RobotSimulator/src/main/java/au/com/seek/domain/Direction.java

package au.com.seek.domain;


public enum Direction {
    NORTH {
        @Override
        public Direction turnRight() {
            return EAST;
        }

        @Override
        public Direction turnLeft() {
            return WEST;
        }

        @Override
        public int stepValueOnXAxis() {
            return 0;
        }

        @Override
        public int stepValueOnYAxis() {
            return STEP_VALUE;
        }
    },
    EAST {
        @Override
        public Direction turnRight() {
            return SOUTH;
        }

        @Override
        public Direction turnLeft() {
            return NORTH;
        }

        @Override
        public int stepValueOnXAxis() {
            return STEP_VALUE;
        }

        @Override
        public int stepValueOnYAxis() {
            return 0;
        }
    },
    SOUTH {
        @Override
        public Direction turnRight() {
            return WEST;
        }

        @Override
        public Direction turnLeft() {
            return EAST;
        }

        @Override
        public int stepValueOnXAxis() {
            return 0;
        }

        @Override
        public int stepValueOnYAxis() {
            return NEGATIVE_STEP_VALUE;
        }
    },
    WEST {
        @Override
        public Direction turnRight() {
            return NORTH;
        }

        @Override
        public Direction turnLeft() {
            return SOUTH;
        }

        @Override
        public int stepValueOnXAxis() {
            return NEGATIVE_STEP_VALUE;
        }

        @Override
        public int stepValueOnYAxis() {
            return 0;
        }
    };

    private static final int NEGATIVE_STEP_VALUE = -1;
    private static final int STEP_VALUE = 1;

    public abstract Direction turnRight();

    public abstract Direction turnLeft();

    public abstract int stepValueOnXAxis();

    public abstract int stepValueOnYAxis();
}