/****************************************************************************
* VCGLib                                                            o o     *
* Visual and Computer Graphics Library                            o     o   *
*                                                                _   O  _   *
* Copyright(C) 2004-2016                                           \/)\/    *
* Visual Computing Lab                                            /\/|      *
* ISTI - Italian National Research Council                           |      *
*                                                                    \      *
* All rights reserved.                                                      *
*                                                                           *
* This program is free software; you can redistribute it and/or modify      *
* it under the terms of the GNU General Public License as published by      *
* the Free Software Foundation; either version 2 of the License, or         *
* (at your option) any later version.                                       *
*                                                                           *
* 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 (http://www.gnu.org/licenses/gpl.txt)          *
* for more details.                                                         *
*                                                                           *
****************************************************************************/


#ifndef __VCGLIB_IMPORT_OBJ
#define __VCGLIB_IMPORT_OBJ

#include <wrap/callback.h>
#include <wrap/io_trimesh/io_mask.h>
#include <wrap/io_trimesh/io_material.h>
#include <wrap/io_trimesh/io_fan_tessellator.h>
#ifdef __gl_h_
#include <wrap/gl/glu_tesselator.h>
#endif
#include <vcg/space/color4.h>


#include <fstream>
#include <string>
#include <vector>


namespace vcg {
    namespace tri {
        namespace io {

            /**
            This class encapsulate a filter for importing obj (Alias Wavefront) meshes.
            Warning: this code assume little endian (PC) architecture!!!
            */
            template <class OpenMeshType>
            class ImporterOBJ
            {
            public:
                static int &MRGBLineCount(){static int _MRGBLineCount=0; return _MRGBLineCount;}

                typedef typename OpenMeshType::VertexPointer VertexPointer;
                typedef typename OpenMeshType::ScalarType ScalarType;
                typedef typename OpenMeshType::VertexType VertexType;
                typedef typename OpenMeshType::EdgeType   EdgeType;
                typedef typename OpenMeshType::FaceType FaceType;
                typedef typename OpenMeshType::VertexIterator VertexIterator;
                typedef typename OpenMeshType::FaceIterator FaceIterator;
                typedef typename OpenMeshType::CoordType CoordType;

                class Info
                {
                public:

                    Info()
                    {
                        mask	= 0;
                        cb		= 0;
                        numTexCoords=0;
                    }

                    /// It returns a bit mask describing the field preesnt in the ply file
                    int mask;

                    /// a Simple callback that can be used for long obj parsing.
                    // it returns the current position, and formats a string with a description of what th efunction is doing (loading vertexes, faces...)
                    CallBackPos *cb;

                    /// number of vertices
                    int numVertices;
                    /// number of edges
                    int numEdges;
                    /// number of faces (the number of triangles could be
                    /// larger in presence of polygonal faces
                    int numFaces;
                    /// number of texture coords indexes
                    int numTexCoords;
                    /// number of normals
                    int numNormals;

                }; // end class


                //struct OBJFacet
                //{
                //  CoordType n;
                //	CoordType t;
                //  CoordType v[3];
                //
                //	short attr;  // material index
                //};
                struct ObjIndexedFace
                {
                    void set(const int & num){v.resize(num);n.resize(num); t.resize(num);}
                    std::vector<int> v;
                    std::vector<int> n;
                    std::vector<int> t;
                    int tInd;
                    bool  edge[3];// useless if the face is a polygon, no need to have variable length array
                    Color4b c;
                };

                struct ObjEdge
                {
                    int v0;
                    int v1;
                };

                struct ObjTexCoord
                {
                    float u;
                    float v;
                };

                enum OBJError {
                    // Successfull opening
                    E_NOERROR                           = 0*2+0,  //  A*2+B  (A position of correspondig string in the array, B=1 if not critical)

                    // Non Critical Errors (only odd numbers)
                    E_NON_CRITICAL_ERROR                = 0*2+1,
                    E_MATERIAL_FILE_NOT_FOUND           = 1*2+1,
                    E_MATERIAL_NOT_FOUND                = 2*2+1,
                    E_TEXTURE_NOT_FOUND                 = 3*2+1,
                    E_VERTICES_WITH_SAME_IDX_IN_FACE    = 4*2+1,
                    E_LESS_THAN_3_VERT_IN_FACE          = 5*2+1,

                    // Critical Opening Errors (only even numbers)
                    E_CANTOPEN                          = 6*2+0,
                    E_UNEXPECTED_EOF                     = 7*2+0,
                    E_ABORTED                           = 8*2+0,
                    E_NO_VERTEX                         = 9*2+0,
                    E_NO_FACE                           =10*2+0,
                    E_BAD_VERTEX_STATEMENT              =11*2+0,
                    E_BAD_VERT_TEX_STATEMENT            =12*2+0,
                    E_BAD_VERT_NORMAL_STATEMENT         =13*2+0,
                    E_BAD_VERT_INDEX                    =14*2+0,
                    E_BAD_VERT_TEX_INDEX                =15*2+0,
                    E_BAD_VERT_NORMAL_INDEX             =16*2+0,
                    E_LESS_THAN_4_VERT_IN_QUAD          =17*2+0
                };

