resultSet.hpp

/*
  ANCH Framework: ANother C++ Hack is a C++ framework based on C++11 standard
  Copyright (C) 2012 Vincent Lachenal
 
  This file is part of ANCH Framework.
 
  ANCH Framework is free software: you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
 
  ANCH Framework is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Lesser General Public License for more details.
 
  You should have received a copy of the GNU Lesser General Public License
  along with ANCH Framework.  If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
 
#include <string>
#include <vector>
#include <sstream>
#include <map>
#include <optional>
 
#include "sql/sqlException.hpp"
 
#include "date/dateFormatter.hpp"
#include "sql/types/date.hpp"
#include "sql/types/time.hpp"
#include "sql/types/timestamp.hpp"
 
 
namespace anch {
  namespace sql {

    class ResultSet {
 
      // Attributes +
    protected:
      std::map<std::string, std::size_t> _fields;
      // Attributes -
 
      // Constructors +
    public:
      ResultSet() noexcept;
      // Constructors -
 
      // Destructor +
    public:
      virtual ~ResultSet() noexcept;
      // Destructor -
 
      // Methods +
      template<typename T>
      bool get(std::size_t idx, T& out);

      template<typename T>
      bool get(const std::string field, T& out) {
        auto search = _fields.find(field);
        if(search == _fields.end()) {
          std::ostringstream msg;
          msg << "Field " << field << " does not exist in result set. "
            "Available fields are [";
          for(auto iter = _fields.cbegin() ; iter != _fields.cend() ; ++iter) {
            if(iter != _fields.cbegin()) {
              msg << ',';
            }
            msg << iter->first;
          }
          msg << ']';
          throw SqlException(msg.str());
        }
        return get<T>(search->second, out);
      }

      template<typename T>
      std::optional<T> get(std::size_t idx);

      template<typename T>
      const std::optional<T> get(const std::string field) {
        auto search = _fields.find(field);
        if(search == _fields.end()) {
          std::ostringstream msg;
          msg << "Field " << field << " does not exist in result set. "
            "Available fields are [";
          for(auto iter = _fields.cbegin() ; iter != _fields.cend() ; ++iter) {
            if(iter != _fields.cbegin()) {
              msg << ',';
            }
            msg << iter->first;
          }
          msg << ']';
          throw SqlException(msg.str());
        }
        return get<T>(search->second);
      }

      virtual bool next() = 0;
 
    protected:
      virtual bool getValue(std::size_t idx, std::string& out) = 0;

      virtual std::optional<std::string> getValue(std::size_t idx) = 0;

      virtual const anch::date::DateFormatter& getDateFormatter() = 0;

      virtual const anch::date::DateFormatter& getTimeFormatter() = 0;

      virtual const anch::date::DateFormatter& getTimestampFormatter() = 0;

      const anch::date::DateFormatter& getDefaultDateFormatter();

      const anch::date::DateFormatter& getDefaultTimeFormatter();

      const anch::date::DateFormatter& getDefaultTimestampFormatter();
      // Methods -
 
    };
 
  }
}