Move move prettyprinting into Board.

[remoteglot] / Board.pm

diff --git a/Board.pm b/Board.pm
index feb48937ebe94a5f7036b80f697ced09699b89f5..6af89f39819d16e520d4ff753f0b3db161b901e2 100644 (file)
--- a/Board.pm
+++ b/Board.pm
@@ -126,10 +126,15 @@ sub make_move {
        return $nb;
 }
 
+sub _pos_to_square {
+       my ($row, $col) = @_;
+       return sprintf("%c%d", ord('a') + $col, 8 - $row);
+}
+
 sub _move_to_uci_notation {
        my ($from_row, $from_col, $to_row, $to_col, $promo) = @_;
        $promo //= "";
-       return sprintf("%c%d%c%d%s", ord('a') + $from_col, 8 - $from_row, ord('a') + $to_col, 8 - $to_row, $promo);
+       return _pos_to_square($from_row, $from_col) . _pos_to_square($to_row, $to_col) . $promo;
 }
 
 sub fen {
@@ -343,4 +348,111 @@ sub in_mate {
        return 1;
 }
 
+# Returns the short algebraic form of the move, as well as the new position.
+sub prettyprint_move {
+       my ($board, $from_row, $from_col, $to_row, $to_col, $promo) = @_;
+       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, $promo);
+       if ($nb->in_mate()) {
+               $pretty .= '#';
+       } elsif ($nb->in_check() ne 'none') {
+               $pretty .= '+';
+       }
+       return ($pretty, $nb);
+}
+
+sub _prettyprint_move_no_check_or_mate {
+        my ($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, $promo);
+
+       if ($piece eq '-') {
+               die "Invalid move $move";
+       }
+
+       # white short castling
+       if ($move eq 'e1g1' && $piece eq 'K') {
+               return '0-0';
+       }
+
+       # white long castling
+       if ($move eq 'e1c1' && $piece eq 'K') {
+               return '0-0-0';
+       }
+
+       # black short castling
+       if ($move eq 'e8g8' && $piece eq 'k') {
+               return '0-0';
+       }
+
+       # black long castling
+       if ($move eq 'e8c8' && $piece eq 'k') {
+               return '0-0-0';
+       }
+
+       my $pretty;
+
+       # check if the from-piece is a pawn
+       if (lc($piece) eq 'p') {
+               # attack?
+               if ($from_col != $to_col) {
+                       $pretty = substr($move, 0, 1) . 'x' . _pos_to_square($to_row, $to_col);
+               } else {
+                       $pretty = _pos_to_square($to_row, $to_col);
+
+                       if (defined($promo) && $promo ne '') {
+                               # promotion
+                               $pretty .= "=";
+                               $pretty .= $promo;
+                       }
+               }
+               return $pretty;
+       }
+
+       $pretty = uc($piece);
+
+       # see how many of these pieces could go here, in all
+       my $num_total = 0;
+       for my $col (0..7) {
+               for my $row (0..7) {
+                       next unless ($board->[$row][$col] eq $piece);
+                       ++$num_total if ($board->can_reach($piece, $row, $col, $to_row, $to_col));
+               }
+       }
+
+       # see how many of these pieces from the given row could go here
+       my $num_row = 0;
+       for my $col (0..7) {
+               next unless ($board->[$from_row][$col] eq $piece);
+               ++$num_row if ($board->can_reach($piece, $from_row, $col, $to_row, $to_col));
+       }
+
+       # and same for columns
+       my $num_col = 0;
+       for my $row (0..7) {
+               next unless ($board->[$row][$from_col] eq $piece);
+               ++$num_col if ($board->can_reach($piece, $row, $from_col, $to_row, $to_col));
+       }
+
+       # see if we need to disambiguate
+       if ($num_total > 1) {
+               if ($num_col == 1) {
+                       $pretty .= substr($move, 0, 1);
+               } elsif ($num_row == 1) {
+                       $pretty .= substr($move, 1, 1);
+               } else {
+                       $pretty .= substr($move, 0, 2);
+               }
+       }
+
+       # attack?
+       if ($board->[$to_row][$to_col] ne '-') {
+               $pretty .= 'x';
+       }
+
+       $pretty .= _pos_to_square($to_row, $to_col);
+       return $pretty;
+}
+
 1;