$pos->{'board'} = Board->new(@x[1..8]);
$pos->{'toplay'} = $x[9];
$pos->{'ep_file_num'} = $x[10];
- $pos->{'white_castle_k'} = $x[11];
- $pos->{'white_castle_q'} = $x[12];
- $pos->{'black_castle_k'} = $x[13];
- $pos->{'black_castle_q'} = $x[14];
+ $pos->{'white_castle_k'} = $x[11] ? 'h' : undef;
+ $pos->{'white_castle_q'} = $x[12] ? 'a' : undef;
+ $pos->{'black_castle_k'} = $x[13] ? 'h' : undef;
+ $pos->{'black_castle_q'} = $x[14] ? 'a' : undef;
$pos->{'time_since_100move_rule_reset'} = $x[15];
$pos->{'player_w'} = $x[17];
$pos->{'player_b'} = $x[18];
my $pos = {};
$board =~ s/(\d)/"-"x$1/ge;
$pos->{'board'} = Board->new(split /\//, $board);
+ $board = $pos->{'board'};
$pos->{'toplay'} = uc($toplay);
if ($ep_square =~ /^([a-h])/) {
$pos->{'ep_file_num'} = -1;
}
- $pos->{'white_castle_k'} = ($castling =~ /K/) ? 1 : 0;
- $pos->{'white_castle_q'} = ($castling =~ /Q/) ? 1 : 0;
- $pos->{'black_castle_k'} = ($castling =~ /k/) ? 1 : 0;
- $pos->{'black_castle_q'} = ($castling =~ /q/) ? 1 : 0;
+ # X-FEN castling rights parsing.
+ if ($castling =~ /K/) {
+ $pos->{'white_castle_k'} = _col_num_to_letter(_find_piece_col_from_right($board->[7], 'R'));
+ }
+ if ($castling =~ /Q/) {
+ $pos->{'white_castle_q'} = _col_num_to_letter(_find_piece_col($board->[7], 'R'));
+ }
+ while ($castling =~ s/([A-H])//) {
+ my $rook_col = lc($1);
+ my $king_col = _col_num_to_letter(_find_piece_col($board->[7], 'K'));
+ if ($rook_col lt $king_col) {
+ $pos->{'white_castle_q'} = $rook_col;
+ } else {
+ $pos->{'white_castle_k'} = $rook_col;
+ }
+ }
+ if ($castling =~ /k/) {
+ $pos->{'black_castle_k'} = _col_num_to_letter(_find_piece_col_from_right($board->[0], 'r'));
+ }
+ if ($castling =~ /q/) {
+ $pos->{'black_castle_q'} = _col_num_to_letter(_find_piece_col($board->[0], 'r'));
+ }
+ while ($castling =~ s/([a-h])//) {
+ my $rook_col = $1;
+ my $king_col = _col_num_to_letter(_find_piece_col($board->[0], 'k'));
+ if ($rook_col lt $king_col) {
+ $pos->{'black_castle_q'} = $rook_col;
+ } else {
+ $pos->{'black_castle_k'} = $rook_col;
+ }
+ }
$pos->{'time_since_100move_rule_reset'} = $halfmove_clock // 0;
$pos->{'player_w'} = 'white';
$pos->{'player_b'} = 'black';
$fen .= " ";
$fen .= lc($pos->{'toplay'});
- # castling
+ # Castling (X-FEN compatible).
