/*
    unitCircle - a java bean to display a unit circle...
 */

import java.awt.*;
import java.applet.*;

//under jdk 1.1 I could extend component, but in 1.0 I need to
//extend canvas to get that effect...

//public class unitCircle extends Canvas {
//public class unitCircle extends Component {
//public class unitCircle extends Container {
public class unitCircle extends Panel implements Runnable {
    Thread runner = null;

    Color circleCol = Color.black;
    Color hypCol    = Color.black;
    Color sinCol    = Color.red;
    Color cosCol    = Color.blue;


    int circleDelay = 0;

    int x,y =10;
    int mouseX, mouseY=0;
    int width,height = 50;

    int originX = width/2;
    int originY = height/2;

    int offsetX, offsetY = 0;

    int onCircleX, onCircleY = 0;

    float hyp=0;
    float angle=0;  //angle in Radians
    float angleD=0; //angle in Degrees
    int cartX=0, cartY=0;

    double angleSin=0, angleCos=0;


    //Runnable stuff
    public void start(){
        if (runner == null) {
            runner = new Thread(this);
            runner.start();
        }
    }

    public void stop(){
        if (runner != null) {
            runner.stop();
            runner = null;
        }
    }

    public void run(){



        if (circleDelay != 0){
            if (circleDelay < 2) {
                //do it just as quick as your little bits can run
                setAngleD(angleD+1);
            } else {

            while (true) {
    	    	    try { Thread.sleep(circleDelay); }
        		    catch (InterruptedException e){}

                    setAngleD(angleD+1);
                }
            }
        } //else we are in 'normal' event driven mode...I hope
    }

    /////////////////////////////////////////////////////////////
    //Constructors
    unitCircle(){
       //default constructor
       System.out.println("Made a new unitCircle");
       this.locate(x,y);
       this.resize(width,height);
       originX=width/2;
       originY=height/2;
       setAngleD(45);

       repaint();
    }

    unitCircle(int x, int y, int w, int h){
       System.out.println("Made a new unitCircle");
       //this.locate(x,y);

       //try making it a square
       width=Math.min(w, h);
       height=width;

       //width=w;
       //height=h;

       originX=w/2;
       originY=h/2;


       //this.setBounds(x-width,y-height,width,height); //JDK 1.1
       //this.setBounds(x,y,w,h); //JDK 1.1

       this.move(x,y);
       this.resize(w,h);

       //setLayout(new GridLayout(1,1));
       setLayout(null);

       setAngleD((float) 45);
       repaint();
    }

   unitCircle(int x, int y, int w, int h, int d){
       System.out.println("Made a new unitCircle");
       //this.locate(x,y);

       circleDelay = d;
       if (circleDelay < 2) {circleDelay = 1;}

       //try making it a square
       width=Math.min(w, h);
       height=width;

       //width=w;
       //height=h;

       originX=w/2;
       originY=h/2;


       //this.setBounds(x-width,y-height,width,height); //JDK 1.1
       //this.setBounds(x,y,w,h); //JDK 1.1

       this.move(x,y);
       this.resize(w,h);

       //setLayout(new GridLayout(1,1));
       setLayout(null);

       setAngleD((float) 45);
       repaint();
    }


    //end of constructors
    /////////////////////////////////////////////////////////////


    public void init() {

    }


    public boolean handleEvent(Event evt) {
        //
//        System.out.println("In unitCircle handle event x,y "+evt.x+" "+evt.y+" originX,originY="+originX+", "+originY);
       // System.out.println("Target is: "+evt.target);
       // System.out.println("ID: "+evt.id);

        //System.out.println("Mouse_Down: "+evt.MOUSE_DOWN);
        //System.out.println("Mouse_Drag: "+evt.MOUSE_DRAG);

        if (evt.id == evt.MOUSE_DOWN || evt.id == evt.MOUSE_UP || evt.id == evt.MOUSE_DRAG){
//        System.out.println("In unitCircle handle event x,y "+evt.x+" "+evt.y+" originX,originY="+originX+", "+originY);

            mouseX=evt.x;
            mouseY=evt.y;
            angleUpdate();
        }


        return false;
        //return super.handleEvent(evt);
    }



    public void angleUpdate() {
        //Grab position, do stuff from that...

