/* ========================================================================= *
 *                                                                           *
 *                               OpenMesh                                    *
 *           Copyright (c) 2001-2025, RWTH-Aachen University                 *
 *           Department of Computer Graphics and Multimedia                  *
 *                          All rights reserved.                             *
 *                            www.openmesh.org                               *
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 *---------------------------------------------------------------------------*
 * This file is part of OpenMesh.                                            *
 *---------------------------------------------------------------------------*
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 * modification, are permitted provided that the following conditions        *
 * are met:                                                                  *
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 *    this software without specific prior written permission.               *
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 *                                                                           *
 * ========================================================================= */




//== INCLUDES =================================================================

#include <fstream>
#include <OpenMesh/Core/System/omstream.hh>
#include <OpenMesh/Core/Utils/Endian.hh>
#include <OpenMesh/Core/IO/IOManager.hh>
#include <OpenMesh/Core/IO/BinaryHelper.hh>
#include <OpenMesh/Core/IO/writer/PLYWriter.hh>

#include <iostream>

//=== NAMESPACES ==============================================================


namespace OpenMesh {
namespace IO {


//=== INSTANCIATE =============================================================


// register the PLYLoader singleton with MeshLoader
_PLYWriter_  __PLYWriterInstance;
_PLYWriter_& PLYWriter() { return __PLYWriterInstance; }


//=== IMPLEMENTATION ==========================================================


_PLYWriter_::_PLYWriter_()
{
  IOManager().register_module(this);

  nameOfType_[Unsupported]  = "";
  nameOfType_[ValueTypeCHAR] = "char";
  nameOfType_[ValueTypeUCHAR] = nameOfType_[ValueTypeUINT8] = "uchar";
  nameOfType_[ValueTypeUSHORT] = "ushort";
  nameOfType_[ValueTypeSHORT]  = "short";
  nameOfType_[ValueTypeUINT]   = "uint";
  nameOfType_[ValueTypeINT]    = "int";
  nameOfType_[ValueTypeFLOAT32] = nameOfType_[ValueTypeFLOAT]  = "float";
  nameOfType_[ValueTypeDOUBLE] = "double";
}


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


bool
_PLYWriter_::
write(const std::string& _filename, BaseExporter& _be, const Options& _opt, std::streamsize _precision) const
{

  // open file
  std::ofstream out(_filename.c_str(), (_opt.check(Options::Binary) ? std::ios_base::binary | std::ios_base::out
                                                         : std::ios_base::out) );
  return write(out, _be, _opt, _precision);
}

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


bool
_PLYWriter_::
write(std::ostream& _os, BaseExporter& _be, const Options& _writeOptions, std::streamsize _precision) const
{

  options_ = _writeOptions;

  // check exporter features
  if ( !check( _be, options_ ) )
    return false;

  // check writer features
  if ( options_.check(Options::FaceNormal) ) {
    // Face normals are not supported
    // Uncheck these options and output message that
    // they are not written out even though they were requested
    options_.unset(Options::FaceNormal);
    omerr() << "[PLYWriter] : Warning: Face normals are not supported and thus not exported! " << std::endl;
  }



  if (!_os.good())
  {
    omerr() << "[PLYWriter] : cannot write to stream "
    << std::endl;
    return false;
  }

  if (!options_.check(Options::Binary))
    _os.precision(_precision);

  // write to file
  bool result = (options_.check(Options::Binary) ?
     write_binary(_os, _be, options_) :
     write_ascii(_os, _be, options_));

  return result;
}

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

// helper function for casting a property
template<typename T>
const PropertyT<T>* castProperty(const BaseProperty* _prop)
{
  return dynamic_cast< const PropertyT<T>* >(_prop);
}

//-----------------------------------------------------------------------------
std::vector<_PLYWriter_::CustomProperty> _PLYWriter_::writeCustomTypeHeader(std::ostream& _out, BaseKernel::const_prop_iterator _begin, BaseKernel::const_prop_iterator _end) const
{
  std::vector<CustomProperty> customProps;
  for (;_begin != _end; ++_begin)
  {
    BaseProperty* prop = *_begin;


    // check, if property is persistant
    if (!prop || !prop->persistent())
      continue;


