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

Copyright (c) 2006-2012, assimp team

All rights reserved.

Redistribution and use of this software in source and binary forms, 
with or without modification, are permitted provided that the following 
conditions are met:

* Redistributions of source code must retain the above
  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
  following disclaimer in the documentation and/or other
  materials provided with the distribution.

* Neither the name of the assimp team, nor the names of its
  contributors may be used to endorse or promote products
  derived from this software without specific prior
  written permission of the assimp team.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
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---------------------------------------------------------------------------
*/

/** @file Implementation of the AC3D importer class */

#include "AssimpPCH.h"

#ifndef ASSIMP_BUILD_NO_AC_IMPORTER

// internal headers
#include "ACLoader.h"
#include "ParsingUtils.h"
#include "fast_atof.h"
#include "Subdivision.h"

using namespace Assimp;


// ------------------------------------------------------------------------------------------------
// skip to the next token
#define AI_AC_SKIP_TO_NEXT_TOKEN() \
	if (!SkipSpaces(&buffer)) \
	{ \
		DefaultLogger::get()->error("AC3D: Unexpected EOF/EOL"); \
		continue; \
	} 

// ------------------------------------------------------------------------------------------------
// read a string (may be enclosed in double quotation marks). buffer must point to "
#define AI_AC_GET_STRING(out) \
	++buffer; \
	const char* sz = buffer; \
	while ('\"' != *buffer) \
	{ \
		if (IsLineEnd( *buffer )) \
		{ \
			DefaultLogger::get()->error("AC3D: Unexpected EOF/EOL in string"); \
			out = "ERROR"; \
			break; \
		} \
		++buffer; \
	} \
	if (IsLineEnd( *buffer ))continue; \
	out = std::string(sz,(unsigned int)(buffer-sz)); \
	++buffer;


// ------------------------------------------------------------------------------------------------
// read 1 to n floats prefixed with an optional predefined identifier 
#define AI_AC_CHECKED_LOAD_FLOAT_ARRAY(name,name_length,num,out) \
	AI_AC_SKIP_TO_NEXT_TOKEN(); \
	if (name_length) \
	{ \
		if (strncmp(buffer,name,name_length) || !IsSpace(buffer[name_length])) \
		{ \
			DefaultLogger::get()->error("AC3D: Unexpexted token. " name " was expected."); \
			continue; \
		} \
		buffer += name_length+1; \
	} \
	for (unsigned int i = 0; i < num;++i) \
	{ \
		AI_AC_SKIP_TO_NEXT_TOKEN(); \
		buffer = fast_atoreal_move<float>(buffer,((float*)out)[i]); \
	}


// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
AC3DImporter::AC3DImporter()
{
	// nothing to be done here
}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
AC3DImporter::~AC3DImporter()
{
	// nothing to be done here
}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool AC3DImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const
{
	std::string extension = GetExtension(pFile);

	// fixme: are acc and ac3d *really* used? Some sources say they are
	if(extension == "ac" || extension == "ac3d" || extension == "acc") {
		return true;
	}
	if (!extension.length() || checkSig) {
		uint32_t token = AI_MAKE_MAGIC("AC3D");
		return CheckMagicToken(pIOHandler,pFile,&token,1,0);
	}
	return false;
}

// ------------------------------------------------------------------------------------------------
// Get list of file extensions handled by this loader
void AC3DImporter::GetExtensionList(std::set<std::string>& extensions)
{
	extensions.insert("ac");
	extensions.insert("acc");
	extensions.insert("ac3d");
}

// ------------------------------------------------------------------------------------------------
// Get a pointer to the next line from the file
bool AC3DImporter::GetNextLine( )
{
	SkipLine(&buffer); 
	return SkipSpaces(&buffer);
}

// ------------------------------------------------------------------------------------------------
// Parse an object section in an AC file
void AC3DImporter::LoadObjectSection(std::vector<Object>& objects)
{
	if (!TokenMatch(buffer,"OBJECT",6))
		return;

	SkipSpaces(&buffer);

	++mNumMeshes;

	objects.push_back(Object());
	Object& obj = objects.back();

	aiLight* light = NULL;
	if (!ASSIMP_strincmp(buffer,"light",5))
	{
		// This is a light source. Add it to the list
		mLights->push_back(light = new aiLight());

		// Return a point light with no attenuation
		light->mType = aiLightSource_POINT;
		light->mColorDiffuse = light->mColorSpecular = aiColor3D(1.f,1.f,1.f);
		light->mAttenuationConstant = 1.f;

