import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.awt.geom.*;
import javax.swing.Timer;
import javax.swing.*;


public class Gameboard extends JPanel
{
    Timer myTimer;
    int wd, ht;
    Robot  robot;
    ArrayList<Ball> balls = new ArrayList<Ball>();
    ArrayList<Ball> fixedPts = new ArrayList<Ball>();
    ArrayList<WallSeg> segs = new ArrayList<WallSeg>();
    ArrayList<Collision> collisions = new ArrayList<Collision>();
    Scanner sc = new Scanner(System.in);
    boolean done = false;
    double simtime = 0.0;

    
    Gameboard()
    {
	Ball b;
	robot = new Robot(50,460,24,23,new Color(180,180,255));
	robot.theta = -45;
	int wd = 740;
	int ht = 500;

	make_area1();

	Color [] colors = {Color.RED, Color.GREEN, Color.BLUE, Color.MAGENTA, Color.YELLOW};
	String [] names = {"red","green","blue","magneta","yellow"};
	for (int k=0; k<5; k++) {
		b = new Ball();
		b.randomize(20.0,wd,ht);
		while (intersect_world(b)) b.randomize(10.0,wd,ht);
		b.color = colors[k];
		b.set_name(names[k]);
		balls.add(b);
	}

    }

    void make_area1()
    {
	Ball pt1, pt2, pt3, pt4, pt5;
	// room boundaries
	pt1 = new Ball(10, 10);
	pt2 = new Ball(730, 10);
	pt3 = new Ball(730, 490);
	pt4 = new Ball(10, 490);
	segs.add(new WallSeg(pt1,pt2));
	segs.add(new WallSeg(pt2,pt3));
	segs.add(new WallSeg(pt3,pt4));
	segs.add(new WallSeg(pt4,pt1));
	// obstructions
	pt1 = new Ball(540, 300);
	fixedPts.add(pt1);
	pt2 = new Ball(540, 160);
	fixedPts.add(pt2);
	pt3 = new Ball(300, 160);
	fixedPts.add(pt3);
	pt4 = new Ball(300, 390);
	fixedPts.add(pt4);
	pt5 = new Ball(540, 390);
	fixedPts.add(pt5);
	segs.add(new WallSeg(pt1,pt2));
	segs.add(new WallSeg(pt2,pt3));
	segs.add(new WallSeg(pt3,pt4));
	segs.add(new WallSeg(pt4,pt5));

	pt1 = new Ball(200, 490);
	pt2 = new Ball(200, 200);
	segs.add(new WallSeg(pt1,pt2));
	pt3 = new Ball(100, 200);
	segs.add(new WallSeg(pt2,pt3));
	fixedPts.add(pt2);
	fixedPts.add(pt3);
    }

   public boolean intersect_world(Ball bt)
   {
        for (Ball b: balls) {
	   if (b.dist(bt)<50) return true;
	}
	for (WallSeg seg: segs) {
		if (seg.dist(bt)<0) return true;
	}
	return false;
   }


    public void update1()
    {
	wd = getWidth();
	ht = getHeight();
	double tstep = 0.05;
	double tmin = 1.0;
	robot.updateVelocity();
	double t = robot.intersect_window(wd,ht);
	if (t<tmin) tmin = t;
	for (WallSeg ws: segs) {
	    t = ws.intersect(robot);
	    if (t<tmin) tmin = t;
 	}
	for (Ball b: fixedPts) {
	    t = b.intersect(robot);
	    if (t<tmin) tmin = t;
        }
	if (tmin<=tstep) {
                robot.move(tmin);
		robot.setVelocity(0,0);
	}
	else robot.move(tstep);
	simtime += tstep;
	repaint();
	if (done) {
	   stopAnimation();
	   System.out.format("Task completed in %g time units%n",simtime);
        }
    }

    public boolean check_distance()
    {
	double dist;
	boolean flag = false;
	int nballs = balls.size();
	for (int i=0; i<nballs-1; i++) {
	    for (int j=i+1; j<nballs; j++) {
		Ball b1 = balls.get(i);
		Ball b2 = balls.get(j);
		dist = b1.dist(b2);
		if (dist<-0.01) {
			System.out.println("dist " + dist + " " + b1 + b2);
			double dx = b2.px-b1.px;
			double dy = b2.py-b1.py;
			System.out.println( b1.info());
			System.out.println( b2.info());
			System.out.println("dx " + dx + " dy " + dy);
			System.out.println("sep " + Math.hypot(dx,dy) + " radius " + (b1.radius+b2.radius));
			flag = true;
		}
	    }