                // to check if a given error is critical or not.
                static bool ErrorCritical(int err)
                {
                    if (err==0) return false;
                    if (err&1) return false;
                    return true;
                }

                static const char* ErrorMsg(int error)
                {
                    const int MAXST = 18;
                    static const char* obj_error_msg[MAXST] =
                    {
                        /*  0 */ "No errors",

                        /*  1 */ "Material library file wrong or not found, a default white material is used",
                        /*  2 */ "Some materials definitions were not found, a default white material is used where no material was available",
                        /*  3 */ "Texture file not found",
                        /*  4 */ "Identical vertex indices found in the same faces -- faces ignored",
                        /*  5 */ "Faces with fewer than 3 vertices  -- faces ignored",

                        /*  6 */ "Can't open file",
                        /*  7 */ "Premature End of File. File truncated?",
                        /*  8 */ "Loading aborted by user",
                        /*  9 */ "No vertex found",
                        /* 10 */ "No face found",
                        /* 11 */ "Vertex statement with fewer than 3 coords",
                        /* 12 */ "Texture coords statement with fewer than 2 coords",
                        /* 13 */ "Vertex normal statement with fewer than 3 coords",
                        /* 14 */ "Bad vertex index in face",
                        /* 15 */ "Bad texture coords index in face",
                        /* 16 */ "Bad vertex normal index in face",
                        /* 17 */ "Quad faces with number of corners different from 4"
                    };

                    error >>= 1;

                    if( (error>=MAXST) || (error<0) ) return "Unknown error";
                    else return obj_error_msg[error];
                }

                // Helper functions that checks the range of indexes
                // putting them in the correct range if less than zero (as in the obj style)

                static bool GoodObjIndex(int &index, const int maxVal)
                {
                    if (index > maxVal)	return false;
                    if (index < 0)
                    {
                        index += maxVal+1;
                        if (index<0 || index > maxVal)	return false;
                    }
                    return true;
                }

                static int Open(OpenMeshType &mesh, const char *filename, int &loadmask, CallBackPos *cb=0)
                {
                    Info oi;
                    oi.mask=0;
                    oi.cb=cb;
                    int ret=Open(mesh,filename,oi);
                    loadmask=oi.mask;
                    return ret;
                }

                /*!
                * Opens an object file (in ascii format) and populates the mesh passed as first
                * accordingly to read data
                * \param m The mesh model to be populated with data stored into the file
                * \param filename The name of the file to be opened
                * \param oi A structure containing infos about the object to be opened
                */
                static int Open( OpenMeshType &m, const char * filename, Info &oi)
                {
                    int result = E_NOERROR;

                    m.Clear();
                    CallBackPos *cb = oi.cb;

                    // if LoadMask has not been called yet, we call it here
                    if (oi.mask == 0)
                        LoadMask(filename, oi);

                    const int inputMask = oi.mask;
                    Mask::ClampMask<OpenMeshType>(m,oi.mask);

                    if (oi.numVertices == 0)
                        return E_NO_VERTEX;

                    // Commented out this test. You should be allowed to load point clouds.
                    //if (oi.numFaces == 0)
                    //	return E_NO_FACE;


                    std::ifstream stream(filename);
                    if (stream.fail())
                    {
                        stream.close();
                        return E_CANTOPEN;
                    }
                    std::vector<Material>	materials;  // materials vector
                    std::vector<ObjTexCoord>	texCoords;  // texture coordinates
                    std::vector<CoordType>  normals;		// vertex normals
                    std::vector<ObjIndexedFace> indexedFaces;
                    std::vector< std::string > tokens;
                    std::string	header;

                    short currentMaterialIdx = 0;			// index of current material into materials vector
                    Color4b currentColor=Color4b::LightGray;	// we declare this outside code block since other
                    // triangles of this face will share the same color

                    Material defaultMaterial;					// default material: white
                    materials.push_back(defaultMaterial);

                    int numVertices  = 0;  // stores the number of vertices been read till now
                    int numEdges     = 0;  // stores the number of edges read till now
                    int numTriangles = 0;  // stores the number of faces been read till now
                    int numTexCoords = 0;  // stores the number of texture coordinates been read till now
                    int numVNormals	 = 0;  // stores the number of vertex normals been read till now

                    int numVerticesPlusFaces = oi.numVertices + oi.numFaces;
                    int extraTriangles=0;
                    // vertices and faces allocation
                    VertexIterator vi = vcg::tri::Allocator<OpenMeshType>::AddVertices(m,oi.numVertices);
                    //FaceIterator   fi = Allocator<OpenMeshType>::AddFaces(m,oi.numFaces);
                    // edges found
                    std::vector<ObjEdge> ev;
                    std::vector<Color4b> vertexColorVector;
                    ObjIndexedFace	ff;
                    const char *loadingStr = "Loading";
                    while (!stream.eof())
                    {
                        tokens.clear();
                        TokenizeNextLine(stream, tokens,&vertexColorVector);

                        unsigned int numTokens = static_cast<unsigned int>(tokens.size());
                        if (numTokens > 0)
                        {
                            header.clear();
                            header = tokens[0];

