/*
---------------------------------------------------------------------------
Open Asset Import Library (assimp)
---------------------------------------------------------------------------

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All rights reserved.

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  copyright notice, this list of conditions and the
  following disclaimer.

* Redistributions in binary form must reproduce the above
  copyright notice, this list of conditions and the
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  derived from this software without specific prior
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*/

/** @file  SMDLoader.cpp 
 *  @brief Implementation of the SMD importer class 
 */


#ifndef ASSIMP_BUILD_NO_SMD_IMPORTER

// internal headers
#include "SMDLoader.h"
#include "fast_atof.h"
#include "SkeletonMeshBuilder.h"
#include "../include/assimp/Importer.hpp"
#include "../include/assimp/IOSystem.hpp"
#include <boost/scoped_ptr.hpp>
#include "../include/assimp/scene.h"
#include "../include/assimp/DefaultLogger.hpp"


using namespace Assimp;

static const aiImporterDesc desc = {
	"Valve SMD Importer",
	"",
	"",
	"",
	aiImporterFlags_SupportTextFlavour,
	0,
	0,
	0,
	0,
	"smd vta" 
};

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
SMDImporter::SMDImporter()
{}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
SMDImporter::~SMDImporter()
{}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool SMDImporter::CanRead( const std::string& pFile, IOSystem* /*pIOHandler*/, bool) const
{
	// fixme: auto format detection
	return SimpleExtensionCheck(pFile,"smd","vta");
}

// ------------------------------------------------------------------------------------------------
// Get a list of all supported file extensions
const aiImporterDesc* SMDImporter::GetInfo () const
{
	return &desc;
}

// ------------------------------------------------------------------------------------------------
// Setup configuration properties
void SMDImporter::SetupProperties(const Importer* pImp)
{
	// The 
	// AI_CONFIG_IMPORT_SMD_KEYFRAME option overrides the
	// AI_CONFIG_IMPORT_GLOBAL_KEYFRAME option.
	configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_SMD_KEYFRAME,-1);
	if(static_cast<unsigned int>(-1) == configFrameID)	{
		configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_GLOBAL_KEYFRAME,0);
	}
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void SMDImporter::InternReadFile( const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler)
{
	boost::scoped_ptr<IOStream> file( pIOHandler->Open( pFile, "rb"));

	// Check whether we can read from the file
	if( file.get() == NULL)	{
		throw DeadlyImportError( "Failed to open SMD/VTA file " + pFile + ".");
	}

	iFileSize = (unsigned int)file->FileSize();

	// Allocate storage and copy the contents of the file to a memory buffer
	this->pScene = pScene;

	std::vector<char> buff(iFileSize+1);
	TextFileToBuffer(file.get(),buff);
	mBuffer = &buff[0];

	iSmallestFrame = (1 << 31);
	bHasUVs = true;
	iLineNumber = 1;

	// Reserve enough space for ... hm ... 10 textures
	aszTextures.reserve(10);

	// Reserve enough space for ... hm ... 1000 triangles
	asTriangles.reserve(1000);

	// Reserve enough space for ... hm ... 20 bones
	asBones.reserve(20);


	// parse the file ...
	ParseFile();

	// If there are no triangles it seems to be an animation SMD,
	// containing only the animation skeleton.
	if (asTriangles.empty())
	{
		if (asBones.empty())
		{
			throw DeadlyImportError("SMD: No triangles and no bones have "
				"been found in the file. This file seems to be invalid.");
		}

		// Set the flag in the scene structure which indicates
		// that there is nothing than an animation skeleton
		pScene->mFlags |= AI_SCENE_FLAGS_INCOMPLETE;
	}

	if (!asBones.empty())
	{
		// Check whether all bones have been initialized
		for (std::vector<SMD::Bone>::const_iterator
			i =  asBones.begin();
			i != asBones.end();++i)
		{
			if (!(*i).mName.length())
			{
				DefaultLogger::get()->warn("SMD: Not all bones have been initialized");
				break;
			}
		}

		// now fix invalid time values and make sure the animation starts at frame 0
		FixTimeValues();

		// compute absolute bone transformation matrices
	//	ComputeAbsoluteBoneTransformations();
	}

	if (!(pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))
	{
		// create output meshes
		CreateOutputMeshes();

		// build an output material list
		CreateOutputMaterials();
	}

	// build the output animation
	CreateOutputAnimations();

