = NULL;
        const Nif::NiVertexColorProperty *vertprop = NULL;
        const Nif::NiZBufferProperty *zprop = NULL;
        const Nif::NiSpecularProperty *specprop = NULL;
        const Nif::NiWireframeProperty *wireprop = NULL;
        bool needTangents = false;

        getNodeProperties(shape, texprop, matprop, alphaprop, vertprop, zprop, specprop, wireprop);
        std::string matname = NIFMaterialLoader::getMaterial(data, mesh->getName(), mGroup,
                                                             texprop, matprop, alphaprop,
                                                             vertprop, zprop, specprop,
                                                             wireprop, needTangents);
        if(matname.length() > 0)
            sub->setMaterialName(matname);

        // build tangents if the material needs them
        if (needTangents)
        {
            unsigned short src,dest;
            if (!mesh->suggestTangentVectorBuildParams(Ogre::VES_TANGENT, src,dest))
                mesh->buildTangentVectors(Ogre::VES_TANGENT, src,dest);
        }
    }


    typedef std::map<std::string,NIFObjectLoader> LoaderMap;
    static LoaderMap sLoaders;


    static void createParticleEmitterAffectors(Ogre::ParticleSystem *partsys, const Nif::NiParticleSystemController *partctrl)
    {
        Ogre::ParticleEmitter *emitter = partsys->addEmitter("Point");
        emitter->setDirection(Ogre::Vector3(0.0f, 0.0f, std::cos(partctrl->verticalDir)));
        emitter->setAngle(Ogre::Radian(partctrl->verticalAngle));
        emitter->setParticleVelocity(partctrl->velocity-partctrl->velocityRandom,
                                     partctrl->velocity+partctrl->velocityRandom);
        emitter->setEmissionRate(partctrl->emitRate);
        emitter->setTimeToLive(partctrl->lifetime-partctrl->lifetimeRandom,
                               partctrl->lifetime+partctrl->lifetimeRandom);

        Nif::ExtraPtr e = partctrl->extra;
        while(!e.empty())
        {
            if(e->recType == Nif::RC_NiParticleGrowFade)
            {
                const Nif::NiParticleGrowFade *gf = static_cast<const Nif::NiParticleGrowFade*>(e.getPtr());
                Ogre::ParticleAffector *affector = partsys->addAffector("GrowFade");
                affector->setParameter("grow_time", Ogre::StringConverter::toString(gf->growTime));
                affector->setParameter("fade_time", Ogre::StringConverter::toString(gf->fadeTime));
            }
            else if(e->recType == Nif::RC_NiParticleRotation)
            {
                // TODO: Implement (Ogre::RotationAffector?)
            }
            else if(e->recType == Nif::RC_NiParticleColorModifier)
            {
                // TODO: Implement (Ogre::ColourInterpolatorAffector?)
            }
            else if(e->recType == Nif::RC_NiGravity)
            {
                // TODO: Implement
            }
            else
                warn("Unhandled particle modifier "+e->recName);
            e = e->extra;
        }
    }

    Ogre::ParticleSystem *createParticleSystem(Ogre::SceneManager *sceneMgr, Ogre::Entity *entitybase,
                                               const Nif::Node *partnode)
    {
        const Nif::NiAutoNormalParticlesData *particledata = NULL;
        if(partnode->recType == Nif::RC_NiAutoNormalParticles)
            particledata = static_cast<const Nif::NiAutoNormalParticles*>(partnode)->data.getPtr();
        else if(partnode->recType == Nif::RC_NiRotatingParticles)
            particledata = static_cast<const Nif::NiRotatingParticles*>(partnode)->data.getPtr();

        Ogre::ParticleSystem *partsys = sceneMgr->createParticleSystem();
        try {
            std::string fullname = mName+"@index="+Ogre::StringConverter::toString(partnode->recIndex);
            if(partnode->name.length() > 0)
                fullname += "@type="+partnode->name;
            Misc::StringUtils::toLower(fullname);

            const Nif::NiTexturingProperty *texprop = NULL;
            const Nif::NiMaterialProperty *matprop = NULL;
            const Nif::NiAlphaProperty *alphaprop = NULL;
            const Nif::NiVertexColorProperty *vertprop = NULL;
            const Nif::NiZBufferProperty *zprop = NULL;
            const Nif::NiSpecularProperty *specprop = NULL;
            const Nif::NiWireframeProperty *wireprop = NULL;
            bool needTangents = false;

            getNodeProperties(partnode, texprop, matprop, alphaprop, vertprop, zprop, specprop, wireprop);
            partsys->setMaterialName(NIFMaterialLoader::getMaterial(particledata, fullname, mGroup,
                                                                    texprop, matprop, alphaprop,
                                                                    vertprop, zprop, specprop,
                                                                    wireprop, needTangents));

            partsys->setDefaultDimensions(particledata->particleRadius*2.0f,
                                          particledata->particleRadius*2.0f);
            partsys->setCullIndividually(false);
            partsys->setParticleQuota(particledata->numParticles);