                            // callback invocation, abort loading process if the call returns false
                            if ((cb !=NULL) && (((numTriangles + numVertices)%100)==0) && !(*cb)((100*(numTriangles + numVertices))/numVerticesPlusFaces, loadingStr))
                            {
                                stream.close();
                                return E_ABORTED;
                            }
                            if (header.compare("v")==0)	// vertex
                            {
                                loadingStr="Vertex Loading";
                                if (numTokens < 4)
                                {
                                    stream.close();
                                    return E_BAD_VERTEX_STATEMENT;
                                }
                                (*vi).P()[0] = (ScalarType) atof(tokens[1].c_str());
                                (*vi).P()[1] = (ScalarType) atof(tokens[2].c_str());
                                (*vi).P()[2] = (ScalarType) atof(tokens[3].c_str());
                                ++numVertices;

                                // assigning vertex color
                                // ----------------------
                                if (((oi.mask & vcg::tri::io::Mask::IOM_VERTCOLOR) != 0) && (HasPerVertexColor(m)))
                                {
                                    if(numTokens>=7)
                                    {
                                        ScalarType rf(atof(tokens[4].c_str())), gf(atof(tokens[5].c_str())), bf(atof(tokens[6].c_str()));
                                        ScalarType scaling = (rf<=1 && gf<=1 && bf<=1) ? 255. : 1;

                                        unsigned char r			= (unsigned char) ((ScalarType) atof(tokens[4].c_str()) * scaling);
                                        unsigned char g			= (unsigned char) ((ScalarType) atof(tokens[5].c_str()) * scaling);
                                        unsigned char b			= (unsigned char) ((ScalarType) atof(tokens[6].c_str()) * scaling);
                                        unsigned char alpha = (unsigned char) ((numTokens>=8 ? (ScalarType) atof(tokens[7].c_str()) : 1)  * scaling);
                                        (*vi).C() = Color4b(r, g, b, alpha);
                                    }
                                    else
                                    {
                                        (*vi).C() = currentColor;
                                    }
                                }

                                ++vi;  // move to next vertex iterator
                            }
                            else if (header.compare("vt")==0)	// vertex texture coords
                            {
                                loadingStr="Vertex Texture Loading";

                                if (numTokens < 3)
                                {
                                    stream.close();
                                    return E_BAD_VERT_TEX_STATEMENT;
                                }
                                ObjTexCoord t;
                                t.u = static_cast<float>(atof(tokens[1].c_str()));
                                t.v = static_cast<float>(atof(tokens[2].c_str()));
                                texCoords.push_back(t);

                                numTexCoords++;
                            }
                            else if (header.compare("vn")==0)  // vertex normal
                            {
                                loadingStr="Vertex Normal Loading";

                                if (numTokens != 4)
                                {
                                    stream.close();
                                    return E_BAD_VERT_NORMAL_STATEMENT;
                                }
                                CoordType n;
                                n[0] = (ScalarType) atof(tokens[1].c_str());
                                n[1] = (ScalarType) atof(tokens[2].c_str());
                                n[2] = (ScalarType) atof(tokens[3].c_str());
                                normals.push_back(n);

                                numVNormals++;
                            }
                            else if ( header.compare("l")==0 )
                            {
                                loadingStr = "Edge Loading";

                                if (numTokens < 3)
                                {
                                    result = E_LESS_THAN_3_VERT_IN_FACE; // TODO add proper/handling error code
                                    continue;
                                }

                                ObjEdge e = { (atoi(tokens[1].c_str()) - 1),
                                              (atoi(tokens[2].c_str()) - 1) };
                                ev.push_back(e);

                                numEdges++;
                            }
                            else if( (header.compare("f")==0) || (header.compare("q")==0) )  // face
                            {
                                loadingStr="Face Loading";

                                int vertexesPerFace = static_cast<int>(tokens.size()-1);

                                bool QuadFlag = false; // QOBJ format by Silva et al for simply storing quadrangular meshes.
                                if(header.compare("q")==0) {
                                    QuadFlag=true;
                                    if (vertexesPerFace != 4) {
                                        stream.close();
                                        return E_LESS_THAN_4_VERT_IN_QUAD;
                                    }
                                }


                                if (vertexesPerFace < 3) {
                                    // face with fewer than 3 vertices found: ignore this face
                                    extraTriangles--;
                                    result = E_LESS_THAN_3_VERT_IN_FACE;
                                    continue;
                                }


                                if( (vertexesPerFace>3) && OpenMeshType::FaceType::HasPolyInfo() )
                                {
                                    //_BEGIN___ if  you are loading a GENERIC POLYGON mesh
                                    ff.set(vertexesPerFace);
                                    for(int i=0;i<vertexesPerFace;++i) { // remember index starts from 1 instead of 0
                                        SplitToken(tokens[i+1], ff.v[i], ff.n[i], ff.t[i], inputMask);
                                        if(QuadFlag) ff.v[i]++; // NOTE THAT THE STUPID QOBJ FORMAT IS ZERO INDEXED!!!!
                                    }
                                    if ( oi.mask & vcg::tri::io::Mask::IOM_WEDGTEXCOORD )
                                    {
                                        // verifying validity of texture coords indices
                                        for(int i=0;i<vertexesPerFace;i++)
                                            if(!GoodObjIndex(ff.t[i],oi.numTexCoords))
                                            {
                                                stream.close();
                                                return E_BAD_VERT_TEX_INDEX;
                                            }
                                        ff.tInd=materials[currentMaterialIdx].index;
                                    }

