# Returns a new board.
sub make_move {
my ($board, $from_row, $from_col, $to_row, $to_col, $promo) = @_;
- my $move = _move_to_uci_notation($from_row, $from_col, $to_row, $to_col, $promo);
+ my $move = move_to_uci_notation($from_row, $from_col, $to_row, $to_col, $promo);
my $piece = $board->[$from_row][$from_col];
my $nb = $board->clone();
# en passant?
if ($board->[$to_row][$to_col] eq '-') {
if ($piece eq 'p') {
- $nb->[$to_row + 1][$to_col] = '-';
- } else {
$nb->[$to_row - 1][$to_col] = '-';
- }
- }
- } else {
- if (defined($promo) && $promo ne '') {
- if ($piece eq 'p') {
- $piece = $promo;
} else {
- $piece = uc($promo);
+ $nb->[$to_row + 1][$to_col] = '-';
}
}
}
+ if (defined($promo) && $promo ne '') {
+ if ($piece eq 'p') {
+ $piece = lc($promo);
+ } else {
+ $piece = uc($promo);
+ }
+ }
}
# update the board
return (_row_letter_to_num($2), _col_letter_to_num($1));
}
-sub _move_to_uci_notation {
+sub move_to_uci_notation {
my ($from_row, $from_col, $to_row, $to_col, $promo) = @_;
$promo //= "";
return _pos_to_square($from_row, $from_col) . _pos_to_square($to_row, $to_col) . $promo;
can_reach($board, 'B', $from_row, $from_col, $to_row, $to_col));
}
- # TODO: en passant
if ($piece eq 'p') {
# black pawn
if ($to_col == $from_col && $to_row == $from_row + 1) {
return ($dest_piece eq '-' && $middle_piece eq '-');
}
if (abs($to_col - $from_col) == 1 && $to_row == $from_row + 1) {
- return ($dest_piece ne '-');
+ if ($dest_piece eq '-') {
+ # En passant. TODO: check that the last move was indeed an EP move
+ return ($to_row == 5 && $board->[4][$to_col] eq 'P');
+ } else {
+ return 1;
+ }
}
return 0;
}
return ($dest_piece eq '-' && $middle_piece eq '-');
}
if (abs($to_col - $from_col) == 1 && $to_row == $from_row - 1) {
- return ($dest_piece ne '-');
+ if ($dest_piece eq '-') {
+ # En passant. TODO: check that the last move was indeed an EP move
+ return ($to_row == 2 && $board->[3][$to_col] eq 'p');
+ } else {
+ return 1;
+ }
}
return 0;
}
sub _prettyprint_move_no_check_or_mate {
my ($board, $from_row, $from_col, $to_row, $to_col, $promo) = @_;
my $piece = $board->[$from_row][$from_col];
- my $move = _move_to_uci_notation($from_row, $from_col, $to_row, $to_col, $promo);
+ my $move = move_to_uci_notation($from_row, $from_col, $to_row, $to_col, $promo);
if ($piece eq '-') {
die "Invalid move $move";