1/*  Part of XPCE --- The SWI-Prolog GUI toolkit
   2
   3    Author:        Jan Wielemaker and Anjo Anjewierden
   4    E-mail:        wielemak@science.uva.nl
   5    WWW:           http://www.swi-prolog.org/projects/xpce/
   6    Copyright (c)  1985-2007, University of Amsterdam
   7    All rights reserved.
   8
   9    Redistribution and use in source and binary forms, with or without
  10    modification, are permitted provided that the following conditions
  11    are met:
  12
  13    1. Redistributions of source code must retain the above copyright
  14       notice, this list of conditions and the following disclaimer.
  15
  16    2. Redistributions in binary form must reproduce the above copyright
  17       notice, this list of conditions and the following disclaimer in
  18       the documentation and/or other materials provided with the
  19       distribution.
  20
  21    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  25    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  29    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  31    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32    POSSIBILITY OF SUCH DAMAGE.
  33*/
  34
  35:- module(pce_portray_object,
  36        [ portray_object/1
  37        , portray_object/2
  38        ]).
  39
  40
  41:- use_module(library(pce)).
  42:- require([ maplist/3,
  43             memberchk/2
  44           ]).
  45
  46/** <module> Create Human readable XPCE object descriptions
  47
  48Note: you may wish to  incorporate   portray_object/2  with the standard
  49portray mechanism of your Prolog. In that case:
  50
  51==
  52portray(Object) :-
  53        object(Object), !,
  54        portray_object(Object).
  55==
  56
  57Sometimes the use of  object  references  can   be  a  new  nuisance, in
  58particular while writing and debugging PCE   programs.  Suppose you have
  59done:
  60
  61==
  62    new(@s, spatial(xref=x+w, yref=x+h/2, xref=x, yref=y+h))
  63==
  64
  65then
  66
  67==
  68    object(@s, S)
  69    S = spatial(@1234, @1235, @1236, @1237, @default, @default)
  70==
  71
  72is not of much use.  portray_object/2 makes life easier:
  73
  74==
  75    portray_object(@s, S)
  76    S = spatial(xref=x+w, yref=x+h/2, xref=x, yref=y+h)
  77==
  78
  79More or less  expanding  the  arguments   until  they  become  readable.
  80portray_object/3 uses rules which  specify  how   each  object  will  be
  81portrayed. You can make private extensions to these rules if you like.
  82*/
  83
  84%!  portray_class(Description, Term)
  85%
  86%   Term is a template which  may   contain  object references which
  87%   need to be  portrayed  recursively   (indicated  with  the  "p/"
  88%   prefix):
  89%
  90%   ==
  91%   portray_class(constraint(A, B, C), _, constraint(A, B, p/C)).
  92%   ==
  93%
  94%   Which should not touch the first two   arguments  (A and B), but
  95%   portrays C recursively.
  96
  97vararg_class(Class) :-
  98    get(@pce, convert, Class, class, TheClass),
  99    get(TheClass, term_names, @nil).
 100
 101portray_class(+(A, B), +(p/A, p/B)).
 102portray_class(-(A, B), -(p/A, p/B)).
 103portray_class(*(A, B), *(p/A, p/B)).
 104portray_class(/(A, B), /(p/A, p/B)).
 105portray_class(=(A, B), =(p/A, p/B)).
 106portray_class(==(A, B), ==(p/A, p/B)).
 107portray_class(\==(A, B), \==(p/A, p/B)).
 108portray_class(if(A,B,C), if(p/A, p/B, p/C)).
 109portray_class(while(A,B), while(p/A, p/B)).
 110portray_class(when(A,B,C), when(p/A, p/B, p/C)).
 111portray_class(attribute(A, B), attribute(A, p/B)).
 112portray_class(constraint(A, B, C), constraint(A, B, p/C)).
 113portray_class(handler(A, B, C), handler(A, p/B, p/C)).
 114portray_class(identity(A, A), identity(A)).
 115portray_class(identity(A, B), identity(A, B)).