my $castling = "";
- $castling .= "K" if ($pos->{'white_castle_k'} == 1);
- $castling .= "Q" if ($pos->{'white_castle_q'} == 1);
- $castling .= "k" if ($pos->{'black_castle_k'} == 1);
- $castling .= "q" if ($pos->{'black_castle_q'} == 1);
+ if (defined($pos->{'white_castle_k'})) {
+ my $outer_rook_col = _col_num_to_letter(_find_piece_col_from_right($pos->{'board'}[7], 'R'));
+ if ($outer_rook_col eq $pos->{'white_castle_k'}) {
+ $castling .= "K";
+ } else {
+ $castling .= uc($pos->{'white_castle_k'});
+ }
+ }
+ if (defined($pos->{'white_castle_q'})) {
+ my $outer_rook_col = _col_num_to_letter(_find_piece_col($pos->{'board'}[7], 'R'));
+ if ($outer_rook_col eq $pos->{'white_castle_q'}) {
+ $castling .= "Q";
+ } else {
+ $castling .= uc($pos->{'white_castle_q'});
+ }
+ }
+ if (defined($pos->{'black_castle_k'})) {
+ my $outer_rook_col = _col_num_to_letter(_find_piece_col_from_right($pos->{'board'}[0], 'r'));
+ if ($outer_rook_col eq $pos->{'black_castle_k'}) {
+ $castling .= "k";
+ } else {
+ $castling .= $pos->{'black_castle_k'};
+ }
+ }
+ if (defined($pos->{'black_castle_q'})) {
+ my $outer_rook_col = _col_num_to_letter(_find_piece_col($pos->{'board'}[0], 'r'));
+ if ($outer_rook_col eq $pos->{'black_castle_q'}) {
+ $castling .= "q";
+ } else {
+ $castling .= $pos->{'black_castle_q'};
+ }
+ }
$castling = "-" if ($castling eq "");
# $castling = "-"; # chess960
$fen .= " ";
sub parse_pretty_move {
my ($pos, $move) = @_;
- return $pos->{'board'}->parse_pretty_move($move, $pos->{'toplay'});
+ return $pos->{'board'}->parse_pretty_move($move, $pos->{'toplay'}, $pos->{'chess960'}, $pos->{'white_castle_k'}, $pos->{'white_castle_q'}, $pos->{'black_castle_k'}, $pos->{'black_castle_q'});
}
sub num_pieces {
$np->{'black_castle_k'} = $pos->{'black_castle_k'};
$np->{'black_castle_q'} = $pos->{'black_castle_q'};
if ($piece eq 'K') {
- $np->{'white_castle_k'} = 0;
- $np->{'white_castle_q'} = 0;
+ $np->{'white_castle_k'} = undef;
+ $np->{'white_castle_q'} = undef;
} elsif ($piece eq 'k') {
- $np->{'black_castle_k'} = 0;
- $np->{'black_castle_q'} = 0;
- } elsif ($from_square eq 'a1' || $to_square eq 'a1') {
- $np->{'white_castle_q'} = 0;
- } elsif ($from_square eq 'h1' || $to_square eq 'h1') {
- $np->{'white_castle_k'} = 0;
- } elsif ($from_square eq 'a8' || $to_square eq 'a8') {
- $np->{'black_castle_q'} = 0;
- } elsif ($from_square eq 'h8' || $to_square eq 'h8') {
- $np->{'black_castle_k'} = 0;
+ $np->{'black_castle_k'} = undef;
+ $np->{'black_castle_q'} = undef;
+ } elsif (defined($np->{'white_castle_q'}) &&
+ ($from_square eq ($np->{'white_castle_q'} . '1') ||
+ $to_square eq ($np->{'white_castle_q'} . '1'))) {
+ $np->{'white_castle_q'} = undef;
+ } elsif (defined($np->{'white_castle_k'}) &&
+ ($from_square eq ($np->{'white_castle_k'} . '1') ||
+ $to_square eq ($np->{'white_castle_k'} . '1'))) {
+ $np->{'white_castle_k'} = undef;
+ } elsif (defined($np->{'black_castle_q'}) &&
+ ($from_square eq ($np->{'black_castle_q'} . '8') ||
+ $to_square eq ($np->{'black_castle_q'} . '8'))) {
+ $np->{'black_castle_q'} = undef;
+ } elsif (defined($np->{'black_castle_k'}) &&
+ ($from_square eq ($np->{'black_castle_k'} . '8') ||
+ $to_square eq ($np->{'black_castle_k'} . '8'))) {
+ $np->{'black_castle_k'} = undef;
}
- # 50-move rule.
- if (lc($piece) eq 'p' || $dest_piece ne '-') {
+ # 50-move rule. Note that castle does not reset the counter, per FIDE rules.
+ my $castling = (lc($piece) eq 'k' && abs($from_col - $to_col) > 1) || # King moves two squares.
+ ($piece eq 'K' && $dest_piece eq 'R') || # Chess960-style king-takes-rook.
+ ($piece eq 'k' && $dest_piece eq 'r');
+ if (!$castling && (lc($piece) eq 'p' || $dest_piece ne '-')) {
$np->{'time_since_100move_rule_reset'} = 0;
} else {
$np->{'time_since_100move_rule_reset'} = $pos->{'time_since_100move_rule_reset'} + 1;
return $pvpos;
}
+sub _col_num_to_letter {
+ my $col = shift;
+ return sprintf("%c", ord('a') + $col);
+}
+
sub _col_letter_to_num {
return ord(shift) - ord('a');
}
return 7 - (ord(shift) - ord('1'));
}
+sub _find_piece_col {
+ my ($row, $piece) = @_;
+ for my $col (0..7) {
+ return $col if ($row->[$col] eq $piece);
+ }
+ die "Could not find piece $piece";
+}
+
+sub _find_piece_col_from_right {
+ my ($row, $piece) = @_;
+ for my $col (reverse 0..7) {
+ return $col if ($row->[$col] eq $piece);
+ }
+ die "Could not find piece $piece";
+}
+
sub _parse_uci_move {
my $move = shift;
my $from_col = _col_letter_to_num(substr($move, 0, 1));