// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#include "readWRL.h"
#include <iostream>

template <typename Scalar, typename Index> IGL_INLINE bool igl::readWRL(const std::string wrl_file_name, std::vector<std::vector<Scalar>> &V, std::vector<std::vector<Index>> &F, std::vector<std::vector<Scalar>> &TexCoord, std::vector<std::vector<Index>> &TexCoordIndex) {
  using namespace std;
  FILE *wrl_file = fopen(wrl_file_name.c_str(), "r");
  if (NULL == wrl_file) {
    printf("IOError: %s could not be opened...", wrl_file_name.c_str());
    return false;
  }
  return readWRL(wrl_file, V, F, TexCoord, TexCoordIndex);
}

template <typename Scalar, typename Index> IGL_INLINE bool igl::readWRL(FILE *wrl_file, std::vector<std::vector<Scalar>> &V, std::vector<std::vector<Index>> &F, std::vector<std::vector<Scalar>> &TexCoord, std::vector<std::vector<Index>> &TexCoordIndex) {
  using namespace std;

  // Read lines until one of the needles occurs. Treat other lines as "comments"
  string needleVertices = string("point ["), needleFaces = string("coordIndex ["), needleTexCoords = string("point ["), needleTexCoordIndices = string("texCoordIndex [");
  bool foundVertices = false;
  while (true) {
    char line[1000];
    if (fgets(line, 1000, wrl_file) == NULL) {
      if (foundVertices) {
        break;
      } else {
        std::cerr << "readWRL, reached EOF without finding the needle" << std::endl;
        fclose(wrl_file);
        return false;
      }
    }
    string haystack(line);
    if (haystack.find(needleVertices) != string::npos && !foundVertices) { // read vertices in sets of 3
      foundVertices   = true;
      int floats_read = 3;
      while (floats_read == 3) {
        double x, y, z;
        floats_read = fscanf(wrl_file, " %lf %lf %lf,", &x, &y, &z);
        if (floats_read == 3) {
          vector<Scalar> point;
          point.resize(3);
          point[0] = x;
          point[1] = y;
          point[2] = z;
          V.push_back(point);
          // printf("(%g, %g, %g)\n",x,y,z);
        } else if (floats_read != 0) {
          printf("ERROR: unrecognized format...\n");
          return false;
        }
      }
    } else if (haystack.find(needleFaces) != string::npos) { // read faces
      int ints_read = 1;
      while (ints_read > 0) {
        // read new face indices (until hit -1)
        vector<Index> face;
        while (true) {
          // indices are 0-indexed
          int i;
          ints_read = fscanf(wrl_file, " %d,", &i);
          if (ints_read > 0) {
            if (i >= 0) {
              face.push_back(i);
            } else {
              F.push_back(face);
              break;
            }
          } else {
            break;
          }
        }
      }
    } else if (haystack.find(needleTexCoords) != string::npos) { // read texture coordinates
      // read points in sets of 2
      int floats_read = 2;
      while (floats_read == 2) {
        double x, y;
        floats_read = fscanf(wrl_file, " %lf %lf,", &x, &y);
        if (floats_read == 2) {
          vector<Scalar> point;
          point.resize(2);
          point[0] = x;
          point[1] = y;
          TexCoord.push_back(point);
          // printf("(%g, %g)\n",x,y);
        } else if (floats_read != 0) {
          printf("ERROR: unrecognized format...\n");
          return false;
        }
      }
    } else if (haystack.find(needleTexCoordIndices) != string::npos) { // read texCoordIndex
      int ints_read = 1;
      while (ints_read > 0) {
        // read new texture coordinate indices (until hit -1)
        vector<Index> texCoordIndex;
        while (true) {
          // indices are 0-indexed
          int i;
          ints_read = fscanf(wrl_file, " %d,", &i);
          if (ints_read > 0) {
            if (i >= 0) {
              texCoordIndex.push_back(i);
            } else {
              TexCoordIndex.push_back(texCoordIndex);
              break;
            }
          } else {
            break;
          }
        }
      }
    }
  }
  fclose(wrl_file);
  return true;
}

#ifdef IGL_STATIC_LIBRARY
// Explicit template instantiation
template bool igl::readWRL<double, int>(std::basic_string<char, std::char_traits<char>, std::allocator<char>>, std::vector<std::vector<double, std::allocator<double>>, std::allocator<std::vector<double, std::allocator<double>>>> &, std::vector<std::vector<int, std::allocator<int>>, std::allocator<std::vector<int, std::allocator<int>>>> &, std::vector<std::vector<double, std::allocator<double>>, std::allocator<std::vector<double, std::allocator<double>>>> &, std::vector<std::vector<int, std::allocator<int>>, std::allocator<std::vector<int, std::allocator<int>>>> &);
#endif