	}
	return flag;
    }

    void pause()
    {
	stopAnimation();
	repaint();
	sc.nextLine();
	startAnimation();
    }

private Collision clast = null;

    public void update2()
    {
	wd = getWidth();
	ht = getHeight();
	double tstep, tmore;
	tstep = 1.0;
	tmore = tstep;
	while (tmore>0.0) {
	    update_collision_list(tmore);
	    if (collisions.size()>0) {
		java.util.List<Collision> list = collisions; 
		Collections.<Collision>sort(list);
		Collision c = collisions.get(0);
		tstep = c.timestep;
		tmore = tmore - tstep;
		boolean flag = check_distance();

		if (flag) {
			if (clast!=null) System.out.println("last collision " + clast);
			for (Collision ct: collisions) System.out.println(ct);
			pause();
		}
		clast = c;

		
		for (Ball ball: balls) ball.move(tstep);
		c.update_velocity();
	    }
	    else {
		tstep = tmore;
		tmore = 0.0;
		for (Ball ball: balls) ball.move(tstep);
	    }
	}
	simtime += tstep;
	repaint();
    }

    public void update_collision_list(double tstep)
    {
	Collision c;
	collisions.clear();
	double t;
	for (Ball ball: balls)	{
	    t = ball.intersect_window_vertical(wd);
	    if (t>0.0 && t<tstep) collisions.add(new Collision(t,ball,1));
	    t = ball.intersect_window_horizontal(ht);
	    if (t>0.0 && t<tstep) collisions.add(new Collision(t,ball,2));

	    for (WallSeg seg: segs) {
		t = seg.intersect(ball);
		if (t>0.0 && t<tstep) collisions.add(new Collision(t,ball,seg));

	    for (Ball pt: fixedPts) {
		t = ball.intersect(pt);
		if (t>0.0 && t<tstep) {
			c = new Collision(t,ball,pt);
			collisions.add(c);
			c.ndx = -2;
		}
	    }
	}
	int nballs = balls.size();
	for (int i=0; i<nballs-1; i++) {
	    for (int j=i+1; j<nballs; j++) {
		Ball b1 = balls.get(i);
		Ball b2 = balls.get(j);
		t = b1.intersect(b2);
		if (t>0.0 && t<tstep) collisions.add(new Collision(t,b1,b2));
	    }
	}
	//label.setText(wallseg.str);
    }	
}
    

    public void paintComponent(Graphics g)
    {
	super.paintComponent(g);
	// draw grid
	g.setColor(Color.RED);
	int n;
	int w = 80;
	for (n=0; n<7; n++) {
	    g.drawLine(10,10+n*w,10+9*w,10+n*w);
	}
	for (n=0; n<10; n++) {
	    g.drawLine(10+n*w,10,10+n*w,10+6*w);
        }
	// draw walls
	for (WallSeg ws: segs) ws.draw(g);
	for (Ball b: fixedPts) b.draw(g);
	// draw balls
	for (Ball b: balls) b.draw(g);
	// draw robot
	robot.draw(g);
    }

    
    public void startAnimation()
    {
	if (myTimer == null)
	{
	    myTimer = new Timer(50,new TimerHandler() );
	    myTimer.start();
	}
	else if (!myTimer.isRunning()) myTimer.restart();
    }

    public void stopAnimation()
    {
	myTimer.stop();
    }

    private class TimerHandler implements ActionListener
    {
	public void actionPerformed(ActionEvent actionevent)
	{
	    update2();
	}
    }
}