        //convert mouse position to cartesian coordinates.
        cartX = mouseX-originX;
        cartY = originY-mouseY;

        //calculate angle
        hyp     = (float) Math.sqrt(cartX*cartX + cartY*cartY);
        angle   = (float) (Math.asin(cartY/hyp));
        angleD  = (float) Math.abs(angle*(180/Math.PI)); //radians to degrees

        //adjust angle according to quadrant
        //quadrant 1 needs no adjustment
        if (cartX <= 0 && cartY >= 0) angleD= (90-angleD)+ 90;   //quadrant 2
        else
        if (cartX <= 0 && cartY <= 0) angleD= (angleD)+180;     //quadrant 3
        else
        if (cartX >= 0 && cartY <= 0) angleD= (90-angleD)+270; //quadrant 4

        angleD=Math.round(angleD*100)/100;
        angle=(float)(angleD/(180/Math.PI)); //convert back to Radians

        //these two onCircleN=lines are KEY...absolute key!
        //if you want to make the radius line go backwards, or anything else wierd,
        //then just mess with these lines

        //Original
        //onCircleX=(int)(Math.cos(angle)*25)+originX;
        //onCircleY=(int)(-Math.sin(angle)*25)+originY;

        onCircleX=(int)(Math.cos(angle)*originX)+originX;
        onCircleY=(int)(-Math.sin(angle)*originY)+originY;


//System.out.println("onCircleX/Y "+onCircleX+" "+onCircleY);
//System.out.println("mouseX/Y "+mouseX+" "+mouseY);


        repaint();  //this is what makes it happen...

    }


    public void setAngle(float a){
        angle=a;
        angleD  = (float) Math.abs(angle*(180/Math.PI)); //radians to degrees
        onCircleX=(int)(Math.cos(angle)*originX)+originX;
        onCircleY=(int)(-Math.sin(angle)*originY)+originY;

        repaint();
    }

    public void setAngleD(float a){
        angle=(float) (a*Math.PI/180);
        angleD  = a;
//        (float) Math.abs(angle*(180/Math.PI)); //radians to degrees
        onCircleX=(int)(Math.cos(angle)*originX)+originX;
        onCircleY=(int)(-Math.sin(angle)*originY)+originY;

        repaint();
    }


    public float getAngle(){
        return angle;
    }
    public float getAngleD(){
        return angleD;
    }


    public void paint(Graphics g){
        int x,y,w,h = 0;
        Dimension size = this.size(); //getSize in JDK 1.1
        g.setColor(Color.black);
        //x=this.getBounds().x;
        //y=this.getBounds().y;
        w=this.getBounds().width-1;
        h=this.getBounds().height-1;

        //w=width;
        //h=height;
//System.out.println(x+" "+y+" "+w+" "+h);
        //g.drawRect(x+2,y+2,w-10,h-10);

        //////////////////////////////////////////////////////////////
        //a frame
        /*
        g.setColor(Color.lightGray);
        g.fillRect(x,y,w,h);
        g.setColor(Color.black);
        g.drawRect(x,y,w,h);
        g.setColor(Color.red);
        g.drawRect(x+1,y+1,w-2,h-2);
        */

/*
        g.setColor(Color.lightGray);
        g.drawRect(x,y,w,h);

        //////////////////////////////////////////////////////////////
        //the circle
        g.setColor(circleCol);
        g.drawOval(x,y,w,h);

*/
        g.setColor(Color.lightGray);
        g.drawRect(0,0,w,h);

        //////////////////////////////////////////////////////////////
        //the circle

        g.setColor(circleCol);
//        g.drawOval(0,0,w-1,h-1);
        g.drawOval(0,0,w,h);


//////////////////////////////////////////////////////////////
        //draw the triangle
        g.setColor(hypCol);



g.setColor(Color.black);
        g.drawLine(originX,originY,onCircleX,onCircleY);
  //      g.drawLine(originX,originY,onCircleX,onCircleY); //radius line/hypotenuse line


        g.setColor(sinCol);

//System.out.println("originX "+originX+" originY "+originY +"onCircleX "+onCircleX+" onCircleY "+onCircleY);
g.setColor(Color.red);
        g.drawLine(originX,originY,onCircleX,originY);
//        g.drawLine(onCircleX,onCircleY,onCircleX,offsetY); //vertical

        g.setColor(cosCol);

g.setColor(Color.blue);
        g.drawLine(onCircleX,originY,onCircleX,onCircleY); //x axis



    }
}