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

    Author:        Jan Wielemaker and Anjo Anjewierden
    E-mail:        J.Wielemaker@vu.nl
    WWW:           http://www.swi.psy.uva.nl/projects/xpce/
    Copyright (c)  2001-2011, University of Amsterdam
                              VU University Amsterdam
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in
       the documentation and/or other materials provided with the
       distribution.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/

:- module(prolog_xbrowse,
          [ x_browse_analyse/1,         % +file
            x_browse_info/2,            % +File, +Key(-Value ...)
            x_browse_free/1,            % +File
            system_predicate/1,         % +Head
            global_predicate/1          % +Head
          ]).
:- use_module(library(pce)).
:- use_module(library(prolog_source)).

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
This file has a common origin  as library(pce_prolog_xref). I'm not sure
what to do: merge them or decide they  are different enough not to do so
and base them on a common  ground.   Right  now we import some important
things from library(pce_prolog_xref).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

target_prolog(native).                  % The prolog system itself
%target_prolog(common).                 % Common between QP 3.2 and SICStus 3

                 /*******************************
                 *             QUERY            *
                 *******************************/

x_browse_info(Id, export(Head)) :-
    x_public(Id, Head).
x_browse_info(Id, entity(Entity, Line)) :-
    x_entity(Id, Entity, Line).


                 /*******************************
                 *             STATE            *
                 *******************************/

:- dynamic
    current_id/1,
    current_class/1,
    called/2,
    defined/1,
    imported/1,
    x_module/1.

clean :-
    retractall(called(_, _)),
    retractall(defined(_)),
    retractall(imported(_)),
    retractall(current_id(_)),
    retractall(current_class(_)),
    retractall(x_module(_)).


                 /*******************************
                 *           DATABASE           *
                 *******************************/

:- dynamic
    x_public/2,                     % Id, Head
    x_entity/3.                     % Id, Entity, Line

x_browse_free(Key) :-
    retractall(x_public(Key, _)),
    retractall(x_entity(Key, _, _)).

assert_entity(Entity) :-
    current_id(Key),
    !,
    assert_entity(Key, Entity).

assert_entity(Key, Entity) :-           % already done
    x_entity(Key, Entity, _),
    !.
assert_entity(Key, Entity) :-           % with source location
    source_location(_, Line),
    !,
    assert(x_entity(Key, Entity, Line)).
assert_entity(Key, Entity) :-           % without source
    assert(x_entity(Key, Entity, -)).

assert_predicate(M:Head) :-
    !,
    functor(Head, Name, Arity),
    functor(VarHead, Name, Arity),
    (   current_class(Class)
    ->  assert_entity(xpce_class_local_predicate(Class, M:VarHead))
    ;   assert_entity(predicate(M:VarHead))
    ).
assert_predicate(Head) :-
    functor(Head, Name, Arity),
    functor(VarHead, Name, Arity),
    (   current_class(Class)
    ->  assert_entity(xpce_class_local_predicate(Class, VarHead))
    ;   assert_entity(predicate(VarHead))
    ).

                 /*******************************
                 *           BUILT-INS          *
                 *******************************/


:- use_module(library('xref/common')).          % Common built-in's

system_predicate(Head) :-
    target_prolog(native),
    !,
    predicate_property(user:Head, built_in).
system_predicate(Head) :-
    built_in(Head).

global_predicate(Head) :-
    system_predicate(Head),
    !.
global_predicate(Head) :-                       % SWI-Prolog
    target_prolog(native),
    current_predicate(_, user:Head),
    !.


