------------------------------------------------------------------------------
--                                                                          --
--                        XVIEW ADA LIBRARY COMPONENTS                      --
--                                                                          --
--                          XV_SERVER_IMAGE_PACKAGE                         --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--          Copyright (c) 1995 Andreas Almroth, All Rights Reserved         --
--                                                                          --
-- The  XVIEW ADA  library is free software; you can redistribute it and/or --
-- modify  it  under terms of the  GNU  Library General  Public  License as --
-- published by the Free Software Foundation; either version 2, or (at your --
-- option) any later version. The XVIEW ADA 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 the XVIEW ADA library; see the file  COPYING.LIB.  If --
-- not, write to the Free  Software  Foundation, 675  Mass  Ave, Cambridge, --
-- MA 02139, USA.                                                           --
--                                                                          --
------------------------------------------------------------------------------

-- Lots of bindings to XView C functions needs the Interfaces.C package.

with Interfaces.C;

package body Xv_Server_Image_Package is

  SERVER_IMAGE_BITS : constant := 1157761537;
  XV_WIDTH          : constant := 1246234689;
  XV_HEIGHT         : constant := 1246300289;
  XV_DEPTH          : constant := 1249773569;

-----------------------------------------------------------------------------

  function Get_Server_Image (V : in Xv_Server_Image) return Server_image is
  begin
    return V.base;
  end Get_Server_Image;

-----------------------------------------------------------------------------

  procedure Finalize (V : in out Xv_Server_Image) is
    procedure Xv_Destroy (Object : Xv_Opaque);
      pragma Import (C,Xv_Destroy,"xv_destroy");
  begin
    Xv_Destroy(Xv_Opaque(V.Base));
  end Finalize;

-----------------------------------------------------------------------------

  procedure Initialize (V : in out Xv_Server_Image) is
   type M_Image_Data is array (Integer range 1..512) of Interfaces.C.Unsigned_Char;
   type M_Image_Data_Ptr is access all M_Image_Data;

     function Xv_Create (Owner : Xv_Opaque; Pkg    : Xv_Pkg_Ptr;
			 Cmd1  : Integer;   Width  : Integer;
			 Cmd2  : Integer;   Height : Integer;
                         Cmd3  : Integer;   Depth  : Integer;
                         Cmd4  : Integer;   Data   : M_Image_data;
                         Term  : Integer) return Server_Image;
     pragma Import (C,Xv_Create,"xv_create");

     type Short_Integer is range 0..65535;

     -- Convert_Value converts the given value to the systems own 
     -- presentation of values. By doing this you can use the same
     -- bitmap values on both BIG_ENDIAN and LITTLE_ENDIAN systems.

     function Convert_Value (Data : Integer) return Integer is
	function N_To_Hs (Data : Integer) return Integer;
	pragma Import (C,N_To_Hs,"ntohs");
     begin
	return N_To_Hs(Data);
     end Convert_Value;

     function Compose_Value (Data1, Data2 : Short_Integer) return Integer is
     begin
	return Integer((Data1 * 256 + Data2));
     end Compose_Value;

     procedure Split_Value (Data : Integer;
			    Dataout1, Dataout2 : in out Short_Integer) is
	type S_Integer is range 1..255;
     begin
	Dataout1 := Short_Integer(Data) / 256;
	Dataout2 := Short_Integer(Data) mod 256;
     end Split_Value;

    Xv_Server_Image_Pkg : Xv_Pkg_Ptr;
    pragma Import (C,Xv_Server_Image_Pkg,"my_xv_server_image_pkg");

    Internal_Image : aliased M_Image_Data;
    Image_Ptr : M_Image_Data_Ptr;
    I : Integer := V.The_Image'First;
    Data1, Data2 : Short_Integer;
    Data3, Data4 : Short_Integer;
  begin
     while I < V.The_Image'Last loop
        Data1 := Short_Integer(V.The_Image(I));
	Data2 := Short_Integer(V.The_Image(I + 1));
	Split_Value(Convert_Value(Compose_Value(Data1,Data2)),Data3,Data4);
	Internal_Image(I)     := Interfaces.C.Unsigned_Char(Data3);
	Internal_Image(I + 1) := Interfaces.C.Unsigned_Char(Data4);
        I := I + 2;
     end loop;

    Image_Ptr := Internal_Image'Access;
    V.base := Xv_Create(0,Xv_Server_Image_Pkg,XV_WIDTH,V.Width,
			XV_HEIGHT,V.Height,XV_DEPTH,1,
			SERVER_IMAGE_BITS,Image_ptr.all,0);

    if V.base = 0 then 
      raise NO_OBJECT_CREATED;
    end if;
  end Initialize;
end Xv_Server_Image_Package;