// (c) 1998 Ekkehard Kraemer (ekraemer@pluto.camelot.de)

import java.awt.*;
import java.io.*;
import java.util.*;
import java.net.*;

/**
 * Sorry, not documented yet.
 * <p>
 * <a href="Field.txt">Source</a>
 */
class Field
{
    Field(BojngInterface bojng,URL urlBase,Canvas canvas)
    {
	this.bojng=bojng;
	this.urlBase=urlBase;
	items=new Item[height][width];
    }

    synchronized void clear()
    {
	itemCnt=0;
	freeBlocks.removeAllElements();
	timedItems.removeAllElements();
	for (int y=0; y<height; y++)
	    for (int x=0; x<width; x++)
	    {
		items[y][x]=null;
		if (y<width-3)
		    freeBlocks.addElement(new Point(x,y));
	    }
    }

    synchronized String loadLevel(int n)
    {
	String name="unknown level";
	try
	{
	    clear();

	    System.err.println("Loading level "+n);
	    bojng.msg("Loading level...");

	    String fn="levels/level";
	    if (n<10) fn=fn+"0";
	    fn=""+fn+n+".data";
	    URL file=new URL(urlBase,fn);
	    InputStream is=file.openStream();
	    DataInputStream dis=new DataInputStream(is);
	    
	    name=dis.readLine();
	    bojng.msg(name);
	    
	    String misc=dis.readLine();
	    for (int y=0; y<height; y++)
	    {
		String line=dis.readLine();
		if (line==null) break;
		System.err.println(line);
		for (int x=0; x<width; x++)
		{
		    char chr=line.charAt(x);
		    Item i=createBlock(chr);
		    if (i!=null) placeItem(x,y,i);
		}
	    }
	} catch (Exception e) { e.printStackTrace(System.err); }

	bojng.repaint();

	return name;
    }

    Item createBlock(char chr)
    {
	switch (chr)
	{
	case '.': break;

	case '1': 
	case '2': 
	case '3': 
	case '4': 
	case '5':
	    Item i=new Block(bojng,Images.block[chr-'1'],Item.NONE); 
	    i.delay=chr-'0';
	    return i;
	    
	case 'B':
	    return new Block(bojng,Images.bullet,Item.BULLETS); 
	case 'w':
	    return new Block(bojng,Images.wall,Item.WALL); 
	case 'm':
	    return new Block(bojng,Images.triple,Item.TRIPLE);
	case '<':
	    return new Block(bojng,Images.shrink,Item.SHRINK);
	case '>':
	    return new Block(bojng,Images.grow,Item.GROW);
	case 'L':
	    return new Block(bojng,Images.newball,Item.NEWBALL);
	case 'X':
	    return new Block(bojng,Images.bomb,Item.BOMB);
	case 'H':
	    return new Block(bojng,Images.teleport,Item.TELEPORT);

	case 'r':
	    return new Block(bojng,Images.block[0],Item.NONE); 
	case 'g':
	    return new Block(bojng,Images.block[1],Item.NONE); 
	case 'b':
	    return new Block(bojng,Images.block[2],Item.NONE); 
	case 't':
	    return new Block(bojng,Images.block[3],Item.NONE); 
	case '0':
	    return new Block(bojng,Images.block[4],Item.NONE); 
	case 'y':
	    return new Block(bojng,Images.block[5],Item.NONE); 
	case 'p':
	    return new Block(bojng,Images.block[6],Item.NONE); 
	    
	default:
	    return new Block(bojng,Images.block[6],Item.UNKN); 
	}

	return null;
    }

    // setzt + initialisiert ein Item
    synchronized void placeItem(int x,int y,Item i)
    {
	if (items[y][x]==null) 
	{
	    if (i.count) itemCnt++;	    
	    for (Enumeration e=freeBlocks.elements(); e.hasMoreElements(); )
	    {
		Point p=(Point)(e.nextElement());
		if (p.x==x && p.y==y)
	        {
		    freeBlocks.removeElement(p);
		    break;
		}
	    }
	}
	items[y][x]=i;
	i.init(x,y,bojng._blockwidth(),bojng._blockheight());	
    }

    synchronized public boolean removeItem(int x,int y)
    {
	Item i=items[y][x];
	if (i==null) return false;
	freeBlocks.addElement(new Point(x,y));
	timedItems.removeElement(i);
	items[y][x]=null;
	if (i.count) itemCnt--;
	if (itemCnt<1) return true;
	return false;
    }

    synchronized void explodeAllBlocks()
    {
	for (int y=0; y<height; y++)
	    for (int x=0; x<width; x++)
	    {
		Item i=items[y][x];
		if (i!=null) i.hit();
	    }
    }

    synchronized Item getItem(int x,int y)
    {
	if (x<0 || y<0 || x>=width || y>=height) return null;
	return items[y][x];
    }

    synchronized Point getFreeBlock()
    {
	if (freeBlocks.size()==0) return null;
	return (Point)(freeBlocks.elementAt(bojng.posRand(freeBlocks.size())));
    }

    synchronized void placeRandom(int ms)
    {
	Point p=getFreeBlock();
	if (p==null) return;

	Item i=null;
	switch (bojng.posRand(1))
	{
	    //case 0: i=new Block(bojng,prod.getImage('r'),Item.NONE); break;
	}

	if (i!=null) 
	{
	    placeItem(p.x,p.y,i);
	    timedItems.addElement(i);
	    i.ageLeft=7000/ms;
	    bojng.msg("Get it!");
	}
    }

    synchronized void tick()
    {
	for (Enumeration e=timedItems.elements(); e.hasMoreElements(); )
	{
	    Item i=(Item)(e.nextElement());
	    i.ageLeft--;
	    if (i.ageLeft<1)
	    {
		i.hit();
		timedItems.removeElement(i);
		bojng.msg("Too late...");
	    }
	}
    }

    final int width=9,height=17; // Number of blocks (0,0)=links oben
    Item[][] items;
    Vector freeBlocks=new Vector();
    Vector timedItems=new Vector();
    int itemCnt;
    BojngInterface bojng;
    URL urlBase;
    Random rand=new Random();    
}