void move_do(board_t * board, int move, undo_t * undo) {
int me, opp;
int from, to;
int piece, pos, capture;
int old_flags, new_flags;
int delta;
int sq;
int pawn, rook;
ASSERT(board!=NULL);
ASSERT(move_is_ok(move));
ASSERT(undo!=NULL);
ASSERT(board_is_legal(board));
// initialise undo
undo->capture = false;
undo->turn = board->turn;
undo->flags = board->flags;
undo->ep_square = board->ep_square;
undo->ply_nb = board->ply_nb;
undo->cap_sq = board->cap_sq;
undo->opening = board->opening;
undo->endgame = board->endgame;
undo->key = board->key;
undo->pawn_key = board->pawn_key;
undo->material_key = board->material_key;
// init
me = board->turn;
opp = COLOUR_OPP(me);
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[from];
ASSERT(COLOUR_IS(piece,me));
// update key stack
ASSERT(board->sp<StackSize);
board->stack[board->sp++] = board->key;
// update turn
board->turn = opp;
board->key ^= RANDOM_64(RandomTurn);
// update castling rights
old_flags = board->flags;
new_flags = old_flags & CastleMask[from] & CastleMask[to];
board->flags = new_flags;
board->key ^= Castle64[new_flags^old_flags]; // HACK
// update en-passant square
if ((sq=board->ep_square) != SquareNone) {
board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(sq)-FileA);
board->ep_square = SquareNone;
}
if (PIECE_IS_PAWN(piece)) {
delta = to - from;
if (delta == +32 || delta == -32) {
pawn = PAWN_MAKE(opp);
if (board->square[to-1] == pawn || board->square[to+1] == pawn) {
board->ep_square = (from + to) / 2;
board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(to)-FileA);
}
}
}
// update move number (captures are handled later)
board->ply_nb++;
if (PIECE_IS_PAWN(piece)) board->ply_nb = 0; // conversion
// update last square
board->cap_sq = SquareNone;
// remove the captured piece
sq = to;
if (MOVE_IS_EN_PASSANT(move)) sq = SQUARE_EP_DUAL(sq);
if ((capture=board->square[sq]) != Empty) {
ASSERT(COLOUR_IS(capture,opp));
ASSERT(!PIECE_IS_KING(capture));
undo->capture = true;
undo->capture_square = sq;
undo->capture_piece = capture;
undo->capture_pos = board->pos[sq];
square_clear(board,sq,capture,true);
board->ply_nb = 0; // conversion
board->cap_sq = to;
}
// move the piece
if (MOVE_IS_PROMOTE(move)) {
// promote
undo->pawn_pos = board->pos[from];
square_clear(board,from,piece,true);
piece = move_promote(move);
// insert the promote piece in MV order
for (pos = board->piece_size[me]; pos > 0 && piece > board->square[board->piece[me][pos-1]]; pos--) // HACK
;
square_set(board,to,piece,pos,true);
board->cap_sq = to;
} else {
// normal move
square_move(board,from,to,piece,true);
}
// move the rook in case of castling
if (MOVE_IS_CASTLE(move)) {
rook = Rook64 | COLOUR_FLAG(me); // HACK
if (to == G1) {
square_move(board,H1,F1,rook,true);
} else if (to == C1) {
square_move(board,A1,D1,rook,true);
} else if (to == G8) {
square_move(board,H8,F8,rook,true);
} else if (to == C8) {
square_move(board,A8,D8,rook,true);
} else {
ASSERT(false);
}
}
// debug
ASSERT(board_is_ok(board));
}
void move_do(board_t * board, int move) {
int me, opp;
int from, to;
int piece, pos, capture;
int old_flags, new_flags;
int sq, ep_square;
int pawn;
ASSERT(board_is_ok(board));
ASSERT(move_is_ok(move));
ASSERT(move_is_pseudo(move,board));
// init
me = board->turn;
opp = colour_opp(me);
from = move_from(move);
to = move_to(move);
piece = board->square[from];
ASSERT(colour_equal(piece,me));
pos = board->pos[from];
ASSERT(pos>=0);
// update turn
board->turn = opp;
board->key ^= random_64(RandomTurn);
// update castling rights
old_flags = board_flags(board);
if (piece_is_king(piece)) {
board->castle[me][SideH] = SquareNone;
board->castle[me][SideA] = SquareNone;
}
if (board->castle[me][SideH] == from) board->castle[me][SideH] = SquareNone;
if (board->castle[me][SideA] == from) board->castle[me][SideA] = SquareNone;