                                    // verifying validity of vertex indices
                                    std::vector<int> tmp = ff.v;
                                    std::sort(tmp.begin(),tmp.end());
                                    std::unique(tmp.begin(),tmp.end());
                                    if(tmp.size() != ff.v.size()) {
                                        result = E_VERTICES_WITH_SAME_IDX_IN_FACE;
                                        extraTriangles--;
                                        continue;
                                    }

                                    for(int i=0;i<vertexesPerFace;i++)
                                        if(!GoodObjIndex(ff.v[i],numVertices))
                                        {
                                            stream.close();
                                            return E_BAD_VERT_INDEX;
                                        }

                                    if(( oi.mask & vcg::tri::io::Mask::IOM_WEDGNORMAL ) ||
                                       ( oi.mask & vcg::tri::io::Mask::IOM_VERTNORMAL  ) )
                                    {
                                        // verifying validity of vertex normal indices
                                        for(int i=0;i<vertexesPerFace;i++)
                                            if(!GoodObjIndex(ff.n[i],numVNormals))
                                            {
                                                stream.close();
                                                return E_BAD_VERT_NORMAL_INDEX;
                                            }
                                    }


                                    if( oi.mask & vcg::tri::io::Mask::IOM_FACECOLOR) // assigning face color
                                        ff.c = currentColor;

                                    ++numTriangles;
                                    indexedFaces.push_back(ff);

                                    //_END  ___ if  you are loading a GENERIC POLYGON mesh
                                }
                                else
                                {
                                    //_BEGIN___ if  you are loading a  TRIMESH mesh
                                    std::vector<std::vector<vcg::Point3f> > polygonVect(1); // it is a vector of polygon loops
                                    polygonVect[0].resize(vertexesPerFace);
                                    std::vector<int> indexVVect(vertexesPerFace);
                                    std::vector<int> indexNVect(vertexesPerFace);
                                    std::vector<int> indexTVect(vertexesPerFace);
                                    std::vector<int> indexTriangulatedVect;

                                    for(int pi=0;pi<vertexesPerFace;++pi)
                                    {
                                        SplitToken(tokens[pi+1], indexVVect[pi],indexNVect[pi],indexTVect[pi], inputMask);
                                        if(QuadFlag) indexVVect[pi]++; // NOTE THAT THE STUPID QOBJ FORMAT IS ZERO INDEXED!!!!
                                        GoodObjIndex(indexVVect[pi],numVertices);
                                        GoodObjIndex(indexTVect[pi],oi.numTexCoords);
                                        polygonVect[0][pi].Import(m.vert[indexVVect[pi]].cP());
                                    }
                                    if(vertexesPerFace>3)
                                       oi.mask |= Mask::IOM_BITPOLYGONAL;

                                    if(vertexesPerFace<5)
                                        FanTessellator(polygonVect, indexTriangulatedVect);
                                    else
                                    {
#ifdef __gl_h_
                                        //qDebug("OK: using opengl tessellation for a polygon of %i verteces",vertexesPerFace);
                                        vcg::glu_tesselator::tesselate<vcg::Point3f>(polygonVect, indexTriangulatedVect);
                                        if(indexTriangulatedVect.size()==0)
                                          FanTessellator(polygonVect, indexTriangulatedVect);
#else
                                        //qDebug("Warning: using fan tessellation for a polygon of %i verteces",vertexesPerFace);
                                        FanTessellator(polygonVect, indexTriangulatedVect);
#endif
                                    }
                                    extraTriangles+=((indexTriangulatedVect.size()/3) -1);
#ifdef QT_VERSION
                                    if( int(indexTriangulatedVect.size()/3) != vertexesPerFace-2)
                                    {
                                        qDebug("Warning there is a degenerate poligon of %i verteces that was triangulated into %i triangles",vertexesPerFace,int(indexTriangulatedVect.size()/3));
                                        for(size_t qq=0;qq<polygonVect[0].size();++qq)
                                            qDebug("      (%f %f %f)",polygonVect[0][qq][0],polygonVect[0][qq][1],polygonVect[0][qq][2]);
                                        for(size_t qq=0;qq<tokens.size();++qq) qDebug("<%s>",tokens[qq].c_str());
                                    }
#endif
                                    //qDebug("Triangulated a face of %i vertexes into %i triangles",polygonVect[0].size(),indexTriangulatedVect.size());

                                    for(size_t pi=0;pi<indexTriangulatedVect.size();pi+=3)
                                    {
                                        ff.set(3);
                                        int locInd[3];
                                        for(int iii=0;iii<3;++iii)
                                        {
                                            locInd[iii]=indexTriangulatedVect[pi+iii];
                                            ff.v[iii]=indexVVect[ locInd[iii] ];
                                            ff.n[iii]=indexNVect[ locInd[iii] ];
                                            ff.t[iii]=indexTVect[ locInd[iii] ];
                                        }

