//  BallIntersectsRectangeApplet.java  (c) 2006 Kari Laitinen

//  http://www.naturalprogramming.com

//  2006-09-24  File created.
//  2006-09-24  Latest modification.

//  This program works like MovingBallWithMouseApplet.java. 
//  There is an extra rectangle on the screen. The program will find
//  out if you drag a ball so that it intersects with the rectangle.


import java.awt.* ;
import java.awt.event.* ;
import java.awt.geom.* ;

public class BallIntersectsRectangleApplet extends java.applet.Applet               
                                           implements MouseListener,
                                                      MouseMotionListener
{
   int  applet_width, applet_height ;

   Ball  first_ball, second_ball, third_ball  ;

   Rectangle2D.Double  rectangle_on_screen  =  
          new  Rectangle2D.Double( 100, 150, 250, 100 ) ;

   Ball  ball_being_moved  =  null ;

   Point  previous_mouse_position ;

   public void init()
   {
      setBackground( Color.white ) ;

      //  Let's get the size of the applet (defined in .html file)

      applet_width   =  getSize().width ;
      applet_height  =  getSize().height ;

      first_ball   =  new  Ball( applet_width / 2  -  160,
                                 applet_height / 2  - 100,
                                 Color.red ) ;

      second_ball  =  new  Ball( applet_width / 2  -  40,
                                 applet_height / 2  -  100,
                                 Color.green ) ;

      third_ball   =  new  Ball( applet_width / 2  + 80,
                                 applet_height / 2  -  100,
                                 Color.blue ) ;

      addMouseListener(this);
      addMouseMotionListener(this);
   }

   //  The following dummy methods are needed to satisfy listener
   //  interfaces.

   public void mouseMoved( MouseEvent event ) {}
   public void mouseClicked( MouseEvent event ) {}
   public void mouseEntered( MouseEvent event ) {}
   public void mouseExited( MouseEvent event ) {}

   public void mousePressed( MouseEvent event )
   {
      Point mouse_position  =  event.getPoint() ;

      if ( first_ball.contains_point( mouse_position )  )
      {
         ball_being_moved  =  first_ball ;
         ball_being_moved.activate_ball() ;
      }
      else if ( second_ball.contains_point( mouse_position )  )
      {
         ball_being_moved  =  second_ball ;
         ball_being_moved.activate_ball() ;
      }
      else if ( third_ball.contains_point( mouse_position )  )
      {
         ball_being_moved  =  third_ball ;
         ball_being_moved.activate_ball() ;
      }

      previous_mouse_position  =  mouse_position ;

      repaint() ;
   }

   public void mouseReleased( MouseEvent event )
   {
      if ( ball_being_moved  !=  null )
      {
         ball_being_moved.deactivate_ball() ;
         ball_being_moved  =  null ;

         repaint() ;
      }
   }

   public void mouseDragged( MouseEvent event )
   {
      if ( ball_being_moved  !=  null )
      {
         Point new_mouse_position  =  event.getPoint() ;

         int  mouse_movement_x  =  new_mouse_position.x
                                   -  previous_mouse_position.x ;

         int  mouse_movement_y  =  new_mouse_position.y 
                                   -  previous_mouse_position.y ;

         previous_mouse_position  =  new_mouse_position ;

         ball_being_moved.move_this_ball( mouse_movement_x, 
                                          mouse_movement_y ) ;

         repaint() ;
      }
   }


   public void paint( Graphics graphics )
   {
      Graphics2D graphics2D  =  (Graphics2D) graphics ;

      first_ball.draw( graphics ) ;
      second_ball.draw( graphics ) ;
      third_ball.draw( graphics ) ;

      graphics2D.setPaint( Color.cyan ) ;
      graphics2D.fill( rectangle_on_screen ) ;

      
      graphics2D.setPaint( Color.black ) ;
      graphics2D.draw( rectangle_on_screen ) ;
      
      if ( first_ball.intersects_rectangle( rectangle_on_screen ) )
      {
         graphics.drawString( "first_ball intersects rectangle", 20, 20 ) ;
      }

      if ( second_ball.intersects_rectangle( rectangle_on_screen ) )
      {
         graphics.drawString( "second_ball intersects rectangle", 20, 20 ) ;
      }

      if ( third_ball.intersects_rectangle( rectangle_on_screen ) )
      {
         graphics.drawString( "third_ball intersects rectangle", 20, 20 ) ;
      }
   }
}