Parsing Pgn File and getting progress (header file) solved

#ifndef PGNGAMESEXTRACTOR_HPP
#define PGNGAMESEXTRACTOR_HPP

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

#include <boost/spirit/include/phoenix.hpp>
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/repository/include/qi_iter_pos.hpp>

namespace loloof64 {

namespace phx = boost::phoenix;
namespace qi = boost::spirit::qi;
namespace qr = boost::spirit::repository::qi;

enum result_t { white_won, black_won, draw, undecided };

struct pgn_tag {
    std::string key;
    std::string value;
};

struct game_move {
    unsigned move_number;
    std::string white_move;
    std::string black_move;
    result_t result;
};

struct pgn_game {
    std::vector<pgn_tag> header;
    std::vector<game_move> moves;
};

/**
 * Got this class there : http://marko-editor.com/articles/position_tracking/
 */
template<typename Iterator>
struct CurrentPos {
  CurrentPos() {
    save_start_pos = qi::omit[qr::iter_pos[
            phx::bind(&CurrentPos::setStartPos, this, qi::_1)]];
    current_pos = qr::iter_pos[
            qi::_val = phx::bind(&CurrentPos::getCurrentPos, this, qi::_1)];
  }

  qi::rule<Iterator> save_start_pos;
  qi::rule<Iterator, std::size_t()> current_pos;

private:
  void setStartPos(const Iterator &iterator) {
    start_pos_ = iterator;
  }

  std::size_t getCurrentPos(const Iterator &iterator) {
    return std::distance(start_pos_, iterator);
  }

  Iterator start_pos_;
};

class PgnGamesExtractor {
  public:
    PgnGamesExtractor(std::string const &inputFilePath);
    /*
    Constructor may throw PgnParsingException (if bad pgn format) and InputFileException (if missing file)
    */
    std::vector<pgn_game> getGames() const { return games; }
    virtual ~PgnGamesExtractor();

  protected:
  private:
    std::vector<pgn_game> games;
    void parseInput(std::string const &inputFilePath);
};

class PgnParsingException : public virtual std::runtime_error {
  public:
    PgnParsingException(std::string message) : std::runtime_error(message) {}
};

class InputFileException : public virtual std::runtime_error {
  public:
    InputFileException(std::string message) : std::runtime_error(message) {}
};


}

#endif // PGNGAMESEXTRACTOR_HPP