// Convert from OFF format to Wavefront (.obj) format.

#include <CGAL/IO/Verbose_ostream.h>
#include <CGAL/IO/OBJ.h>
#include <CGAL/IO/OFF.h>

#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <fstream>

using namespace std;

bool  verbose  = false;

// main function with standard unix commandline arguments
// ------------------------------------------------------
int main( int argc, char **argv)
{
  int n = 0; // number of filenames
  char *filename[2];
  bool help = false;
  for (int i = 1; i < argc; i++) { // check commandline options
    if ( strcmp( "-v", argv[i]) == 0)
      verbose = true;
    else if ( (strcmp( "-h", argv[i]) == 0) ||
              (strcmp( "-help", argv[i]) == 0))
      help = true;
    else if ( n < 2 ) {
      filename[ n++] = argv[i];
    } else {
      ++n;
      break;
    }
  }
  if ((n > 2) || help) {
    if ( ! help)
      cerr << "Error: in parameter list" << endl;
    cerr << "Usage: " << argv[0] << " [<options>] [<infile> [<outfile>]]"
         << endl;
    cerr << "       convert a CGAL object (OFF) to Wavefront obj format."
         << endl;
    cerr << "       -v      verbose." << endl;
    exit( ! help);
  }

  CGAL::Verbose_ostream vout( verbose);
  vout << argv[0] << ": verbosity on." << endl;

  const char*  iname = "cin";
  istream*     p_in  = &cin;
  ifstream     in;
  if ( n > 0) {
    in.open( filename[0]);
    p_in = &in;
    iname = filename[0];
  }
  if ( !*p_in) {
    cerr << argv[0] << ": error: cannot open file '"<< iname
                    << "' for reading." <<endl;
    exit( 1);
  }

  const char*  oname = "cout";
  ostream*     p_out = &cout;
  ofstream     out;
  if ( n > 1) {
    out.open( filename[1]);
    p_out = &out;
    oname = filename[1];
  }
  if ( !*p_out) {
    cerr << argv[0] << ": error: cannot open file '"<< oname
                    << "' for writing." <<endl;
    exit( 1);
  }

  vout << "CGAL::generic_copy_OFF( " << iname << ", " << oname
       << ") ...." << endl;
  CGAL::File_writer_wavefront  writer;
  CGAL::generic_copy_OFF( *p_in, *p_out, writer);
  vout << "    .... done." << endl;

  if ( !*p_in) {
    cerr << argv[0] << " read error: while reading file '"<< iname << "'."
                    << endl;
    exit( 1);
  }
  if ( !*p_out) {
    cerr << argv[0] <<" write error: while writing file '"<< oname << "'."
                   << endl;
    exit( 1);
  }

  return 0;
}
// EOF //
