X-Git-Url: https://git.sesse.net/?p=remoteglot;a=blobdiff_plain;f=Board.pm;h=2edc07de0c61a37b93ebee9e5aadd73fe29985e2;hp=f011b17510221f65774c1ae249a71243f1d451c5;hb=e8d50f04060a581d1380d03e50de49ab592f3188;hpb=3b624f881c25e5455e2972eb2d22efe37a5c9f38 diff --git a/Board.pm b/Board.pm index f011b17..2edc07d 100644 --- a/Board.pm +++ b/Board.pm @@ -170,7 +170,7 @@ sub parse_pretty_move { # Parse promo my $promo; - if ($move =~ s/=([QRNB])$//) { + if ($move =~ s/=?([QRNB])$//) { $promo = $1; } @@ -182,8 +182,10 @@ sub parse_pretty_move { # Find all possible from-squares that could have been meant. my @squares = (); + my $side = 'K'; if ($toplay eq 'B') { $piece = lc($piece); + $side = 'k'; } for my $row (0..7) { next if (defined($from_row) && $from_row != $row); @@ -194,11 +196,7 @@ sub parse_pretty_move { # See if doing this move would put us in check # (yes, there are clients that expect us to do this). - my $check = $board->make_move($row, $col, $to_row, $to_col, $promo)->in_check(); - next if ($check eq 'both' || - ($toplay eq 'W' && $check eq 'white') || - ($toplay eq 'B' && $check eq 'black')); - + next if ($board->make_move($row, $col, $to_row, $to_col, $promo)->in_check($side)); push @squares, [ $row, $col ]; } } @@ -228,10 +226,46 @@ sub can_reach { if ($dest_piece ne '-') { return 0 if (($piece eq lc($piece)) == ($dest_piece eq lc($dest_piece))); } - - if (lc($piece) eq 'k') { - return (abs($from_row - $to_row) <= 1 && abs($from_col - $to_col) <= 1); + + if ($piece eq 'p') { + # black pawn + if ($to_col == $from_col && $to_row == $from_row + 1) { + return ($dest_piece eq '-'); + } + if ($to_col == $from_col && $from_row == 1 && $to_row == 3) { + my $middle_piece = $board->[2][$to_col]; + return ($dest_piece eq '-' && $middle_piece eq '-'); + } + if (abs($to_col - $from_col) == 1 && $to_row == $from_row + 1) { + if ($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; + } + if ($piece eq 'P') { + # white pawn + if ($to_col == $from_col && $to_row == $from_row - 1) { + return ($dest_piece eq '-'); + } + if ($to_col == $from_col && $from_row == 6 && $to_row == 4) { + my $middle_piece = $board->[5][$to_col]; + return ($dest_piece eq '-' && $middle_piece eq '-'); + } + if (abs($to_col - $from_col) == 1 && $to_row == $from_row - 1) { + if ($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; } + if (lc($piece) eq 'r') { return 0 unless ($from_row == $to_row || $from_col == $to_col); @@ -294,107 +328,56 @@ sub can_reach { return (can_reach($board, 'R', $from_row, $from_col, $to_row, $to_col) || can_reach($board, 'B', $from_row, $from_col, $to_row, $to_col)); } - - if ($piece eq 'p') { - # black pawn - if ($to_col == $from_col && $to_row == $from_row + 1) { - return ($dest_piece eq '-'); - } - if ($to_col == $from_col && $from_row == 1 && $to_row == 3) { - my $middle_piece = $board->[2][$to_col]; - return ($dest_piece eq '-' && $middle_piece eq '-'); - } - if (abs($to_col - $from_col) == 1 && $to_row == $from_row + 1) { - if ($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; - } - if ($piece eq 'P') { - # white pawn - if ($to_col == $from_col && $to_row == $from_row - 1) { - return ($dest_piece eq '-'); - } - if ($to_col == $from_col && $from_row == 6 && $to_row == 4) { - my $middle_piece = $board->[5][$to_col]; - return ($dest_piece eq '-' && $middle_piece eq '-'); - } - if (abs($to_col - $from_col) == 1 && $to_row == $from_row - 1) { - if ($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; + if (lc($piece) eq 'k') { + return (abs($from_row - $to_row) <= 1 && abs($from_col - $to_col) <= 1); } - + # unknown piece return 0; } -# Returns 'none', 'white', 'black' or 'both', depending on which sides are in check. -# The latter naturally indicates an invalid position. -sub in_check { - my $board = shift; - my ($black_check, $white_check) = (0, 