/* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Stockfish 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ //// //// Includes //// #include #include "move.h" #include "piece.h" #include "position.h" //// //// Functions //// /// move_from_string() takes a position and a string as input, and attempts to /// convert the string to a move, using simple coordinate notation (g1f3, /// a7a8q, etc.). In order to correctly parse en passant captures and castling /// moves, we need the position. This function is not robust, and expects that /// the input move is legal and correctly formatted. Move move_from_string(const Position& pos, const std::string& str) { Square from, to; Piece piece; Color us = pos.side_to_move(); if (str.length() < 4) return MOVE_NONE; // Read the from and to squares from = square_from_string(str.substr(0, 2)); to = square_from_string(str.substr(2, 4)); // Find the moving piece piece = pos.piece_on(from); // If the string has more than 4 characters, try to interpret the 5th // character as a promotion if (type_of_piece(piece) == PAWN && str.length() > 4) { switch (tolower(str[4])) { case 'n': return make_promotion_move(from, to, KNIGHT); case 'b': return make_promotion_move(from, to, BISHOP); case 'r': return make_promotion_move(from, to, ROOK); case 'q': return make_promotion_move(from, to, QUEEN); } } if (piece == piece_of_color_and_type(us, KING)) { // Is this a castling move? A king move is assumed to be a castling // move if the destination square is occupied by a friendly rook, or // if the distance between the source and destination squares is more // than 1. if (pos.piece_on(to) == piece_of_color_and_type(us, ROOK)) return make_castle_move(from, to); else if (square_distance(from, to) > 1) { // This is a castling move, but we have to translate it to the // internal "king captures rook" representation. SquareDelta delta = (to > from ? DELTA_E : DELTA_W); Square s = from + delta; while (relative_rank(us, s) == RANK_1 && pos.piece_on(s) != piece_of_color_and_type(us, ROOK)) s += delta; return (relative_rank(us, s) == RANK_1 ? make_castle_move(from, s) : MOVE_NONE); } } else if (piece == piece_of_color_and_type(us, PAWN)) { // En passant move? We assume that a pawn move is an en passant move // without further testing if the destination square is epSquare. if (to == pos.ep_square()) return make_ep_move(from, to); } return make_move(from, to); } /// move_to_string() converts a move to a string in coordinate notation /// (g1f3, a7a8q, etc.). The only special case is castling moves, where we /// print in the e1g1 notation in normal chess mode, and in e1h1 notation in /// Chess960 mode. const std::string move_to_string(Move move) { std::string str; Square from = move_from(move); Square to = move_to(move); if (move == MOVE_NONE) str = "(none)"; else if (move == MOVE_NULL) str = "0000"; else { if (!Chess960) { if (move_is_short_castle(move)) return (from == SQ_E1 ? "e1g1" : "e8g8"); if (move_is_long_castle(move)) return (from == SQ_E1 ? "e1c1" : "e8c8"); } str = square_to_string(from) + square_to_string(to); if (move_is_promotion(move)) str += piece_type_to_char(move_promotion_piece(move), false); } return str; } /// Overload the << operator, to make it easier to print moves. std::ostream &operator << (std::ostream& os, Move m) { return os << move_to_string(m); } /// move_is_ok(), for debugging. bool move_is_ok(Move m) { return square_is_ok(move_from(m)) && square_is_ok(move_to(m)); }