//  MovingBallOOApplet.java  (c) 2001 - 2009 Kari Laitinen

//  http://www.naturalprogramming.com

//  2005-06-07  File created.
//  2009-10-30  This is now a JPanel-based applet
//  2009-11-01  Latest modification.

//  This program is an object-oriented version of program
//  MovingBallApplet.java.

//  This one uses a class named Ball that is declared in its
//  own source program file.

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

class MovingBallOOPanel extends    JPanel
                        implements ActionListener, ItemListener
{
   JButton  left_button, up_button, down_button, right_button ;

   int  panel_width, panel_height ;

   Ball ball_on_screen  ;

   public MovingBallOOPanel( int given_width,
                             int given_height )
   {
      panel_width   =  given_width ;
      panel_height  =  given_height ;

      //  Let's create the Ball object so that the ball is in the
      //  middle of the screen at the beginning.

      ball_on_screen  =  new  Ball( panel_width / 2,
                                    panel_height / 2,
                                    Color.RED ) ;

      setLayout( new BorderLayout() ) ;

      left_button     =  new JButton( " < " ) ;
      up_button       =  new JButton( " Up " ) ;
      down_button     =  new JButton( " Down " ) ;
      right_button    =  new JButton( " > " ) ;

      left_button.addActionListener( this ) ;
      up_button.addActionListener( this ) ;
      down_button.addActionListener( this ) ;
      right_button.addActionListener( this ) ;


      JPanel operations_panel  =  new  JPanel() ;

      operations_panel.add( left_button ) ;
      operations_panel.add( up_button ) ;
      operations_panel.add( down_button ) ;
      operations_panel.add( right_button ) ;

      JComboBox  color_selection_menu  =  new JComboBox() ;

      color_selection_menu.addItem( "red" ) ;
      color_selection_menu.addItem( "orange" ) ;
      color_selection_menu.addItem( "yellow" ) ;
      color_selection_menu.addItem( "green" ) ;
      color_selection_menu.addItem( "blue" ) ;
      color_selection_menu.addItem( "magenta" ) ;
      color_selection_menu.addItem( "cyan" ) ;
      color_selection_menu.addItem( "pink" ) ;
      color_selection_menu.addItem( "lightGray" ) ;

      color_selection_menu.addItemListener( this ) ;

      operations_panel.add( color_selection_menu ) ;

      add( "South", operations_panel ) ;

   }

   public void actionPerformed( ActionEvent event )
   {
      if ( event.getSource() instanceof JButton )
      {
         if ( event.getSource()  ==  left_button )
         {
            ball_on_screen.move_left() ;
         }
         else if ( event.getSource()  ==  up_button )
         {
            ball_on_screen.move_up() ;
         }
         else if ( event.getSource()  ==  down_button )
         {
            ball_on_screen.move_down() ;
         }
         else if ( event.getSource()  ==  right_button )
         {
            ball_on_screen.move_right() ;
         }

         repaint() ;
      }
   }

   public void itemStateChanged( ItemEvent menu_selection )
   {
      String selected_color  =  (String) menu_selection.getItem() ;

      if ( selected_color.equals( "red" ) )
      {
         ball_on_screen.set_color( Color.red ) ;
      }
      else if ( selected_color.equals( "orange" ) )
      {
         ball_on_screen.set_color( Color.orange ) ;
      }
      else if ( selected_color.equals( "yellow" ) )
      {
         ball_on_screen.set_color( Color.yellow ) ;
      }
      else if ( selected_color.equals( "green" ) )
      {
         ball_on_screen.set_color( Color.green ) ;
      }
      else if ( selected_color.equals( "blue" ) )
      {
         ball_on_screen.set_color( Color.blue ) ;
      }
      else if ( selected_color.equals( "magenta" ) )
      {
         ball_on_screen.set_color( Color.magenta ) ;
      }
      else if ( selected_color.equals( "cyan" ) )
      {
         ball_on_screen.set_color( Color.cyan ) ;
      }
      else if ( selected_color.equals( "pink" ) )
      {
         ball_on_screen.set_color( Color.pink ) ;
      }
      else if ( selected_color.equals( "lightGray" ) )
      {
         ball_on_screen.set_color( Color.lightGray ) ;
      }

      repaint() ;
   }

   public void paintComponent( Graphics graphics )
   {
      //  The superclass version of paintComponent() method draws the buttons
      //  and the color selection menu to the screen.

      super.paintComponent( graphics ) ;

      ball_on_screen.draw( graphics ) ;

      graphics.setColor( Color.black ) ;

      graphics.drawString( "("   +  ball_on_screen.get_ball_center_point_x()  +
                           ", "  +  ball_on_screen.get_ball_center_point_y()  +
                           ")",  20, 20 ) ;
   }
}


public class MovingBallOOApplet extends JApplet
{
   public void init()
   {
      getContentPane().add( new MovingBallOOPanel( getSize().width,
                                                   getSize().height ) ) ; 
   } 
}