-- FILE: driver.adb
-- AUTHOR: G. Levine
-- DATE: December 1996
-- PURPOSE: driver for the game of life implemented with tasks;
--          specifically, each cell is implemented as a separate task with
--          current cell condition (alive or dead) communicated 
--          between cells.  This implementation may allow extension to
--          more complex cell dynamics.
  
with LIFE_GAME,
     TEXT_IO;
with Ada.COMMAND_LINE;
procedure Driver is
     Low1      : INTEGER := 1;              -- dimensions of the grid 
     Low2      : INTEGER := 1;
     High1     : INTEGER := 15;
     High2     : INTEGER := 15; 
     Live_Mark : CHARACTER := '*';         -- output characters
     Dead_Mark : CHARACTER := ' '; 
     Argument_Number: NATURAL;
     Last      : Natural;
     package INT_IO is new TEXT_IO.INTEGER_IO (INTEGER);

   function Valid (Str: STRING) return BOOLEAN is
     Test :BOOLEAN;
   begin
         Test := (Str(1) >= '0' and then Str(1) <= '9') or else
                   Str(1) = '-' or else Str(1) = '+' ;
         if Test then
            for i in Str'First + 1 .. Str'Last loop    
               Test := (Str(i) >='0' and then str(i) <= '9');
               exit when not Test;
            end loop;
         end if;
         return Test;
   end Valid;

begin
   TEXT_IO.Put (Ada.COMMAND_LINE.Command_Name);
   Argument_Number := Ada.COMMAND_LINE.Argument_Count;
   
   if Argument_Number < 4 then 
     TEXT_IO.Put_Line ("You did not enter any arguments");
   elsif
     not Valid (Ada.Command_Line.Argument(1)) or else
     not Valid (Ada.Command_Line.Argument(2)) or else
     not Valid (Ada.Command_Line.Argument(3)) or else
     not Valid (Ada.Command_Line.Argument(4)) then
        TEXT_IO.Put_Line ("Invalid Arguments");
        TEXT_IO.Put_Line ("Enter 4 arguments, low to high for grid size");
   else
      Int_IO.Get( Ada.Command_Line.Argument (1), Low1,Last) ;
      Int_IO.Get (Ada.Command_Line.Argument (2), High1,Last);
      Int_IO.Get (Ada.Command_Line.Argument (3), Low2,Last);
      Int_IO.Get (Ada.Command_Line.Argument (4), High2,Last);
      if High1 - Low1 > 15 or else High1 - Low1 < 1 or else
         High2 - Low2 > 15 or else High2 - Low2 < 1 then
         TEXT_IO.Put_Line("Arguments must be integers low to high,low to high");
         TEXT_IO.Put_Line("Maximum grid size 15 by 15"); 
      else
        declare  
          package LIFE is new Life_Game (High1, High2,
                                      Low1, Low2,
                                      Live_Mark, Dead_Mark);
        begin               
          LIFE.Start;
        end;
      end if;
    end if; 
exception
  when others => NULL;
end Driver;