//  ClockOldApplet.java  (c) 2000-2009 Kari Laitinen

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

//  2000-??-??  File created.
//  2009-10-13  Last modification.

/*  This program prints a clock onto the screen once in every second.
    The clock thus seems to run when this program is executing.

    This program demonstrates:
      -  how to use a thread that maintains animation
      -  how to get the current time and date by "reading" the computer's clock

    See program ClockWithDate.java to find out how to to build a better
    graphical clock.

*/

import java.awt.* ;
import javax.swing.* ;
import java.util.* ;  //  Calendar and GregorianCalendar classes are here.

public class ClockOldApplet extends JApplet
                            implements Runnable
{
   Thread  thread_that_runs_the_clock ;

   boolean  thread_must_be_executed ;

   public void start()
   {
      if ( thread_that_runs_the_clock  ==  null )
      {
         thread_must_be_executed     =  true ;
         thread_that_runs_the_clock  =  new  Thread( this ) ;

         thread_that_runs_the_clock.start() ;
      }
   }

   public void stop()
   {
      if ( thread_that_runs_the_clock  !=  null )
      {
         thread_must_be_executed  =  false ;
         thread_that_runs_the_clock.interrupt() ;

         thread_that_runs_the_clock  =  null ;
      }
   }

   public void run()
   {
      while ( thread_must_be_executed  ==  true ) 
      {
         repaint() ;

         try
         {
            Thread.sleep( 1000 ) ;  // Suspend for 1 second.
         }
         catch ( InterruptedException caught_exception )
         {
            // No actions to handle the exception.
         }
      }  
   }


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

      String[]  days_of_week  =  { "Sunday", "Monday", "Tuesday",
               "Wednesday", "Thursday", "Friday", "Saturday" } ;

      String[]  names_of_months  =  

         { "January", "February", "March", "April",
           "May", "June", "July", "August",
           "September", "October", "November", "December" } ;

      Calendar time_now  = new GregorianCalendar() ;

      int current_year     =  time_now.get( Calendar.YEAR ) ;
      int current_day      =  time_now.get( Calendar.DAY_OF_MONTH ) ;
      int month_index      =  time_now.get( Calendar.MONTH ) ;
      int number_of_day_of_week
                           =  time_now.get( Calendar.DAY_OF_WEEK ) ;

      String  current_month  =  names_of_months[ month_index ] ;

      String  current_day_of_week  =
                                days_of_week[ number_of_day_of_week - 1 ] ;

      int current_hours    =  time_now.get( Calendar.HOUR_OF_DAY ) ;
      int current_minutes  =  time_now.get( Calendar.MINUTE ) ;
      int current_seconds  =  time_now.get( Calendar.SECOND ) ;

      graphics.drawString( ""   + current_day_of_week  +
                           ", "  + current_month +
                           " "  + current_day   +
                           ", " + current_year      , 20, 20 ) ;

      graphics.drawString( String.format( "%d:%02d:%02d",
                           current_hours, current_minutes, current_seconds ),
                           20, 40 ) ;


      int  clock_center_point_x  =  300 ;
      int  clock_center_point_y  =  200 ;

      int[]  minute_hand_end_points_x  =

        {  0,  11,  21,  31,  41,  50,  59,  67,  74,  81,
          87,  91,  95,  97,  99,
         100,  99,  97,  95,  91,  87,  81,  74,  67,  59,
          50,  41,  31,  21,  11,
           0, -11, -21, -31, -41, -50, -59, -67, -74, -81,
         -87, -91, -95, -97, -99,
        -100, -99, -97, -95, -91, -87, -81, -74, -67, -59,
         -50, -41, -31, -21, -11 } ;

      int[]  minute_hand_end_points_y  =

      { -100, -99, -97, -95, -91, -87, -81, -74, -67, -59,
         -50, -41, -31, -21, -11,
           0,  11,  21,  31,  41,  50,  59,  67,  74,  81,
          87,  91,  95,  97,  99,
         100,  99,  97,  95,  91,  87,  81,  74,  67,  59,
          50,  41,  31,  21,  11,
           0, -11, -21, -31, -41, -50, -59, -67, -74, -81,
         -87, -91, -95, -97, -99  } ;

      int[]  hour_hand_end_points_x  =

        {  0,   7,  13,  19,  24,  30,  35,  40,  44,  48,
          52,  55,  57,  58,  59,
          60,  59,  58,  57,  55,  52,  48,  44,  40,  35,
          30,  24,  19,  13,   7,
           0,  -7, -13, -19, -24, -30, -35, -40, -44, -48,
         -52, -55, -57, -58, -59,
         -60, -59, -58, -57, -55, -52, -48, -44, -40, -35,
         -30, -24, -19, -13,  -7  } ;

      int[]  hour_hand_end_points_y  =

       { -60, -59, -58, -57, -55, -52, -48, -44, -40, -35,
         -30, -24, -19, -13,  -7,
           0,   7,  13,  19,  24,  30,  35,  40,  44,  48,
          52,  55,  57,  58,  59,
          60,  59,  58,  57,  55,  52,  48,  44,  40,  35,
          30,  24,  19,  13,   7,
           0,  -7, -13, -19, -24, -30, -35, -40, -44, -48,
         -52, -55, -57, -58, -59  } ;

      // Let's print an 8-point dot in the center of the clock.

      graphics.fillOval( clock_center_point_x - 4,
                         clock_center_point_y - 4, 8, 8 ) ;

      // The following loop prints dots on the clock circle.

      int minute_index  =  0 ;

      while ( minute_index  <  60 )
      {
         graphics.fillOval(

            clock_center_point_x +
            minute_hand_end_points_x[ minute_index ] - 2,

            clock_center_point_y +
            minute_hand_end_points_y[ minute_index ] - 2, 4, 4 ) ;

         minute_index  =  minute_index  +  5  ;
      }


      //  A clock goes through its 12-hour scale twice every day.

      int  hour_index  ;

      if ( current_hours  >=  12 )
      {
         hour_index  =  current_hours  -  12 ;
      }
      else
      {
         hour_index  =  current_hours ;
      }

      //  Remember that we have 60 minutes in every hour,
      //  but not 60 hours in a day.

      hour_index  =  hour_index  *  5  +
                     current_minutes  /  12 ;

      //  Let's draw the hour hand of the clock.

      graphics.drawLine( clock_center_point_x,
                         clock_center_point_y,
            
                         clock_center_point_x  +
                                  hour_hand_end_points_x[ hour_index ],
                         clock_center_point_y  +
                                  hour_hand_end_points_y[ hour_index ]  ) ;

      //  The minute and second hands are longer than
      //  the hour hand. Therefore we use different
      //  coordinates to print them.

      graphics.drawLine( clock_center_point_x,
                         clock_center_point_y,

                         clock_center_point_x  +
                                  minute_hand_end_points_x[ current_minutes ],
                         clock_center_point_y  +
                                  minute_hand_end_points_y[ current_minutes ] );

      graphics.drawLine( clock_center_point_x,
                         clock_center_point_y,
            
                         clock_center_point_x  +
                                  minute_hand_end_points_x[ current_seconds ],
                         clock_center_point_y  +
                                  minute_hand_end_points_y[ current_seconds ]);

   }
}