with Text_Io;
use Text_Io;
package body Gmface.Gm_Case is
   
   function Filetype (Filename : in String)
		     return Work_Enum is
      
      File : File_Type;
      
   begin
      
      Open(File, In_File, Filename);
      declare
	 Line : constant String := Get_Line(File);
      begin
	 if Line'Length >= 4 then
	    if Line(1..4) = Gmidi_Header then
	       Close(File);
	       return Gmidi_Work;
	    elsif Line(1..4) = Gmface_Header then
	       Close(File);
	       return Gmface_Work;
	    else
	       Close(File);
	       raise Program_Error;
	    end if;
	 else
	    Close(File);
	    raise Program_Error;
	 end if;
      end;
      
   end Filetype;
	             
end Gmface.Gm_Case;