--          This file is part of SmallEiffel The GNU Eiffel Compiler.
--          Copyright (C) 1994-98 LORIA - UHP - CRIN - INRIA - FRANCE
--            Dominique COLNET and Suzanne COLLIN - colnet@loria.fr 
--                       http://www.loria.fr/SmallEiffel
-- SmallEiffel 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, or (at your option)  any  later 
-- version. SmallEiffel 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  SmallEiffel;  see the file COPYING.  If not,
-- write to the  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-- Boston, MA 02111-1307, USA.
--
class CLASS_NAME_LIST
   
inherit GLOBALS;
   
creation {EIFFEL_PARSER} make_1

creation {CLIENT_LIST} merge
   
feature {NONE}

   first: CLASS_NAME;

   remainder: FIXED_ARRAY[CLASS_NAME];
   
feature {NONE}

   make_1(cn: CLASS_NAME) is
      require
	 cn /= Void
      do
	 first := cn;
      ensure
	 count = 1;
	 item(1) = cn
      end;
   
feature {NONE}
   
   merge(l1, l2: like Current) is
      require
	 l1 /= Void;
	 l2 /= Void
      local
	 i: INTEGER;
	 cn: CLASS_NAME;
      do
	 first := l1.item(1);
	 !!remainder.with_capacity(l1.count + l2.count - 1);
	 from
	    i := l1.count;
	 until
	    i = 1
	 loop
	    remainder.add_last(l1.item(i));
	    i := i - 1;
	 end;
	 from
	    i := l2.count;
	 until
	    i = 0
	 loop
	    cn := l2.item(i);
	    if index_of(cn) = 0 then
	       remainder.add_last(cn);
	    end;
	    i := i - 1;
	 end;
      end;

feature

   count: INTEGER is
      do
	 if remainder = Void then
	    Result := 1;
	 else
	    Result := 2 + remainder.upper;
	 end;
      end;

   item(i: INTEGER): CLASS_NAME is
      require
	 i.in_range(1,count)
      do
	 if i = 1 then
	    Result := first;
	 else
	    Result := remainder.item(i - 2);
	 end;
      ensure
	 Result /= Void
      end;
   
feature {EIFFEL_PARSER}

   add_last(cn: CLASS_NAME) is
      require
	 cn /= Void
      local
	 i: INTEGER;
      do
	 i := index_of(cn);
	 if i > 0 then
	    eh.add_position(item(i).start_position);
	    warning(cn.start_position,"Same Class Name appears twice.");
	 end;
	 if remainder = Void then
	    !!remainder.with_capacity(4);
	 end;
	 remainder.add_last(cn);
      ensure
	 count = 1 + old count;
	 item(count) = cn
      end;

feature {CLIENT_LIST}

   pretty_print is
      local
	 i: INTEGER;
      do
	 from  
	    i := 1;
	 until
	    i > count
	 loop
	    item(i).pretty_print;
	    if i < count then
	       fmt.put_string(", ");
	    end;
	    i := i + 1;
	 end;
      end;
   
   gives_permission_to(cn: CLASS_NAME): BOOLEAN is
      local
	 i: INTEGER;
      do
	 if index_of(cn) > 0 then
	    Result := true;
	 else
	    from  
	       i := count;
	    until
	       Result or else i = 0
	    loop
	       Result := cn.is_subclass_of(item(i));
	       i := i - 1;	       
	    end;
	 end;
      end;

   gives_permission_to_any: BOOLEAN is
      local
	 i: INTEGER;
      do
	 from  
	    i := count;
	 until
	    Result or else i = 0
	 loop
	    Result := item(i).to_string = us_any;
	    i := i - 1;
	 end;
      end;

feature {NONE}

   index_of(n: CLASS_NAME): INTEGER is
      -- Use `to_string' for comparison.
      -- Gives 0 when `n' is not in the `list'.
      require
	 n /= Void;
      local
	 to_string: STRING;
      do
	 from  
	    to_string := n.to_string;
	    Result := count;
	 until
	    Result = 0 or else to_string = item(Result).to_string
	 loop
	    Result := Result - 1;
	 end;
      ensure
	 Result.in_range(0,count);
	 Result > 0 implies n.to_string = item(Result).to_string
      end;
   
invariant
   
   first /= Void;

   remainder /= Void implies count = 1 + remainder.count;
   
end -- CLASS_NAME_LIST