// Read in circle descriptions and draw them -- but don't draw them if
// they overlap any of the circles that have already been drawn
//
// 
// A.B. Maccabe
// March 2005
// The University of New Mexico
//
// This program illustrates:
//  1) how to use the Space class, and
//  2) the use of a Vector to keep track of a set of objects
//
// Each circle is defined by three doubles: the x and y coordinates of
// the center and the radius.  The inout terminates when a circle with
// a non positive radius is entered.

import ann.easyio.*;			// Keyboard, Screen, ...

import java.lang.*;
import java.util.*;

class DrawCircles extends Object
{
    public static void main(String [] args) 
    {
	Space sp = new Space( 100, 100 ); // construct a canvas
	Keyboard theKeyboard = new Keyboard();
	Screen theScreen = new Screen();

	// we need to keep track of the circles that we have already drawn
	Vector circlesDrawn = new Vector();

	// read 
	for( ; ; ) {
	    // read in the next circle
	    double x, y, r;
	    x = theKeyboard.readDouble();
	    y = theKeyboard.readDouble();
	    r = theKeyboard.readDouble();

	    // check for the termination condition
	    if( r <= 0 ) break;	// all done

	    // it's a real circle
	    Circle thisCircle = new Circle( r, x, y );

	    // now, see if it overlaps with any of the circles already drawn
	    boolean overlap = false; // no overlaps so far
	    for( Iterator i = circlesDrawn.iterator(); 
		 i.hasNext() && !overlap ; ) {
		Circle nextCircle = (Circle) i.next();
		overlap = thisCircle.overlap( nextCircle );
		theScreen.println( "overlap = " + overlap + " " +
				   thisCircle + " " + nextCircle );
	    }

	    // if the cicle doesn't overlap any of the others, draw it and 
	    // add it to the set of drawn circles
	    if( !overlap ) {
		sp.drawCircle( x, y, r );
		circlesDrawn.add( thisCircle );
	    }
	}
	theScreen.println( "Done reading circles." );
    }
}