	// build output nodes (bones are added as empty dummy nodes)
	CreateOutputNodes();

	if (pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE)
	{
		SkeletonMeshBuilder skeleton(pScene);
	}
}
// ------------------------------------------------------------------------------------------------
// Write an error message with line number to the log file
void SMDImporter::LogErrorNoThrow(const char* msg)
{
	char szTemp[1024];
	sprintf(szTemp,"Line %u: %s",iLineNumber,msg);
	DefaultLogger::get()->error(szTemp);
}

// ------------------------------------------------------------------------------------------------
// Write a warning with line number to the log file
void SMDImporter::LogWarning(const char* msg)
{
	char szTemp[1024];
	ai_assert(strlen(msg) < 1000);
	sprintf(szTemp,"Line %u: %s",iLineNumber,msg);
	DefaultLogger::get()->warn(szTemp);
}

// ------------------------------------------------------------------------------------------------
// Fix invalid time values in the file
void SMDImporter::FixTimeValues()
{
	double dDelta = (double)iSmallestFrame;
	double dMax = 0.0f;
	for (std::vector<SMD::Bone>::iterator
		iBone =  asBones.begin();
		iBone != asBones.end();++iBone)
	{
		for (std::vector<SMD::Bone::Animation::MatrixKey>::iterator
			iKey =  (*iBone).sAnim.asKeys.begin();
			iKey != (*iBone).sAnim.asKeys.end();++iKey)
		{
			(*iKey).dTime -= dDelta;
			dMax = std::max(dMax, (*iKey).dTime);
		}
	}
	dLengthOfAnim = dMax;
}

// ------------------------------------------------------------------------------------------------
// create output meshes
void SMDImporter::CreateOutputMeshes()
{
	if (aszTextures.empty())
		aszTextures.push_back(std::string());

	// we need to sort all faces by their material index
	// in opposition to other loaders we can be sure that each
	// material is at least used once.
	pScene->mNumMeshes = (unsigned int) aszTextures.size();
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];

	typedef std::vector<unsigned int> FaceList;
	FaceList* aaiFaces = new FaceList[pScene->mNumMeshes];

	// approximate the space that will be required
	unsigned int iNum = (unsigned int)asTriangles.size() / pScene->mNumMeshes;
	iNum += iNum >> 1;
	for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
		aaiFaces[i].reserve(iNum);


	// collect all faces
	iNum = 0;
	for (std::vector<SMD::Face>::const_iterator
		iFace =  asTriangles.begin();
		iFace != asTriangles.end();++iFace,++iNum)
	{
		if (UINT_MAX == (*iFace).iTexture)aaiFaces[(*iFace).iTexture].push_back( 0 );
		else if ((*iFace).iTexture >= aszTextures.size())
		{
			DefaultLogger::get()->error("[SMD/VTA] Material index overflow in face");
			aaiFaces[(*iFace).iTexture].push_back((unsigned int)aszTextures.size()-1);
		}
		else aaiFaces[(*iFace).iTexture].push_back(iNum);
	} 

	// now create the output meshes
	for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
	{
		aiMesh*& pcMesh = pScene->mMeshes[i] = new aiMesh();
		ai_assert(!aaiFaces[i].empty()); // should not be empty ...

		pcMesh->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;
		pcMesh->mNumVertices = (unsigned int)aaiFaces[i].size()*3;
		pcMesh->mNumFaces = (unsigned int)aaiFaces[i].size();
		pcMesh->mMaterialIndex = i;

		// storage for bones
		typedef std::pair<unsigned int,float> TempWeightListEntry;
		typedef std::vector< TempWeightListEntry > TempBoneWeightList;

		TempBoneWeightList* aaiBones = new TempBoneWeightList[asBones.size()]();

		// try to reserve enough memory without wasting too much
		for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
		{
			aaiBones[iBone].reserve(pcMesh->mNumVertices/asBones.size());
		}

		// allocate storage
		pcMesh->mFaces = new aiFace[pcMesh->mNumFaces];
		aiVector3D* pcNormals = pcMesh->mNormals = new aiVector3D[pcMesh->mNumVertices];
		aiVector3D* pcVerts = pcMesh->mVertices = new aiVector3D[pcMesh->mNumVertices];

		aiVector3D* pcUVs = NULL;
		if (bHasUVs)
		{
			pcUVs = pcMesh->mTextureCoords[0] = new aiVector3D[pcMesh->mNumVertices];
			pcMesh->mNumUVComponents[0] = 2;
		}

		iNum = 0;
		for (unsigned int iFace = 0; iFace < pcMesh->mNumFaces;++iFace)
		{
			pcMesh->mFaces[iFace].mIndices = new unsigned int[3];
			pcMesh->mFaces[iFace].mNumIndices = 3;