            Nif::ControllerPtr ctrl = partnode->controller;
            while(!ctrl.empty())
            {
                if(ctrl->recType == Nif::RC_NiParticleSystemController)
                {
                    const Nif::NiParticleSystemController *partctrl = static_cast<const Nif::NiParticleSystemController*>(ctrl.getPtr());

                    createParticleEmitterAffectors(partsys, partctrl);
                    if(!partctrl->emitter.empty() && !partsys->isAttached())
                    {
                        int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, partctrl->emitter->recIndex);
                        Ogre::Bone *trgtbone = entitybase->getSkeleton()->getBone(trgtid);
                        entitybase->attachObjectToBone(trgtbone->getName(), partsys);
                    }
                }
                ctrl = ctrl->next;
            }

            if(!partsys->isAttached())
            {
                int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, partnode->recIndex);
                Ogre::Bone *trgtbone = entitybase->getSkeleton()->getBone(trgtid);
                entitybase->attachObjectToBone(trgtbone->getName(), partsys);
            }
        }
        catch(std::exception &e) {
            std::cerr<< "Particles exception: "<<e.what() <<std::endl;
            sceneMgr->destroyParticleSystem(partsys);
            partsys = NULL;
        };
        return partsys;
    }


    NIFObjectLoader(const std::string &name, const std::string &group)
      : mName(name), mGroup(group), mShapeIndex(~(size_t)0)
    { }

    virtual void loadResource(Ogre::Resource *resource)
    {
        Ogre::Mesh *mesh = dynamic_cast<Ogre::Mesh*>(resource);
        OgreAssert(mesh, "Attempting to load a mesh into a non-mesh resource!");

        Nif::NIFFile::ptr nif = Nif::NIFFile::create(mName);
        if(mShapeIndex >= nif->numRecords())
        {
            Ogre::SkeletonManager *skelMgr = Ogre::SkeletonManager::getSingletonPtr();
            if(!skelMgr->getByName(mName).isNull())
                mesh->setSkeletonName(mName);
            return;
        }

        const Nif::Record *record = nif->getRecord(mShapeIndex);
        createSubMesh(mesh, dynamic_cast<const Nif::NiTriShape*>(record));
    }

    void createObjects(Ogre::SceneManager *sceneMgr, const Nif::Node *node, ObjectList &objectlist, int flags=0)
    {
        // Do not create objects for the collision shape (includes all children)
        if(node->recType == Nif::RC_RootCollisionNode)
            return;

        // Marker objects: just skip the entire node branch
        /// \todo don't do this in the editor
        if (node->name.find("marker") != std::string::npos)
            return;

        flags |= node->flags;

        Nif::ExtraPtr e = node->extra;
        while(!e.empty())
        {
            if(e->recType == Nif::RC_NiStringExtraData)
            {
                const Nif::NiStringExtraData *sd = static_cast<const Nif::NiStringExtraData*>(e.getPtr());
                // String markers may contain important information
                // affecting the entire subtree of this obj
                if(sd->string == "MRK")
                {
                    // Marker objects. These meshes are only visible in the
                    // editor.
                    flags |= 0x80000000;
                }
            }
            e = e->extra;
        }

        if(node->recType == Nif::RC_NiCamera)
        {
            int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, node->recIndex);
            Ogre::Bone *trgtbone = objectlist.mSkelBase->getSkeleton()->getBone(trgtid);
            objectlist.mCameras.push_back(trgtbone);
        }

        Nif::ControllerPtr ctrl = node->controller;
        while(!ctrl.empty())
        {
            if(ctrl->recType == Nif::RC_NiVisController)
            {
                const Nif::NiVisController *vis = static_cast<const Nif::NiVisController*>(ctrl.getPtr());

                int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, ctrl->target->recIndex);
                Ogre::Bone *trgtbone = objectlist.mSkelBase->getSkeleton()->getBone(trgtid);
                Ogre::ControllerValueRealPtr srcval; /* Filled in later */
                Ogre::ControllerValueRealPtr dstval(OGRE_NEW VisController::Value(trgtbone, vis->data.getPtr()));
                Ogre::ControllerFunctionRealPtr func(OGRE_NEW VisController::Function(vis, false));