		// Generate a default name for both the light source and the node
		// FIXME - what's the right way to print a size_t? Is 'zu' universally available? stick with the safe version.
		light->mName.length = ::sprintf(light->mName.data,"ACLight_%i",static_cast<unsigned int>(mLights->size())-1);
		obj.name = std::string( light->mName.data );

		DefaultLogger::get()->debug("AC3D: Light source encountered");
		obj.type = Object::Light;
	}
	else if (!ASSIMP_strincmp(buffer,"group",5))
	{
		obj.type = Object::Group;
	}
	else if (!ASSIMP_strincmp(buffer,"world",5))
	{
		obj.type = Object::World;
	}
	else obj.type = Object::Poly;
	while (GetNextLine())
	{
		if (TokenMatch(buffer,"kids",4))
		{
			SkipSpaces(&buffer);
			unsigned int num = strtoul10(buffer,&buffer);
			GetNextLine();
			if (num)
			{
				// load the children of this object recursively
				obj.children.reserve(num);
				for (unsigned int i = 0; i < num; ++i)
					LoadObjectSection(obj.children);
			}
			return;
		}
		else if (TokenMatch(buffer,"name",4))
		{
			SkipSpaces(&buffer);
			AI_AC_GET_STRING(obj.name);

			// If this is a light source, we'll also need to store
			// the name of the node in it.
			if (light)
			{
				light->mName.Set(obj.name);
			}
		}
		else if (TokenMatch(buffer,"texture",7))
		{
			SkipSpaces(&buffer);
			AI_AC_GET_STRING(obj.texture);
		}
		else if (TokenMatch(buffer,"texrep",6))
		{
			SkipSpaces(&buffer);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,2,&obj.texRepeat);
			if (!obj.texRepeat.x || !obj.texRepeat.y)
				obj.texRepeat = aiVector2D (1.f,1.f);
		}
		else if (TokenMatch(buffer,"texoff",6))
		{
			SkipSpaces(&buffer);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,2,&obj.texOffset);
		}
		else if (TokenMatch(buffer,"rot",3))
		{
			SkipSpaces(&buffer);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,9,&obj.rotation);
		}
		else if (TokenMatch(buffer,"loc",3))
		{
			SkipSpaces(&buffer);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,3,&obj.translation);
		}
		else if (TokenMatch(buffer,"subdiv",6))
		{
			SkipSpaces(&buffer);
			obj.subDiv = strtoul10(buffer,&buffer);
		}
		else if (TokenMatch(buffer,"crease",6))
		{
			SkipSpaces(&buffer);
			obj.crease = fast_atof(buffer);
		}
		else if (TokenMatch(buffer,"numvert",7))
		{
			SkipSpaces(&buffer);

			unsigned int t = strtoul10(buffer,&buffer);
			obj.vertices.reserve(t);
			for (unsigned int i = 0; i < t;++i)
			{
				if (!GetNextLine())
				{
					DefaultLogger::get()->error("AC3D: Unexpected EOF: not all vertices have been parsed yet");
					break;
				}
				else if (!IsNumeric(*buffer))
				{
					DefaultLogger::get()->error("AC3D: Unexpected token: not all vertices have been parsed yet");
					--buffer; // make sure the line is processed a second time
					break;
				}
				obj.vertices.push_back(aiVector3D());
				aiVector3D& v = obj.vertices.back();
				AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,3,&v.x);
			}
		}
		else if (TokenMatch(buffer,"numsurf",7))
		{
			SkipSpaces(&buffer);
			
			bool Q3DWorkAround = false;

			const unsigned int t = strtoul10(buffer,&buffer);
			obj.surfaces.reserve(t);
			for (unsigned int i = 0; i < t;++i)
			{
				GetNextLine();
				if (!TokenMatch(buffer,"SURF",4))
				{
					// FIX: this can occur for some files - Quick 3D for 
					// example writes no surf chunks
					if (!Q3DWorkAround)
					{
						DefaultLogger::get()->warn("AC3D: SURF token was expected");
						DefaultLogger::get()->debug("Continuing with Quick3D Workaround enabled");
					}
					--buffer; // make sure the line is processed a second time
					// break; --- see fix notes above

