src/serverreference.h

   1 /*
   2   Copyright (c) 2006 Paolo Capriotti <p.capriotti@sns.it>
   3             (c) 2006 Maurizio Monge <maurizio.monge@kdemail.net>
   4
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2 of the License, or
   8   (at your option) any later version.
   9 */
  10
  11 #ifndef CHESSREFERENCE_H
  12 #define CHESSREFERENCE_H
  13
  14 #include <boost/shared_ptr.hpp>
  15 #include "serverinfo.h"
  16
  17 template <typename Pos>
  18 struct ComparePosition {
  19   static bool apply(const Pos& chessPos, const Pos& pos) {
  20     return static_cast<const ChessPosition&>(chessPos) == pos;
  21   }
  22 };
  23
  24 /**
  25   * @brief Common base for ServerReference specializations.
  26   */
  27 template <typename Pos>
  28 struct ServerReferenceBase {
  29   typedef Pos Position;
  30
  31   class InfoVisitor : public boost::static_visitor<bool> {
  32     const Position& m_position;
  33   public:
  34     InfoVisitor(const Position& position)
  35     : m_position(position) { }
  36     bool operator()(const ChessServerInfo<Pos>& info) const {
  37       return ComparePosition<Pos>::apply(
  38         *info.position,
  39         m_position);
  40     }
  41     bool operator()(const PoolServerInfo<Pos>&) const {
  42       return true; // FIXME
  43     }
  44   };
  45
  46   /**
  47     * Compare a position with a @a ChessPosition. Used to check locally
  48     * computed positions against server provided positions.
  49     */
  50   static bool checkPosition(const Position& pos, const ChessPosition& serverPos) {
  51     return serverPos == pos;
  52   }
  53
  54   /**
  55     * Retrieve a position shared pointer from a @a ChessPosition
  56     * pointer. Used to retrieve variant specific position
  57     * information from @a style12.position
  58     */
  59   static boost::shared_ptr<Position> getPosition(
  60               const boost::shared_ptr<ChessPosition>& pos) {
  61     return boost::shared_ptr<Position>(
  62       new Position(*pos));
  63   }
  64
  65
  66   /**
  67     * Compare a position with partial information contained in another position.
  68     */
  69   static bool checkPartialPosition(const Position& pos, const typename ServerInfo<Position>::type& server) {
  70     return boost::apply_visitor(InfoVisitor(pos), server);
  71   }
  72 };
  73
  74 /**
  75   * @brief ServerReference is used whenever information coming from
  76   *        the server has to be compared with variant specific structures.
  77   */
  78 template <typename Pos>
  79 struct ServerReference : public ServerReferenceBase<Pos> { };
  80
  81 template <>
  82 struct ServerReference<ChessPosition>
  83 : public ServerReferenceBase<ChessPosition> {
  84   static boost::shared_ptr<ChessPosition> getPosition(
  85       const boost::shared_ptr<ChessPosition>& pos) {
  86     return pos;
  87   }
  88 };
  89
  90 #endif // CHESSREFERENCE_H