+/// move_to_uci() 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_uci(Move m, bool chess960) {
+
+ std::string str;
+ Square from = move_from(m);
+ Square to = move_to(m);
+
+ if (m == MOVE_NONE)
+ return "(none)";
+
+ if (m == MOVE_NULL)
+ return "0000";
+
+ if (move_is_short_castle(m) && !chess960)
+ return from == SQ_E1 ? "e1g1" : "e8g8";
+
+ if (move_is_long_castle(m) && !chess960)
+ return from == SQ_E1 ? "e1c1" : "e8c8";
+
+ str = square_to_string(from) + square_to_string(to);
+
+ if (move_is_promotion(m))
+ str += char(tolower(piece_type_to_char(move_promotion_piece(m))));
+
+ return str;
+}
+
+/// move_from_uci() takes a position and a string as input, and attempts to
+/// convert the string to a move, using simple coordinate notation (g1f3,
+/// a7a8q, etc.). This function is not robust, and expects that the input
+/// move is legal and correctly formatted.
+
+Move move_from_uci(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 = make_square(file_from_char(str[0]), rank_from_char(str[1]));
+ to = make_square(file_from_char(str[2]), rank_from_char(str[3]));
+
+ // 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 (str.length() > 4 && piece == piece_of_color_and_type(us, PAWN))
+ {
+ 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);
+ }
+ }
+
+ // En passant move? We assume that a pawn move is an en passant move
+ // if the destination square is epSquare.
+ if (to == pos.ep_square() && piece == piece_of_color_and_type(us, PAWN))
+ return make_ep_move(from, to);
+
+ // 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 (piece == piece_of_color_and_type(us, KING))
+ {
+ if (pos.piece_on(to) == piece_of_color_and_type(us, ROOK))
+ return make_castle_move(from, to);
+
+ 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;
+
+ do s += delta;
+ while ( pos.piece_on(s) != piece_of_color_and_type(us, ROOK)
+ && relative_rank(us, s) == RANK_1);
+
+ return relative_rank(us, s) == RANK_1 ? make_castle_move(from, s) : MOVE_NONE;
+ }
+ }
+
+ return make_move(from, to);
+}
+
+