possibleMovements method

Implementation

@override
List<List<int>> possibleMovements(int x, int y, List<List<Piece>> board,
    bool reversedBoard, List<List<int>> lastMovement) {
  List<List<int>> movements = [];

  movements.add([y - 1, x - 1]);
  movements.add([y, x - 1]);
  movements.add([y + 1, x - 1]);
  movements.add([y - 1, x]);
  movements.add([y + 1, x]);
  movements.add([y - 1, x + 1]);
  movements.add([y, x + 1]);
  movements.add([y + 1, x + 1]);

  if ((x + 3) < 8 &&
      isWhite &&
      board[y][x + 3] is Rook &&
      board[y][x + 2] is Empty &&
      board[y][x + 1] is Empty &&
      board[y][x] is King &&
      !(board[y][x + 3] as Rook).alreadyMoved &&
      !(board[y][x] as King).alreadyMoved) {
    movements.add([y, x + 2]);
  }
  if ((x - 4) >= 0 &&
      isWhite &&
      board[y][x - 4] is Rook &&
      board[y][x - 3] is Empty &&
      board[y][x - 2] is Empty &&
      board[y][x - 1] is Empty &&
      board[y][x] is King &&
      !(board[y][x - 4] as Rook).alreadyMoved &&
      !(board[y][x] as King).alreadyMoved) {
    movements.add([y, x - 2]);
  }

  if ((x - 3) >= 0 &&
      !isWhite &&
      board[y][x - 3] is Rook &&
      board[y][x - 2] is Empty &&
      board[y][x - 1] is Empty &&
      board[y][x] is King &&
      !(board[y][x - 3] as Rook).alreadyMoved &&
      !(board[y][x] as King).alreadyMoved) {
    movements.add([y, x - 2]);
  }
  if ((x + 4) < 8 &&
      !isWhite &&
      board[y][x + 4] is Rook &&
      board[y][x + 3] is Empty &&
      board[y][x + 2] is Empty &&
      board[y][x + 1] is Empty &&
      board[y][x] is King &&
      !(board[y][x + 4] as Rook).alreadyMoved &&
      !(board[y][x] as King).alreadyMoved) {
    movements.add([y, x + 2]);
  }
  return movements;
}