/*
GraphicsCanvasのRobot利用の修正。

１．フィールド宣言を以下のように修正。
public class GraphicCanvas extends Canvas {
	Image offScreen;
	Robot r2d2;
	Rectangle rect1,rect2;

２．fillPaintとgetPixelを新しいものに書き換える。

※以下は、新しくしたクラスのソースコード。

*/

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.awt.image.*;

public class GraphicCanvas extends Canvas {
	Image offScreen;
	Robot r2d2;
	Rectangle rect1,rect2;
	
	public GraphicCanvas() {
		super();
		try{
		r2d2 = new Robot();
		} catch(Exception ex){}
		addMouseListener(new MouseAdapter() {
			public void mousePressed(MouseEvent e) {
				fillPaint(e.getX(),e.getY(),Color.red);
				//printClickLoc(e.getX(),e.getY());
			}
		});
	}
		
	// 推奨サイズの設定
	public Dimension getPreferredSize() {
		return new Dimension(200,200);
	}
	
	// ペイント処理
	public void fillPaint(int w, int h,Color c) {
		if (r2d2 == null) {
			System.out.println("Robot is not here.");
			return;
		}
		if (offScreen == null) {
			offScreen = createImage(getSize().width,getSize().height);
		}
		int x1,x2,y;
		int thisW = getSize().width;
		int thisH = getSize().height;
		boolean flg = false;
		rect1 = getParent().getBounds();
		rect2 = getBounds();
		Point p;
		Color c1,c2;
		c1 = getPixel(w,h);
		Graphics g = offScreen.getGraphics();
		Graphics g2 = getGraphics();
		g2.setColor(Color.red);
		Stack st = new Stack();
		st.push(new Point(w,h));
		g.setColor(c);
		do {
			p = (Point)st.pop();
			x1 = p.x;
			x2 = p.x;
			y = p.y;
			if (c.equals(getPixel(x1,y))) continue;
			while(true) {
				x1--;
				if (x1 < 0) break;
				c2 = getPixel(x1,y);
				if (!c1.equals(c2)) break;
			}
			x1++;
			while(true){
				x2++;
				if (x2 >= thisW) break;
				c2 = getPixel(x2,y);
				if (!c1.equals(c2)) break;
			}
			x2--;
			g.drawLine(x1,y,x2,y);
			g2.drawLine(x1,y,x2,y);
			flg = false;
			if (y >= 0) {
				for(int i = x1; i <= x2; i++) {
					if (i >= thisW) break;
					c2 = getPixel(i,y - 1);
					if (c1.equals(c2)) {
						if (!flg)
							st.push(new Point(i,y - 1));
						flg = true;
					} else flg = false;
				}
			}
			flg = false;
			if (y < thisH - 1) {
				for(int i = x1; i <= x2; i++) {
					if (i >= thisW) break;
					c2 = getPixel(i,y + 1);
					if (c1.equals(c2)) {
						if (!flg)
							st.push(new Point(i,y + 1));
						flg = true;
					} else flg = false;
				}
			}
		} while(!st.empty());
		g.dispose();
		g2.dispose();
		repaint();
	}
	
	// クリック地点のColorを得る
	public Color getPixel(int x,int y) {
		Color c1 = r2d2.getPixelColor(x + rect1.x + rect2.x,y + rect1.y + rect2.y);
		return c1;
	}
		
	public void paint(Graphics g) {
		if (offScreen == null)
			offScreen = createImage(getSize().width,getSize().height);
		g.drawImage(offScreen,0,0,this);
	}

}