// CSE 142, Winter 2008, Marty Stepp
// 
// This program draws random 10x10 rectangles on a DrawingPanel with random 
// positions and colors until it has drawn 20 total red rectangles.
// The program demonstrates random numbers, while loops, and graphics.

import java.awt.*;    // for Graphics, Point
import java.util.*;   // for Random

public class RandomRectangles2 {
	// set to false to turn off println messages
	public static final boolean DEBUG = true;

	public static void main(String[] args) {
		DrawingPanel panel = new DrawingPanel(500, 500);
		Graphics g = panel.getGraphics();
		Random rand = new Random();
		
		// keep drawing rectangles until we get 20 red ones
		Point p = new Point();
		int reds = 0;
		while (reds < 20) {
			if (drawRandomRect(g, rand, p)) {
				// then we drew a red rectangle
				reds++;
				if (DEBUG) {
					System.out.println("Drew red rect #" + reds + " at " + p.x + "," + p.y);
				}
			}
		}
	}
	
	// Returns true if we drew a red rectangle, false otherwise.
	public static boolean drawRandomRect(Graphics g, Random rand, Point p) {
		// choose a random location
		p.x = rand.nextInt(490) + 1;
		p.y = rand.nextInt(490) + 1;
		
		// choose a random color
		int randomColor = rand.nextInt(3);  // 0 -- 2
		if (randomColor == 0) {
			g.setColor(Color.RED);
		} else if (randomColor == 1) {
			g.setColor(Color.GREEN);
		} else {  // 2
			g.setColor(Color.BLUE);
		}
		
		g.fillRect(p.x, p.y, 10, 10);
		
		// return whether or not we drew a red rectangle
		if (randomColor == 0) {
			return true;
		} else {
			return false;
		}
	}
}