    // identify type of property
    CustomProperty cProp(prop);
    size_t propSize = prop->element_size();
    switch (propSize)
    {
    case 1:
    {
      assert_compile(sizeof(char) == 1);
      //check, if prop is a char or unsigned char by dynamic_cast
      //char, unsigned char and signed char are 3 distinct types
      if (castProperty<signed char>(prop) != 0 || castProperty<char>(prop) != 0) //treat char as signed char
        cProp.type = ValueTypeCHAR;
      else if (castProperty<unsigned char>(prop) != 0)
        cProp.type = ValueTypeUCHAR;
      break;
    }
    case 2:
    {
      assert_compile (sizeof(short) == 2);
      if (castProperty<signed short>(prop) != 0)
        cProp.type = ValueTypeSHORT;
      else if (castProperty<unsigned short>(prop) != 0)
        cProp.type = ValueTypeUSHORT;
      break;
    }
    case 4:
    {
      assert_compile (sizeof(int) == 4);
      assert_compile (sizeof(float) == 4);
      if (castProperty<signed int>(prop) != 0)
        cProp.type = ValueTypeINT;
      else if (castProperty<unsigned int>(prop) != 0)
        cProp.type = ValueTypeUINT;
      else if (castProperty<float>(prop) != 0)
        cProp.type = ValueTypeFLOAT;
      break;

    }
    case 8:
      assert_compile (sizeof(double) == 8);
      if (castProperty<double>(prop) != 0)
        cProp.type = ValueTypeDOUBLE;
      break;
    default:
      break;
    }

    if (cProp.type != Unsupported)
    {
      // property type was identified and it is persistant, write into header
      customProps.push_back(cProp);
      _out << "property " << nameOfType_[cProp.type] << " " << cProp.property->name() << "\n";
    }
  }
  return customProps;
}

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

template<bool binary>
void _PLYWriter_::write_customProp(std::ostream& _out, const CustomProperty& _prop, size_t _index) const
{
  if (_prop.type == ValueTypeCHAR)
    writeProxy(_prop.type,_out, castProperty<signed char>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeUCHAR || _prop.type == ValueTypeUINT8)
    writeProxy(_prop.type,_out, castProperty<unsigned char>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeSHORT)
    writeProxy(_prop.type,_out, castProperty<signed short>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeUSHORT)
    writeProxy(_prop.type,_out, castProperty<unsigned short>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeUINT)
    writeProxy(_prop.type,_out, castProperty<unsigned int>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeINT || _prop.type == ValueTypeINT32)
    writeProxy(_prop.type,_out, castProperty<signed int>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeFLOAT || _prop.type == ValueTypeFLOAT32)
    writeProxy(_prop.type,_out, castProperty<float>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
  else if (_prop.type == ValueTypeDOUBLE)
    writeProxy(_prop.type,_out, castProperty<double>(_prop.property)->data()[_index], OpenMesh::GenProg::Bool2Type<binary>());
}


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



void _PLYWriter_::write_header(std::ostream& _out, BaseExporter& _be, Options& _opt, std::vector<CustomProperty>& _ovProps, std::vector<CustomProperty>& _ofProps) const {
  //writing header
  _out << "ply" << '\n';

  if (_opt.is_binary()) {
    _out << "format ";
    if ( options_.check(Options::MSB) )
      _out << "binary_big_endian ";
    else
      _out << "binary_little_endian ";
    _out << "1.0" << '\n';
  } else
    _out << "format ascii 1.0" << '\n';

  _out << "element vertex " << _be.n_vertices() << '\n';

  _out << "property float x" << '\n';
  _out << "property float y" << '\n';
  _out << "property float z" << '\n';

  if ( _opt.vertex_has_normal() ){
    _out << "property float nx" << '\n';
    _out << "property float ny" << '\n';
    _out << "property float nz" << '\n';
  }

  if ( _opt.vertex_has_texcoord() ){
    if ( _opt.use_st_coordinates() ){
      _out << "property float s" << '\n';
      _out << "property float t" << '\n';
    } else {
      _out << "property float u" << '\n';
      _out << "property float v" << '\n';
    }
  }

  if ( _opt.vertex_has_color() ){
    if ( _opt.color_is_float() ) {
      _out << "property float red" << '\n';
      _out << "property float green" << '\n';
      _out << "property float blue" << '\n';

      if ( _opt.color_has_alpha() )
        _out << "property float alpha" << '\n';
    } else {
      _out << "property uchar red" << '\n';
      _out << "property uchar green" << '\n';
      _out << "property uchar blue" << '\n';

      if ( _opt.color_has_alpha() )
        _out << "property uchar alpha" << '\n';
    }
  }

