/*  $Id$

    Part of CHR (Constraint Handling Rules)

    Author:        Tom Schrijvers
    E-mail:        Tom.Schrijvers@cs.kuleuven.be
    WWW:           http://www.swi-prolog.org
    Copyright (C): 2005, K.U. Leuven

    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 Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

    As a special exception, if you link this library with other files,
    compiled with a Free Software compiler, to produce an executable, this
    library does not by itself cause the resulting executable to be covered
    by the GNU General Public License. This exception does not however
    invalidate any other reasons why the executable file might be covered by
    the GNU General Public License.
*/
:- module(chr_compiler_errors,
		[
			chr_info/3,
			chr_warning/3,
			chr_error/3,
			print_chr_error/1
		]).

:- use_module(chr_compiler_options).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% chr_info(+Type,+FormattedMessage,+MessageParameters)

chr_info(_,Message,Params) :-
	( \+verbosity_on ->
		true
	;
		long_line_with_equality_signs,
		format(user_error,'CHR compiler:\n',[]),
		format(user_error,Message,Params),
		long_line_with_equality_signs
	).


%% SWI begin
verbosity_on :-
	current_prolog_flag(verbose,V), V \== silent,
	current_prolog_flag(verbose_load,true).
%% SWI end

%% SICStus begin
%% verbosity_on.  % at the moment
%% SICStus end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% chr_warning(+Type,+FormattedMessage,+MessageParameters)

chr_warning(deprecated(Term),Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler WARNING: deprecated syntax      ~w.\n',[Term]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
        format(user_error,'    Support for deprecated syntax will be discontinued in the near future!\n',[]),
	long_line_with_equality_signs.

chr_warning(internal,Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler WARNING: something unexpected happened in the CHR compiler.\n',[]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
        format(user_error,'    Your program may not have been compiled correctly!\n',[]),
        format(user_error,'    Please contact tom.schrijvers@cs.kuleuven.be.\n',[]),
	long_line_with_equality_signs.

chr_warning(unsupported_pragma(Pragma,Rule),Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler WARNING: unsupported pragma ~w in ~@.\n',[Pragma,format_rule(Rule)]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
        format(user_error,'    Pragma is ignored!\n',[]),
	long_line_with_equality_signs.
chr_warning(problem_pragma(Pragma,Rule),Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler WARNING: unsupported pragma ~w in ~@.\n',[Pragma,format_rule(Rule)]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
	long_line_with_equality_signs.

chr_warning(_,Message,Params) :-
	( chr_pp_flag(verbosity,on) ->
		long_line_with_equality_signs,
		format(user_error,'CHR compiler WARNING:\n',[]),
		format(user_error,'    `--> ',[]),
		format(user_error,Message,Params),
		long_line_with_equality_signs
	;
		true
	).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% chr_error(+Type,+FormattedMessage,+MessageParameters)

chr_error(Type,Message,Params) :-
	throw(chr_error(error(Type,Message,Params))).

print_chr_error(error(Type,Message,Params)) :-
	print_chr_error(Type,Message,Params).

print_chr_error(syntax(Term),Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler ERROR: invalid syntax "~w".\n',[Term]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
	long_line_with_equality_signs.

print_chr_error(type_error,Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler TYPE ERROR:\n',[]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
	long_line_with_equality_signs.

print_chr_error(internal,Message,Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler ERROR: something unexpected happened in the CHR compiler.\n',[]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
        format(user_error,'    Please contact tom.schrijvers@cs.kuleuven.be.\n',[]),
	long_line_with_equality_signs.

print_chr_error(cyclic_alias(Alias),_Message,_Params) :- !,
	long_line_with_equality_signs,
	format(user_error,'CHR compiler ERROR: cyclic alias "~w".\n',[Alias]),
	format(user_error,'    `--> Aborting compilation.\n',[]),
	long_line_with_equality_signs.

print_chr_error(_,Message,Params) :-
	long_line_with_equality_signs,
	format(user_error,'CHR compiler ERROR:\n',[]),
	format(user_error,'    `--> ',[]),
	format(user_error,Message,Params),
	long_line_with_equality_signs.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


:- public
	format_rule/1.			% called using format/3 `@'

format_rule(PragmaRule) :-
	PragmaRule = pragma(_,_,Pragmas,MaybeName,N),
	( MaybeName = yes(Name) ->
		write('rule '), write(Name)
	;
		write('rule number '), write(N)
	),
	( memberchk(line_number(LineNumber),Pragmas) ->
		write(' (line '),
		write(LineNumber),
		write(')')
	;
		true
	).

long_line_with_equality_signs :-
	format(user_error,'================================================================================\n',[]).