/*
 * Copyright (c) 2013-2016, Roland Bock
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 *   Redistributions in binary form must reproduce the above copyright notice, this
 *   list of conditions and the following disclaimer in the documentation and/or
 *   other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef SQLPP11_DYNAMIC_SELECT_COLUMN_LIST_H
#define SQLPP11_DYNAMIC_SELECT_COLUMN_LIST_H

#include <vector>
#include <string>
#include <sqlpp11/no_name.h>
#include <sqlpp11/named_interpretable.h>

namespace sqlpp
{
  template <typename Db>
  struct dynamic_select_column_list
  {
    using _names_t = std::vector<std::string>;
    std::vector<named_interpretable_t<Db>> _dynamic_columns;
    _names_t _dynamic_expression_names;

    template <typename Expr>
    void emplace_back(Expr expr)
    {
      _dynamic_expression_names.push_back(name_of<Expr>::template char_ptr<typename Db::_serializer_context_t>());
      _dynamic_columns.emplace_back(expr);
    }

    bool empty() const
    {
      return _dynamic_columns.empty();
    }

    auto size() -> size_t
    {
      return _dynamic_columns.size();
    }
  };

  template <>
  struct dynamic_select_column_list<void>
  {
    using _names_t = no_name_t;
    _names_t _dynamic_expression_names;

    static constexpr bool empty()
    {
      return true;
    }

    static constexpr auto size() -> size_t
    {
      return {};
    }
  };

  template <typename Context, typename Db>
  struct serializer_t<Context, dynamic_select_column_list<Db>>
  {
    using T = dynamic_select_column_list<Db>;

    static Context& _(const T& t, Context& context)
    {
      bool first = true;
      for (const auto column : t._dynamic_columns)
      {
        if (first)
        {
          first = false;
        }
        else
        {
          context << ',';
        }
        serialize(column, context);
      }
      return context;
    }
  };

  template <typename Context>
  struct serializer_t<Context, dynamic_select_column_list<void>>
  {
    using T = dynamic_select_column_list<void>;

    static Context& _(const T& /*unused*/, Context& context)
    {
      return context;
    }
  };
}  // namespace sqlpp

#endif