                objectlist.mControllers.push_back(Ogre::Controller<Ogre::Real>(srcval, dstval, func));
            }
            else if(ctrl->recType == Nif::RC_NiKeyframeController)
            {
                const Nif::NiKeyframeController *key = static_cast<const Nif::NiKeyframeController*>(ctrl.getPtr());
                if(!key->data.empty())
                {
                    int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, ctrl->target->recIndex);
                    Ogre::Bone *trgtbone = objectlist.mSkelBase->getSkeleton()->getBone(trgtid);
                    Ogre::ControllerValueRealPtr srcval; /* Filled in later */
                    Ogre::ControllerValueRealPtr dstval(OGRE_NEW KeyframeController::Value(trgtbone, key->data.getPtr()));
                    Ogre::ControllerFunctionRealPtr func(OGRE_NEW KeyframeController::Function(key, false));

                    objectlist.mControllers.push_back(Ogre::Controller<Ogre::Real>(srcval, dstval, func));
                }
            }
            ctrl = ctrl->next;
        }

        if(node->recType == Nif::RC_NiTriShape && !(flags&0x80000000))
        {
            const Nif::NiTriShape *shape = static_cast<const Nif::NiTriShape*>(node);

            Ogre::MeshManager &meshMgr = Ogre::MeshManager::getSingleton();
            std::string fullname = mName+"@index="+Ogre::StringConverter::toString(shape->recIndex);
            if(shape->name.length() > 0)
                fullname += "@shape="+shape->name;

            Misc::StringUtils::toLower(fullname);
            Ogre::MeshPtr mesh = meshMgr.getByName(fullname);
            if(mesh.isNull())
            {
                NIFObjectLoader *loader = &sLoaders[fullname];
                *loader = *this;
                loader->mShapeIndex = shape->recIndex;

                mesh = meshMgr.createManual(fullname, mGroup, loader);
                mesh->setAutoBuildEdgeLists(false);
            }

            Ogre::Entity *entity = sceneMgr->createEntity(mesh);
            entity->setVisible(!(flags&0x01));

            objectlist.mEntities.push_back(entity);
            if(objectlist.mSkelBase)
            {
                if(entity->hasSkeleton())
                    entity->shareSkeletonInstanceWith(objectlist.mSkelBase);
                else
                {
                    int trgtid = NIFSkeletonLoader::lookupOgreBoneHandle(mName, shape->recIndex);
                    Ogre::Bone *trgtbone = objectlist.mSkelBase->getSkeleton()->getBone(trgtid);
                    objectlist.mSkelBase->attachObjectToBone(trgtbone->getName(), entity);
                }
            }

            Nif::ControllerPtr ctrl = node->controller;
            while(!ctrl.empty())
            {
                if(ctrl->recType == Nif::RC_NiUVController)
                {
                    const Nif::NiUVController *uv = static_cast<const Nif::NiUVController*>(ctrl.getPtr());

                    const Ogre::MaterialPtr &material = entity->getSubEntity(0)->getMaterial();
                    Ogre::ControllerValueRealPtr srcval(Ogre::ControllerManager::getSingleton().getFrameTimeSource());
                    Ogre::ControllerValueRealPtr dstval(OGRE_NEW UVController::Value(material, uv->data.getPtr()));
                    Ogre::ControllerFunctionRealPtr func(OGRE_NEW UVController::Function(uv, true));

                    objectlist.mControllers.push_back(Ogre::Controller<Ogre::Real>(srcval, dstval, func));
                }
                ctrl = ctrl->next;
            }
        }

        if(node->recType == Nif::RC_NiAutoNormalParticles ||
           node->recType == Nif::RC_NiRotatingParticles)
        {
            Ogre::ParticleSystem *partsys = createParticleSystem(sceneMgr, objectlist.mSkelBase, node);
            if(partsys != NULL)
            {
                partsys->setVisible(!(flags&0x01));
                objectlist.mParticles.push_back(partsys);
            }
        }

        const Nif::NiNode *ninode = dynamic_cast<const Nif::NiNode*>(node);
        if(ninode)
        {
            const Nif::NodeList &children = ninode->children;
            for(size_t i = 0;i < children.length();i++)
            {
                if(!children[i].empty())
                    createObjects(sceneMgr, children[i].getPtr(), objectlist, flags);
            }
        }
    }

    void createSkelBase(Ogre::SceneManager *sceneMgr, const Nif::Node *node, ObjectList &objectlist)
    {
        /* This creates an empty mesh to which a skeleton gets attached. This
         * is to ensure we have an entity with a skeleton instance, even if all
         * other meshes are hidden or entities attached to a specific node
         * instead of skinned. */
        std::string fullname = mName;
        Misc::StringUtils::toLower(fullname);