  _ovProps = writeCustomTypeHeader(_out, _be.kernel()->vprops_begin(), _be.kernel()->vprops_end());

  _out << "element face " << _be.n_faces() << '\n';
  _out << "property list uchar int vertex_indices" << '\n';

  if ( _opt.face_has_color() ){
    if ( _opt.color_is_float() ) {
      _out << "property float red" << '\n';
      _out << "property float green" << '\n';
      _out << "property float blue" << '\n';

      if ( _opt.color_has_alpha() )
        _out << "property float alpha" << '\n';
    } else {
      _out << "property uchar red" << '\n';
      _out << "property uchar green" << '\n';
      _out << "property uchar blue" << '\n';

      if ( _opt.color_has_alpha() )
        _out << "property uchar alpha" << '\n';
    }
  }

  _ofProps = writeCustomTypeHeader(_out, _be.kernel()->fprops_begin(), _be.kernel()->fprops_end());

  _out << "end_header" << '\n';
}


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


bool
_PLYWriter_::
write_ascii(std::ostream& _out, BaseExporter& _be, Options _opt) const
{
  
  unsigned int i, nV, nF;
  Vec3f v, n;
  OpenMesh::Vec3ui c;
  OpenMesh::Vec4ui cA;
  OpenMesh::Vec3f cf;
  OpenMesh::Vec4f cAf;
  OpenMesh::Vec2f t;
  VertexHandle vh;
  FaceHandle fh;
  std::vector<VertexHandle> vhandles;

  std::vector<CustomProperty> vProps;
  std::vector<CustomProperty> fProps;

  write_header(_out, _be, _opt, vProps, fProps);

  if (_opt.color_is_float())
    _out << std::fixed;

  // vertex data (point, normals, colors, texcoords)
  for (i=0, nV=int(_be.n_vertices()); i<nV; ++i)
  {
    vh = VertexHandle(i);
    v  = _be.point(vh);

    //Vertex
    _out << v[0] << " " << v[1] << " " << v[2];

    // Vertex Normals
    if ( _opt.vertex_has_normal() ){
      n = _be.normal(vh);
      _out << " " << n[0] << " " << n[1] << " " << n[2];
    }

    // Vertex TexCoords
    if ( _opt.vertex_has_texcoord() ) {
    	t = _be.texcoord(vh);
    	_out << " " << t[0] << " " << t[1];
    }

    // VertexColor
    if ( _opt.vertex_has_color() ) {
      //with alpha
      if ( _opt.color_has_alpha() ){
        if (_opt.color_is_float()) {
          cAf = _be.colorAf(vh);
          _out << " " << cAf;
        } else {
          cA  = _be.colorAi(vh);
          _out << " " << cA;
        }
      }else{
        //without alpha
        if (_opt.color_is_float()) {
          cf = _be.colorf(vh);
          _out << " " << cf;
        } else {
          c  = _be.colori(vh);
          _out << " " << c;
        }
      }
    }


    // write custom properties for vertices
    for (std::vector<CustomProperty>::iterator iter = vProps.begin(); iter < vProps.end(); ++iter)
      write_customProp<false>(_out,*iter,i);

    _out << "\n";
  }

  // faces (indices starting at 0)
  for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
  {
    fh = FaceHandle(i);

    // write vertex indices per face
    nV = _be.get_vhandles(fh, vhandles);
    _out << nV;
    for (size_t j=0; j<vhandles.size(); ++j)
      _out << " " << vhandles[j].idx();

    // FaceColor
    if ( _opt.face_has_color() ) {
      //with alpha
      if ( _opt.color_has_alpha() ){
        if (_opt.color_is_float()) {
          cAf = _be.colorAf(fh);
          _out << " " << cAf;
        } else {
          cA  = _be.colorAi(fh);
          _out << " " << cA;
        }
      }else{
        //without alpha
        if (_opt.color_is_float()) {
          cf = _be.colorf(fh);
          _out << " " << cf;
        } else {
          c  = _be.colori(fh);
          _out << " " << c;
        }
      }
    }

