//RandomLines.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class RandomLines extends JApplet implements ActionListener {
    
    private JLabel linesLabel, equalLengthLabel, maxLengthLabel;
    private JTextField linesField, equalLengthField, maxLengthField;
    private JButton againButton;

    public void init() {

      Container container = getContentPane();  
      container.setLayout( new FlowLayout() ); 

      linesLabel = new JLabel( "Number of lines" );
      linesField = new JTextField( 4 );
      container.add( linesLabel );
      container.add( linesField );

      equalLengthLabel = new JLabel( "All equal length?" );
      equalLengthField = new JTextField( 4 );
      container.add( equalLengthLabel );
      container.add( equalLengthField );

      maxLengthLabel = new JLabel( "Max. length" );
      maxLengthField = new JTextField( 4 );
      container.add( maxLengthLabel );
      container.add( maxLengthField );

      againButton = new JButton( "Again! Again!" );
      container.add( againButton );

      againButton.addActionListener( this );


    }


    public void actionPerformed( ActionEvent event ) {
	if ( event.getSource() == againButton )
	    repaint();
    }


    public void paint( Graphics g )
    {
       int x1, y1, x2, y2;
       double angle;
       int lines;
       int length;
       int maxLength;
       boolean equalLengthLines;

       super.paint( g );
       
       //random point (x1,y1)  then random point in circle of maxLength radius
       //around it

       //if equalLengthLines is true:
       length =    Integer.parseInt(maxLengthField.getText());
       maxLength = Integer.parseInt(maxLengthField.getText());

       lines = Integer.parseInt(linesField.getText());

       if (equalLengthField.getText().equals("yes"))
	   equalLengthLines = true;
       else
	   equalLengthLines = false;

       for (int i=1; i<=lines; i++) {
	   x1 = (int)(Math.random() * getWidth());
	   y1 = (int)(Math.random() * getHeight());
	   angle = Math.random() * 2 * Math.PI;    //radians
	   if (!equalLengthLines)
	       length = (int)(Math.random() * maxLength);
	   x2 = (int)(Math.cos(angle) * length + x1);
	   y2 = (int)(Math.sin(angle) * length + y1);
 	   
	   g.drawLine(x1,y1,x2,y2);
       }
       

       /*
       //test if draws to edge or draws nothing
       //draws to edges!
       g.drawLine(10,10,-10,-10);
       g.drawLine(700,100,900,100);
       */
   }
}