        Ogre::MeshManager &meshMgr = Ogre::MeshManager::getSingleton();
        Ogre::MeshPtr mesh = meshMgr.getByName(fullname);
        if(mesh.isNull())
        {
            NIFObjectLoader *loader = &sLoaders[fullname];
            *loader = *this;

            mesh = meshMgr.createManual(fullname, mGroup, loader);
            mesh->setAutoBuildEdgeLists(false);
        }
        objectlist.mSkelBase = sceneMgr->createEntity(mesh);
        objectlist.mEntities.push_back(objectlist.mSkelBase);
    }

public:
    NIFObjectLoader() : mShapeIndex(~(size_t)0)
    { }

    static void load(Ogre::SceneManager *sceneMgr, ObjectList &objectlist, const std::string &name, const std::string &group)
    {
        Nif::NIFFile::ptr pnif = Nif::NIFFile::create(name);
        Nif::NIFFile &nif = *pnif.get();
        if(nif.numRoots() < 1)
        {
            nif.warn("Found no root nodes in "+name+".");
            return;
        }

        // The first record is assumed to be the root node
        const Nif::Record *r = nif.getRoot(0);
        assert(r != NULL);

        const Nif::Node *node = dynamic_cast<Nif::Node const *>(r);
        if(node == NULL)
        {
            nif.warn("First root in "+name+" was not a node, but a "+
                     r->recName+".");
            return;
        }

        bool hasSkel = Ogre::SkeletonManager::getSingleton().resourceExists(name);
        if(!hasSkel)
            hasSkel = !NIFSkeletonLoader::createSkeleton(name, group, node).isNull();

        NIFObjectLoader meshldr(name, group);
        if(hasSkel)
            meshldr.createSkelBase(sceneMgr, node, objectlist);
        meshldr.createObjects(sceneMgr, node, objectlist);
    }
};
NIFObjectLoader::LoaderMap NIFObjectLoader::sLoaders;


ObjectList Loader::createObjects(Ogre::SceneNode *parentNode, std::string name, const std::string &group)
{
    ObjectList objectlist;

    Misc::StringUtils::toLower(name);
    NIFObjectLoader::load(parentNode->getCreator(), objectlist, name, group);

    for(size_t i = 0;i < objectlist.mEntities.size();i++)
    {
        Ogre::Entity *entity = objectlist.mEntities[i];
        if(!entity->isAttached())
            parentNode->attachObject(entity);
    }

    return objectlist;
}

ObjectList Loader::createObjects(Ogre::Entity *parent, const std::string &bonename,
                                 Ogre::SceneNode *parentNode,
                                 std::string name, const std::string &group)
{
    ObjectList objectlist;

    Misc::StringUtils::toLower(name);
    NIFObjectLoader::load(parentNode->getCreator(), objectlist, name, group);

    bool isskinned = false;
    for(size_t i = 0;i < objectlist.mEntities.size();i++)
    {
        Ogre::Entity *ent = objectlist.mEntities[i];
        if(objectlist.mSkelBase != ent && ent->hasSkeleton())
        {
            isskinned = true;
            break;
        }
    }

    Ogre::Vector3 scale(1.0f);
    if(bonename.find("Left") != std::string::npos)
        scale.x *= -1.0f;

    if(isskinned)
    {
        std::string filter = "@shape=tri "+bonename;
        Misc::StringUtils::toLower(filter);
        for(size_t i = 0;i < objectlist.mEntities.size();i++)
        {
            Ogre::Entity *entity = objectlist.mEntities[i];
            if(entity->hasSkeleton())
            {
                if(entity == objectlist.mSkelBase ||
                   entity->getMesh()->getName().find(filter) != std::string::npos)
                    parentNode->attachObject(entity);
            }
            else
            {
                if(entity->getMesh()->getName().find(filter) == std::string::npos)
                    entity->detachFromParent();
            }
        }
    }
    else
    {
        for(size_t i = 0;i < objectlist.mEntities.size();i++)
        {
            Ogre::Entity *entity = objectlist.mEntities[i];
            if(!entity->isAttached())
            {
                Ogre::TagPoint *tag = parent->attachObjectToBone(bonename, entity);
                tag->setScale(scale);
            }
        }
    }

    return objectlist;
}


ObjectList Loader::createObjectBase(Ogre::SceneManager *sceneMgr, std::string name, const std::string &group)
{
    ObjectList objectlist;

    Misc::StringUtils::toLower(name);
    NIFObjectLoader::load(sceneMgr, objectlist, name, group);

    return objectlist;
}

} // namespace NifOgre