package org.loon.chair.example6;

import java.awt.Graphics;
import java.awt.Image;

import javax.swing.ImageIcon;
/**
 * 
 * @author chenpeng
 * @email  ceponline@yahoo.com.cn
 * 
 * Loon Framework in Game 
 *
 * 在Example6中開始引入布局的概念
 */
public class GameMap implements Common{

    //設定背景方格默認行數
    private static final int ROW = 15;
    //設定背景方格默認列數
    private static final int COL = 30;
    
    //自動計算地圖大小
    public static final int WIDTH = COL * CS;
    public static final int HEIGHT = ROW * CS;
    
    //設定地圖，通常在rpg類型游戲開發中，以[二維數組]對象為
    //基礎進行地圖處理，用以描繪出X坐標和Y坐標。實際上,即令
    //再華麗的RPG類游戲，都是從這些簡單的X,Y坐標開始的。
    //PS:所謂[數組]，大家可以簡單的理解為即數據的集合，一維數組
    //僅包含X軸，而二維是由X,Y兩個軸組成的，X與Y的交織點，即為
    //一條數據。
    //于Example6中擴充地圖如下
    private int[][] map = {
            {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1},
            {1,0,0,0,0,1,1,1,1,1,0,0,0,0,1,0,0,0,0,0,1,1,1,1,1,0,0,0,0,1},
            {1,0,0,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,1},
            {1,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,1},
            {1,0,0,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,1},
            {1,0,0,0,0,1,1,0,1,1,0,0,0,0,1,0,0,0,0,0,1,1,0,1,1,0,0,0,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
            {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}};

    //設定顯示圖像對象
    private Image floorImage;
    private Image wallImage;
    
    // 游戲所使用面板
    private MyPanel panel;

    public GameMap(MyPanel panel) {
        // 初始化圖像
        loadImage();
    }

    //換算當前image像素到布局
    public static int pixelsToTiles(double pixels) {
        return (int)Math.floor(pixels / CS);
    }
    
    //換算當前布局到image像素
    public static int tilesToPixels(int tiles) {
        return tiles * CS;
    }

    
    //修正Example6中繪制方式，引入地圖坐標偏移計算
    public void draw(Graphics g, int offsetX, int offsetY) {
    	
        int firstTileX = pixelsToTiles(-offsetX);
        //變更X坐標
        int lastTileX = firstTileX + pixelsToTiles(MyPanel.WIDTH) + 1;
        
        //返回最小X偏移值
        lastTileX = Math.min(lastTileX, COL);
        
        
        int firstTileY = pixelsToTiles(-offsetY);
        //變更Y坐標
        int lastTileY = firstTileY + pixelsToTiles(MyPanel.HEIGHT) + 1;
        
        //返回最小Y偏移值
        lastTileY = Math.min(lastTileY, ROW);
    	//在Java或任何游戲開發中，算法都是最重要的一步，本例盡使用
    	//簡單的雙層for循環進行地圖描繪，
            	   for (int i = firstTileY; i < lastTileY; i++) {
                       for (int j = firstTileX; j < lastTileX; j++) {
                    	   // switch作為java中的轉換器，用于執行和()中數值相等
                       	// 的case操作。請注意，在case操作中如果不以break退出
                       	// 執行；switch函數將持續運算到最后一個case為止。
                           switch (map[i][j]) {
                               case 0 : // 地板
                                   g.drawImage(floorImage, tilesToPixels(j) + offsetX, tilesToPixels(i) + offsetY, panel);
                                   break;
                               case 1 : // 墻壁
                                   g.drawImage(wallImage, tilesToPixels(j) + offsetX, tilesToPixels(i) + offsetY, panel);
                                   break;
                           }
                       }
            }
        
    }

    /**
     * 用于判定是否允許移動的發生，被move()函數調用,在Example5開始變更為公有
     * @param x
     * @param y
     * @return
     */
    public boolean isAllow(int x, int y) {
        // 以(x,y)交點進行數據判定，我們都知道，
    	// 在本例中我僅以0作為地板的參數，1作為
    	// 墻的參數，由于我們的主角是[人類]，而
    	// 不是[幽靈]，所以當他要[撞墻]時，我們
    	// 當然不會允許，至少，是我講到劇情的觸發
    	// 以前……
        if (map[y][x] == 1) {
        // 不允許移動時，返回[假]	
            return false;
        }
        
        // 允許移動時時，返回[真]
        return true;
    }

    private void loadImage() {
        ImageIcon icon = new ImageIcon(getClass().getResource("image/floor.gif"));
        floorImage = icon.getImage();
        
        icon = new ImageIcon(getClass().getResource("image/wall.gif"));
        wallImage = icon.getImage();
    }
	
}