    // write custom props
    for (std::vector<CustomProperty>::iterator iter = fProps.begin(); iter < fProps.end(); ++iter)
      write_customProp<false>(_out,*iter,i);
    _out << "\n";
  }


  return true;
}


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

void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, int value) const {

  uint32_t tmp32;
  uint8_t tmp8;

  switch (_type) {
    case ValueTypeINT:
    case ValueTypeINT32:
      tmp32 = value;
      store(_out, tmp32, options_.check(Options::MSB) );
      break;
//     case ValueTypeUINT8:
default :
      tmp8 = value;
      store(_out, tmp8, options_.check(Options::MSB) );
      break;
//     default :
//       std::cerr << "unsupported conversion type to int: " << _type << std::endl;
//       break;
  }
}

void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, unsigned int value) const {

  uint32_t tmp32;
  uint8_t tmp8;

  switch (_type) {
    case ValueTypeINT:
    case ValueTypeINT32:
      tmp32 = value;
      store(_out, tmp32, options_.check(Options::MSB) );
      break;
//     case ValueTypeUINT8:
default :
      tmp8 = value;
      store(_out, tmp8, options_.check(Options::MSB) );
      break;
//     default :
//       std::cerr << "unsupported conversion type to int: " << _type << std::endl;
//       break;
  }
}

void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, float value) const {

  float32_t tmp;

  switch (_type) {
    case ValueTypeFLOAT32:
    case ValueTypeFLOAT:
      tmp = value;
      store( _out , tmp, options_.check(Options::MSB) );
      break;
    default :
      std::cerr << "unsupported conversion type to float: " << _type << std::endl;
      break;
  }
}

void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, double value) const {

  float64_t tmp;

  switch (_type) {
    case ValueTypeDOUBLE:
      tmp = value;
      store( _out , tmp, options_.check(Options::MSB) );
      break;
    default :
      std::cerr << "unsupported conversion type to float: " << _type << std::endl;
      break;
  }
}

void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, signed char value) const{

  int8_t tmp;

  switch (_type) {
  case ValueTypeCHAR:
    tmp = value;
    store(_out, tmp, options_.check(Options::MSB) );
    break;
  default :
    std::cerr << "unsupported conversion type to int: " << _type << std::endl;
    break;
  }
}
void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, unsigned char value) const{

  uint8_t tmp;

  switch (_type) {
  case ValueTypeUCHAR:
    tmp = value;
    store(_out, tmp, options_.check(Options::MSB) );
    break;
  default :
    std::cerr << "unsupported conversion type to int: " << _type << std::endl;
    break;
  }
}
void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, short value) const{

  int16_t tmp;

  switch (_type) {
  case ValueTypeSHORT:
    tmp = value;
    store(_out, tmp, options_.check(Options::MSB) );
    break;
  default :
    std::cerr << "unsupported conversion type to int: " << _type << std::endl;
    break;
  }
}
void _PLYWriter_::writeValue(ValueType _type, std::ostream& _out, unsigned short value) const{

  uint16_t tmp;

  switch (_type) {
  case ValueTypeUSHORT:
    tmp = value;
    store(_out, tmp, options_.check(Options::MSB) );
    break;
  default :
    std::cerr << "unsupported conversion type to int: " << _type << std::endl;
    break;
  }
}

bool
_PLYWriter_::
write_binary(std::ostream& _out, BaseExporter& _be, Options _opt) const
{
  
  unsigned int i, nV, nF;
  Vec3f v, n;
  Vec2f t;
  OpenMesh::Vec4uc c;
  OpenMesh::Vec4f cf;
  VertexHandle vh;
  FaceHandle fh;
  std::vector<VertexHandle> vhandles;

  // vProps and fProps will be empty, until custom properties are supported by the binary writer
  std::vector<CustomProperty> vProps;
  std::vector<CustomProperty> fProps;

  write_header(_out, _be, _opt, vProps, fProps);

  // vertex data (point, normals, texcoords)
  for (i=0, nV=int(_be.n_vertices()); i<nV; ++i)
  {
    vh = VertexHandle(i);
    v  = _be.point(vh);

    //vertex
    writeValue(ValueTypeFLOAT, _out, v[0]);
    writeValue(ValueTypeFLOAT, _out, v[1]);
    writeValue(ValueTypeFLOAT, _out, v[2]);

    // Vertex Normal
    if ( _opt.vertex_has_normal() ){
      n = _be.normal(vh);
      writeValue(ValueTypeFLOAT, _out, n[0]);
      writeValue(ValueTypeFLOAT, _out, n[1]);
      writeValue(ValueTypeFLOAT, _out, n[2]);
    }

    // Vertex TexCoords
    if ( _opt.vertex_has_texcoord() ) {
    	t = _be.texcoord(vh);
    	writeValue(ValueTypeFLOAT, _out, t[0]);
    	writeValue(ValueTypeFLOAT, _out, t[1]);
    }

