//  PacmanMIDlet.java  (c) Kari Laitinen

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

//  2010-10-15  File created.
//  2011-04-28  Last modification.

/*  This midlet demonstrates:
       - animation
       - use of the GameCanvas class

    Notes:

       - at least in the Sun Wireless Toolkit emulator, the size of
         a GameCanvas seems to be the same as the size of a conventional
         Canvas
*/

import java.io.* ;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.Sprite ;
import javax.microedition.lcdui.game.GameCanvas ;

//  For the time being, the Pacman described by the class below
//  can only move horizontally.

class Pacman
{
   int pacman_center_point_x, pacman_center_point_y ;

   int[]  pacman_mouth_angles  =  { 90, 75, 60, 45, 30, 15,
                                    0,  15, 30, 45, 60, 75 } ;

   int  mouth_angle_index  =  0 ;

   boolean moving_left_to_right = true ;

   Pacman( int given_center_point_x,
           int given_center_point_y )
   {
      pacman_center_point_x = given_center_point_x ;
      pacman_center_point_y = given_center_point_y ;
   }

   public void turn()
   {
      moving_left_to_right  =  ! moving_left_to_right ;
   }

   public void turn_right()
   {
      moving_left_to_right  =  true ;
   }

   public void turn_left()
   {
      moving_left_to_right  =  false ;
   }

   public void move()
   {
      mouth_angle_index  ++  ;

      if ( mouth_angle_index  >=  pacman_mouth_angles.length )
      {
         mouth_angle_index  =  0  ;
      }

      if ( moving_left_to_right == true )
      {
         pacman_center_point_x += 1 ;
      }
      else
      {
         pacman_center_point_x -= 1 ;
      }

   }

   public void draw( Graphics graphics )
   {
      graphics.setColor( 0, 0, 0 ) ;

      int pacman_mouth_angle  =  pacman_mouth_angles[ mouth_angle_index ] ;

      if ( moving_left_to_right == true )
      {
         graphics.fillArc( pacman_center_point_x,
                           pacman_center_point_y,
                           100, 80,
                           pacman_mouth_angle / 2,
                           360 - pacman_mouth_angle ) ;
      }
      else
      {
         // The Pacman mouth must open to the left.

         graphics.fillArc( pacman_center_point_x,
                           pacman_center_point_y,
                           100, 80,
                           180 + pacman_mouth_angle / 2,
                           360 - pacman_mouth_angle ) ;
      }
   }
}


class PacmanCanvas extends GameCanvas
                       implements Runnable
{
   Thread   animation_thread ;
   boolean  thread_must_be_run  =  false ;

   int  canvas_width   =  getWidth() ; 
   int  canvas_height  =  getHeight() ;


   Pacman moving_pacman = new Pacman( 100, 100 ) ;

   Graphics graphics ;

   public PacmanCanvas()
   {
      super( false ) ;

      graphics = getGraphics() ;

      System.out.print( "\n " + canvas_width + " x " + canvas_height + "\n" ) ;

   }


   public synchronized void start_animation_thread()
   {
      if ( animation_thread  ==  null )
      {
         animation_thread  =  new  Thread( this ) ;
         thread_must_be_run  =  true ;
         animation_thread.start() ;
      }
   }

   public void stop_animation_thread()
   {
      if ( animation_thread  !=  null )
      {
         thread_must_be_run  =  false ;
         animation_thread.interrupt() ;
         animation_thread  =  null ;
      }
   }

   public void run()
   {
      while ( thread_must_be_run  ==  true ) 
      {
         // Check user input and turn the pacman if necessary.

         int key_state = getKeyStates() ;

         if ( ( key_state & LEFT_PRESSED ) != 0 )
         {
            moving_pacman.turn_left() ;
         }
         else if ( ( key_state & RIGHT_PRESSED) != 0 )
         {
            moving_pacman.turn_right() ;
         }
         else if ( ( key_state & UP_PRESSED ) != 0 || 
                   ( key_state & DOWN_PRESSED ) != 0 )
         {
            moving_pacman.turn() ;
         }



         //  The background color is red

         graphics.setColor( 255, 0, 0 ) ; 
         graphics.fillRect( 0, 0, canvas_width, canvas_height ) ;

         moving_pacman.move() ;

         moving_pacman.draw( graphics ) ;

         flushGraphics() ; // flushes the off-screen buffer to display.

         //  The other version of flushGraphics() would not render the
         //  entire buffer. That is probably used in applications in
         //  which processing time need to be spared.

         try
         {
            Thread.sleep( 40 ) ;
         }
         catch ( InterruptedException caught_exception )
         {
            // No actions to handle the exception.
         }
      }  
   }

}


public class PacmanMIDlet extends MIDlet
{
   Display  midlet_display  =  Display.getDisplay( this ) ;
   PacmanCanvas  pacman_canvas  =  new PacmanCanvas() ;

   protected void startApp() throws MIDletStateChangeException
   {
      midlet_display.setCurrent( pacman_canvas ) ;
      pacman_canvas.start_animation_thread() ;
   }

   protected void pauseApp()
   {
      pacman_canvas.stop_animation_thread() ;
   }

   protected void destroyApp( boolean unconditional_destruction_required )
   {
      pacman_canvas.stop_animation_thread() ;
   }
}