			// fill the vertices 
			unsigned int iSrcFace = aaiFaces[i][iFace];
			SMD::Face& face = asTriangles[iSrcFace];

			*pcVerts++ = face.avVertices[0].pos;
			*pcVerts++ = face.avVertices[1].pos;
			*pcVerts++ = face.avVertices[2].pos; 

			// fill the normals
			*pcNormals++ = face.avVertices[0].nor;
			*pcNormals++ = face.avVertices[1].nor;
			*pcNormals++ = face.avVertices[2].nor;

			// fill the texture coordinates
			if (pcUVs)
			{
				*pcUVs++ = face.avVertices[0].uv;
				*pcUVs++ = face.avVertices[1].uv;
				*pcUVs++ = face.avVertices[2].uv;
			}
			
			for (unsigned int iVert = 0; iVert < 3;++iVert)
			{
				float fSum = 0.0f;
				for (unsigned int iBone = 0;iBone < face.avVertices[iVert].aiBoneLinks.size();++iBone)
				{
					TempWeightListEntry& pairval = face.avVertices[iVert].aiBoneLinks[iBone];

					// FIX: The second check is here just to make sure we won't 
					// assign more than one weight to a single vertex index
					if (pairval.first >= asBones.size() || 
						pairval.first == face.avVertices[iVert].iParentNode)
					{
						DefaultLogger::get()->error("[SMD/VTA] Bone index overflow. "
							"The bone index will be ignored, the weight will be assigned "
							"to the vertex' parent node");
						continue;
					}
					aaiBones[pairval.first].push_back(TempWeightListEntry(iNum,pairval.second));
					fSum += pairval.second;
				}
				// ******************************************************************
				// If the sum of all vertex weights is not 1.0 we must assign 
				// the rest to the vertex' parent node. Well, at least the doc says 
				// we should ...
				// FIX: We use 0.975 as limit, floating-point inaccuracies seem to
				// be very strong in some SMD exporters. Furthermore it is possible
				// that the parent of a vertex is 0xffffffff (if the corresponding
				// entry in the file was unreadable)
				// ******************************************************************
				if (fSum < 0.975f && face.avVertices[iVert].iParentNode != UINT_MAX)
				{
					if (face.avVertices[iVert].iParentNode >= asBones.size())
					{
						DefaultLogger::get()->error("[SMD/VTA] Bone index overflow. "
							"The index of the vertex parent bone is invalid. "
							"The remaining weights will be normalized to 1.0");

						if (fSum)
						{
							fSum = 1 / fSum;
							for (unsigned int iBone = 0;iBone < face.avVertices[iVert].aiBoneLinks.size();++iBone)
							{
								TempWeightListEntry& pairval = face.avVertices[iVert].aiBoneLinks[iBone];
								if (pairval.first >= asBones.size())continue;
								aaiBones[pairval.first].back().second *= fSum;
							}
						}
					}
					else
					{
						aaiBones[face.avVertices[iVert].iParentNode].push_back(
							TempWeightListEntry(iNum,1.0f-fSum));
					}
				}
				pcMesh->mFaces[iFace].mIndices[iVert] = iNum++;
			}
		}

		// now build all bones of the mesh
		iNum = 0;
		for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
			if (!aaiBones[iBone].empty())++iNum;
		
		if (false && iNum)
		{
			pcMesh->mNumBones = iNum;
			pcMesh->mBones = new aiBone*[pcMesh->mNumBones];
			iNum = 0;
			for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
			{
				if (aaiBones[iBone].empty())continue;
				aiBone*& bone = pcMesh->mBones[iNum] = new aiBone();

				bone->mNumWeights = (unsigned int)aaiBones[iBone].size();
				bone->mWeights = new aiVertexWeight[bone->mNumWeights];
				bone->mOffsetMatrix = asBones[iBone].mOffsetMatrix;
				bone->mName.Set( asBones[iBone].mName );

				asBones[iBone].bIsUsed = true;

				for (unsigned int iWeight = 0; iWeight < bone->mNumWeights;++iWeight)
				{
					bone->mWeights[iWeight].mVertexId = aaiBones[iBone][iWeight].first;
					bone->mWeights[iWeight].mWeight = aaiBones[iBone][iWeight].second;
				}
				++iNum;
			}
		}
		delete[] aaiBones;
	}
	delete[] aaiFaces;
}