                                        // Setting internal edges: only edges formed by consecutive edges are external.
                                        for(int iii=0;iii<3;++iii)
                                        {
                                            if( (locInd[iii]+1)%vertexesPerFace == locInd[(iii+1)%3]) ff.edge[iii]=false;
                                            else ff.edge[iii]=true;
                                        }

                                        if ( oi.mask & vcg::tri::io::Mask::IOM_WEDGTEXCOORD )
                                        { // verifying validity of texture coords indices
                                            bool invalid = false;
                                            for(int i=0;i<3;i++)
                                                if(!GoodObjIndex(ff.t[i],oi.numTexCoords))
                                                {
                                                    //return E_BAD_VERT_TEX_INDEX;
                                                    invalid = true;
                                                    break;
                                                }
                                                if (invalid) continue;
                                                ff.tInd=materials[currentMaterialIdx].index;
                                        }

                                        // verifying validity of vertex indices
                                        if ((ff.v[0] == ff.v[1]) || (ff.v[0] == ff.v[2]) || (ff.v[1] == ff.v[2])) {
                                            result = E_VERTICES_WITH_SAME_IDX_IN_FACE;
                                            extraTriangles--;
                                            continue;
                                        }

                                        {
                                            bool invalid = false;
                                            for(int i=0;i<3;i++)
                                                if(!GoodObjIndex(ff.v[i],numVertices))
                                                {
                                                    //return E_BAD_VERT_INDEX;
                                                    invalid = true;
                                                    break;
                                                }
                                            if (invalid) continue;
                                        }

                                        // assigning face normal
                                        if ( ( oi.mask & vcg::tri::io::Mask::IOM_WEDGNORMAL  ) ||
                                             ( oi.mask & vcg::tri::io::Mask::IOM_VERTNORMAL  ) )
                                        {   // verifying validity of vertex normal indices
                                            bool invalid = false;
                                            for(int i=0;i<3;i++)
                                                if(!GoodObjIndex(ff.n[i],numVNormals))
                                                {
                                                    //return E_BAD_VERT_NORMAL_INDEX;
                                                    invalid = true;
                                                    break;
                                                }
                                                if (invalid) continue;
                                        }

                                        // assigning face color
                                        if( oi.mask & vcg::tri::io::Mask::IOM_FACECOLOR) ff.c = currentColor;

                                        ++numTriangles;
                                        indexedFaces.push_back(ff);
                                    }

                                }
                            }
                            else if ((header.compare("mtllib")==0) && (tokens.size() > 1))	// material library
                            {
                                // obtain the name of the file containing materials library
                                std::string materialFileName = tokens[1];
                                if (!LoadMaterials( materialFileName.c_str(), materials, m.textures))
                                    result = E_MATERIAL_FILE_NOT_FOUND;
                            }
                            else if ((header.compare("usemtl")==0) && (tokens.size() > 1))	// material usage
                            {
                                std::string materialName = tokens[1];
                                bool found = false;
                                unsigned i = 0;
                                while (!found && (i < materials.size()))
                                {
                                    std::string currentMaterialName = materials[i].materialName;
                                    if (currentMaterialName == materialName)
                                    {
                                        currentMaterialIdx = i;
                                        Material &material = materials[currentMaterialIdx];
                                        Point3f diffuseColor = material.Kd;
                                        unsigned char r			= (unsigned char) (diffuseColor[0] * 255.0);
                                        unsigned char g			= (unsigned char) (diffuseColor[1] * 255.0);
                                        unsigned char b			= (unsigned char) (diffuseColor[2] * 255.0);
                                        unsigned char alpha = (unsigned char) (material.Tr  * 255.0);
                                        currentColor= Color4b(r, g, b, alpha);
                                        found = true;
                                    }
                                    ++i;
                                }

                                if (!found)
                                {
                                    currentMaterialIdx = 0;
                                    result = E_MATERIAL_NOT_FOUND;
                                }
                            }
                            // we simply ignore other situations
                        } // end for each line...
                    } // end while stream not eof
                    assert((numTriangles +numVertices) == numVerticesPlusFaces+extraTriangles);
                    vcg::tri::Allocator<OpenMeshType>::AddFaces(m,numTriangles);

                    // Add found edges
                    if (numEdges > 0)
                    {
                        vcg::tri::Allocator<OpenMeshType>::AddEdges(m,numEdges);

                        assert(m.edge.size() == size_t(m.en));

                        for(int i=0; i<numEdges; ++i)
                        {
                            ObjEdge &  e    = ev[i];
                            assert(e.v0 >= 0 && size_t(e.v0) < m.vert.size() &&
                                   e.v1 >= 0 && size_t(e.v1) < m.vert.size());
                            // TODO add proper handling of bad indices
                            m.edge[i].V(0) = &(m.vert[e.v0]);
                            m.edge[i].V(1) = &(m.vert[e.v1]);
                        }
                    }
                    //-------------------------------------------------------------------------------

