//0.4  加入repaint畫面重畫機制  使用雙緩沖使得畫面更流暢
//0.5  加入兩個常量，用于分辨率更改容易些；
//0.6  加入鍵盤監聽類，使坦克隨鍵盤動起來，四個方向
//0.7  加入坦克類，用于生成多個坦克
//0.8  加入了八個方向,利用布爾來控制坦克的行進方向
//0.9  對按鍵抬起的響應處理
//1.0  增加子彈類
//1.1  按CTRL鍵的按鍵處理  “打出一發炮彈”
//1.2  解決坦克靜止時 炮彈停留在原地的問題 加入炮筒
//1.3  加入一個容器用于存放打出的炮彈
//1.4  解決對象出界問題，將出界對象銷毀
//1.5  加入一個布爾類型用于判斷坦克敵我
//1.6  增加碰撞檢測,子彈"打中"坦克后,子彈與坦克都消失

import java.awt.*;
import java.awt.event.*;
import java.util.LinkedList;
import java.util.List;

public class TankClient extends Frame{
	
	public static final int GAME_WEIGHT = 800;
	public static final int GAME_HEIGHT = 600;
		
	Image offScreenImage = null;
	MyTank tk = new MyTank(20,20,true,this);
	MyTank et = new MyTank(500,500,false,this);
	
    Missile m = null;
	
    List<Missile> missiles = new LinkedList<Missile>();
	
	
    public void paint(Graphics g){
		
		g.drawString("已經發射的炮彈數量:" + missiles.size(), 10, 50);
		
		for ( int i=0;i < missiles.size();i++){
			Missile m = missiles.get(i);
			m.hitTank(et);
			if(!m.isLive()) missiles.remove(m);
			else m.draw(g);
		}
		tk.draw(g);		
		et.draw(g);

	}
	
	public void update(Graphics g) {
		if(offScreenImage == null){
			offScreenImage = this.createImage(GAME_WEIGHT, GAME_HEIGHT);
		}
		
		Graphics gOffScreen = offScreenImage.getGraphics();
		Color c = gOffScreen.getColor();
		gOffScreen.setColor(Color.GRAY);
		gOffScreen.fillRect(0, 0, GAME_WEIGHT, GAME_HEIGHT);
		gOffScreen.setColor(c);
		paint(gOffScreen);
		g.drawImage(offScreenImage,0 ,0,null);	
	}

	public void LauchFrame(){
			
		this.setLocation(400, 300);
		this.setSize(GAME_WEIGHT, GAME_HEIGHT);	
		this.setTitle("坦克大戰");
		this.setResizable(false);
		this.addKeyListener(new KeyMonitor());
		this.setBackground(Color.GRAY);
		
		this.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e) {
				System.exit(0);
			}
		});
		this.setVisible(true);
		new Thread(new PaintThread()).start();
	}	
	
	public static void main(String[] args) {
	
		TankClient tc = new TankClient();
		tc.LauchFrame();
	
	}
	
	class PaintThread implements Runnable{

		public void run() {
		
			while(true){
				repaint();
				try {
					Thread.sleep(20);
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}						
		}				
	}

	class KeyMonitor extends KeyAdapter{

		public void keyReleased(KeyEvent e) {
			tk.keyreleased(e);
		}
		
		public void keyPressed(KeyEvent e) {
			tk.keypressed(e);
		}		
	}
}