// ------------------------------------------------------------------------------------------------
// add bone child nodes
void SMDImporter::AddBoneChildren(aiNode* pcNode, uint32_t iParent)
{
	ai_assert(NULL != pcNode && 0 == pcNode->mNumChildren && NULL == pcNode->mChildren);

	// first count ...
	for (unsigned int i = 0; i < asBones.size();++i)
	{
		SMD::Bone& bone = asBones[i];
		if (bone.iParent == iParent)++pcNode->mNumChildren;
	}

	// now allocate the output array
	pcNode->mChildren = new aiNode*[pcNode->mNumChildren];

	// and fill all subnodes
	unsigned int qq = 0;
	for (unsigned int i = 0; i < asBones.size();++i)
	{
		SMD::Bone& bone = asBones[i];
		if (bone.iParent != iParent)continue;

		aiNode* pc = pcNode->mChildren[qq++] = new aiNode();
		pc->mName.Set(bone.mName);

		// store the local transformation matrix of the bind pose
		pc->mTransformation = bone.sAnim.asKeys[bone.sAnim.iFirstTimeKey].matrix;
		pc->mParent = pcNode;

		// add children to this node, too
		AddBoneChildren(pc,i);
	}
}

// ------------------------------------------------------------------------------------------------
// create output nodes
void SMDImporter::CreateOutputNodes()
{
	pScene->mRootNode = new aiNode();
	if (!(pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))
	{
		// create one root node that renders all meshes
		pScene->mRootNode->mNumMeshes = pScene->mNumMeshes;
		pScene->mRootNode->mMeshes = new unsigned int[pScene->mNumMeshes];
		for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
			pScene->mRootNode->mMeshes[i] = i;
	}

	// now add all bones as dummy sub nodes to the graph
	// AddBoneChildren(pScene->mRootNode,(uint32_t)-1);

	// if we have only one bone we can even remove the root node
	if (pScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE && 
		1 == pScene->mRootNode->mNumChildren)
	{
		aiNode* pcOldRoot = pScene->mRootNode;
		pScene->mRootNode = pcOldRoot->mChildren[0];
		pcOldRoot->mChildren[0] = NULL;
		delete pcOldRoot;

		pScene->mRootNode->mParent = NULL;
	}
	else
	{
		::strcpy(pScene->mRootNode->mName.data, "<SMD_root>");
		pScene->mRootNode->mName.length = 10;
	}
}

// ------------------------------------------------------------------------------------------------
// create output animations
void SMDImporter::CreateOutputAnimations()
{
	unsigned int iNumBones = 0;
	for (std::vector<SMD::Bone>::const_iterator
		i =  asBones.begin();
		i != asBones.end();++i)
	{
		if ((*i).bIsUsed)++iNumBones;
	}
	if (!iNumBones)
	{
		// just make sure this case doesn't occur ... (it could occur
		// if the file was invalid)
		return;
	}

	pScene->mNumAnimations = 1;
	pScene->mAnimations = new aiAnimation*[1];
	aiAnimation*& anim = pScene->mAnimations[0] = new aiAnimation();

	anim->mDuration = dLengthOfAnim;
	anim->mNumChannels = iNumBones;
	anim->mTicksPerSecond = 25.0; // FIXME: is this correct?

	aiNodeAnim** pp = anim->mChannels = new aiNodeAnim*[anim->mNumChannels];
	
	// now build valid keys
	unsigned int a = 0;
	for (std::vector<SMD::Bone>::const_iterator
		i =  asBones.begin();
		i != asBones.end();++i)
	{
		if (!(*i).bIsUsed)continue;

		aiNodeAnim* p = pp[a] = new aiNodeAnim();

		// copy the name of the bone
		p->mNodeName.Set( i->mName);

		p->mNumRotationKeys = (unsigned int) (*i).sAnim.asKeys.size();
		if (p->mNumRotationKeys)
		{
			p->mNumPositionKeys = p->mNumRotationKeys;
			aiVectorKey* pVecKeys = p->mPositionKeys = new aiVectorKey[p->mNumRotationKeys];
			aiQuatKey* pRotKeys = p->mRotationKeys = new aiQuatKey[p->mNumRotationKeys];

			for (std::vector<SMD::Bone::Animation::MatrixKey>::const_iterator
				qq =  (*i).sAnim.asKeys.begin();
				qq != (*i).sAnim.asKeys.end(); ++qq)
			{
				pRotKeys->mTime = pVecKeys->mTime = (*qq).dTime;