                /********************************
                *            TOPLEVEL           *
                ********************************/

x_browse_analyse(File) :-
    clean,                          % play safe
    x_browse_free(File),
    setup_call_cleanup(( prolog_open_source(File, Fd),
                         asserta(current_id(File), Ref),
                         set_xref(OldXref)),
                       process_file(Fd),
                       ( set_prolog_flag(xref, OldXref),
                         erase(Ref),
                         post_analysis
                       )).

set_xref(OldXref) :-
    (   current_prolog_flag(xref, OldXref)
    ->  true
    ;   OldXref = false
    ),
    set_prolog_flag(xref, true).


process_file(In) :-
    repeat,
      catch(prolog_read_source_term(In, Term, Expanded, []),
            _,
            fail),
      ignore(process_raw(Term)),
      (   is_list(Expanded)
      ->  member(T, Expanded)
      ;   T = Expanded
      ),
    (   T == end_of_file
    ->  !
    ;   process(T),
        fail
    ).


                 /*******************************
                 *           PROCESS RAW        *
                 *******************************/

strip_method_documentation(::(Doc,Body), Doc, Body).
strip_method_documentation(Body,         '',  Body).

class_name_from_spec(_:Term, Name) :-
    !,
    functor(Term, Name, _).
class_name_from_spec(Term, Name) :-
    functor(Term, Name, _).

process_raw(end_of_file) :- !.
process_raw((:- module(Name, Public))) :-               % must be the first!
    current_id(Id),
    asserta(x_module(Name)),
    assert_entity(module(Name)),
    (   member(PName/Arity, Public),
        functor(Head, PName, Arity),
        assert(x_public(Id, Head)),
        fail
    ;   true
    ).
process_raw(:->(Head, DocAndBody)) :-
    functor(Head, Name, _),
    current_class(Class),
    strip_method_documentation(DocAndBody, Doc, Body),
    assert_entity(xpce_method(send(Class, Name, Doc))),
    process_body(Body, xpce_method(send(Class, Name))).
process_raw(:<-(Head, DocAndBody)) :-
    functor(Head, Name, _),
    current_class(Class),
    strip_method_documentation(DocAndBody, Doc, Body),
    assert_entity(xpce_method(get(Class, Name, Doc))),
    process_body(Body, xpce_method(get(Class, Name))).
process_raw(variable(Name, _, _, Doc)) :-
    current_class(Class),
    assert_entity(xpce_variable(Class, Name, Doc)).
process_raw(variable(Name, Type, Access)) :-
    process_raw(variable(Name, Type, Access, '')).
process_raw(class_variable(Name, _, _, Doc)) :-
    current_class(Class),
    assert_entity(xpce_class_variable(Class, Name, Doc)).
process_raw(class_variable(Name, Type, Default)) :-
    process_raw(class_variable(Name, Type, Default, '')).
process_raw((:- PceDirective)) :-
    xpce_map(PceDirective, Mapped),
    !,
    process_raw((:- Mapped)).
process_raw((:- pce_begin_class(Term, Super, Doc))) :-
    class_name_from_spec(Term, Class),
    asserta(current_class(Class)),
    assert_entity(xpce_class(Class, Super, Doc)).
process_raw((:- pce_extend_class(Class))) :-
    asserta(current_class(Class)),
    assert_entity(xpce_class_extension(Class)).
process_raw((:- pce_end_class(Class))) :-
    (   current_class(Current)
    ->  (   Current = Class
        ->  retract(current_class(Class))
        ;   print_message(error,
                          end_class_mismatch(Class, Current))
        )
    ;   print_message(error, no_class_to_end)
    ).
process_raw(pce_ifhostproperty(_Cond, Terms)) :-   % ???
    !,
    (   is_list(Terms)
    ->  maplist(process_raw, Terms)
    ;   process_raw(Terms)
    ).
process_raw((Head --> _Body)) :-
    functor(Head, Name, Arity),
    PredArity is Arity+2,
    functor(VarHead, Name, PredArity),
    assert_entity(grammar_rule(VarHead)).
process_raw((:- Directive)) :-
    assert_entity(directive(Directive)).
process_raw((?- Directive)) :-
    assert_entity(directive(Directive)).
process_raw((M:Head :- _Body)) :-
    assert_predicate(M:Head).
process_raw((M:Head)) :-
    assert_predicate(M:Head).
process_raw((Head :- _Body)) :-
    assert_predicate(Head).
process_raw(Head) :-
    assert_predicate(Head).

