X-Git-Url: https://git.sesse.net/?p=remoteglot;a=blobdiff_plain;f=Board.pm;h=921de3d9c45f715e7084796aeb1a005bc5270093;hp=2edc07de0c61a37b93ebee9e5aadd73fe29985e2;hb=b9fb6e88fc023303181e384719c8e2d3f19133a2;hpb=2e02751eebe4f5ed406e0f61c6f6eadae0193a41

diff --git a/Board.pm b/Board.pm
index 2edc07d..921de3d 100644
--- a/Board.pm
+++ b/Board.pm
@@ -148,6 +148,8 @@ sub move_to_uci_notation {
 	return _pos_to_square($from_row, $from_col) . _pos_to_square($to_row, $to_col) . $promo;
 }
 
+# Note: This is in general not a validation that the move is actually allowed
+# (e.g. you can castle even though you're in check).
 sub parse_pretty_move {
 	my ($board, $move, $toplay) = @_;
 
@@ -192,16 +194,23 @@ sub parse_pretty_move {
 		for my $col (0..7) {
 			next if (defined($from_col) && $from_col != $col);
 			next if ($board->[$row][$col] ne $piece);
-			next if (!$board->can_reach($piece, $row, $col, $to_row, $to_col));
-
-			# See if doing this move would put us in check
-			# (yes, there are clients that expect us to do this).
-			next if ($board->make_move($row, $col, $to_row, $to_col, $promo)->in_check($side));
 			push @squares, [ $row, $col ];
 		}
 	}
+	if (scalar @squares > 1) {
+		# Filter out pieces which cannot reach this square.
+		@squares = grep { $board->can_reach($piece, $_->[0], $_->[1], $to_row, $to_col) } @squares;
+	}
+	if (scalar @squares > 1) {
+		# See if doing this move would put us in check
+		# (yes, there are clients that expect us to do this).
+		@squares = grep { !$board->make_move($_->[0], $_->[1], $to_row, $to_col, $promo)->in_check($side) } @squares;
+	}
+	if (scalar @squares == 0) {
+		die "Impossible move $move";
+	}
 	if (scalar @squares != 1) {
-		die "Ambigious or impossible move $move";
+		die "Ambigious move $move";
 	}
 	return (@{$squares[0]}, $to_row, $to_col, $promo);
 }
@@ -218,6 +227,45 @@ sub fen {
 	return join('/', @rows);
 }
 
+# Returns a compact bit string describing the same data as fen().
+# This is encoded using a Huffman-like encoding, and should be
+# typically about 1/3 the number of bytes.
+sub bitpacked_fen {
+	my ($board) = @_;
+	my $bits = "";
+
+	for my $row (0..7) {
+		for my $col (0..7) {
+			my $piece = $board->[$row][$col];
+			if ($piece eq '-') {
+				$bits .= "0";
+				next;
+			}
+
+			my $color = (lc($piece) eq $piece) ? 0 : 1;
+			$bits .= "1" . $color;
+
+			if (lc($piece) eq 'p') {
+				$bits .= "0";
+			} elsif (lc($piece) eq 'n') {
+				$bits .= "100";
+			} elsif (lc($piece) eq 'b') {
+				$bits .= "101";
+			} elsif (lc($piece) eq 'r') {
+				$bits .= "1110";
+			} elsif (lc($piece) eq 'q') {
+				$bits .= "11110";
+			} elsif (lc($piece) eq 'k') {
+				$bits .= "11111";
+			} else {
+				die "Unknown piece $piece";
+			}
+		}
+	}
+
+	return pack('b*', $bits);
+}
+
 sub can_reach {
 	my ($board, $piece, $from_row, $from_col, $to_row, $to_col) = @_;