import java.awt.*;
import java.applet.Applet;
import java.util.*;

public class MapWalk extends Applet implements Runnable{
	Thread th;
	Updater udr;
	Node[] nodes;
	Walker[] walkers;
	BakGrad bakGrad;
	Checkbox wire, ball;

	public void init(){
		udr = new Updater(this);
		Dimension walkerSz = new Dimension(32, 32);
		makeMap(walkerSz);

		EzImg ez = new EzImg(this);
		walkers = new Walker[4];
		int z = 20;
		for(int i=0;i<walkers.length;i++){
			Color col = Rnd.color();
			Image img = ez.maru(walkerSz, col);
			img = ez.alphaImg(img);
			int speed = Rnd.get(3, 10);
			walkers[i] = new Walker(img, udr, z, nodes[0], speed);
		}
		bakGrad = new BakGrad(udr, size());
		udr.add(bakGrad, 0);

		add(wire = new Checkbox("wire"));
		add(ball = new Checkbox("ball"));

		th = new Thread(this);
		th.start();
	}
	void makeMap(Dimension walkerSz){
		nodes = new Node[5];
		int i;
		int z = 12;
		for(i=0;i<nodes.length;i++){
			Rectangle r = new Rectangle(size());
			r.grow(-walkerSz.width/2, -walkerSz.height/2);
			nodes[i] = new Node(r, udr);
			udr.add(nodes[i], z);
		}
		z = 10;
		for(i=0;i<nodes.length;i++){
			for(int j=i+1;j<nodes.length;j++){
				udr.add(new Road(nodes[i], nodes[j]), z);
			}
		}
	}
	public void run(){
		while(th.isAlive()){
			try{
			  th.sleep(100);
			}catch(InterruptedException e){}
			work();
		}
	}
	void work(){
		int i;
		if(ball.getState()){
			for(i=0;i<walkers.length;i++){
				walkers[i].walk();
			}
		}
		if(wire.getState()){
			for(i=0;i<nodes.length;i++){
				nodes[i].move();
			}
		}
		bakGrad.update();
		repaint();
	}
	public void update(Graphics g){
		udr.update(g);
	}
}
class Walker implements Drawer{
	Image img;
	Dimension sz;
	Updater udr;

	Road road;
	double posi;
	double speed;
	boolean revdir;

	public Walker(Image img, Updater udr, int z, Node node, double speed){
		this.img = img;
		sz = EzImg.size(img);
		this.udr = udr;
		udr.add(this, z);
		this.speed = speed;
		turn(node, null);
	}	
	public void walk(){
		Rectangle r = rect();
		boolean chk = false;
		posi += revdir ? -speed : speed;
		boolean onLoad = 0<posi && posi<road.len();
		if(!onLoad){
			Node n = revdir ? road.s : road.e;
			turn(n, road);
		}
		udr.set(r.union(rect()));
	}
	void turn(Node n, Road avoid){
		do{
			int i = Rnd.get(0, n.rlst.size()-1);
			road = (Road)n.rlst.elementAt(i);
		}while(road==avoid);
		revdir = road.revdir(n);
		posi = revdir ? road.len() : 0;
	}
	Point place(){
		return road.place(posi);
	}
	Rectangle rect(){
		Rectangle r = new Rectangle(place(), sz);
		r.translate(-sz.width/2, -sz.height/2);
		return r;
	}

	boolean done;
	public void draw(Graphics g, Rectangle r){
		if(done) return;
		Rectangle rr = rect();
		g.drawImage(img, rr.x, rr.y, null);
		done = true;
	}
	public void begin(){
		done = false;
	}
	public void end(){}
}
class Node implements Drawer{
	public Point p;
	public Vector rlst;
	Updater udr;
	MySin sx, sy;
	GradCol gcol;

	public Node(Rectangle area, Updater udr){
		rlst = new Vector();
		this.udr = udr;
		sx = new MySin(area.x,area.x+area.width,Rnd.get(100,200),-1);
		sy = new MySin(area.y,area.y+area.height,Rnd.get(100,200),-1);
		p = new Point(sx.get(),sy.get());
		gcol = new GradCol();
	}
	public void add(Road r){
		rlst.addElement(r);
	}
	public double len(Node o){
		return Pts.len(o.p, p);
	}

	public void move(){ // override class Mov
		p = new Point(sx.get(),sy.get());
		udr.setAll(); // (^^;;;
	}

	boolean done;
	public void draw(Graphics g, Rectangle r){
		if(done) return;
		g.setColor(gcol.get());
		Dimension sz = new Dimension(16,16);
		Rectangle rr = new Rectangle(p, sz);
		rr.translate(-rr.width/2,-rr.height/2);
		Rects.fill(g, rr);
		done = true;
	}
	public void begin(){
		done = false;
	}
	public void end(){}
}
class Road implements Drawer{
	public Node s, e;
	static GradCol gcol = new GradCol();

	public Road(Node s, Node e){
		this.s = s;
		this.e = e;
		s.add(this);
		e.add(this);
	}
	public double len(){
		return s.len(e);
	}
	public boolean revdir(Node s){
		return s!=this.s;
	}
	Point place(double posi){
		double ratio = posi / len();
		return new Point(
			(int)(e.p.x * ratio + s.p.x * (1-ratio)),
			(int)(e.p.y * ratio + s.p.y * (1-ratio))
		);
	}

	boolean done;
	public void draw(Graphics g, Rectangle r){
		if(done) return;
		g.setColor(gcol.get());
		Pts.line(g, s.p, e.p);
		done = true;
	}
	public void begin(){
		done = false;
	}
	public void end(){}
}
class BakGrad implements Drawer{
	GradCol gcol;
	Color col;
	Updater udr;
	Dimension sz;

	public BakGrad(Updater udr, Dimension sz){
		gcol = new GradCol();
		this.udr = udr;
		this.sz = sz;
	}
	public void update(){
		col = gcol.get();
		udr.setAll(); // (^^;;;
	}

	boolean done;
	public void draw(Graphics g, Rectangle r){
		if(done) return;
		g.setColor(col);
		Rects.fill(g, new Rectangle(sz));
		done = true;
	}
	public void begin(){
		done = false;
	}
	public void end(){}
}

// EOF