					Q3DWorkAround = true;
				}
				SkipSpaces(&buffer);
				obj.surfaces.push_back(Surface());
				Surface& surf = obj.surfaces.back();
				surf.flags = strtoul_cppstyle(buffer);
			
				while (1)
				{
					if(!GetNextLine())
					{
						DefaultLogger::get()->error("AC3D: Unexpected EOF: surface is incomplete");
						break;
					}
					if (TokenMatch(buffer,"mat",3))
					{
						SkipSpaces(&buffer);
						surf.mat = strtoul10(buffer);
					}
					else if (TokenMatch(buffer,"refs",4))
					{
						// --- see fix notes above
						if (Q3DWorkAround)
						{
							if (!surf.entries.empty())
							{
								buffer -= 6;
								break;
							}
						}

						SkipSpaces(&buffer);
						const unsigned int m = strtoul10(buffer);
						surf.entries.reserve(m);

						obj.numRefs += m;

						for (unsigned int k = 0; k < m; ++k)
						{
							if(!GetNextLine())
							{
								DefaultLogger::get()->error("AC3D: Unexpected EOF: surface references are incomplete");
								break;
							}
							surf.entries.push_back(Surface::SurfaceEntry());
							Surface::SurfaceEntry& entry = surf.entries.back();

							entry.first = strtoul10(buffer,&buffer);
							SkipSpaces(&buffer);
							AI_AC_CHECKED_LOAD_FLOAT_ARRAY("",0,2,&entry.second);
						}
					}
					else 
					{

						--buffer; // make sure the line is processed a second time
						break;
					}
				}
			}
		}
	}
	DefaultLogger::get()->error("AC3D: Unexpected EOF: \'kids\' line was expected");
}

// ------------------------------------------------------------------------------------------------
// Convert a material from AC3DImporter::Material to aiMaterial
void AC3DImporter::ConvertMaterial(const Object& object,
	const Material& matSrc,
	aiMaterial& matDest)
{
	aiString s;

	if (matSrc.name.length())
	{
		s.Set(matSrc.name);
		matDest.AddProperty(&s,AI_MATKEY_NAME);
	}
	if (object.texture.length())
	{
		s.Set(object.texture);
		matDest.AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(0));

		// UV transformation
		if (1.f != object.texRepeat.x || 1.f != object.texRepeat.y ||
			object.texOffset.x        || object.texOffset.y)
		{
			aiUVTransform transform;
			transform.mScaling = object.texRepeat;
			transform.mTranslation = object.texOffset;
			matDest.AddProperty(&transform,1,AI_MATKEY_UVTRANSFORM_DIFFUSE(0));
		}
	}

	matDest.AddProperty<aiColor3D>(&matSrc.rgb,1, AI_MATKEY_COLOR_DIFFUSE);
	matDest.AddProperty<aiColor3D>(&matSrc.amb,1, AI_MATKEY_COLOR_AMBIENT);
	matDest.AddProperty<aiColor3D>(&matSrc.emis,1,AI_MATKEY_COLOR_EMISSIVE);
	matDest.AddProperty<aiColor3D>(&matSrc.spec,1,AI_MATKEY_COLOR_SPECULAR);

	int n;
	if (matSrc.shin)
	{
		n = aiShadingMode_Phong;
		matDest.AddProperty<float>(&matSrc.shin,1,AI_MATKEY_SHININESS);
	}
	else n = aiShadingMode_Gouraud;
	matDest.AddProperty<int>(&n,1,AI_MATKEY_SHADING_MODEL);

	float f = 1.f - matSrc.trans;
	matDest.AddProperty<float>(&f,1,AI_MATKEY_OPACITY);
}

// ------------------------------------------------------------------------------------------------
// Converts the loaded data to the internal verbose representation
aiNode* AC3DImporter::ConvertObjectSection(Object& object,
	std::vector<aiMesh*>& meshes,
	std::vector<aiMaterial*>& outMaterials,
	const std::vector<Material>& materials,
	aiNode* parent)
{
	aiNode* node = new aiNode();
	node->mParent = parent;
	if (object.vertices.size())
	{
		if (!object.surfaces.size() || !object.numRefs)
		{
			/* " An object with 7 vertices (no surfaces, no materials defined). 
			     This is a good way of getting point data into AC3D. 
			     The Vertex->create convex-surface/object can be used on these
			     vertices to 'wrap' a 3d shape around them "
				 (http://www.opencity.info/html/ac3dfileformat.html)

				 therefore: if no surfaces are defined return point data only
			 */

			DefaultLogger::get()->info("AC3D: No surfaces defined in object definition, "
				"a point list is returned");