				// compute the rotation quaternion from the euler angles
				pRotKeys->mValue = aiQuaternion( (*qq).vRot.x, (*qq).vRot.y, (*qq).vRot.z );
				pVecKeys->mValue = (*qq).vPos;

				++pVecKeys; ++pRotKeys;
			}
		}
		++a;

		// there are no scaling keys ...
	}
}

// ------------------------------------------------------------------------------------------------
void SMDImporter::ComputeAbsoluteBoneTransformations()
{
	// For each bone: determine the key with the lowest time value
	// theoretically the SMD format should have all keyframes
	// in order. However, I've seen a file where this wasn't true.
	for (unsigned int i = 0; i < asBones.size();++i)
	{
		SMD::Bone& bone = asBones[i];

		uint32_t iIndex = 0;
		double dMin = 10e10;
		for (unsigned int i = 0; i < bone.sAnim.asKeys.size();++i)
		{
			double d = std::min(bone.sAnim.asKeys[i].dTime,dMin);
			if (d < dMin)	
			{
				dMin = d;
				iIndex = i;
			}
		}
		bone.sAnim.iFirstTimeKey = iIndex;
	}

	unsigned int iParent = 0;
	while (iParent < asBones.size())
	{
		for (unsigned int iBone = 0; iBone < asBones.size();++iBone)
		{
			SMD::Bone& bone = asBones[iBone];
	
			if (iParent == bone.iParent)
			{
				SMD::Bone& parentBone = asBones[iParent];

			
				uint32_t iIndex = bone.sAnim.iFirstTimeKey;
				const aiMatrix4x4& mat = bone.sAnim.asKeys[iIndex].matrix;
				aiMatrix4x4& matOut = bone.sAnim.asKeys[iIndex].matrixAbsolute;

				// The same for the parent bone ...
				iIndex = parentBone.sAnim.iFirstTimeKey;
				const aiMatrix4x4& mat2 = parentBone.sAnim.asKeys[iIndex].matrixAbsolute;

				// Compute the absolute transformation matrix
				matOut = mat * mat2;
			}
		}
		++iParent;
	}

	// Store the inverse of the absolute transformation matrix 
	// of the first key as bone offset matrix
	for (iParent = 0; iParent < asBones.size();++iParent)
	{
		SMD::Bone& bone = asBones[iParent];
		bone.mOffsetMatrix = bone.sAnim.asKeys[bone.sAnim.iFirstTimeKey].matrixAbsolute;
		bone.mOffsetMatrix.Inverse();
	}
}

// ------------------------------------------------------------------------------------------------
// create output materials
void SMDImporter::CreateOutputMaterials()
{
	pScene->mNumMaterials = (unsigned int)aszTextures.size();
	pScene->mMaterials = new aiMaterial*[std::max(1u, pScene->mNumMaterials)];

	for (unsigned int iMat = 0; iMat < pScene->mNumMaterials;++iMat)
	{
		aiMaterial* pcMat = new aiMaterial();
		pScene->mMaterials[iMat] = pcMat;

		aiString szName;
		szName.length = (size_t)::sprintf(szName.data,"Texture_%u",iMat);
		pcMat->AddProperty(&szName,AI_MATKEY_NAME);

		if (aszTextures[iMat].length())
		{
			::strcpy(szName.data, aszTextures[iMat].c_str() );
			szName.length = aszTextures[iMat].length();
			pcMat->AddProperty(&szName,AI_MATKEY_TEXTURE_DIFFUSE(0));
		}
	}

	// create a default material if necessary
	if (0 == pScene->mNumMaterials)
	{
		pScene->mNumMaterials = 1;

		aiMaterial* pcHelper = new aiMaterial();
		pScene->mMaterials[0] = pcHelper;

		int iMode = (int)aiShadingMode_Gouraud;
		pcHelper->AddProperty<int>(&iMode, 1, AI_MATKEY_SHADING_MODEL);

		aiColor3D clr;
		clr.b = clr.g = clr.r = 0.7f;
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_DIFFUSE);
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_SPECULAR);

		clr.b = clr.g = clr.r = 0.05f;
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_AMBIENT);

		aiString szName;
		szName.Set(AI_DEFAULT_MATERIAL_NAME);
		pcHelper->AddProperty(&szName,AI_MATKEY_NAME);
	}
}

// ------------------------------------------------------------------------------------------------
// Parse the file
void SMDImporter::ParseFile()
{
	const char* szCurrent = mBuffer;

	// read line per line ...
	for ( ;; )
	{
		if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

