/*  $Id$

    Part of SWI-Prolog

    Author:        Jan Wielemaker
    E-mail:        jan@swi.psy.uva.nl
    WWW:           http://www.swi-prolog.org
    Copyright (C): 1985-2002, University of Amsterdam

    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(progman,
	  [ progman_groups/1,		% -ListOfExistingGroups
	    progman_group_info/3,	% +Group, -File, -Items

	    progman_make_group/1,	% +Group
	    progman_make_group/2,	% +Group, +GroupFile
	    progman_make_item/4,	% +Group, +Title, +CmdLine, +Cwd
	    progman_make_item/5,	% +Group, +Title, +CmdLine, +Cwd, +Icon

	    progman_setup/0		% Installs icons
	  ]).

:- (   current_prolog_flag(dde, true)
   ->  true
   ;   print_message(error, missing_feature('DDE'))
   ).

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
MS-Windows  PROGMAN  interface  and  installation   for  SWI-Prolog  and
XPCE/SWI-Prolog.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

%%	progman_groups(-Groups)
%
%	Return list of atoms containing the titles of the currently
%	available program groups.

progman_groups(Groups) :-
	open_dde_conversation(progman, progman, DDE),
	dde_request(DDE, groups, Lines),
	close_dde_conversation(DDE),
	check_error(Lines),
	lines_to_atoms(Lines, Groups0),
	Groups = Groups0.

%%	progman_group_info(+Group, -File, -Items)
%
%	Extracts info on the given group: Filename used to store the
%	group and a list of item(Title, CmdLine, Dir) terms.

progman_group_info(Group, File, Items) :-
	open_dde_conversation(progman, progman, DDE),
	dde_request(DDE, Group, Info),
	close_dde_conversation(DDE),
	check_error(Info),
	lines_to_atoms(Info, [GrounInfo|ItemLines]),
	line_to_args(GrounInfo, [_,File|_]),
	maplist(map_item_info, ItemLines, Items).

%%	progman_make_group(+Name) is det.
%%	progman_make_group(+Name, +File) is det.
%
%	Create a group in the program manager.  If file is given, this
%	is the file used by Windows to store the group info.

progman_make_group(Name) :-
	open_dde_conversation(progman, progman, DDE),
	dde_fmt_execute(DDE, '[CreateGroup("~w")]', [Name]),
	close_dde_conversation(DDE).
progman_make_group(Name, File) :-
	open_dde_conversation(progman, progman, DDE),
	dde_fmt_execute(DDE, '[CreateGroup("~w", "~w")]', [Name, File]),
	close_dde_conversation(DDE).

%%	progman_make_item(+Group, +Title, +CmdLine, +Dir)
%
%	Make a new program item in the named group.  If the item already
%	exists, delete it.

progman_make_item(Group, Title, CmdLine, Dir) :-
	progman_make_item(Group, Title, CmdLine, Dir, -).
progman_make_item(Group, Title, CmdLine, Dir, Icon) :-
	(   nonvar(Icon),
	    Icon = IconFile:IconNum
	->  true
	;   Icon = IconFile
	->  IconNum = ''
	;   IconFile = '',
	    IconNum = ''
	),
	progman_group_info(Group, _File, Items),
	open_dde_conversation(progman, progman, DDE),
	dde_fmt_execute(DDE, '[ShowGroup("~w", 1)]', Group),
	(   memberchk(item(Title, _, _), Items)
	->  dde_fmt_execute(DDE, '[ReplaceItem("~w")]', [Title])
	;   true
	),
	dde_fmt_execute(DDE, '[addItem(~w,~w,~w,~w,,,~w,,)]',
			[CmdLine, Title, IconFile, IconNum, Dir]),
	close_dde_conversation(DDE).

%%	program_group(+Default, -Group)
%
%	Given a default group name, ask for a new name if this group
%	already exists.

program_group(Default, Group) :-
	progman_groups(Existing),
	memberchk(Default, Existing), !,
	(   '$confirm'(progman_replace(Default))
	->  Group = Default
	;   format('Enter new group name: '),
	    read_line(NewDef),
	    program_group(NewDef, Group)
	).
program_group(Default, Default).

