//  MouseDemoApplet.java  (c) Kari Laitinen

//  http://www.naturalprogramming.com/

//  2007-02-25  File created.
//  2009-11-05  Last modification

//  This program demonstrates how a Java program can react to
//  mouse events. The following is the mechanism to react to
//  mouse events:
//   -- this program implements the MouseListener and MouseMotionListener
//      interfaces which specify a set of methods that are called
//      automatically by the program execution system
//   -- in the init() method the MouseDemoPanelApplet object informs the
//      program execution system that it will listen to mouse events
//   -- this program provides either dummy or non-dummy implementations
//      for all the methods specified in the interfaces

//  This program also shows how to find out which mouse button was used
//  and whether the Ctrl or Shift key was pressed simulaneously with
//  a mouse button.

//  This is a JPanel-based applet which means that all functionality is
//  built into a class that is derived from class JPanel. In the applet
//  class we simply attach a JPanel-based object to the applet.
//  JPanel-based applets are equipped with automatic double buffering
//  which means that the flickering of the screen is minimized.


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

class MouseDemoPanel extends JPanel
                     implements MouseListener, MouseMotionListener
{
   int current_mouse_position_x  =  340 ;
   int current_mouse_position_y  =  120 ;

   boolean left_mouse_button_is_down    =  false ;
   boolean middle_mouse_button_is_down  =  false ;
   boolean right_mouse_button_is_down   =  false ;

   boolean control_or_shift_key_is_down  =  false ;

 
   public MouseDemoPanel()
   {
      setBackground( new Color( 0xC8, 0xDC, 0xFF ) ) ; // Light blueish

      addMouseListener( this ) ;
      addMouseMotionListener( this ) ;
   }

   //  The following dummy methods are needed
   //  to fully implement the mouse listener interfaces.
   public void mouseClicked( MouseEvent event ) {}
   public void mouseEntered( MouseEvent event ) {}
   public void mouseExited( MouseEvent event ) {}


   //  The following method will be called automatically by the
   //  program execution system when a mouse button is pressed
   //  down. The MouseEvent object that is received as a parameter
   //  contains information related to the mouse event.

   public void mousePressed( MouseEvent event )
   {
      current_mouse_position_x = event.getX() ;
      current_mouse_position_y = event.getY() ;

      if ( event.getButton()  ==  MouseEvent.BUTTON1 )
      {
         left_mouse_button_is_down  =  true ;
      }
      else if ( event.getButton()  ==  MouseEvent.BUTTON2 )
      {
         middle_mouse_button_is_down  =  true ;
      }
      else if ( event.getButton()  ==  MouseEvent.BUTTON3 )
      {
         right_mouse_button_is_down  =  true ;
      }

      if ( event.isControlDown() ==  true  ||
           event.isShiftDown()   ==  true )
      {
         control_or_shift_key_is_down  =  true ;
      }
      else
      {
         control_or_shift_key_is_down  =  false ;
      }

      repaint() ;
   }

   //  The mouseMoved() method is called when the mouse is moved without
   //  pressing its buttons.

   public void mouseMoved( MouseEvent event )
   {
      current_mouse_position_x = event.getX() ;
      current_mouse_position_y = event.getY() ;

      repaint();
   }

   //  The mouseDragged() method is called when the mouse is moved while
   //  one of its buttons is pressed down.

   public void mouseDragged( MouseEvent event )
   {
      current_mouse_position_x = event.getX() ;
      current_mouse_position_y = event.getY() ;

      repaint();
   }

   public void mouseReleased( MouseEvent event )
   {
      if ( event.getButton()  ==  MouseEvent.BUTTON1 )
      {
         left_mouse_button_is_down  =  false ;
      }
      else if ( event.getButton()  ==  MouseEvent.BUTTON2 )
      {
         middle_mouse_button_is_down  =  false ;
      }
      else if ( event.getButton()  ==  MouseEvent.BUTTON3 )
      {
         right_mouse_button_is_down  =  false ;
      }

      repaint();
   }

   public void paintComponent( Graphics graphics )
   {
      super.paintComponent( graphics ) ;

      //  The following statements draw a body for the mouse.
      //  The mouse body is a large oval (ellipse).

      graphics.setColor( Color.DARK_GRAY ) ;

      graphics.fillOval( current_mouse_position_x - 80,
                         current_mouse_position_y - 30,
                         160, 210 ) ;

      //  The mouse buttons will be drawn with a different color
      //  if either the Ctrl or the Shift key is pressed down.

      if ( control_or_shift_key_is_down  ==  true )
      {
         graphics.setColor( Color.MAGENTA ) ;
      }
      else
      {
         graphics.setColor( Color.YELLOW ) ;
      }


      //  We'll draw only those mouse buttons that are being pressed.
      //  Small ellipses (ovals) represent mouse buttons.

      if ( left_mouse_button_is_down  ==  true )
      {
         graphics.fillOval( current_mouse_position_x - 55,
                            current_mouse_position_y + 5,
                            30, 60 ) ;
      }


      if ( middle_mouse_button_is_down  ==  true )
      {
         graphics.fillOval( current_mouse_position_x - 15,
                            current_mouse_position_y - 5,
                            30, 60 ) ;
      }


      if ( right_mouse_button_is_down  ==  true )
      {
         graphics.fillOval( current_mouse_position_x + 25,
                            current_mouse_position_y + 5,
                            30, 60 ) ;
      }
   }
}

public class MouseDemoApplet extends JApplet
{
   public void init()
   {
      getContentPane().add( new MouseDemoPanel() ) ; 
   }
}