			meshes.push_back(new aiMesh());
			aiMesh* mesh = meshes.back();

			mesh->mNumFaces = mesh->mNumVertices = (unsigned int)object.vertices.size();
			aiFace* faces = mesh->mFaces = new aiFace[mesh->mNumFaces];
			aiVector3D* verts = mesh->mVertices = new aiVector3D[mesh->mNumVertices];

			for (unsigned int i = 0; i < mesh->mNumVertices;++i,++faces,++verts)
			{
				*verts = object.vertices[i];
				faces->mNumIndices = 1;
				faces->mIndices = new unsigned int[1];
				faces->mIndices[0] = i;
			}

			// use the primary material in this case. this should be the
			// default material if all objects of the file contain points
			// and no faces.
			mesh->mMaterialIndex = 0;
			outMaterials.push_back(new aiMaterial());
			ConvertMaterial(object, materials[0], *outMaterials.back());
		}
		else
		{
			// need to generate one or more meshes for this object.
			// find out how many different materials we have
			typedef std::pair< unsigned int, unsigned int > IntPair;
			typedef std::vector< IntPair > MatTable;
			MatTable needMat(materials.size(),IntPair(0,0));

			std::vector<Surface>::iterator it,end = object.surfaces.end();
			std::vector<Surface::SurfaceEntry>::iterator it2,end2;

			for (it = object.surfaces.begin(); it != end; ++it)
			{
				register unsigned int idx = (*it).mat;
				if (idx >= needMat.size())
				{
					DefaultLogger::get()->error("AC3D: material index is out of range");
					idx = 0;
				}
				if ((*it).entries.empty())
				{
					DefaultLogger::get()->warn("AC3D: surface her zero vertex references");
				}

				// validate all vertex indices to make sure we won't crash here
				for (it2  = (*it).entries.begin(),
					 end2 = (*it).entries.end(); it2 != end2; ++it2)
				{
					if ((*it2).first >= object.vertices.size())
					{
						DefaultLogger::get()->warn("AC3D: Invalid vertex reference");
						(*it2).first = 0;
					}
				}

				if (!needMat[idx].first)++node->mNumMeshes;

				switch ((*it).flags & 0xf)
				{
					// closed line
				case 0x1:

					needMat[idx].first  += (unsigned int)(*it).entries.size();
					needMat[idx].second += (unsigned int)(*it).entries.size()<<1u;
					break;

					// unclosed line
				case 0x2:

					needMat[idx].first  += (unsigned int)(*it).entries.size()-1;
					needMat[idx].second += ((unsigned int)(*it).entries.size()-1)<<1u;
					break;

					// 0 == polygon, else unknown
				default:

					if ((*it).flags & 0xf)
					{
						DefaultLogger::get()->warn("AC3D: The type flag of a surface is unknown");
						(*it).flags &= ~(0xf);
					}

					// the number of faces increments by one, the number
					// of vertices by surface.numref.
					needMat[idx].first++;
					needMat[idx].second += (unsigned int)(*it).entries.size();
				};
			}
			unsigned int* pip = node->mMeshes = new unsigned int[node->mNumMeshes];
			unsigned int mat = 0;
			const size_t oldm = meshes.size();
			for (MatTable::const_iterator cit = needMat.begin(), cend = needMat.end();
				cit != cend; ++cit, ++mat)
			{
				if (!(*cit).first)continue;

				// allocate a new aiMesh object
				*pip++ = (unsigned int)meshes.size();
				aiMesh* mesh = new aiMesh();
				meshes.push_back(mesh);

				mesh->mMaterialIndex = (unsigned int)outMaterials.size();
				outMaterials.push_back(new aiMaterial());
				ConvertMaterial(object, materials[mat], *outMaterials.back());

				// allocate storage for vertices and normals
				mesh->mNumFaces = (*cit).first;
				aiFace* faces = mesh->mFaces = new aiFace[mesh->mNumFaces];

				mesh->mNumVertices = (*cit).second;
				aiVector3D* vertices = mesh->mVertices = new aiVector3D[mesh->mNumVertices];
				unsigned int cur = 0;

				// allocate UV coordinates, but only if the texture name for the
				// surface is not empty
				aiVector3D* uv = NULL;
				if(object.texture.length())
				{
					uv = mesh->mTextureCoords[0] = new aiVector3D[mesh->mNumVertices];
					mesh->mNumUVComponents[0] = 2;
				}

				for (it = object.surfaces.begin(); it != end; ++it)
				{
					if (mat == (*it).mat)
					{
						const Surface& src = *it;

						// closed polygon
						unsigned int type = (*it).flags & 0xf; 
						if (!type)
						{
							aiFace& face = *faces++;
							if((face.mNumIndices = (unsigned int)src.entries.size()))
							{
								face.mIndices = new unsigned int[face.mNumIndices];
								for (unsigned int i = 0; i < face.mNumIndices;++i,++vertices)
								{
									const Surface::SurfaceEntry& entry = src.entries[i];
									face.mIndices[i] = cur++;

									// copy vertex positions
									*vertices = object.vertices[entry.first] + object.translation;


									// copy texture coordinates 
									if (uv)
									{
										uv->x =  entry.second.x;
										uv->y =  entry.second.y;
										++uv;
									}
								}
							}
						}
						else
						{
							
							it2  = (*it).entries.begin();

							// either a closed or an unclosed line
							register unsigned int tmp = (unsigned int)(*it).entries.size();
							if (0x2 == type)--tmp;
							for (unsigned int m = 0; m < tmp;++m)
							{
								aiFace& face = *faces++;

								face.mNumIndices = 2;
								face.mIndices = new unsigned int[2];
								face.mIndices[0] = cur++;
								face.mIndices[1] = cur++;

								// copy vertex positions
								*vertices++ = object.vertices[(*it2).first];
								
								// copy texture coordinates 
								if (uv)
								{
									uv->x =  (*it2).second.x;
									uv->y =  (*it2).second.y;
									++uv;
								}


								if (0x1 == type && tmp-1 == m)
								{
									// if this is a closed line repeat its beginning now
									it2  = (*it).entries.begin();
								}
								else ++it2;

								// second point
								*vertices++ = object.vertices[(*it2).first];

								if (uv)
								{
									uv->x =  (*it2).second.x;
									uv->y =  (*it2).second.y;
									++uv;
								}
							}
						}
					}
				}
			}

			// Now apply catmull clark subdivision if necessary. We split meshes into
			// materials which is not done by AC3D during smoothing, so we need to
			// collect all meshes using the same material group.
			if (object.subDiv)	{
				if (configEvalSubdivision) {
					boost::scoped_ptr<Subdivider> div(Subdivider::Create(Subdivider::CATMULL_CLARKE));
					DefaultLogger::get()->info("AC3D: Evaluating subdivision surface: "+object.name);

					std::vector<aiMesh*> cpy(meshes.size()-oldm,NULL);
					div->Subdivide(&meshes[oldm],cpy.size(),&cpy.front(),object.subDiv,true);
					std::copy(cpy.begin(),cpy.end(),meshes.begin()+oldm);

					// previous meshes are deleted vy Subdivide().
				}
				else {
					DefaultLogger::get()->info("AC3D: Letting the subdivision surface untouched due to my configuration: "
						+object.name);
				}
			}
		}
	}

	if (object.name.length())
		node->mName.Set(object.name);
	else
	{
		// generate a name depending on the type of the node
		switch (object.type)
		{
		case Object::Group:
			node->mName.length = ::sprintf(node->mName.data,"ACGroup_%i",groups++);
			break;
		case Object::Poly:
			node->mName.length = ::sprintf(node->mName.data,"ACPoly_%i",polys++);
			break;
		case Object::Light:
			node->mName.length = ::sprintf(node->mName.data,"ACLight_%i",lights++);
			break;

			// there shouldn't be more than one world, but we don't care
		case Object::World: 
			node->mName.length = ::sprintf(node->mName.data,"ACWorld_%i",worlds++);
			break;
		}
	}


	// setup the local transformation matrix of the object
	// compute the transformation offset to the parent node
	node->mTransformation = aiMatrix4x4 ( object.rotation );

	if (object.type == Object::Group || !object.numRefs)
	{
		node->mTransformation.a4 = object.translation.x;
		node->mTransformation.b4 = object.translation.y;
		node->mTransformation.c4 = object.translation.z;
	}

	// add children to the object
	if (object.children.size())
	{
		node->mNumChildren = (unsigned int)object.children.size();
		node->mChildren = new aiNode*[node->mNumChildren];
		for (unsigned int i = 0; i < node->mNumChildren;++i)
		{
			node->mChildren[i] = ConvertObjectSection(object.children[i],meshes,outMaterials,materials,node);
		}
	}

	return node;
}

// ------------------------------------------------------------------------------------------------
void AC3DImporter::SetupProperties(const Importer* pImp)
{
	configSplitBFCull = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_AC_SEPARATE_BFCULL,1) ? true : false;
	configEvalSubdivision =  pImp->GetPropertyInteger(AI_CONFIG_IMPORT_AC_EVAL_SUBDIVISION,1) ? true : false;
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void AC3DImporter::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 AC3D file " + pFile + ".");

	// allocate storage and copy the contents of the file to a memory buffer
	std::vector<char> mBuffer2;
	TextFileToBuffer(file.get(),mBuffer2);

	buffer = &mBuffer2[0];
	mNumMeshes = 0;

	lights = polys = worlds = groups = 0;

	if (::strncmp(buffer,"AC3D",4)) {
		throw DeadlyImportError("AC3D: No valid AC3D file, magic sequence not found");
	}

	// print the file format version to the console
	unsigned int version = HexDigitToDecimal( buffer[4] );
	char msg[3];
	ASSIMP_itoa10(msg,3,version);
	DefaultLogger::get()->info(std::string("AC3D file format version: ") + msg);

	std::vector<Material> materials;
	materials.reserve(5);

	std::vector<Object> rootObjects;
	rootObjects.reserve(5);

	std::vector<aiLight*> lights;
	mLights = & lights;

	while (GetNextLine())
	{
		if (TokenMatch(buffer,"MATERIAL",8))
		{
			materials.push_back(Material());
			Material& mat = materials.back();

			// manually parse the material ... sscanf would use the buldin atof ...
			// Format: (name) rgb %f %f %f  amb %f %f %f  emis %f %f %f  spec %f %f %f  shi %d  trans %f

			AI_AC_SKIP_TO_NEXT_TOKEN();
			if ('\"' == *buffer)
			{
				AI_AC_GET_STRING(mat.name);
				AI_AC_SKIP_TO_NEXT_TOKEN();
			}

			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("rgb",3,3,&mat.rgb);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("amb",3,3,&mat.amb);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("emis",4,3,&mat.emis);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("spec",4,3,&mat.spec);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("shi",3,1,&mat.shin);
			AI_AC_CHECKED_LOAD_FLOAT_ARRAY("trans",5,1,&mat.trans);
		}
		LoadObjectSection(rootObjects);
	}

	if (rootObjects.empty() || !mNumMeshes)
	{
		throw DeadlyImportError("AC3D: No meshes have been loaded");
	}
	if (materials.empty())
	{
		DefaultLogger::get()->warn("AC3D: No material has been found");
		materials.push_back(Material());
	}

	mNumMeshes += (mNumMeshes>>2u) + 1;
	std::vector<aiMesh*> meshes;
	meshes.reserve(mNumMeshes);

	std::vector<aiMaterial*> omaterials;
	materials.reserve(mNumMeshes);

	// generate a dummy root if there are multiple objects on the top layer
	Object* root;
	if (1 == rootObjects.size())
		root = &rootObjects[0];
	else
	{
		root = new Object();
	}

	// now convert the imported stuff to our output data structure
	pScene->mRootNode = ConvertObjectSection(*root,meshes,omaterials,materials);
	if (1 != rootObjects.size())delete root;

	if (!::strncmp( pScene->mRootNode->mName.data, "Node", 4))
		pScene->mRootNode->mName.Set("<AC3DWorld>");

	// copy meshes
	if (meshes.empty())
	{
		throw DeadlyImportError("An unknown error occured during converting");
	}
	pScene->mNumMeshes = (unsigned int)meshes.size();
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];
	::memcpy(pScene->mMeshes,&meshes[0],pScene->mNumMeshes*sizeof(void*));

	// copy materials
	pScene->mNumMaterials = (unsigned int)omaterials.size();
	pScene->mMaterials = new aiMaterial*[pScene->mNumMaterials];
	::memcpy(pScene->mMaterials,&omaterials[0],pScene->mNumMaterials*sizeof(void*));

	// copy lights
	pScene->mNumLights = (unsigned int)lights.size();
	if (lights.size())
	{
		pScene->mLights = new aiLight*[lights.size()];
		::memcpy(pScene->mLights,&lights[0],lights.size()*sizeof(void*));
	}
}

#endif //!defined ASSIMP_BUILD_NO_AC_IMPORTER