/*  $Id$

    Part of XPCE --- The SWI-Prolog GUI toolkit

    Author:        Jan Wielemaker and Anjo Anjewierden
    E-mail:        jan@swi.psy.uva.nl
    WWW:           http://www.swi.psy.uva.nl/projects/xpce/
    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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(emacs_annotate_mode, []).
:- use_module(library(pce)).


		 /*******************************
		 *	    THE BUFFER		*
		 *******************************/

:- pce_begin_class(emacs_annotate_buffer, emacs_buffer,
		   "Emacs Buffer with associated styles").

variable(font,		[font]  := @default, get, "Main Font").
variable(styles,	[sheet] := @default, get, "Sheet with styles").
variable(margin_width,	int := 75,	     get, "Width of annotate margin").

attach(B, Editor:editor) :->
	"Load <-font and <-styles"::
	send(B, send_super, attach, Editor),
	get(B, font, Font),
	get(B, styles, Styles),
%	get(B, margin_width, Width),		% See ->setup_mode
	(   Font \== @default
	->  send(Editor, font, Font)
	;   send(B, slot, font, Editor?font)
	),
	(   Styles \== @default
	->  send(Editor, styles, Styles)
	;   send(B, slot, styles, Editor?styles)
	),
%	send(Editor, margin_width, Width).
	true.

detach(B, Editor:editor) :->
	"Save <-font and <-styles"::
	send(B, send_super, detach, Editor),
	get(Editor, font, Font),
	get(Editor, styles, Styles),
	get(Editor, margin_width, Width),
	send(B, slot, font, Font),
	send(B, slot, styles, Styles),
	send(B, slot, margin_width, Width).


loaded(B) :->
	"Called after it has been reloaded (register style-names)"::
	get(B, styles, Styles),
	(   Styles \== @default
	->  annotate_style_name_type(Type),
	    send(Styles, for_all, message(Type?context, add, @arg1?name))
	;   true
	).


do_save(B, File:file) :->
	"Do the actual saving (as an XPCE object)"::
	send(B, save_in_file, File),
	send(B, check_point_undo),
	send(B, modified, @off).

:- pce_end_class.


		 /*******************************
		 *	   EDITING MODE		*
		 *******************************/

:- pce_autoload(style_item, library(pce_style_item)).

:- initialization
	new(KB, emacs_key_binding(emacs_annotate, emacs_text)),
	send(KB, function, '\\C-c\\C-d', define_style).

:- initialization
	new(_, syntax_table(annotate)).

:- initialization
	new(MM, emacs_mode_menu(annotate, text)),

	send(MM, append, annotate, define_style),
	send(MM, append, annotate,
	     emacs_argument_item(make_fragment, @emacs_mode?style_names)),
	send(MM, append, annotate, delete_fragment),
	send(MM, append, annotate, margin_width).


annotate_style_name_type(Type) :-
	get(@types, member, annotate_style_name, Type), !.
annotate_style_name_type(Type) :-
	new(Type, type(annotate_style_name, name_of, new(chain))).

:- initialization
	annotate_style_name_type(_).


:- pce_begin_class(emacs_annotate_mode, emacs_text_mode).

setup_mode(E) :->
	"little hack ..."::
	send(E, margin_width, E?text_buffer?margin_width).


style_names(E, Names:chain) :<-
	"Return a list of associated styles"::
	get(E?styles?members, map, @arg1?name, Names),
	send(Names, sort).

:- pce_global(@emacs_annotate_margin_recogniser,
	      make_emacs_annotate_margin_recogniser).

make_emacs_annotate_margin_recogniser(R) :-
	new(Editor, @receiver?device),
	new(Fragment, ?(@receiver, fragment, @event)),
	new(Mode, Editor?mode),

	new(S1, click_gesture(left, '', single,
			      or(message(Mode, selected_fragment,
					 Fragment),
				 message(Mode, selected_fragment, @nil)))),
	new(O1, click_gesture(left, '', double,
			      message(Mode, open_fragment, Fragment))),

	new(R, handler_group(S1, O1)).


margin_width(E, Width:int) :->
	"Set margin and attach event-handling"::
	send(E?editor, margin_width, Width),
	(   Width \== 0
	->  send(E?margin, recogniser, @emacs_annotate_margin_recogniser)
	;   true
	).


define_style(E, Name:'annotate_style_name|name') :->
	"Define a (new) fragment style"::
	(   get(E?styles, value, Name, Style)
	->  true
	;   new(Style, style)
	),
	new(D, dialog('Define Fragment Style')),
	send(D, append, new(NI, text_item(name, Name))),
	send(D, append, new(SI, style_item(style, Style))),
	send(SI, pen, 1),
	send(SI, border, 5),
	send(SI, radius, 7),
	send(D, append,
	     button(ok, message(D, return,
				create(tuple, NI?selection, SI?selection)))),
	send(D, append,
	     button(cancel, message(D, return, @nil))),
	send(D, default_button, ok),
	get(D, confirm_centered, RVal),
	send(D, destroy),
	(   RVal \== @nil
	->  get(RVal, first, StyleName),
	    get(RVal, second, StyleObject),
	    send(E, style, StyleName, StyleObject),
	    annotate_style_name_type(Type),
	    send(Type?context, add, StyleName),
	    send(E, modified, @on)
	;   fail
	).


make_fragment(E, Style:annotate_style_name) :->
	"Create a fragment from the current selection"::
	get(E, selection, point(Start, End)),
	Length is End - Start,
	get(E, text_buffer, TB),
	new(_, fragment(TB, Start, Length, Style)),
	send(E, modified, @on).


fragment(E, F:fragment) :<-
	"Find most local fragment around <-caret"::
	get(E, caret, Caret),
	get(E, find_all_fragments, message(@arg1, overlap, Caret), Frags),
	send(Frags, sort, ?(@arg1?size, compare, @arg2?size)),
	get(Frags, head, F).


delete_fragment(E) :->
	"Delete most smallest fragment around caret"::
	get(E, fragment, F),
	send(F, free),
	send(E, modified, @on).


selected_fragment(E, F:fragment*) :->
	"Make argument the current fragment"::
	send(E?editor, selected_fragment, F),
	(   F \== @nil
	->  send(E, report, status, '"%s" fragment', F?style)
	;   send(E, report, status, '')
	).


open_fragment(_E, _F:fragment) :->
	"To be implemented"::
	true.


:- pce_end_class.