 116portray_class(line(A, B, C, D), line(A, B, C, D)).
 117portray_class(link(A, A, _), link(A)).
 118portray_class(link(A, B, C), link(A, B, p/C)).
 119portray_class(number(A), A).
 120portray_class(node(A), node(p/A)).
 121portray_class(text(A,B,C), text(p/A, B, C)).
 122portray_class(button(A,B), button(A, p/B)).
 123portray_class(real(A), A).
 124portray_class(type(Name, _, _, _), Name).
 125portray_class(spatial(A, B, C, D, @default, @default), spatial(p/A, p/B, p/C, p/D)).
 126portray_class(spatial(A, B, C, D, @nil, @nil), spatial(p/A, p/B, p/C, p/D)).
 127portray_class(spatial(A, B, C, D, E, F), spatial(p/A, p/B, p/C, p/D, p/E, p/F)).
 128portray_class(string(A), A).
 129portray_class(click_gesture(A, B, C, D, E, F),
 130              click_gesture(A, p/B, C, p/D, p/E, p/F)).
 131portray_class(handle(A,B,C,D), handle(p/A, p/B, C, D)).
 132portray_class(quote_function(X), quote_function(p/X)).
 133portray_class(Term, NewTerm) :-
 134    functor(Term, Functor, _),
 135    vararg_class(Functor),
 136    !,
 137    Term =.. [Functor|Arguments],
 138    maplist(tag_p, Arguments, NewArguments),
 139    NewTerm =.. [Functor|NewArguments].
 140portray_class(A, A).
 141
 142tag_p(X, p/X).
 143
 144%!  global_object(+Ref)
 145%
 146%   Declare commonly known objects
 147
 148global_object(@nil).
 149global_object(@default).
 150global_object(@arg1).
 151global_object(@arg2).
 152global_object(@arg3).
 153global_object(@arg4).
 154global_object(@arg5).
 155global_object(@arg6).
 156global_object(@arg7).
 157global_object(@arg8).
 158global_object(@arg9).
 159global_object(@arg10).
 160global_object(@receiver).
 161global_object(@event).
 162global_object(@pce).
 163global_object(@prolog).
 164global_object(@display).
 165global_object(@classes).
 166global_object(@cursor_names).
 167global_object(@event_tree).
 168global_object(@white_image).
 169global_object(@grey12_image).
 170global_object(@grey25_image).
 171global_object(@grey50_image).
 172global_object(@grey75_image).
 173global_object(@black_image).
 174global_object(@on).
 175global_object(@off).
 176
 177%!  portray_object(@Object)
 178%
 179%   Prints the result of portray_object/2 on the display.
 180
 181portray_object(Object) :-
 182    portray_object(Object, Term),
 183    print(Term), nl,
 184    !.
 185
 186
 187%!  portray_object(@Object, -Term)
 188%
 189%   Expands the object description of  Object   in  a human readable
 190%   form and returs this in Term.   portray_object/2  uses the rules
 191%   found under portray_class/2.
 192
 193portray_object(Obj, Term) :-
 194    portray_object(Obj, Term, []).
 195
 196portray_object(@Object, @Object, _) :-
 197    global_object(@Object),
 198    !.
 199portray_object(Obj, '<recursive>'(Obj), Done) :-
 200    memberchk(Obj, Done),
 201    !.
 202portray_object(@Object, Term, Done) :-
 203    object(@Object, Description),
 204    portray_class(Description, Result),
 205    portray_description(Result, Term, [@Object|Done]),
 206    !.
 207portray_object(Term, Term, _).
 208
 209portray_description(Result, Term, Done) :-
 210    Result =.. Arguments,
 211    maplist(portray_argument(Done), Arguments, List),
 212    !,
 213    Term =.. List.
 214portray_description(Term, Term, _).
 215
 216portray_argument(Done, p/Object, Term) :-
 217    !,
 218    portray_object(Object, Term, Done).
 219portray_argument(_, Term, Term).