		// "version <n> \n", <n> should be 1 for hl and hlČ SMD files
		if (TokenMatch(szCurrent,"version",7))
		{
			if(!SkipSpaces(szCurrent,&szCurrent)) break;
			if (1 != strtoul10(szCurrent,&szCurrent))
			{
				DefaultLogger::get()->warn("SMD.version is not 1. This "
					"file format is not known. Continuing happily ...");
			}
			continue;
		}
		// "nodes\n" - Starts the node section
		if (TokenMatch(szCurrent,"nodes",5))
		{
			ParseNodesSection(szCurrent,&szCurrent);
			continue;
		}
		// "triangles\n" - Starts the triangle section
		if (TokenMatch(szCurrent,"triangles",9))
		{
			ParseTrianglesSection(szCurrent,&szCurrent);
			continue;
		}
		// "vertexanimation\n" - Starts the vertex animation section
		if (TokenMatch(szCurrent,"vertexanimation",15))
		{
			bHasUVs = false;
			ParseVASection(szCurrent,&szCurrent);
			continue;
		}
		// "skeleton\n" - Starts the skeleton section
		if (TokenMatch(szCurrent,"skeleton",8))
		{
			ParseSkeletonSection(szCurrent,&szCurrent);
			continue;
		}
		SkipLine(szCurrent,&szCurrent);
	}
	return;
}

// ------------------------------------------------------------------------------------------------
unsigned int SMDImporter::GetTextureIndex(const std::string& filename)
{
	unsigned int iIndex = 0;
	for (std::vector<std::string>::const_iterator
		i =  aszTextures.begin();
		i != aszTextures.end();++i,++iIndex)
	{
		// case-insensitive ... it's a path
		if (0 == ASSIMP_stricmp ( filename.c_str(),(*i).c_str()))return iIndex;
	}
	iIndex = (unsigned int)aszTextures.size();
	aszTextures.push_back(filename);
	return iIndex;
}

// ------------------------------------------------------------------------------------------------
// Parse the nodes section of the file
void SMDImporter::ParseNodesSection(const char* szCurrent,
	const char** szCurrentOut)
{
	for ( ;; )
	{
		// "end\n" - Ends the nodes section
		if (0 == ASSIMP_strincmp(szCurrent,"end",3) &&
			IsSpaceOrNewLine(*(szCurrent+3)))
		{
			szCurrent += 4;
			break;
		}
		ParseNodeInfo(szCurrent,&szCurrent);
	}
	SkipSpacesAndLineEnd(szCurrent,&szCurrent);
	*szCurrentOut = szCurrent;
}

// ------------------------------------------------------------------------------------------------
// Parse the triangles section of the file
void SMDImporter::ParseTrianglesSection(const char* szCurrent,
	const char** szCurrentOut)
{
	// Parse a triangle, parse another triangle, parse the next triangle ...
	// and so on until we reach a token that looks quite similar to "end"
	for ( ;; )
	{
		if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

		// "end\n" - Ends the triangles section
		if (TokenMatch(szCurrent,"end",3))
			break;
		ParseTriangle(szCurrent,&szCurrent);
	}
	SkipSpacesAndLineEnd(szCurrent,&szCurrent);
	*szCurrentOut = szCurrent;
}
// ------------------------------------------------------------------------------------------------
// Parse the vertex animation section of the file
void SMDImporter::ParseVASection(const char* szCurrent,
	const char** szCurrentOut)
{
	unsigned int iCurIndex = 0;
	for ( ;; )
	{
		if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

		// "end\n" - Ends the "vertexanimation" section
		if (TokenMatch(szCurrent,"end",3))
			break;
	
		// "time <n>\n" 
		if (TokenMatch(szCurrent,"time",4))
		{
			// NOTE: The doc says that time values COULD be negative ...
			// NOTE2: this is the shape key -> valve docs
			int iTime = 0;
			if(!ParseSignedInt(szCurrent,&szCurrent,iTime) || configFrameID != (unsigned int)iTime)break;
			SkipLine(szCurrent,&szCurrent);
		}
		else 
		{
			if(0 == iCurIndex)
			{
				asTriangles.push_back(SMD::Face());
			}
			if (++iCurIndex == 3)iCurIndex = 0;
			ParseVertex(szCurrent,&szCurrent,asTriangles.back().avVertices[iCurIndex],true);
		}
	}

	if (iCurIndex != 2 && !asTriangles.empty())
	{
		// we want to no degenerates, so throw this triangle away
		asTriangles.pop_back();
	}

