src/variants/chess/pawn.cpp

   1 /*
   2   Copyright (c) 2007 Paolo Capriotti <p.capriotti@gmail.com>
   3             (c) 2007 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 #include "pawn.h"
  12 #include "queen.h"
  13 #include <core/behaviour.h>
  14 #include <core/move.h>
  15 #include <core/pathinfo.h>
  16 #include <core/state.h>
  17 #include <core/board.h>
  18 #include <core/taguacast.h>
  19
  20 namespace Chess {
  21
  22 Pawn::Pawn() { }
  23
  24 QString Pawn::name() const { return "pawn"; }
  25
  26 bool Pawn::canMove(const Piece& piece, const Piece& target,
  27                    Move& move, const IState* state) const {
  28   const IBehaviour* behaviour = state->behaviour();
  29   if (!behaviour) return false;
  30   bool enPassant = state->flags()->get("en_passant_square").value<Point>() == move.dst();
  31
  32   // moving
  33   if (target == Piece() && !enPassant) {
  34     if (move.delta() == behaviour->direction(piece.color())) {
  35       if (move.dst().y == state->rank(state->board()->size().y - 1, piece.color())) {
  36         setPromotion(move, Queen::self());
  37       }
  38       return true;
  39     }
  40
  41     if (move.src().y == state->rank(1, piece.color()) &&
  42         move.delta() == behaviour->direction(piece.color()) * 2 &&
  43         (state->board()->get(move.src() + behaviour->direction(piece.color())) == NULL ||
  44          *state->board()->get(move.src() + behaviour->direction(piece.color())) == Piece())) {
  45       move.setType("en_passant_trigger");
  46       return true;
  47     }
  48     else
  49       return false;
  50   }
  51
  52   // capturing
  53   else if (enPassant || target.color() != piece.color()) {
  54     if (move.delta().y == behaviour->direction(piece.color()).y &&
  55         abs(move.delta().x) == 1) {
  56       if (enPassant)
  57         move.setType("en_passant_capture");
  58       else if (move.dst().y == state->rank(state->board()->size().y - 1, piece.color())) {
  59         setPromotion(move, Queen::self());
  60       }
  61
  62       return true;
  63     }
  64   }
  65
  66   return false;
  67 }
  68
  69 void Pawn::setPromotion(Move& move, const IType* type) const {
  70   move.setType("promotion");
  71   // FIXME use variant data to set promotion type, like e.g.:
  72   // move.setPromotion(m_data.get("promotion-type").value<QObject*>())
  73   if (!move.promotion()) move.setPromotion(type);
  74 }
  75
  76 int Pawn::index() const { return 10; }
  77
  78 Pawn* Pawn::self() {
  79   static Pawn s_instance;
  80   return &s_instance;
  81 }
  82
  83 }