// Allison Obourn
// CS 142 - Spring 2024
// Lecture 3

// a Point represents a coordinate in a 2d system.
// Both x and y are zero in the upper left corner of the graph
// and y increases as it moves down and x increases as it moves
// to the right. Therefore Points will always have positive or zero
// x and y locations

public class Point {
    // the coordinates of this point
    private int x;
    private int y;

    // creates a new Point representing the origin (0, 0).
    public Point() {
        this(0, 0);
    }

    // creates a new Point representing the passed in x and y location
    // precondition: x and y are both greater or equal to zero. If not,
    //              throws an IllegalArgumentException
    public Point(int xStart, int yStart) {
        if (x < 0 || y < 0) {
            throw new IllegalArgumentException();
        }
        x = xStart;
        y = yStart;
    }

    // sets the x coordinate of the point to the passed in value
    // precondition: the passed in x is greater or equal to zero. If not,
    //              throws an IllegalArgumentException
    public void setX(int x) {
        if (x < 0) {
            throw new IllegalArgumentException();
        }
        this.x = x;
    }

    // sets the y coordinate of the point to the passed in value
    // precondition: the passed in y is greater or equal to zero. If not,
    //              throws an IllegalArgumentException
    public void setY(int y) {
        if (y < 0) {
            throw new IllegalArgumentException();
        }
        this.x = x;
    }

    // returns the x coordinate of the point
    public int getX() {
        return x;
    }

    // returns the y coordinate of the point
    public int getY() {
        return y;
    }

    // moves the point the passed in dx amount further right and the
    // passed in dy amount further down.
    // precondition: x + dx and y + dy are both greater or equal to zero.
    //              If not, throws an IllegalArgumentException
    public void translate(int dx, int dy) {
        if (x + dx < 0 || y + dy < 0) {
            throw new IllegalArgumentException();
        }
        x = x + dx;
        y = y + dy;
    }

    // returns the distance from the origin (0, 0) to this particular point.
    public double distanceFromOrigin() {
        return Math.sqrt(x * x + y * y);
    }
}