/*  FileParser.cpp
 */

#include "FileParser.h"

/*

int main()
{
  string buffer;

  FileParser fp ( "sample.csv" );
  
 
  while ( fp.NextField( buffer ) )
      cout << buffer << endl;

  return 0;
 
}

*/

/* Constructor for FileParser class
 * param: string object containing filename 
 *
 */

FileParser::FileParser(string input_file)
{
  input = new ifstream( input_file.c_str() ); // initialize file stream
 
  if ( input->is_open() == false ) {  // error checking
	cerr << "The input file cannot be opened.\n";
	exit(1);
  }

  getline(*input,line_buffer); // get first line of input from *input
                               // and store in line_buffer member
  
}


/* Nextfield method
 * Gets next comma-separated field from the input stream
 * and puts it in string parameter field_buffer
 *
 */

int FileParser::NextField(string & field_buffer)
{
  unsigned int end;

  end = line_buffer.find(",");  // get position of next comma  
  

  if ( end != line_buffer.npos ) {  // if comma exists in line_buffer
    field_buffer = line_buffer.substr(0, end);  // this is the output field
    line_buffer = line_buffer.substr(end+1, line_buffer.size() ); //
 // shrink line_buffer
    return 1;
  } else {  // no more commas
    field_buffer = line_buffer;  // output remaining chars to end-of-line
    if (*input) {      // check for end of file stream
      getline(*input,line_buffer);
      return 1;
    }
    else
      return 0;
  }
  
  
}