--     The Ada Structured Library - A set of container classes and general
--     tools for use with Ada95.
--     Copyright (C) 1998  Corey Minyard (minyard@acm.org)
--
--     This library is free software; you can redistribute it and/or
--     modify it under the terms of the GNU Library General Public
--     License as published by the Free Software Foundation; either
--     version 2 of the License, or (at your option) any later version.
--
--     This library 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
--     Library General Public License for more details.
--
--     You should have received a copy of the GNU Library General Public
--     License along with this library; if not, write to the Free
--     Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
--     MA 02111-1307, USA
--

with System.Storage_Pools;

generic
   type Pool_Type is new System.Storage_Pools.Root_Storage_Pool with private;
   My_Pool : in out Pool_Type;
package Asgc.Ordered.Sortable.Dlist.Fixed_Managed is

   ------------------------------------------------------------------------
   -- This is the doubly linked list container.
   subtype Parent_Object is Ordered.Sortable.Object;
   type Object (Size : Positive) is new Parent_Object with private;
   type Object_Class is access all Object'Class;
   type Object_Ptr is access all Object;
   for Object_Ptr'Storage_Pool use My_Pool;
   for Object_Class'Storage_Pool use My_Pool;


   procedure Initialize (O : in out Object);

   procedure Adjust (O : in out Object);

   procedure Finalize (O : in out Object);

   ------------------------------------------------------------------------
   -- Abstract functions from other places that we are implementing.  See
   -- the definitions in the parent packages for descriptions of these.

   function "=" (O1, O2 : in Object) return Boolean;

   procedure Verify_Integrity (O : in Object);

   function Copy (O : in Object) return Asgc.Object_Class;

   function Member_Count (O : in Object) return Natural;

   procedure Delete (O   : in out Object;
                     Val : in Contained_Type);

   function Value_Exists (O   : in Object;
                          Val : in Contained_Type)
                          return Boolean;

   procedure Add_At (O   : in out Object;
                     Loc : in Positive;
                     Val : in Contained_Type);

   procedure Set_At (O   : in out Object;
                     Loc : in Positive;
                     Val : in Contained_Type);

   function Get_At (O   : in Object;
                    Loc : in Positive)
                    return Contained_Type;

   procedure Swap_At (O          : in out Object;
                      Loc1, Loc2 : in Positive);

   procedure Delete_At (O   : in out Object;
                        Loc : in Positive);

   procedure Push (O   : in out Object;
                   Val : in Contained_Type);

   procedure Pop (O   : in out Object;
                  Val : out Contained_Type);

   procedure Enqueue (O   : in out Object;
                      Val : in Contained_Type);

   procedure Dequeue (O   : in out Object;
                      Val : out Contained_Type);


   ------------------------------------------------------------------------
   -- An iterator for an ordered doubly linked list container.
   subtype Parent_Iterator is Ordered.Sortable.Iterator;
   type Iterator is new Parent_Iterator with private;
   type Iterator_Class is access all Iterator'Class;
   type Iterator_Ptr is access all Iterator;
   for Iterator_Ptr'Storage_Pool use My_Pool;
   for Iterator_Class'Storage_Pool use My_Pool;


   procedure Finalize (Iter : in out Iterator);

   ------------------------------------------------------------------------
   -- Abstract functions from other places that we are implementing.  See
   -- the definitions in the parent packages for descriptions of these.

   function New_Iterator (O : access Object) return Asgc.Iterator_Class;

   function New_Iterator (O : in Object_Class) return Iterator;

   procedure Set_Container (Iter : in out Iterator;
                            O    : in Asgc.Object_Class);

   procedure Free (Iter : access Iterator);

   procedure First (Iter : in out Iterator; Is_End : out End_Marker);

   procedure Next (Iter : in out Iterator; Is_End : out End_Marker);

   procedure Delete (Iter : in out Iterator; Is_End : out End_Marker);

   function Is_Same (Iter1, Iter2 : in Iterator) return Boolean;

   function Get (Iter : in Iterator) return Contained_Type;

   procedure Get_Incr (Iter   : in out Iterator;
                       Val    : out Contained_Type;
                       Is_End : out End_Marker);

   function "=" (Iter1, Iter2 : in Iterator) return Boolean;

   function "=" (Iter : in Iterator; Val : in Contained_Type) return Boolean;
   function "=" (Val : in Contained_Type; Iter : in Iterator) return Boolean;

   procedure Last (Iter : in out Iterator; Is_End : out End_Marker);
   procedure Prev (Iter : in out Iterator; Is_End : out End_Marker);

   procedure Set_Loc (Iter : out Iterator; Loc : in Positive);
   function Get_Loc (Iter : in Iterator) return Natural;

   function Is_After (Iter1, Iter2 : in Iterator) return Boolean;
   function Is_Before (Iter1, Iter2 : in Iterator) return Boolean;

   function "-" (Iter1, Iter2 : in Iterator) return Integer;
   function "+" (Iter : in Iterator; Offset : in Integer)
                 return Iterator;
   function "-" (Iter : in Iterator; Offset : in Integer)
                 return Iterator;

   procedure Swap (Iter1, Iter2 : in out Iterator);

   procedure Add_After (Iter : in out Iterator; Val : in Contained_Type);
   procedure Add_Before (Iter : in out Iterator; Val : in Contained_Type);

   procedure Set (Iter : in Iterator; Val : in Contained_Type);

   procedure Get_Decr (Iter   : in out Iterator;
                       Val    : out Contained_Type;
                       Is_End : out End_Marker);

   function ">" (Iter1, Iter2 : in Iterator) return Boolean;
   function ">" (Iter : in Iterator; Val : in Contained_Type) return Boolean;
   function ">" (Val : in Contained_Type; Iter : in Iterator) return Boolean;
   function "<" (Iter1, Iter2 : in Iterator) return Boolean;
   function "<" (Iter : in Iterator; Val : in Contained_Type) return Boolean;
   function "<" (Val : in Contained_Type; Iter : in Iterator) return Boolean;
   function ">=" (Iter1, Iter2 : in Iterator) return Boolean;
   function ">=" (Iter : in Iterator; Val : in Contained_Type) return Boolean;
   function ">=" (Val : in Contained_Type; Iter : in Iterator) return Boolean;
   function "<=" (Iter1, Iter2 : in Iterator) return Boolean;
   function "<=" (Iter : in Iterator; Val : in Contained_Type) return Boolean;
   function "<=" (Val : in Contained_Type; Iter : in Iterator) return Boolean;

   Internal_List_Error : exception;

private

   -- A doubly linked-list, a pretty straighforward data structure.


   subtype Node_Ref is Integer;
   Null_Node : constant Node_Ref := 0;

   type Node is record
      Next, Prev : Node_Ref       := Null_Node;
      Val        : Contained_Type;
   end record;

   type Node_Array is array (Node_Ref range <>) of Node;

   type Object (Size : Positive) is new Parent_Object with record
      Data       : Node_Array (1 .. Size);
      Head, Tail : Node_Ref               := Null_Node;
      Count      : Natural                := 0;
      Free_List  : Node_Ref               := Null_Node;
   end record;


   type Iterator is new Parent_Iterator with record
      Robj    : Object_Class := null;
      Pos     : Node_Ref      := Null_Node;
      Offset  : Natural      := 0;
   end record;

end Asgc.Ordered.Sortable.Dlist.Fixed_Managed;