1/*  Part of SWISH
    2
    3    Author:        Jan Wielemaker
    4    E-mail:        J.Wielemaker@vu.nl
    5    WWW:           http://www.swi-prolog.org
    6    Copyright (c)  2014-2018, VU University Amsterdam
    7			      CWI, Amsterdam
    8    All rights reserved.
    9
   10    Redistribution and use in source and binary forms, with or without
   11    modification, are permitted provided that the following conditions
   12    are met:
   13
   14    1. Redistributions of source code must retain the above copyright
   15       notice, this list of conditions and the following disclaimer.
   16
   17    2. Redistributions in binary form must reproduce the above copyright
   18       notice, this list of conditions and the following disclaimer in
   19       the documentation and/or other materials provided with the
   20       distribution.
   21
   22    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   23    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   24    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   25    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   26    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   27    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   28    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   29    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   30    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   31    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   32    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   33    POSSIBILITY OF SUCH DAMAGE.
   34*/
   35
   36:- module(swish_highlight,
   37	  [ current_highlight_state/2,		% +UUID, -State
   38	    man_predicate_summary/2		% +PI, -Summary
   39	  ]).   40:- use_module(library(debug)).   41:- use_module(library(settings)).   42:- use_module(library(http/http_dispatch)).   43:- use_module(library(http/html_write)).   44:- use_module(library(http/http_json)).   45:- use_module(library(http/http_path), []).   46:- use_module(library(http/http_parameters)).   47:- use_module(library(pairs)).   48:- use_module(library(apply)).   49:- use_module(library(error)).   50:- use_module(library(prolog_xref)).   51:- use_module(library(memfile)).   52:- use_module(library(prolog_colour)).   53:- use_module(library(lazy_lists)).   54:- if(exists_source(library(pldoc/man_index))).   55:- use_module(library(pldoc/man_index)).   56:- elif(exists_source(library(helpidx))).   57:- use_module(library(helpidx), [predicate/5]).   58:- endif.   59
   60http:location(codemirror, swish(cm), []).
   61
   62:- http_handler(codemirror(.),      http_404([]),      [id(cm_highlight)]).   63:- http_handler(codemirror(change), codemirror_change, []).   64:- http_handler(codemirror(tokens), codemirror_tokens, []).   65:- http_handler(codemirror(leave),  codemirror_leave,  []).   66:- http_handler(codemirror(info),   token_info,        []).   67
   68:- setting(swish:editor_max_idle_time, nonneg, 3600,
   69	   "Maximum time we keep a mirror editor around").

   81		 /*******************************
   82		 *	  SHADOW EDITOR		*
   83		 *******************************/

 codemirror_change(+Request)

Handle changes to the codemirror instances. These are sent to us using a POST request. The request a POSTed JSON object containing:

• uuid: string holding the editor's UUID
• change: the change object, which holds:
  • from: Start position as {line:Line, ch:Ch}
  • to: End position
  • removed: list(atom) of removed text
  • text: list(atom) of inserted text
  • origin: what caused this change event
  • next: optional next change event.

Reply is JSON and either 200 with true or 409 indicating that the editor is not known.

  103codemirror_change(Request) :-
  104	call_cleanup(codemirror_change_(Request),
  105		     check_unlocked).
  106
  107codemirror_change_(Request) :-
  108	http_read_json_dict(Request, Change, []),
  109	debug(cm(change), 'Change ~p', [Change]),
  110	atom_string(UUID, Change.uuid),
  111	catch(shadow_editor(Change, TB),
  112	      cm(Reason), true),
  113	(   var(Reason)
  114	->  (	catch(apply_change(TB, Changed, Change.change),
  115		      cm(outofsync), fail)
  116	    ->  mark_changed(TB, Changed),
  117		release_editor(UUID),
  118		reply_json_dict(true)
  119	    ;	destroy_editor(UUID),
  120		change_failed(UUID, outofsync)
  121	    )
  122	;   change_failed(UUID, Reason)
  123	).
  124
  125change_failed(UUID, Reason) :-
  126	reply_json_dict(json{ type:Reason,
  127			      object:UUID
  128			    },
  129			[status(409)]).

 apply_change(+TB, -Changed, +Changes) is det

Note that the argument order is like this to allow for maplist.

Arguments:

Changed

- is left unbound if there are no changes or unified to true if something has changed.

throws

- cm(outofsync) if an inconsistent delete is observed.

