[board, explorer, moves] Make Board::active_color private

Make the struct attribute private, and export two new methods. A getter, active_color(),
and a setter, set_active_color().

Update all references to the attribute to use the methods.

board/src/board.rs

@@ -14,7 +14,7 @@ pub type FullMoveClock = u32;
 
 #[derive(Clone, Debug, Default, Eq, PartialEq)]
 pub struct Board {
-    pub active_color: Color,
+    active_color: Color,
     pieces: PieceSet,
     pub castling_rights: castle::Rights,
     pub en_passant_target: Option<Square>,
@@ -58,6 +58,19 @@ impl Board {
 }
 
 impl Board {
+    #[must_use]
+    pub fn active_color(&self) -> Color {
+        self.active_color
+    }
+
+    pub fn set_active_color(&mut self, color: Color) {
+        if color == self.active_color {
+            return;
+        }
+
+        self.active_color = color;
+    }
+
     #[must_use]
     pub fn get_piece(&self, square: Square) -> Option<Piece> {
         self.pieces.get(square)

board/src/castle.rs

@@ -78,13 +78,13 @@ impl Board {
     }
 
     pub(crate) fn castling_king(&self, square: Square) -> Option<Piece> {
-        let active_color = self.active_color;
+        let active_color = self.active_color();
         self.get_piece(square)
             .filter(|piece| piece.color == active_color && piece.is_king())
     }
 
     pub(crate) fn castling_rook(&self, square: Square) -> Option<Piece> {
-        let active_color = self.active_color;
+        let active_color = self.active_color();
         self.get_piece(square)
             .filter(|piece| piece.color == active_color && piece.is_rook())
     }

board/src/check.rs

@@ -7,7 +7,7 @@ use chessfriend_core::{Color, Piece};
 impl Board {
     #[must_use]
     pub fn active_color_is_in_check(&self) -> bool {
-        self.unwrapped_color_is_in_check(self.active_color)
+        self.unwrapped_color_is_in_check(self.active_color())
     }
 
     #[must_use]

board/src/fen.rs

@@ -113,7 +113,7 @@ impl ToFenStr for Board {
             }
         }
 
-        write!(fen_string, " {}", self.active_color.to_fen_str()?)
+        write!(fen_string, " {}", self.active_color().to_fen_str()?)
             .map_err(ToFenStrError::FmtError)?;
 
         let castling = [
@@ -224,7 +224,7 @@ impl FromFenStr for Board {
                 .next()
                 .ok_or(FromFenStrError::MissingField(Field::PlayerToMove))?,
         )?;
-        board.active_color = active_color;
+        board.set_active_color(active_color);
 
         let castling_rights = fields
             .next()

board/src/macros.rs

@@ -13,7 +13,7 @@ macro_rules! test_board {
                 chessfriend_core::Square::$square,
                 $crate::PlacePieceStrategy::default());
             )*
-            board.active_color = chessfriend_core::Color::$to_move;
+            board.set_active_color(chessfriend_core::Color::$to_move);
             board.en_passant_target = Some(chessfriend_core::Square::$en_passant);
 
             println!("{}", board.display());

board/src/sight.rs

@@ -32,7 +32,7 @@ impl Board {
     }
 
     pub fn active_sight(&self) -> BitBoard {
-        self.friendly_sight(self.active_color)
+        self.friendly_sight(self.active_color())
     }
 
     /// A [`BitBoard`] of all squares the given color can see.
@@ -45,7 +45,7 @@ impl Board {
     }
 
     pub fn active_color_opposing_sight(&self) -> BitBoard {
-        self.opposing_sight(self.active_color)
+        self.opposing_sight(self.active_color())
     }
 
     /// A [`BitBoard`] of all squares visible by colors that oppose the given color.

explorer/src/main.rs

@@ -283,7 +283,7 @@ fn main() -> Result<(), String> {
     loop {
         if should_print_position {
             println!("{}", &state.position);
-            println!("{} to move.", state.position.board.active_color);
+            println!("{} to move.", state.position.board.active_color());
         }
 
         let readline = editor.readline("\n? ");

moves/src/make_move.rs

@@ -227,7 +227,7 @@ impl<T: BoardProvider> MakeMoveInternal for T {
 
         board.color_can_castle(wing, None)?;
 