                    // Now the final passes:
                    // First Pass to convert indexes into pointers for face to vert/norm/tex references
                    for(int i=0; i<numTriangles; ++i)
                    {
                        assert(m.face.size() == size_t(m.fn));
                        m.face[i].Alloc(indexedFaces[i].v.size()); // it does not do anything if it is a trimesh

                        for(unsigned int j=0;j<indexedFaces[i].v.size();++j)
                        {   
                           int vertInd = indexedFaces[i].v[j];
                           assert(vertInd >=0 && vertInd < m.vn);
                            m.face[i].V(j) = &(m.vert[indexedFaces[i].v[j]]);

                            if (((oi.mask & vcg::tri::io::Mask::IOM_WEDGTEXCOORD) != 0) && (HasPerWedgeTexCoord(m)))
                            {
                                ObjTexCoord t = texCoords[indexedFaces[i].t[j]];
                                m.face[i].WT(j).u() = t.u;
                                m.face[i].WT(j).v() = t.v;
                                m.face[i].WT(j).n() = indexedFaces[i].tInd;
                            }
                            if ( oi.mask & vcg::tri::io::Mask::IOM_VERTTEXCOORD ) {
                                ObjTexCoord t = texCoords[indexedFaces[i].t[j]];
                                m.face[i].V(j)->T().u() = t.u;
                                m.face[i].V(j)->T().v() = t.v;
                                m.face[i].V(j)->T().n() = indexedFaces[i].tInd;
                            }
                            if ( oi.mask & vcg::tri::io::Mask::IOM_WEDGNORMAL )
                            {
                                m.face[i].WN(j).Import(normals[indexedFaces[i].n[j]]);
                            }

                            if ( oi.mask & vcg::tri::io::Mask::IOM_VERTNORMAL )
                            {
                                m.face[i].V(j)->N().Import(normals[indexedFaces[i].n[j]]);
                            }

                            // set faux edge flags according to internals faces
                            if (indexedFaces[i].edge[j]) 
								m.face[i].SetF(j);
                            else 
                                m.face[i].ClearF(j);
                        }

                        if (HasPerFaceNormal(m))
                        {
                            if (((oi.mask & vcg::tri::io::Mask::IOM_FACECOLOR) != 0) && (HasPerFaceColor(m)))
                            {
                                m.face[i].C() = indexedFaces[i].c;
                            }

                            if (((oi.mask & vcg::tri::io::Mask::IOM_WEDGNORMAL) != 0) && (HasPerWedgeNormal(m)))
                            {
                                // face normal is computed as an average of wedge normals
                                m.face[i].N().Import(m.face[i].WN(0)+m.face[i].WN(1)+m.face[i].WN(2));
                            }
                            else
                            {
                                m.face[i].N().Import(TriangleNormal(m.face[i]).Normalize());
                            }
                        }
                    }
                    // final pass to manage the ZBrush PerVertex Color that are managed into comments
                    if(vertexColorVector.size()>0)
                    {
                        //	  if(vertexColorVector.size()!=m.vn){
                        //		qDebug("Warning Read %i vertices and %i vertex colors",m.vn,vertexColorVector.size());
                        //		qDebug("line count %i x 64 = %i",MRGBLineCount(), MRGBLineCount()*64);
                        //	  }
                        for(int i=0;i<m.vn;++i)
                        {
                            m.vert[i].C()=vertexColorVector[i];
                        }
                    }
                    stream.close();
                    return result;
                } // end of Open


                /*!
                * Read the next valid line and parses it into "tokens" (e.g. groups like 234/234/234), allowing
                * the tokens to be read one at a time. It read multiple lines  concatenating them if they end with '\'
                *  \param stream  The object providing the input stream
                *  \param tokens  The "tokens" in the next line
                */
                inline static void TokenizeNextLine(std::ifstream &stream, std::vector< std::string > &tokens, std::vector<Color4b> *colVec)
                {
                    if(stream.eof()) return;
                    std::string line;
                    do
                    {
                        std::getline(stream, line);
                        // We have to manage backspace terminated lines, 
                        // joining them together before parsing them
                        if(!line.empty() && line.back()==13) line.pop_back();
                        while(!line.empty() && line.back()=='\\') {
                          std::string tmpLine;
                          std::getline(stream, tmpLine);
                          if(tmpLine.back()==13) line.pop_back();
                          line.pop_back(); 
                          line.append(tmpLine);
                        }
                        const size_t len = line.length();
                        if((len > 0) && colVec && line[0] == '#')
                        {
                            // The following MRGB block contains ZBrush Vertex Color (Polypaint)
                            // and masking output as 4 hexadecimal values per vertex. The vertex color format is MMRRGGBB with up to 64 entries per MRGB line.
                            if((len >= 5) && line[1] == 'M' && line[2] == 'R' && line[3] == 'G' && line[4] == 'B')
                            { // Parsing the polycolor of ZBrush
                                MRGBLineCount()++;
                                char buf[3]="00";
                                Color4b cc(Color4b::Black);
                                for(size_t i=6;(i+7)<len;i+=8)
                                {
                                    for(size_t j=1;j<4;j++)
                                    {
                                        buf[0]=line[i+j*2+0];
                                        buf[1]=line[i+j*2+1];
                                        buf[2]=0;
                                        char *p;
                                        int val=strtoul(buf,&p,16);
                                        cc[j-1]= val;
                                    }
                                    colVec->push_back(cc);
                                }
                            }
                        }
                    }
                    while (( line.length()==0 || line[0] == '#') && !stream.eof());  // skip comments and empty lines

                    if ( (line.length() == 0)||(line[0] == '#') )  // can be true only on last line of file
                        return;

                    size_t from		= 0;
                    size_t to			= 0;
                    size_t length = line.size();

                    tokens.clear();
                    do
                    {
                        while (from!=length && (line[from]==' ' || line[from]=='\t' || line[from]=='\r') )
                            from++;
                        if(from!=length)
                        {
                            to = from+1;
                            while (to!=length && line[to]!=' ' && line[to] != '\t' && line[to]!='\r')
                                to++;
                            tokens.push_back(line.substr(from, to-from).c_str());
                            from = to;
                        }
                    }
                    while (from<length);
                } // end TokenizeNextLine

                // This function takes a token and, according to the mask, it returns the indexes of the involved vertex, normal and texcoord indexes.
                // Example. if the obj file has vertex texcoord (e.g. lines 'vt 0.444 0.5555')
                // when parsing  a line like
                // f 46/303 619/325 624/326 623/327
                // if in the mask you have specified to read wedge tex coord
                // for the first token it will return inside vId and tId the corresponding indexes 46 and 303 )                
                inline static void SplitToken(const std::string & token, int & vId, int & nId, int & tId, int mask)
                {
                    static const char delimiter = '/';

                    vId = nId = tId = 0;
                    if (token.empty()) return;

                    size_t firstSep  = token.find_first_of(delimiter);
                    size_t secondSep = (firstSep == std::string::npos) ? (std::string::npos) : (token.find_first_of(delimiter, firstSep + 1));

                    const bool hasPosition = true;
                    const bool hasTexcoord = (firstSep  != std::string::npos) && ((firstSep + 1) < secondSep);
                    const bool hasNormal   = (secondSep != std::string::npos) || (mask & Mask::IOM_WEDGNORMAL) || (mask & Mask::IOM_VERTNORMAL);

                    if (hasPosition) vId = atoi(token.substr(0, firstSep).c_str()) - 1;
                    if (hasTexcoord) tId = atoi(token.substr(firstSep + 1, secondSep - firstSep - 1).c_str()) - 1;
                    if (hasNormal)
                      nId = atoi(token.substr(secondSep + 1).c_str()) - 1;
                }


                /*!
                * Retrieves infos about kind of data stored into the file and fills a mask appropriately
                * \param filename The name of the file to open
                * \param mask     A mask which will be filled according to type of data found in the object
                * \param oi       A structure which will be filled with infos about the object to be opened
                */

                static bool LoadMask(const char * filename, Info &oi)
                {

                    std::ifstream stream(filename);
                    if (stream.fail())
                    {
                        stream.close();
                        return false;
                    }
                    // obtain length of file:
                    stream.seekg (0, std::ios::end);
                    int length = stream.tellg();
                    stream.seekg (0, std::ios::beg);

                    if (length == 0) return false;

                    bool bHasPerFaceColor		= false;
                    bool bHasNormals 				= false;
                    bool bHasPerVertexColor = false;

                    oi.numVertices=0;
                    oi.numEdges=0;
                    oi.numFaces=0;
                    oi.numTexCoords=0;
                    oi.numNormals=0;
                    int lineCount=0;
                    int totRead=0;
                    std::string line;
                    while (!stream.eof())
                    {
                        lineCount++;
                        std::getline(stream, line);
                        totRead+=line.size();
                        if(oi.cb && (lineCount%1000)==0)
                            (*oi.cb)( (int)(100.0*(float(totRead))/float(length)), "Loading mask...");
                        if(line.size()>2)
                        {
                            if(line[0]=='v')
                            {
                                if(line[1]==' ')
                                {
                                    oi.numVertices++;
                                    if(line.size()>=7)
                                        bHasPerVertexColor = true;
                                }
                                if(line[1]=='t') oi.numTexCoords++;
                                if(line[1]=='n') {
                                    oi.numNormals ++;
                                    bHasNormals = true;
                                }
                            }
                            else {
                                if((line[0]=='f') || (line[0]=='q')) oi.numFaces++;
                                else
                                    if (line[0]=='l') oi.numEdges++;
                                else
                                    if(line[0]=='u' && line[1]=='s') bHasPerFaceColor = true; // there is a usematerial so add per face color
                            }
                        }
                    }
                    oi.mask = 0;
                    if (oi.numTexCoords)
                    {
                        if (oi.numTexCoords==oi.numVertices)
                            oi.mask |= vcg::tri::io::Mask::IOM_VERTTEXCOORD;