  141apply_change(_, _Changed, []) :- !.
  142apply_change(TB, Changed, Change) :-
  143	_{from:From} :< Change,
  144	Line is From.line+1,
  145	memory_file_line_position(TB, Line, From.ch, ChPos),
  146	remove(Change.removed, TB, ChPos, Changed),
  147	insert(Change.text, TB, ChPos, _End, Changed),
  148	(   Next = Change.get(next)
  149	->  apply_change(TB, Changed, Next)
  150	;   true
  151	).
  152
  153remove([], _, _, _) :- !.
  154remove([H|T], TB, ChPos, Changed) :-
  155	string_length(H, Len),
  156	(   T == []
  157	->  DLen is Len
  158	;   DLen is Len+1
  159	),
  160	(   DLen == 0
  161	->  true
  162	;   Changed = true,
  163	    memory_file_substring(TB, ChPos, Len, _, Text),
  164	    (	Text == H
  165	    ->	true
  166	    ;	throw(cm(outofsync))
  167	    ),
  168	    delete_memory_file(TB, ChPos, DLen)
  169	),
  170	remove(T, TB, ChPos, Changed).
  171
  172insert([], _, ChPos, ChPos, _) :- !.
  173insert([H|T], TB, ChPos0, ChPos, Changed) :-
  174	(   H == ""
  175	->  Len	= 0
  176	;   Changed = true,
  177	    string_length(H, Len),
  178	    debug(cm(change_text), 'Insert ~q at ~d', [H, ChPos0]),
  179	    insert_memory_file(TB, ChPos0, H)
  180	),
  181	ChPos1 is ChPos0+Len,
  182	(   T == []
  183	->  ChPos2 = ChPos1
  184	;   debug(cm(change_text), 'Adding newline at ~d', [ChPos1]),
  185	    Changed = true,
  186	    insert_memory_file(TB, ChPos1, '\n'),
  187	    ChPos2 is ChPos1+1
  188	),
  189	insert(T, TB, ChPos2, ChPos, Changed).
  190
  191:- dynamic
  192	current_editor/5,		% UUID, MemFile, Role, Lock, Time
  193	editor_last_access/2,		% UUID, Time
  194	xref_upto_data/1.		% UUID

 create_editor(+UUID, -Editor, +Change) is det

Create a new editor for source UUID from Change. The editor is created in a locked state and must be released using release_editor/1 before it can be publically used.

  202create_editor(UUID, Editor, Change) :-
  203	must_be(atom, UUID),
  204	uuid_like(UUID),
  205	new_memory_file(Editor),
  206	(   RoleString = Change.get(role)
  207	->  atom_string(Role, RoleString)
  208	;   Role = source
  209	),
  210	get_time(Now),
  211	mutex_create(Lock),
  212	with_mutex(swish_create_editor,
  213		   register_editor(UUID, Editor, Role, Lock, Now)), !.
  214create_editor(UUID, Editor, _Change) :-
  215	fetch_editor(UUID, Editor).
  216
  217% editor and lock are left to symbol-GC if this fails.
  218register_editor(UUID, Editor, Role, Lock, Now) :-
  219	\+ current_editor(UUID, _, _, _, _),
  220	mutex_lock(Lock),
  221	asserta(current_editor(UUID, Editor, Role, Lock, Now)).

 current_highlight_state(?UUID, -State) is nondet

Return info on the current highlighter

  227current_highlight_state(UUID,
  228			highlight{data:Editor,
  229				  role:Role,
  230				  created:Created,
  231				  lock:Lock,
  232				  access:Access
  233				 }) :-
  234	current_editor(UUID, Editor, Role, Lock, Created),
  235	(   editor_last_access(Editor, Access)
  236	->  true
  237	;   Access = Created
  238	).

 uuid_like(+UUID) is semidet

Do some sanity checking on the UUID because we use it as a temporary module name and thus we must be quite sure it will not conflict with anything.

  247uuid_like(UUID) :-
  248	split_string(UUID, "-", "", Parts),
  249	maplist(string_length, Parts, [8,4,4,4,12]),
  250	\+ current_editor(UUID, _, _, _, _).

 destroy_editor(+UUID)

Destroy source admin UUID: the shadow text (a memory file), the XREF data and the module used for cross-referencing. The editor must be acquired using fetch_editor/2 before it can be destroyed.

  259destroy_editor(UUID) :-
  260	must_be(atom, UUID),
  261	current_editor(UUID, Editor, _, Lock, _), !,
  262	mutex_unlock(Lock),
  263	retractall(xref_upto_data(UUID)),
  264	retractall(editor_last_access(UUID, _)),
  265	(   xref_source_id(UUID, SourceID)
  266	->  xref_clean(SourceID),
  267	    destroy_state_module(UUID)
  268	;   true
  269	),
  270	% destroy after xref_clean/1 to make xref_source_identifier/2 work.
  271	retractall(current_editor(UUID, Editor, _, _, _)),
  272	free_memory_file(Editor).
  273destroy_editor(_).

 gc_editors

Garbage collect all editors that have not been accessed for 60 minutes.

To be done

- Normally, deleting a highlight state can be done aggressively as it will be recreated on demand. But, coloring a query passes the UUIDs of related sources and as yet there is no way to restore this. We could fix that by replying to the query colouring with the UUIDs for which we do not have sources, after which the client retry the query-color request with all relevant sources.

  288:- dynamic
  289	gced_editors/1.  290
  291editor_max_idle_time(Time) :-
  292	setting(swish:editor_max_idle_time, Time).
  293
  294gc_editors :-
  295	get_time(Now),
  296	(   gced_editors(Then),
  297	    editor_max_idle_time(MaxIdle),
  298	    Now - Then < MaxIdle/3
  299	->  true
  300	;   retractall(gced_editors(_)),
  301	    asserta(gced_editors(Now)),
  302	    fail
  303	).
  304gc_editors :-
  305	editor_max_idle_time(MaxIdle),
  306	forall(garbage_editor(UUID, MaxIdle),
  307	       destroy_garbage_editor(UUID)).
  308
  309garbage_editor(UUID, TimeOut) :-
  310	get_time(Now),
  311	current_editor(UUID, _TB, _Role, _Lock, Created),
  312	Now - