Improve readability and remove redundant code

src/board/board.rs

@@ -104,11 +104,13 @@ impl Board {
             Color::Black => lsb(self.black_pieces[PieceType::King].bitboard),
         };
 
-        self.is_attacked(own_king_square, Color::opponent_color(color))
+        self.is_attacked(own_king_square, color.opponent())
     }
 
-    pub fn pseudo_moves_all(&self, color: Color) -> Vec<Move> {
+    pub fn pseudo_moves_all(&self) -> Vec<Move> {
+        let color = self.state.current_player();
         let mut moves = vec![];
+
         moves.extend(self.pseudo_moves(color, PieceType::Pawn));
         moves.extend(self.pseudo_moves(color, PieceType::Knight));
         moves.extend(self.pseudo_moves(color, PieceType::Bishop));
@@ -245,8 +247,8 @@ pub enum Color {
 }
 
 impl Color {
-    pub const fn opponent_color(color: Self) -> Self {
-        match color {
+    pub const fn opponent(&self) -> Self {
+        match self {
             Self::White => Self::Black,
             Self::Black => Self::White,
         }