-        let active_color = board.active_color;
+        let active_color = board.active_color();
         let parameters = Board::castling_parameters(wing, active_color);
 
         let king = board.remove_piece(parameters.origin.king).unwrap();
@@ -289,9 +289,11 @@ impl<T: BoardProvider> MakeMoveInternal for T {
             HalfMoveClock::Advance => board.half_move_clock += 1,
         }
 
-        board.active_color = board.active_color.next();
+        let previous_active_color = board.active_color();
+        let active_color = previous_active_color.next();
+        board.set_active_color(active_color);
 
-        if board.active_color == Color::White {
+        if active_color == Color::White {
             board.full_move_number += 1;
         }
     }
@@ -343,7 +345,7 @@ impl<T: BoardProvider> MakeMoveInternal for T {
             .get_piece(origin_square)
             .ok_or(MakeMoveError::NoPiece(origin_square))?;
 
-        if active_piece.color != board.active_color {
+        if active_piece.color != board.active_color() {
             return Err(MakeMoveError::NonActiveColor {
                 piece: active_piece,
                 square: origin_square,
@@ -379,17 +381,17 @@ mod tests {
 
         assert_eq!(board.get_piece(Square::C2), None);
         assert_eq!(board.get_piece(Square::C3), Some(piece!(White Pawn)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.half_move_clock, 1);
 
-        board.active_color = Color::White;
+        board.set_active_color(Color::White);
 
         let ply = Move::quiet(Square::C3, Square::C4);
         board.make_move(ply, ValidateMove::Yes)?;
 
         assert_eq!(board.get_piece(Square::C3), None);
         assert_eq!(board.get_piece(Square::C4), Some(piece!(White Pawn)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.half_move_clock, 2);
 
         Ok(())
@@ -405,7 +407,7 @@ mod tests {
         assert!(result.is_err());
         assert_eq!(board.get_piece(Square::C2), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::D2), None);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
         assert_eq!(board.half_move_clock, 0);
     }
 
@@ -423,7 +425,7 @@ mod tests {
 
         assert_eq!(board.get_piece(Square::C2), None);
         assert_eq!(board.get_piece(Square::F5), Some(piece!(White Bishop)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.half_move_clock, 0);
 
         Ok(())
@@ -448,7 +450,7 @@ mod tests {
             Some(Square::E3),
             "en passant square not set"
         );
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.half_move_clock, 1);
 
         let ply = Move::en_passant_capture(Square::F4, Square::E3);
@@ -477,7 +479,7 @@ mod tests {
         let result = board.make_move(ply, ValidateMove::Yes);
 
         assert!(result.is_err());
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
         assert_eq!(board.get_piece(Square::A7), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::A8), None);
         assert_eq!(board.half_move_clock, 0);
@@ -495,7 +497,7 @@ mod tests {
 
         assert_eq!(board.get_piece(Square::F7), None);
         assert_eq!(board.get_piece(Square::F8), Some(piece!(White Queen)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.half_move_clock, 0);
 
         Ok(())
@@ -511,7 +513,7 @@ mod tests {
         let ply = Move::castle(Wing::KingSide);
         board.make_move(ply, ValidateMove::Yes)?;
 
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.get_piece(Square::E1), None);
         assert_eq!(board.get_piece(Square::H1), None);
         assert_eq!(board.get_piece(Square::G1), Some(piece!(White King)));
@@ -533,7 +535,7 @@ mod tests {
         let ply = Move::castle(Wing::QueenSide);
         board.make_move(ply, ValidateMove::Yes)?;
 
