-- Chapter 24 - Programming exercise 1
with Text_IO; use Text_IO;
with Calendar; use Calendar;

procedure CH24_1 is

   package Int_IO is new Text_IO.Integer_IO(INTEGER);
   use Int_IO;
   package Fix_IO is new Text_IO.Fixed_IO(DAY_DURATION);
   use Fix_IO;

   Year,Month,Day : INTEGER;
   Start,Seconds  : DAY_DURATION;
   Time_And_Date  : TIME;

-- This procedure outputs the time in an Hour:Minute:Second format
--   using a FLOAT type for splitting the time into the various
--   fields.  It works fine for simple time logging but lacks the
--   accuracy required for finer time.  If finer time is required,
--   it will be necessary to keep the time in the fixed point format,
--   and use lots of type conversions to get the three fields, and
--   the fractional second field if needed.  An alternative method
--   would be to use a floating point type with more significant
--   digits to maintain the accuracy, but it would require more time
--   to execute.  This is definitely an application for the fixed
--   point data type.
   procedure Output_Time(Time_In_Seconds : DAY_DURATION) is
   Time : FLOAT;
   Hours, Minutes, Seconds : INTEGER;
   begin
      Time := FLOAT(Time_In_Seconds);
      Hours := INTEGER((Time - 30.0 * 60.0) / (60.0 * 60.0));
      Time := Time - FLOAT(Hours) * 60.0 * 60.0;
      Minutes := INTEGER((Time - 30.0) / 60.0);
      Seconds := INTEGER(Time - 0.5) mod 60;
      Put(Hours,3);
      Put(":");
      Put(Minutes,2);
      Put(":");
      Put(Seconds,2);
   end Output_Time;

begin

   Time_And_Date := Clock;
   Split(Time_And_Date,Year,Month,Day,Seconds);
   Output_Time(Seconds);
   Put_Line(" Begin 3.14 second delay");

   delay 3.14;

   Time_And_Date := Clock;
   Split(Time_And_Date,Year,Month,Day,Seconds);
   Output_Time(Seconds);
   Put_Line(" End of 3.14 second delay");

   Time_And_Date := Clock;
   Split(Time_And_Date,Year,Month,Day,Start);  -- get starting time

   for Index in 1..9 loop
      Put("The date and time are now");
      Time_And_Date := Clock;
      Split(Time_And_Date,Year,Month,Day,Seconds);
      Put(Month,3);
      delay 0.2;
      Put(Day,3);
      delay 0.1;
      Put(Year,5);
      delay 0.1;
      Put(Seconds - Start,8,3,0);
      New_Line;
      delay 0.6;
   end loop;

   Put_Line("Begin non-accumulative timing loop here.");

   Time_And_Date := Clock;
   Split(Time_And_Date,Year,Month,Day,Start);  -- get starting time
   for Index in 1..9 loop
      Time_And_Date := Clock;
      Split(Time_And_Date,Year,Month,Day,Seconds);
      Put("The elapsed time is");
      Put(Seconds - Start,8,3,0);
      New_Line;
      delay Day_Duration(Index) - (Seconds - Start);
   end loop;

   Put(" The current time is ");
   Time_And_Date := Clock;
   Split(Time_And_Date,Year,Month,Day,Seconds);
   Output_Time(Seconds);
end CH24_1;

-- Result of Execution

--  9:54:13 Begin 3.14 second delay
--  9:54:16 End of 3.14 second delay
-- The date and time are now  7 22 1988        0.000
-- The date and time are now  7 22 1988        1.090
-- The date and time are now  7 22 1988        2.140
-- The date and time are now  7 22 1988        3.180
-- The date and time are now  7 22 1988        4.230
-- The date and time are now  7 22 1988        5.270
-- The date and time are now  7 22 1988        6.320
-- The date and time are now  7 22 1988        7.360
-- The date and time are now  7 22 1988        8.400
-- Begin non-accumulative timing loop here
-- The elapsed time is       0.000
-- The elapsed time is       1.100
-- The elapsed time is       2.030
-- The elapsed time is       3.020
-- The elapsed time is       4.040
-- The elapsed time is       5.030
-- The elapsed time is       6.020
-- The elapsed time is       7.010
-- The elapsed time is       8.000
-- The current time is  9:54:35