------------------------------------------------------------------------------
------------------------------------------------------------------------------
-- Cheddar is a GNU GPL real-time scheduling analysis tool.
-- This program provides services to automatically check schedulability and
-- other performance criteria of real-time architecture models.
--
-- Copyright (C) 2002-2023, Frank Singhoff, Alain Plantec, Jerome Legrand,
--                          Hai Nam Tran, Stephane Rubini
--
-- The Cheddar project was started in 2002 by
-- Frank Singhoff, Lab-STICC UMR CNRS 6285, Universite de Bretagne Occidentale
--
-- Cheddar has been published in the "Agence de Protection des Programmes/France" in 2008.
-- Since 2008, Ellidiss technologies also contributes to the development of
-- Cheddar and provides industrial support.
--
-- The full list of contributors and sponsors can be found in README.md
--
-- This program is free software; you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation; either version 2 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program; if not, write to the Free Software
-- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
--
--
-- Contact : cheddar@listes.univ-brest.fr
--
------------------------------------------------------------------------------
-- Last update :
--    $Rev: 4589 $
--    $Date: 2023-09-29 16:02:19 +0200 (ven. 29 sept. 2023) $
--    $Author: singhoff $
------------------------------------------------------------------------------
------------------------------------------------------------------------------

with Ada.Containers.Doubly_Linked_Lists;

with task_set;              use task_set;
with scheduler;             use scheduler;
with Ada.Text_IO;           use Ada.Text_IO;
with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;

---------------------------------------------------------------------
-- Package Heuristics
-- Purpose: Contains the components that allows the modelisation
-- of the heuristics used to jump in time.
---------------------------------------------------------------------
package Heuristics is
   Optimization_Mode_Activated : Boolean := False;

---------------------- HEURISTIC TYPE DEFINITION -------------------------------
   type heuristic is interface;

   -- Abstract functions and procedures:
   function Can_Run
     (This : in out heuristic;
      Si   : in     scheduling_information) return Boolean is abstract;
   function Calculate
     (This : in out heuristic;
      Si   : in     scheduling_information) return Natural is abstract;

   -- Abstract type of an Heuristic:
   type concrete_heuristics is abstract new Heuristics.heuristic with record
      Name : Unbounded_String;
      -- *
   end record;

   type heuristic_ptr is access concrete_heuristics'class;

---------------------- TYPES OF HEURISTICS -------------------------------------
   type core_no_task_info is array (0 .. 255) of Natural;
   type heuristic_1 is new concrete_heuristics with record
      CNTI                       : core_no_task_info := (others => 0);
      Number_Of_Valid_Idle_Times : Natural           := 0;
      Current_Time               : Natural           := 0;
   end record;

   type heuristic_2 is new concrete_heuristics with record
      Commit_Unit           : Natural     := 0;
      Current_Time          : Natural     := 0;
      Remaining_Task_Id     : tasks_range := 0;
      Number_Of_Tasks_Ended : Natural     := 0;
   end record;

---------------------- METHODS -------------------------------------------------
   -- Heuristics functions and procedures:
   function Can_Run
     (This : in out heuristic_1;
      Si   : in     scheduling_information) return Boolean;
   function Can_Run
     (This : in out heuristic_2;
      Si   : in     scheduling_information) return Boolean;

   function Calculate
     (This : in out heuristic_1;
      Si   : in     scheduling_information) return Natural;
   function Calculate
     (This : in out heuristic_2;
      Si   : in     scheduling_information) return Natural;

   -- Proper to Heuristic_1::Idle_Heuristic:
   procedure Update_Values
     (This    : in out heuristic_1;
      No_Task : in     Boolean;
      Core_Id : in     Natural);
   procedure Reset_Values (This : in out heuristic_1; Core_Id : in Natural);
   --
   procedure Decrease_Idle_Times
     (This    : in out heuristic_1;
      Core_Id : in     Natural);
   procedure Increase_Idle_Times
     (This    : in out heuristic_1;
      Core_Id : in     Natural);

   -- Proper to Heuristic_2::Last_Job_Remaining_Heuristic:
   function Verify_Pre_Conditions
     (This : in out heuristic_2;
      Si   : in     scheduling_information) return Boolean;
   procedure Reset_Values
     (This : in out heuristic_2;
      Si   : in     scheduling_information);
   --
   function Get_Remaining_Task
     (This         : in out heuristic_2;
      Si           : in     scheduling_information;
      Current_Time : in     Natural) return Boolean;
   function Get_Nearest_Wake_Up_Time
     (This : in out heuristic_2;
      Si   : in     scheduling_information) return Natural;

---------------------- HEURISTICS LIST -----------------------------------------
   -- Heuristic list:
   package Heuristic_Lists is new Ada.Containers.Doubly_Linked_Lists
     (heuristic_ptr);
   use Heuristic_Lists;
   Heuristic_List : list;

---------------------- INTERFACE METHODS ---------------------------------------
   -- procedure TestCalculation(Heuristic : Concrete_Heuristics'Class);

   -- Interface methods:
   function Can_Run_Heuristic
     (Heuristic : in out concrete_heuristics'class;
      Si        : in     scheduling_information) return Boolean;

   function Calculate_Heuristic
     (Heuristic : in out concrete_heuristics'class;
      Si        : in     scheduling_information) return Natural;

---------------------- HEURISTICS DECLARATIONS ---------------------------------
   -- Heuristics declarations:
   Idle_Heuristic     : heuristic_ptr := new heuristic_1;
   Last_Job_Heuristic : heuristic_ptr := new heuristic_2;
end Heuristics;