xpce_map(pce_begin_class(Class, Super),
         pce_begin_class(Class, Super, @default)).
xpce_map(pce_end_class,
         pce_end_class(_)).
xpce_map(draw_begin_shape(Class, Super, Doc, _Event),
         pce_begin_class(Class, Super, Doc)).
xpce_map(draw_end_shape,
         pce_end_class(_)).
xpce_map(emacs_begin_mode(Mode, SuperMode, Doc, _, _),
         pce_begin_class(Class, Super, Doc)) :-
    atomic_list_concat([emacs, Mode, mode], '_', Class),
    atomic_list_concat([emacs, SuperMode, mode], '_', Super).
xpce_map(emacs_extend_mode(Mode, _),
         pce_extend_class(Class)) :-
    atomic_list_concat([emacs, Mode, mode], '_', Class).
xpce_map(emacs_end_mode,
         pce_end_class(_)).


                 /*******************************
                 *           PROCESS            *
                 *******************************/

process(end_of_file) :- !.
process((:- Directive)) :-
    !,
    process_directive(Directive),
    !.
process((Head :- Body)) :-
    !,
    assert_defined(Head),
    unbind_head(Head, VarHead),
    functor(Head, Name, Arity),
    functor(VarHead, Name, Arity),
    process_body(Body, VarHead).
process('$source_location'(_File, _Line):Clause) :-
    !,
    process(Clause).
process(Head) :-
    assert_defined(Head).

unbind_head(X, _) :-
    var(X),
    !.
unbind_head(Module:Head, Module:VarHead) :-
    !,
    unbind_head(Head, VarHead).
unbind_head(Head, VarHead) :-
    !,
    functor(Head, Name, Arity),
    functor(VarHead, Name, Arity).


                /********************************
                 *           DIRECTIVES         *
                 ********************************/

process_directive(List) :-
    is_list(List),
    !,
    process_directive(consult(List)).
process_directive(use_module(_Module, Import)) :-
    assert_import(Import).
process_directive(require(Import)) :-    % Include if report only
    assert_require(Import).
process_directive(use_module(Modules)) :-
    process_use_module(Modules).
process_directive(consult(Modules)) :-
    process_use_module(Modules).
process_directive(ensure_loaded(Modules)) :-
    process_use_module(Modules).
process_directive(dynamic(Dynamic)) :-
    assert_dynamic(Dynamic).

process_directive(op(P, A, N)) :-
    op(P, A, N).                    % should be local ...
process_directive(Goal) :-
    process_body(Goal, (:- _)).


              /********************************
              *             BODY                *
              ********************************/

%       xpce_message_goal(+Goal, -Called)
%
%       Find calls due to message(@prolog, ...) terms.  We donot try to
%       find out whether it just concerns a data object, or is actually
%       an argument in the proper place from send, get or new.  This to
%       avoid missing cases like
%
%               Condition = message(@prolog, foobar, @arg1),
%               ...
%               menu_item(foo, condition := Condition).

cascade_functor(message).
cascade_functor(?).

xpce_message_goal(Goal, SubGoal) :-
    term_member(Goal, SubTerm),
    compound(SubTerm),
    functor(SubTerm, Functor, _),
    cascade_functor(Functor),
    arg(1, SubTerm, Prolog),
    Prolog == @(prolog),
    (   (   SubTerm =.. [message, _, call | Rest]
        ;   SubTerm =.. [message, _ | Rest]
        )
    ->  true
    ;   (   SubTerm =.. [?, _, call | Rest0]
        ;   SubTerm =.. [?, _ | Rest0]
        )
    ->  append(Rest0, [_Result], Rest)
    ),
    SubGoal =.. Rest.

process_body(Goal, From) :-
    xref_meta(Goal, Metas),
    !,
    assert_called(Goal, From),
    process_called_list(Metas, From).
process_body(Goal, From) :-
    xpce_message_goal(Goal, SubGoal),
    process_body(SubGoal, From),
    fail.
process_body(Goal, From) :-
    assert_called(Goal, From).