                        oi.mask |= vcg::tri::io::Mask::IOM_WEDGTEXCOORD;
                        // Usually if you have tex coords you also have materials
                        oi.mask |= vcg::tri::io::Mask::IOM_FACECOLOR;
                    }
                    if(bHasPerFaceColor)		oi.mask |= vcg::tri::io::Mask::IOM_FACECOLOR;
                    if(bHasPerVertexColor)	oi.mask |= vcg::tri::io::Mask::IOM_VERTCOLOR;
                    if (bHasNormals) {
                        if (oi.numNormals == oi.numVertices)
                            oi.mask |= vcg::tri::io::Mask::IOM_VERTNORMAL;
                        else
                            oi.mask |= vcg::tri::io::Mask::IOM_WEDGNORMAL;
                    }
                    if (oi.numEdges)
                        oi.mask |= vcg::tri::io::Mask::IOM_EDGEINDEX;

                    stream.close();

                    return true;
                }

                static bool LoadMask(const char * filename, int &mask)
                {
                    Info oi;
                    bool ret=LoadMask(filename, oi);
                    mask= oi.mask;
                    return ret;
                }

                static bool LoadMaterials(const char * filename, std::vector<Material> &materials, std::vector<std::string> &textures)
                {
                    // assumes we are in the right directory

                    std::ifstream stream(filename);
                    if (stream.fail())
                        return false;

                    std::vector< std::string > tokens;
                    std::string	header;

                    materials.clear();
                    Material currentMaterial;
                    currentMaterial.index = (unsigned int)(-1);

                    bool first = true;
                    while (!stream.eof())
                    {
                        tokens.clear();
                        TokenizeNextLine(stream, tokens,0);

                        if (tokens.size() > 0)
                        {
                            header.clear();
                            header = tokens[0];

                            if (header.compare("newmtl")==0)
                            {
                                if (!first)
                                {
                                    materials.push_back(currentMaterial);
                                    currentMaterial = Material();
                                    currentMaterial.index = (unsigned int)(-1);
                                }
                                else
                                    first = false;
                                //strcpy(currentMaterial.name, tokens[1].c_str());
                                if(tokens.size() < 2)
                                    return false;
                                currentMaterial.materialName=tokens[1];
                            }
                            else if (header.compare("Ka")==0)
                            {
                                if (tokens.size() < 4)
                                    return false;
                                float r = (float) atof(tokens[1].c_str());
                                float g = (float) atof(tokens[2].c_str());
                                float b = (float) atof(tokens[3].c_str());

                                currentMaterial.Ka = Point3f(r, g, b);
                            }
                            else if (header.compare("Kd")==0)
                            {
                                if (tokens.size() < 4)
                                    return false;
                                float r = (float) atof(tokens[1].c_str());
                                float g = (float) atof(tokens[2].c_str());
                                float b = (float) atof(tokens[3].c_str());

                                currentMaterial.Kd = Point3f(r, g, b);
                            }
                            else if (header.compare("Ks")==0)
                            {
                                if (tokens.size() < 4)
                                    return false;
                                float r = (float) atof(tokens[1].c_str());
                                float g = (float) atof(tokens[2].c_str());
                                float b = (float) atof(tokens[3].c_str());

                                currentMaterial.Ks = Point3f(r, g, b);
                            }
                            else if (	(header.compare("d")==0) ||
                                (header.compare("Tr")==0)	)	// alpha
                            {
                                if (tokens.size() < 2)
                                    return false;
                                currentMaterial.Tr = (float) atof(tokens[1].c_str());
                            }
                            else if (header.compare("Ns")==0)  // shininess
                            {
                                if (tokens.size() < 2)
                                    return false;
                                currentMaterial.Ns = float(atoi(tokens[1].c_str()));
                            }
                            else if (header.compare("illum")==0)	// specular illumination on/off
                            {
                                if (tokens.size() < 2)
                                    return false;
                                int illumination = atoi(tokens[1].c_str());
                                //currentMaterial.bSpecular = (illumination == 2);
                                currentMaterial.illum = illumination;
                            }
                            else if( (header.compare("map_Kd")==0)	|| (header.compare("map_Ka")==0) ) // texture name
                            {
                                if (tokens.size() < 2)
                                    return false;
                                std::string textureName = tokens[1];
                                //strcpy(currentMaterial.textureFileName, textureName.c_str());
                                currentMaterial.map_Kd=textureName;

                                // adding texture name into textures vector (if not already present)
                                // avoid adding the same name twice
                                bool found = false;
                                unsigned int size = static_cast<unsigned int>(textures.size());
                                unsigned j = 0;
                                while (!found && (j < size))
                                {
                                    if (textureName.compare(textures[j])==0)
                                    {
                                        currentMaterial.index = (int)j;
                                        found = true;
                                    }
                                    ++j;
                                }
                                if (!found)
                                {
                                    textures.push_back(textureName);
                                    currentMaterial.index = (int)size;
                                }
                            }
                            // we simply ignore other situations
                        }
                    }
                    materials.push_back(currentMaterial);  // add last read material

                    stream.close();

                    return true;
                }

            }; // end class
        } // end Namespace tri
    } // end Namespace io
} // end Namespace vcg

#endif  // ndef __VCGLIB_IMPORT_OBJ