package book.mutimedia.greadsnake;

import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
/**
 * 	蛇的控制類(lèi)，負(fù)責(zé)控制貪吃蛇。MVC中的Control
 */
public class SnakeControl implements KeyListener{ 
    
	// 待控制的貪吃蛇的模型對(duì)象
    private SnakeModel model;
    // 貪吃蛇的試圖對(duì)象
    private SnakeView view;
    
    // 貪吃蛇的運(yùn)行區(qū)域大小
    private int district_maxX;
    private int district_maxY;    
    
    // 默認(rèn)構(gòu)造方法
    public SnakeControl(){
        this.district_maxX = 30;
        this.district_maxY = 40;
        init();
    }
    
    // 帶參數(shù)的構(gòu)造方法
    public SnakeControl(int maxX, int maxY) {
    	// 判斷參數(shù)是否合法，這里定義了蛇運(yùn)行區(qū)域最大和最小范圍
        if ((10 < maxX) && (maxX < 100) && (10 < maxY) && (maxY < 100)){
            this.district_maxX = maxX;
            this.district_maxY = maxY;
        } else {
        	System.out.println("初始化參數(shù)錯(cuò)誤，用默認(rèn)參數(shù)構(gòu)造對(duì)象！");
            this.district_maxX = 30;
            this.district_maxY = 40;
        }
        init();
    }
    
    // 初始化
    private void init(){
    	// 創(chuàng)建貪吃蛇模型
        this.model = new SnakeModel(district_maxX, district_maxY);
        // 創(chuàng)建貪吃蛇視圖
        this.view = new SnakeView(district_maxX, district_maxY, 500, 200);
        // 為模型添加試圖，當(dāng)模型改變時(shí)，能夠通知到試視圖
        this.model.addObserver(this.view);
        // 為視圖添加鍵盤(pán)事件處理器
        this.view.addKeyListener(this);
        // 蛇開(kāi)始運(yùn)行
        (new Thread(this.model)).start();
    }
    
    // 處理鍵盤(pán)事件
    public void keyPressed(KeyEvent e) {
        int keyCode = e.getKeyCode();
        // 只有在貪吃蛇處于運(yùn)行狀態(tài)下，才處理的按鍵事件
        if (model.isRunning()) {
            switch (keyCode) {
            	// 處理蛇運(yùn)行的方向
                case KeyEvent.VK_UP:
                    model.changeDirection(SnakeModel.UP);
                    break;
                case KeyEvent.VK_DOWN:
                    model.changeDirection(SnakeModel.DOWN);
                    break;
                case KeyEvent.VK_LEFT:
                    model.changeDirection(SnakeModel.LEFT);
                    break;
                case KeyEvent.VK_RIGHT:
                    model.changeDirection(SnakeModel.RIGHT);
                    break;
                // 處理蛇運(yùn)行的速度
                case KeyEvent.VK_ADD:
                case KeyEvent.VK_PAGE_UP:
                    model.speedUp();
                    break;
                case KeyEvent.VK_SUBTRACT:
                case KeyEvent.VK_PAGE_DOWN:
                    model.speedDown();
                    break;
                // 控制蛇的暫停與恢復(fù)
                case KeyEvent.VK_SPACE:
                case KeyEvent.VK_P:
                    model.changePauseState();
                    break;
                default:
            }
        }

        // 控制游戲的重新開(kāi)始
        if (keyCode == KeyEvent.VK_R || keyCode == KeyEvent.VK_S 
        		|| keyCode == KeyEvent.VK_ENTER) {
            model.reset();
        }
        // 停止游戲
        if (keyCode == KeyEvent.VK_Q) {
            model.setRunning(false);
        }
    }

    public void keyReleased(KeyEvent e) {
    	// do nothing
    }
    public void keyTyped(KeyEvent e) {
    	// do nothing
    }
}