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
         assert_eq!(board.get_piece(Square::E1), None);
         assert_eq!(board.get_piece(Square::A1), None);
         assert_eq!(board.get_piece(Square::C1), Some(piece!(White King)));

moves/src/record.rs

@@ -32,7 +32,7 @@ impl MoveRecord {
     #[must_use]
     pub fn new(board: &Board, ply: Move, capture: Option<Piece>) -> Self {
         Self {
-            color: board.active_color,
+            color: board.active_color(),
             ply,
             en_passant_target: board.en_passant_target,
             castling_rights: board.castling_rights,

moves/src/unmake_move.rs

@@ -69,7 +69,7 @@ impl<T: BoardProvider> UnmakeMove for T {
         }
 
         let board = self.board_mut();
-        board.active_color = record.color;
+        board.set_active_color(record.color);
         board.en_passant_target = record.en_passant_target;
         board.castling_rights = record.castling_rights;
         board.half_move_clock = record.half_move_clock;
@@ -238,14 +238,14 @@ mod tests {
         // Verify move was made
         assert_eq!(board.get_piece(Square::C2), None);
         assert_eq!(board.get_piece(Square::C3), Some(piece!(White Pawn)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         board.unmake_move(&record)?;
 
         // Verify original state restored
         assert_eq!(board.get_piece(Square::C2), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::C3), None);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -261,7 +261,7 @@ mod tests {
         assert_eq!(board.get_piece(Square::E2), None);
         assert_eq!(board.get_piece(Square::E4), Some(piece!(White Pawn)));
         assert_eq!(board.en_passant_target, Some(Square::E3));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         board.unmake_move(&record)?;
 
@@ -269,7 +269,7 @@ mod tests {
         assert_eq!(board.get_piece(Square::E2), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::E4), None);
         assert_eq!(board.en_passant_target, None);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -288,14 +288,14 @@ mod tests {
         assert_eq!(board.get_piece(Square::C2), None);
         assert_eq!(board.get_piece(Square::F5), Some(piece!(White Bishop)));
         assert_eq!(record.captured_piece, Some(piece!(Black Rook)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         board.unmake_move(&record)?;
 
         // Verify original state restored
         assert_eq!(board.get_piece(Square::C2), Some(piece!(White Bishop)));
         assert_eq!(board.get_piece(Square::F5), Some(piece!(Black Rook)));
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -335,7 +335,7 @@ mod tests {
             Some(piece!(White Pawn)),
             "captured pawn was not restored"
         );
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         Ok(())
     }
@@ -352,14 +352,14 @@ mod tests {
         // Verify promotion was made
         assert_eq!(board.get_piece(Square::F7), None);
         assert_eq!(board.get_piece(Square::F8), Some(piece!(White Queen)));
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         board.unmake_move(&record)?;
 
         // Verify original pawn is restored
         assert_eq!(board.get_piece(Square::F7), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::F8), None);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -384,7 +384,7 @@ mod tests {
         // Verify original state restored
         assert_eq!(board.get_piece(Square::F7), Some(piece!(White Pawn)));
         assert_eq!(board.get_piece(Square::G8), Some(piece!(Black Rook)));
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -418,7 +418,7 @@ mod tests {
         assert_eq!(board.get_piece(Square::G1), None);
         assert_eq!(board.get_piece(Square::F1), None);
         assert_eq!(board.castling_rights, original_castling_rights);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -452,7 +452,7 @@ mod tests {
         assert_eq!(board.get_piece(Square::C1), None);
         assert_eq!(board.get_piece(Square::D1), None);
         assert_eq!(board.castling_rights, original_castling_rights);
-        assert_eq!(board.active_color, Color::White);
+        assert_eq!(board.active_color(), Color::White);
 
         Ok(())
     }
@@ -463,7 +463,7 @@ mod tests {
             Black King on E8,
             Black Rook on H8,
         ];
-        board.active_color = Color::Black;
+        board.set_active_color(Color::Black);
 
         let original_castling_rights = board.castling_rights;
 
@@ -484,7 +484,7 @@ mod tests {
         assert_eq!(board.get_piece(Square::G8), None);
         assert_eq!(board.get_piece(Square::F8), None);
         assert_eq!(board.castling_rights, original_castling_rights);
-        assert_eq!(board.active_color, Color::Black);
+        assert_eq!(board.active_color(), Color::Black);
 
         Ok(())
     }