if (board->castle[opp][SideH] == to) board->castle[opp][SideH] = SquareNone;
if (board->castle[opp][SideA] == to) board->castle[opp][SideA] = SquareNone;
new_flags = board_flags(board);
board->key ^= hash_castle_key(new_flags^old_flags); // HACK
// update en-passant square
ep_square = sq = board->ep_square;
if (sq != SquareNone) {
board->key ^= random_64(RandomEnPassant+square_file(sq));
board->ep_square = SquareNone;
}
if (piece_is_pawn(piece) && abs(to-from) == 32) {
pawn = piece_make_pawn(opp);
if (board->square[to-1] == pawn || board->square[to+1] == pawn) {
board->ep_square = sq = (from + to) / 2;
board->key ^= random_64(RandomEnPassant+square_file(sq));
}
}
// update ply number (captures are handled later)
board->ply_nb++;
if (piece_is_pawn(piece)) board->ply_nb = 0; // conversion
// update move number
if (me == Black) board->move_nb++;
// castle
if (colour_equal(board->square[to],me)) {
int rank;
int king_from, king_to;
int rook_from, rook_to;
int rook;
rank = colour_is_white(me) ? Rank1 : Rank8;
king_from = from;
rook_from = to;
if (to > from) { // h side
king_to = square_make(FileG,rank);
rook_to = square_make(FileF,rank);
} else { // a side
king_to = square_make(FileC,rank);
rook_to = square_make(FileD,rank);
}
// remove the rook
pos = board->pos[rook_from];
ASSERT(pos>=0);
rook = Rook64 | me; // HACK
square_clear(board,rook_from,rook);
// move the king
square_move(board,king_from,king_to,piece);
// put the rook back
square_set(board,rook_to,rook,pos);
ASSERT(board->key==hash_key(board));
return;
}
// remove the captured piece
if (piece_is_pawn(piece) && to == ep_square) {
// en-passant capture
sq = square_ep_dual(to);
capture = board->square[sq];
ASSERT(capture==piece_make_pawn(opp));
square_clear(board,sq,capture);
board->ply_nb = 0; // conversion
} else {
capture = board->square[to];
if (capture != Empty) {
// normal capture
ASSERT(colour_equal(capture,opp));
ASSERT(!piece_is_king(capture));
square_clear(board,to,capture);
board->ply_nb = 0; // conversion
}
}
// move the piece
if (move_is_promote(move)) {
// promote
square_clear(board,from,piece);
piece = move_promote_hack(move) | me; // HACK
square_set(board,to,piece,pos);
} else {
// normal move
square_move(board,from,to,piece);
}
ASSERT(board->key==hash_key(board));
}
void move_undo(board_t * board, int move, const undo_t * undo) {
int me;
int from, to;
int piece, pos;
int rook;
ASSERT(board!=NULL);
ASSERT(move_is_ok(move));
ASSERT(undo!=NULL);
// init
me = undo->turn;
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[to];
ASSERT(COLOUR_IS(piece,me));
// castle
if (MOVE_IS_CASTLE(move)) {
rook = Rook64 | COLOUR_FLAG(me); // HACK
if (to == G1) {
square_move(board,F1,H1,rook,false);
} else if (to == C1) {
square_move(board,D1,A1,rook,false);
} else if (to == G8) {
square_move(board,F8,H8,rook,false);
} else if (to == C8) {
square_move(board,D8,A8,rook,false);
} else {
ASSERT(false);
}
}
// move the piece backward
if (MOVE_IS_PROMOTE(move)) {
// promote
ASSERT(piece==move_promote(move));
square_clear(board,to,piece,false);
piece = PAWN_MAKE(me);
pos = undo->pawn_pos;
square_set(board,from,piece,pos,false);
} else {
// normal move
square_move(board,to,from,piece,false);
}
// put the captured piece back
if (undo->capture) {
square_set(board,undo->capture_square,undo->capture_piece,undo->capture_pos,false);
}
// update board info
board->turn = undo->turn;
board->flags = undo->flags;
board->ep_square = undo->ep_square;
board->ply_nb = undo->ply_nb;
board->cap_sq = undo->cap_sq;
board->opening = undo->opening;
board->endgame = undo->endgame;
board->key = undo->key;
board->pawn_key = undo->pawn_key;
board->material_key = undo->material_key;
// update key stack
ASSERT(board->sp>0);
board->sp--;
// debug
ASSERT(board_is_ok(board));
ASSERT(board_is_legal(board));
}
