NonogramComponent.java

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.util.ArrayList;

import javax.swing.SwingUtilities;
import javax.swing.event.MouseInputListener;

/**
 * Represent the GUI part of a {@link Nonogram}
 */
public class NonogramComponent extends Component implements MouseInputListener {

	/**
	 * 
	 */
	private static final long serialVersionUID = 2252313796820615010L;
	
	private static final int PIXELS_PER_SQUARE = 16;
	
	private ArrayList<NonogramEventListener> listeners;
	private int width;
	private int height;
	private boolean[][] pixels;
	
	/**
	 * Create a graphical representation of a Nonogram
	 * @param width The width in pixels of the Nonogram
	 * @param height The height in pixels of the Nonogram
	 */
	public NonogramComponent(int width, int height) {
		this.width = width;
		this.height = height;
	
		pixels = new boolean[width][height];
		listeners = new ArrayList<NonogramEventListener>();
		
		addMouseMotionListener(this);
		addMouseListener(this);
		setPreferredSize(new Dimension(width*PIXELS_PER_SQUARE+1, height*PIXELS_PER_SQUARE+1));
	}
	
	/**
	 * Add an object that will be notified when events happen
	 * @param listener The objec to notify
	 */
	public void addListener(NonogramEventListener listener) {
		listeners.add(listener);
	}
	
	/**
	 * Set a pixel to white or black
	 * @param x The x coordinate of the pixel to set
	 * @param y The y coordinate of the pixel to set
	 * @param val Set to black if true, otherwise set to white
	 */
	public void setPixel(int x, int y, boolean val) {
		pixels[x][y] = val;
		repaint();
	}
	
	@Override
	public void paint(Graphics g) {
		Graphics2D g2 = (Graphics2D)g;
		
		for (int y = 0; y < height; y++) {
			for (int x = 0; x < width; x++) {
				if (pixels[x][y]) {
					g2.setColor(Color.BLACK);
				} else {
					g2.setColor(Color.WHITE);
				}
				g2.fillRect(x*PIXELS_PER_SQUARE, y*PIXELS_PER_SQUARE, PIXELS_PER_SQUARE, PIXELS_PER_SQUARE);
			}
		}
		
		g2.setColor(Color.BLACK);
		
		for (int x = 0; x <= width; x++) {
			g2.drawLine(x*PIXELS_PER_SQUARE, 0, x*PIXELS_PER_SQUARE, width*PIXELS_PER_SQUARE);
		}
		
		for (int y = 0; y <= width; y++) {
			g2.drawLine(0, y*PIXELS_PER_SQUARE, height*PIXELS_PER_SQUARE, y*PIXELS_PER_SQUARE);
		}
	}
	
	private void mouseUpdate(MouseEvent e) {
		boolean left = SwingUtilities.isLeftMouseButton(e);
		boolean right = SwingUtilities.isRightMouseButton(e);
		int x = e.getX() / PIXELS_PER_SQUARE;
		int y = e.getY() / PIXELS_PER_SQUARE;
		
		if ((left || right) && x < width && y < height && x >= 0 && y >= 0) {
			for (NonogramEventListener listener : listeners) {
				listener.nonogramClicked(x, y, left);
			}
		}
	}

	@Override
	public void mouseDragged(MouseEvent e) {
		mouseUpdate(e);
	}

	@Override
	public void mouseMoved(MouseEvent e) {}

	@Override
	public void mouseClicked(MouseEvent e) {}

	@Override
	public void mouseEntered(MouseEvent e) {}

	@Override
	public void mouseExited(MouseEvent e) {}

	@Override
	public void mousePressed(MouseEvent e) {
		mouseUpdate(e);
	}

	@Override
	public void mouseReleased(MouseEvent e) {}
	
}