	SkipSpacesAndLineEnd(szCurrent,&szCurrent);
	*szCurrentOut = szCurrent;
}
// ------------------------------------------------------------------------------------------------
// Parse the skeleton section of the file
void SMDImporter::ParseSkeletonSection(const char* szCurrent,
	const char** szCurrentOut)
{
	int iTime = 0;
	for ( ;; )
	{
		if(!SkipSpacesAndLineEnd(szCurrent,&szCurrent)) break;

		// "end\n" - Ends the skeleton section
		if (TokenMatch(szCurrent,"end",3))
			break;
	
		// "time <n>\n" - Specifies the current animation frame
		else if (TokenMatch(szCurrent,"time",4))
		{
			// NOTE: The doc says that time values COULD be negative ...
			if(!ParseSignedInt(szCurrent,&szCurrent,iTime))break;

			iSmallestFrame = std::min(iSmallestFrame,iTime);
			SkipLine(szCurrent,&szCurrent);
		}
		else ParseSkeletonElement(szCurrent,&szCurrent,iTime);
	}
	*szCurrentOut = szCurrent;	
}

// ------------------------------------------------------------------------------------------------
#define SMDI_PARSE_RETURN { \
	SkipLine(szCurrent,&szCurrent); \
	*szCurrentOut = szCurrent; \
	return; \
}
// ------------------------------------------------------------------------------------------------
// Parse a node line
void SMDImporter::ParseNodeInfo(const char* szCurrent,
	const char** szCurrentOut)
{
	unsigned int iBone  = 0;
	SkipSpacesAndLineEnd(szCurrent,&szCurrent);
	if(!ParseUnsignedInt(szCurrent,&szCurrent,iBone) || !SkipSpaces(szCurrent,&szCurrent))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone index");
		SMDI_PARSE_RETURN;
	}
	// add our bone to the list
	if (iBone >= asBones.size())asBones.resize(iBone+1);
	SMD::Bone& bone = asBones[iBone];

	bool bQuota = true;
	if ('\"' != *szCurrent)
	{
		LogWarning("Bone name is expcted to be enclosed in "
			"double quotation marks. ");
		bQuota = false;
	}
	else ++szCurrent;

	const char* szEnd = szCurrent;
	for ( ;; )
	{
		if (bQuota && '\"' == *szEnd)
		{
			iBone = (unsigned int)(szEnd - szCurrent);
			++szEnd;
			break;
		}
		else if (IsSpaceOrNewLine(*szEnd))
		{
			iBone = (unsigned int)(szEnd - szCurrent);
			break;
		}
		else if (!(*szEnd))
		{
			LogErrorNoThrow("Unexpected EOF/EOL while parsing bone name");
			SMDI_PARSE_RETURN;
		}
		++szEnd;
	}
	bone.mName = std::string(szCurrent,iBone);
	szCurrent = szEnd;

	// the only negative bone parent index that could occur is -1 AFAIK
	if(!ParseSignedInt(szCurrent,&szCurrent,(int&)bone.iParent))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone parent index. Assuming -1");
		SMDI_PARSE_RETURN;
	}

	// go to the beginning of the next line
	SMDI_PARSE_RETURN;
}

// ------------------------------------------------------------------------------------------------
// Parse a skeleton element
void SMDImporter::ParseSkeletonElement(const char* szCurrent,
	const char** szCurrentOut,int iTime)
{
	aiVector3D vPos;
	aiVector3D vRot;

	unsigned int iBone  = 0;
	if(!ParseUnsignedInt(szCurrent,&szCurrent,iBone))
	{
		DefaultLogger::get()->error("Unexpected EOF/EOL while parsing bone index");
		SMDI_PARSE_RETURN;
	}
	if (iBone >= asBones.size())
	{
		LogErrorNoThrow("Bone index in skeleton section is out of range");
		SMDI_PARSE_RETURN;
	}
	SMD::Bone& bone = asBones[iBone];

	bone.sAnim.asKeys.push_back(SMD::Bone::Animation::MatrixKey());
	SMD::Bone::Animation::MatrixKey& key = bone.sAnim.asKeys.back();

	key.dTime = (double)iTime;
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.x))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.x");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.y))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.y");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vPos.z))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.pos.z");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.x))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.x");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.y))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.y");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vRot.z))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing bone.rot.z");
		SMDI_PARSE_RETURN;
	}
	// build the transformation matrix of the key
	key.matrix.FromEulerAnglesXYZ(vRot.x,vRot.y,vRot.z);
	{
		aiMatrix4x4 mTemp;
		mTemp.a4 = vPos.x;
		mTemp.b4 = vPos.y;
		mTemp.c4 = vPos.z;
		key.matrix = key.matrix * mTemp;
	}

