private List<Movement> listPositionsToMove(Player player) {
		if (player == null)
			throw new IllegalArgumentException("Player can't be null!");

		List<Movement> possibleMovements = new ArrayList<Movement>();

		for (Movement move : Movement.values()) {
			if (grid.canMove(player, move))
				possibleMovements.add(move);
		}

		return possibleMovements;
	}