0); +my %pieces_against_side = ( + k => { K => 1, Q => 1, R => 1, N => 1, B => 1, P => 1 }, + K => { k => 1, q => 1, r => 1, n => 1, b => 1, p => 1 }, +); - my ($wkr, $wkc, $bkr, $bkc) = _find_kings($board); +# Returns whether the given side (given as k or K for black and white) is in check. +sub in_check { + my ($board, $side) = @_; + my ($kr, $kc) = _find_piece($board, $side); - # check all pieces for the possibility of threatening the two kings + # check all pieces for the possibility of threatening this king for my $row (0..7) { + next unless grep { exists($pieces_against_side{$side}{$_}) } @{$board->[$row]}; for my $col (0..7) { my $piece = $board->[$row][$col]; next if ($piece eq '-'); - - if (uc($piece) eq $piece) { - # white piece - $black_check = 1 if ($board->can_reach($piece, $row, $col, $bkr, $bkc)); - } else { - # black piece - $white_check = 1 if ($board->can_reach($piece, $row, $col, $wkr, $wkc)); - } + return 1 if ($board->can_reach($piece, $row, $col, $kr, $kc)); } } - if ($black_check && $white_check) { - return 'both'; - } elsif ($black_check) { - return 'black'; - } elsif ($white_check) { - return 'white'; - } else { - return 'none'; - } + return 0; } -sub _find_kings { - my $board = shift; - my ($wkr, $wkc, $bkr, $bkc); +sub _find_piece { + my ($board, $piece) = @_; for my $row (0..7) { + next unless grep { $_ eq $piece } @{$board->[$row]}; for my $col (0..7) { - my $piece = $board->[$row][$col]; - if ($piece eq 'K') { - ($wkr, $wkc) = ($row, $col); - } elsif ($piece eq 'k') { - ($bkr, $bkc) = ($row, $col); + if ($board->[$row][$col] eq $piece) { + return ($row, $col); } } } - return ($wkr, $wkc, $bkr, $bkc); + return (undef, undef); } -# Returns if any side is in mate. +# Returns if the given side (given as k or K) is in mate. sub in_mate { - my ($board, $check) = @_; - return 0 if ($check eq 'none'); + my ($board, $side, $in_check) = @_; + return 0 if (!$in_check); # try all possible moves for the side in check for my $row (0..7) { @@ -402,7 +385,7 @@ sub in_mate { my $piece = $board->[$row][$col]; next if ($piece eq '-'); - if ($check eq 'white') { + if ($side eq 'K') { next if ($piece eq lc($piece)); } else { next if ($piece eq uc($piece)); @@ -413,11 +396,8 @@ sub in_mate { next if ($row == $dest_row && $col == $dest_col); next unless ($board->can_reach($piece, $row, $col, $dest_row, $dest_col)); - my $nb = $board->clone(); - $nb->[$row][$col] = '-'; - $nb->[$dest_row][$dest_col] = $piece; - my $new_check = $nb->in_check(); - return 0 if ($new_check ne $check && $new_check ne 'both'); + my $nb = $board->make_move($row, $col, $dest_row, $dest_col); + return 0 if (!$nb->in_check($side)); } } } @@ -433,15 +413,31 @@ sub prettyprint_move { my $pretty = $board->_prettyprint_move_no_check_or_mate($from_row, $from_col, $to_row, $to_col, $promo); my $nb = $board->make_move($from_row, $from_col, $to_row, $to_col, $promo); - my $check = $nb->in_check(); - if ($nb->in_mate($check)) { + + my $piece = $board->[$from_row][$from_col]; + my $other_side = (uc($piece) eq $piece) ? 'k' : 'K'; + my $in_check = $nb->in_check($other_side); + if ($nb->in_mate($other_side, $in_check)) { $pretty .= '#'; - } elsif ($check ne 'none') { + } elsif ($in_check) { $pretty .= '+'; } return ($pretty, $nb); } +sub num_pieces { + my ($board) = @_; + + my $num = 0; + for my $row (0..7) { + for my $col (0..7) { + my $piece = $board->[$row][$col]; + ++$num if ($piece ne '-'); + } + } + return $num; +} + sub _prettyprint_move_no_check_or_mate { my ($board, $from_row, $from_col, $to_row, $to_col, $promo) = @_; my $piece = $board->[$from_row][$from_col]; @@ -484,7 +480,7 @@ sub _prettyprint_move_no_check_or_mate { if (defined($promo) && $promo ne '') { # promotion $pretty .= "="; - $pretty .= $promo; + $pretty .= uc($promo); } } return $pretty;