	// go to the beginning of the next line
	SMDI_PARSE_RETURN;
}

// ------------------------------------------------------------------------------------------------
// Parse a triangle
void SMDImporter::ParseTriangle(const char* szCurrent,
	const char** szCurrentOut)
{
	asTriangles.push_back(SMD::Face());
	SMD::Face& face = asTriangles.back();
	
	if(!SkipSpaces(szCurrent,&szCurrent))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing a triangle");
		return;
	}

	// read the texture file name
	const char* szLast = szCurrent;
	while (!IsSpaceOrNewLine(*szCurrent++));

	// ... and get the index that belongs to this file name
	face.iTexture = GetTextureIndex(std::string(szLast,(uintptr_t)szCurrent-(uintptr_t)szLast));

	SkipSpacesAndLineEnd(szCurrent,&szCurrent);

	// load three vertices
	for (unsigned int iVert = 0; iVert < 3;++iVert)
	{
		ParseVertex(szCurrent,&szCurrent,
			face.avVertices[iVert]);
	}
	*szCurrentOut = szCurrent;
}

// ------------------------------------------------------------------------------------------------
// Parse a float
bool SMDImporter::ParseFloat(const char* szCurrent,
	const char** szCurrentOut, float& out)
{
	if(!SkipSpaces(&szCurrent))
		return false;

	*szCurrentOut = fast_atoreal_move<float>(szCurrent,out);
	return true;
}

// ------------------------------------------------------------------------------------------------
// Parse an unsigned int
bool SMDImporter::ParseUnsignedInt(const char* szCurrent,
	const char** szCurrentOut, unsigned int& out)
{
	if(!SkipSpaces(&szCurrent))
		return false;

	out = strtoul10(szCurrent,szCurrentOut);
	return true;
}

// ------------------------------------------------------------------------------------------------
// Parse a signed int
bool SMDImporter::ParseSignedInt(const char* szCurrent,
	const char** szCurrentOut, int& out)
{
	if(!SkipSpaces(&szCurrent))
		return false;

	out = strtol10(szCurrent,szCurrentOut);
	return true;
}

// ------------------------------------------------------------------------------------------------
// Parse a vertex
void SMDImporter::ParseVertex(const char* szCurrent,
	const char** szCurrentOut, SMD::Vertex& vertex,
	bool bVASection /*= false*/)
{
	if (SkipSpaces(&szCurrent) && IsLineEnd(*szCurrent))
	{
		SkipSpacesAndLineEnd(szCurrent,&szCurrent);
		return ParseVertex(szCurrent,szCurrentOut,vertex,bVASection);
	}
	if(!ParseSignedInt(szCurrent,&szCurrent,(int&)vertex.iParentNode))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.parent");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.x))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.x");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.y))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.y");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.pos.z))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.pos.z");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.x))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.x");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.y))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.y");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.nor.z))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.nor.z");
		SMDI_PARSE_RETURN;
	}

	if (bVASection)SMDI_PARSE_RETURN;

	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.uv.x))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.uv.x");
		SMDI_PARSE_RETURN;
	}
	if(!ParseFloat(szCurrent,&szCurrent,(float&)vertex.uv.y))
	{
		LogErrorNoThrow("Unexpected EOF/EOL while parsing vertex.uv.y");
		SMDI_PARSE_RETURN;
	}

	// now read the number of bones affecting this vertex
	// all elements from now are fully optional, we don't need them
	unsigned int iSize = 0;
	if(!ParseUnsignedInt(szCurrent,&szCurrent,iSize))SMDI_PARSE_RETURN;
	vertex.aiBoneLinks.resize(iSize,std::pair<unsigned int, float>(0,0.0f));

	for (std::vector<std::pair<unsigned int, float> >::iterator
		i =  vertex.aiBoneLinks.begin();
		i != vertex.aiBoneLinks.end();++i)
	{
		if(!ParseUnsignedInt(szCurrent,&szCurrent,(*i).first))
			SMDI_PARSE_RETURN;
		if(!ParseFloat(szCurrent,&szCurrent,(*i).second))
			SMDI_PARSE_RETURN;
	}

	// go to the beginning of the next line
	SMDI_PARSE_RETURN;
}

#endif // !! ASSIMP_BUILD_NO_SMD_IMPORTER