		 /*******************************
		 *     ERRORS AND WARNINGS	*
		 *******************************/

%%	check_error(+Return)
%
%	Map return-codes into exeptions.

check_error(error(Error)) :-
	throw(error(dde_error, Error)).
check_error(_).


:- multifile
	prolog:message/3.

prolog:message(progman_replace(Default)) -->
	[ 'Put (replace) items in existing group ~w? '-[Default], flush ].
prolog:message(error(dde_error, Msg)) -->
	[ 'DDE error: ~w'-[Msg] ].

		 /*******************************
		 *	       INSTALL		*
		 *******************************/

progman_setup :-
	explain(start),

	program_group('SWI-Prolog', Group),
	current_prolog_flag(executable, PlExe),
	prolog_to_os_filename(PlExe, OsPlExe),

	progman_make_group(Group),
	progman_make_item(Group, 'SWI-Prolog', OsPlExe, 'c:'),
	explain(end).


		 /*******************************
		 *	      EXPLAIN		*
		 *******************************/

explanation(start, '').
explanation(start, '*******************************************************').
explanation(start, 'SWI-Prolog installation run').
explanation(start, '*******************************************************').
explanation(start, '').

explanation(end, '').
explanation(end, 'Program manager setup completed').
explanation(end, '').

explain(Id) :-
	explanation(Id, X),
	format('~w~n', [X]),
	fail ; true.

%%	line_to_args(+Line, -Args)
%
%	Translate a line (Atom) as returned by PROGMAN's request for
%	the contents of a group into a list of atomic arguments.  Arguments
%	are separated by `,', may be double-quoted and don't contain
%	blank space.

line_to_args(Line, Args) :-
	name(Line, Str),
	phrase(line(Args), Str).

map_item_info(Line, item(Title, CmdLine, Dir)) :-
	line_to_args(Line, [Title, CmdLine, Dir|_]).

line([Arg|More]) -->
	string(Arg), !,
	line(More).
line(Args) -->
	char(","), !,
	line(Args).
line([Arg|More]) -->
	char([C]),
	string_val(A0),
	(   char(",")
	;   end_of_string
	), !,
	{ name(Arg, [C|A0]) },
	line(More).
line([]) -->
	[].

string(Arg) -->
	char(""""), !,
	string_val(A0),
	char(""""), !,
	{ name(Arg, A0) }.

string_val([]) -->
	[].
string_val([C|M]) -->
	char([C]),
	string_val(M).

char([C], [C|T], T).
end_of_string([], []).

%%	lines_to_atoms(+Lines, -Atoms)
%
%	Break a multiline answer from PROGMAN in multiple atoms, each
%	describing a single line of the answer without the \r\n.

lines_to_atoms(Lines, Atoms) :-
	name(Lines, Str),
	string_to_atoms(Str, [], Atoms).

string_to_atoms([], [], []) :- !.
string_to_atoms([], S0,  [A]) :- !,
	reverse(S0, S),
	name(A, S).
string_to_atoms([13,10|Rest], S0, [A|T]) :- !,
	reverse(S0, S),
	name(A, S),
	string_to_atoms(Rest, [], T).
string_to_atoms([10|Rest], S0, [A|T]) :- !,
	reverse(S0, S),
	name(A, S),
	string_to_atoms(Rest, [], T).
string_to_atoms([C|T], M, A) :-
	string_to_atoms(T, [C|M], A).

%%	read_line(-Line)
%
%	Flush pending output and read input upto a newline.  Return the
%	entered line as an atom.

read_line(Line) :-
	flush_output,
	prompt(O, ''),
	read_chars(Chars),
	prompt(_, O),
	name(Line, Chars).

read_chars([C|T]) :-
	get0(C),
	\+ memberchk(C, [10,13,4]),
	read_chars(T).
read_chars([]).

%%	dde_fmt_execute(+DdeId, +Format, +Args)
%
%	Utility predicate to create DDE commands from a formatted spec.

dde_fmt_execute(DDE, Fmt, Args) :-
	format(string(Cmd), Fmt, Args),
	dde_execute(DDE, Cmd).