    // vertex color
    if ( _opt.vertex_has_color() ) {
        if ( _opt.color_is_float() ) {
          cf  = _be.colorAf(vh);
          writeValue(ValueTypeFLOAT, _out, cf[0]);
          writeValue(ValueTypeFLOAT, _out, cf[1]);
          writeValue(ValueTypeFLOAT, _out, cf[2]);

          if ( _opt.color_has_alpha() )
            writeValue(ValueTypeFLOAT, _out, cf[3]);
        } else {
          c  = _be.colorA(vh);
          writeValue(ValueTypeUCHAR, _out, (int)c[0]);
          writeValue(ValueTypeUCHAR, _out, (int)c[1]);
          writeValue(ValueTypeUCHAR, _out, (int)c[2]);

          if ( _opt.color_has_alpha() )
            writeValue(ValueTypeUCHAR, _out, (int)c[3]);
        }
    }

    for (std::vector<CustomProperty>::iterator iter = vProps.begin(); iter < vProps.end(); ++iter)
      write_customProp<true>(_out,*iter,i);
  }


  for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
  {
    fh = FaceHandle(i);

    //face
    nV = _be.get_vhandles(fh, vhandles);
    writeValue(ValueTypeUINT8, _out, nV);
    for (size_t j=0; j<vhandles.size(); ++j)
      writeValue(ValueTypeINT32, _out, vhandles[j].idx() );

    // face color
    if ( _opt.face_has_color() ) {
        if ( _opt.color_is_float() ) {
          cf  = _be.colorAf(fh);
          writeValue(ValueTypeFLOAT, _out, cf[0]);
          writeValue(ValueTypeFLOAT, _out, cf[1]);
          writeValue(ValueTypeFLOAT, _out, cf[2]);

          if ( _opt.color_has_alpha() )
            writeValue(ValueTypeFLOAT, _out, cf[3]);
        } else {
          c  = _be.colorA(fh);
          writeValue(ValueTypeUCHAR, _out, (int)c[0]);
          writeValue(ValueTypeUCHAR, _out, (int)c[1]);
          writeValue(ValueTypeUCHAR, _out, (int)c[2]);

          if ( _opt.color_has_alpha() )
            writeValue(ValueTypeUCHAR, _out, (int)c[3]);
        }
    }

    for (std::vector<CustomProperty>::iterator iter = fProps.begin(); iter < fProps.end(); ++iter)
      write_customProp<true>(_out,*iter,i);
  }

  return true;
}

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


size_t
_PLYWriter_::
binary_size(BaseExporter& _be, const Options& _writeOptions) const
{
  size_t header(0);
  size_t data(0);
  size_t _3floats(3*sizeof(float));
  size_t _3ui(3*sizeof(unsigned int));
  size_t _4ui(4*sizeof(unsigned int));

  if ( !_writeOptions.is_binary() )
    return 0;
  else
  {

    size_t _3longs(3*sizeof(long));

    header += 11;                             // 'OFF BINARY\n'
    header += _3longs;                        // #V #F #E
    data   += _be.n_vertices() * _3floats;    // vertex data
  }

  if ( _writeOptions.vertex_has_normal() && _be.has_vertex_normals() )
  {
    header += 1; // N
    data   += _be.n_vertices() * _3floats;
  }

  if ( _writeOptions.vertex_has_color() && _be.has_vertex_colors() )
  {
    header += 1; // C
    data   += _be.n_vertices() * _3floats;
  }

  if ( _writeOptions.vertex_has_texcoord() && _be.has_vertex_texcoords() )
  {
    size_t _2floats(2*sizeof(float));
    header += 2; // ST
    data   += _be.n_vertices() * _2floats;
  }

  // topology
  if (_be.is_triangle_mesh())
  {
    data += _be.n_faces() * _4ui;
  }
  else
  {
    unsigned int i, nF;
    std::vector<VertexHandle> vhandles;

    for (i=0, nF=int(_be.n_faces()); i<nF; ++i)
    {
      data += _be.get_vhandles(FaceHandle(i), vhandles) * sizeof(unsigned int);

    }
  }

  // face colors
  if ( _writeOptions.face_has_color() && _be.has_face_colors() ){
    if ( _writeOptions.color_has_alpha() )
      data += _be.n_faces() * _4ui;
    else
      data += _be.n_faces() * _3ui;
  }

  return header+data;
}


//=============================================================================
} // namespace IO
} // namespace OpenMesh
//=============================================================================