Square.java

import java.awt.Color;
import java.awt.Graphics;

/**
 * A single square in a window.
 *
 * <p>
 * Adapterion of Nifty Assignment (http://nifty.stanford.edu/) by Mike Clancy in
 * 2001. Original code by Mike Clancy. Updated Fall 2022 by K. Raven
 * Russell.</p>
 */
public class Square {

    /**
     * The next id when a new square is created.
     */
    private static int nextID = 0;

    /**
     * The X position of the upper left corner of this square.
     */
    private int upperLeftX;

    /**
     * The Y position of the upper left corner of this square.
     */
    private int upperLeftY;

    /**
     * The size of this square.
     */
    private int size;

    /**
     * The color this square.
     */
    private Color color;

    /**
     * The id of this square.
     */
    private int id;

    /**
     * Initialize a square with the given position (specified relative to the
     * WindowManager in which all this is being run), dimensions, and color.
     *
     * @param centerX the x position of the center of this square
     * @param centerY the y position of the center of this square
     * @param size the size of this square
     * @param c the color of this square
     */
    public Square(int centerX, int centerY, int size, Color c) {
        this.upperLeftX = centerX - size / 2;
        this.upperLeftY = centerY - size / 2;
        this.size = size;
        this.color = c;
        this.id = nextID;
        nextID++;
    }

    /**
     * method that checks if a given (x,y) position is within a square.
     *
     * @param x position on grid
     * @param y position on grid
     * @return true if the (x,y) is in square, else false
     */
    public boolean contains(int x, int y) {

        if(x >= this.upperLeftX && x <= (this.upperLeftX+size) && 
                y >= this.upperLeftY && x <= (this.upperLeftY+size)){
            return true;
        }

        return false;
    }

    /**
     * Fetches the id of this square.
     *
     * @return the id of this square
     */
    public int id() {
        return id;
    }

    /**
     * Gets the upper left x position of the square.
     *
     * @return the upper left x position
     */
    public int getUpperLeftX() {
        return upperLeftX;
    }

    /**
     * Gets the upper left y position of the square.
     *
     * @return the upper left y position
     */
    public int getUpperLeftY() {
        return upperLeftY;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean equals(Object o) {
        if (o instanceof Square) {
            Square sq = (Square) o;
            return upperLeftX == sq.upperLeftX
                    && upperLeftY == sq.upperLeftY
                    && size == sq.size;
        }
        return false;
    }

    /**
     * Draw the square, surrounded by a border.
     *
     * @param g the graphics to paint on, assumed not null
     */
    public void paint(Graphics g) {

        
        g.setColor(color);
        g.drawRect(this.upperLeftX, this.upperLeftY, size, size);
        g.fillRect(this.upperLeftX, this.upperLeftY, size, size);
        
    }
}