/*
 * @(#)Rose.java	1.0 1997-11-12
 *
 */

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

/**
 * Draws Paul "Rose" Ernst's modulo arithmetic patterns.
 *
 * @author 	Mark Gilbert
 */

class roseCanvas extends Canvas
{
	int circle_x[];
	int circle_y[];

	int modulus;
	int multiplier;

	Random random;

	public roseCanvas(int modulus, int multiplier)
	{
		super();
		resize(380, 380);
		this.modulus = modulus;
		this.multiplier = multiplier;
		random = new Random(System.currentTimeMillis());
	}

	public roseCanvas()
	{
		this(100, 4);
	}

	public int setMultiplier(int multiplier)
	{
		this.multiplier = multiplier;
		paint(getGraphics());

		return multiplier;
	}

	private int randomInt(int min, int max)
	{
		return min + (int) (random.nextDouble() * (max - min + 1));
	}

	public int randomizeModulus()
	{
		return setModulus(randomInt(3, 1000));
	}

	public int randomizeMultiplier()
	{
		return setMultiplier(randomInt(1, modulus));
	}

	public int setModulus(int modulus)
	{
		this.modulus = modulus;
		paint(getGraphics());

		return modulus;
	}

	void connectPoints(Graphics g, int p1, int p2)
	{
		g.drawLine(circle_x[p1], circle_y[p1], circle_x[p2], circle_y[p2]);
	}

	public void paint(Graphics g)
	{
		Rectangle area = bounds();

		int width = area.width;
		int height = area.height;

		circle_x = new int[modulus];
		circle_y = new int[modulus];

		int origin_x = width / 2;
		int origin_y = height / 2;

		int radius = Math.min(width, height) / 2 - 5;

		for (int i=0 ; i<modulus ; i++)
		{
			circle_x[i] = origin_x + (int) Math.round((double) radius * Math.cos((double) i / (double) modulus * 2 * Math.PI));
			circle_y[i] = origin_y + (int) Math.round((double) radius * Math.sin((double) i / (double) modulus * 2 * Math.PI));
		}

		g.clearRect(0, 0, width, height);

		for (int i=0 ; i<modulus-1 ; i++)
		{
			connectPoints(g, i, i+1);

			int drawTo = (int) (((long) i * (long) multiplier % (long) modulus + (long) modulus) % (long) modulus);
			connectPoints(g, i, drawTo);
		}
		connectPoints(g, modulus-1, 0);
	}
}

public class Rose extends Applet
{
	private Button drawButton;
	private TextField modulusField;
	private TextField multiplierField;
	private Button randomizeModulus;
	private Button randomizeMultiplier;
	private roseCanvas canvas;
	private Panel controls;

	final int defaultModulus = 400;
	final int defaultMultiplier = 4;

	int modulus = defaultModulus;
	int multiplier = defaultMultiplier;

	public void init()
	{
		Panel modulusPanel = new Panel();
		modulusPanel.add(new Label("Modulus"));
		modulusField = new TextField(Integer.toString(defaultModulus), 10);
		modulusPanel.add(modulusField);
		randomizeModulus = new Button("Randomize");
		modulusPanel.add(randomizeModulus);

		Panel multiplierPanel = new Panel();
		multiplierPanel.add(new Label("Multiplier"));
		multiplierField = new TextField(Integer.toString(defaultMultiplier), 10);
		multiplierPanel.add(multiplierField);
		randomizeMultiplier = new Button("Randomize");
		multiplierPanel.add(randomizeMultiplier);

		Panel drawPanel = new Panel();
		drawButton = new Button("Draw");
		drawPanel.add(drawButton);

		canvas = new roseCanvas(defaultModulus, defaultMultiplier);

		controls = new Panel();
		controls.setLayout(new GridLayout(3, 1));

		controls.add(modulusPanel);
		controls.add(multiplierPanel);
		controls.add(drawPanel);

		this.setLayout(new BorderLayout(15, 15));
		this.add("North", canvas);
		this.add("South", controls);

		resize(390, 500);
	}

	public void paint(Graphics g)
	{
		modulus = canvas.setModulus(modulus);
		multiplier = canvas.setMultiplier(multiplier);
	
		modulusField.setText(Integer.toString(modulus));
		multiplierField.setText(Integer.toString(multiplier));
	}

	void getValues()
	{
		modulus = Integer.parseInt(modulusField.getText());
		multiplier = Integer.parseInt(multiplierField.getText());
	}

	public boolean action(Event event, Object arg)
	{
		if (event.target == drawButton || event.target == modulusField || event.target == multiplierField)
		{
			getValues();
			paint(getGraphics());
			return true;
		}
		else if (event.target == randomizeModulus)
		{
			modulus = canvas.randomizeModulus();
			paint(getGraphics());
			return true;
		}
		else if (event.target == randomizeMultiplier)
		{
			multiplier = canvas.randomizeMultiplier();
			paint(getGraphics());
			return true;
		}
		else
		{
			return super.action(event, arg);
		}
	}
/*
	public static void main(String args[])
	{
		Frame frame = new 
	}
*/
}