process_called_list([], _).
process_called_list([H|T], From) :-
    process_meta(H, From),
    process_called_list(T, From).

process_meta(A+N, From) :-
    !,
    callable(A),
    \+ A = _:_,                     % avoid expanding call(M:P, ...)
    A =.. List,
    length(Rest, N),
    append(List, Rest, NList),
    Term =.. NList,
    process_body(Term, From).
process_meta(G, From) :-
    process_body(G, From).

term_member(T, A) :-
    compound(T),
    arg(_, T, A0),
    term_member(A0, A).
term_member(X, X).


                /********************************
                *       INCLUDED MODULES        *
                ********************************/

process_use_module(_Module:_Files) :- !. % loaded in another module
process_use_module([]) :- !.
process_use_module([H|T]) :-
    !,
    process_use_module(H),
    process_use_module(T).
process_use_module(File) :-
    (   current_id(Src),
        xref_public_list(File, _Path, Public, Src)
    ->  assert_import(Public)
    ;   true
    ).

                /********************************
                *       PHASE 1 ASSERTIONS      *
                ********************************/

no_record_called((_,_)).
no_record_called((_;_)).
no_record_called((_|_)).
no_record_called((_->_)).
no_record_called(\+(_)).
no_record_called(!).

assert_called(Var, _) :-
    var(Var),
    !.
assert_called(Goal, _) :-
    no_record_called(Goal),
    !.
assert_called(Goal, From) :-
    called(Goal, From),
    !.
assert_called(M:Goal, From) :-
    nonvar(M),
    x_module(M),
    !,
    assert_called(Goal, From).
assert_called(Goal, From) :-
    functor(Goal, Name, Arity),
    functor(Term, Name, Arity),
    asserta(called(Term, From)).

assert_defined(_Module:_Head) :- !.     % defining in another module.  Bah!
assert_defined(Goal) :-
    defined(Goal),
    !.
assert_defined(Goal) :-
    functor(Goal, Name, Arity),
    functor(Term, Name, Arity),
    asserta(defined(Term)).

assert_import([]) :- !.
assert_import([H|T]) :-
    assert_import(H),
    assert_import(T).
assert_import(Name/Arity) :-
    functor(Term, Name, Arity),
    (   imported(Term)
    ->  true
    ;   asserta(imported(Term))
    ).


assert_dynamic((A, B)) :-
    !,
    assert_dynamic(A),
    assert_dynamic(B).
assert_dynamic(Name/Arity) :-
    functor(Term, Name, Arity),
    assert_defined(Term),
    assert_entity(dynamic(Term)).


assert_require([]).
assert_require([Name/Arity|Rest]) :-
    functor(Head, Name, Arity),
    (   system_predicate(Head)
    ->  true
    ;   assert_import(Head)
    ),
    assert_require(Rest).


                /********************************
                *         POST ANALYSYS         *
                ********************************/

undefined(Head) :-
    defined(Head), !, fail.
undefined(Head) :-
    imported(Head), !, fail.
undefined(Head) :-
    global_predicate(Head), !, fail.
undefined(_:_) :-
    !,
    fail.
undefined(_).

post_analysis :-
    setof(To, unref_call(From, To), Unref),
    assert_entity(unreferenced_call(From, Unref)),
    fail.
post_analysis :-
    current_id(Key),
    unref_pred(Key, Head),
    assert_entity(unreferenced_predicate(Head)),
    fail.
post_analysis.

unref_call(From, To) :-
    called(To, From),
    undefined(To).

unref_pred(Key, Head) :-
    (   x_entity(Key, predicate(Head), _)
    ;   x_entity(Key, xpce_class_local_predicate(Head), _)
    ),
    local_definition(Head),
    \+ called(Head, _),
    \+ x_public(Key, Head).

local_definition(_:_) :-
    !,
    fail.
local_definition(_).





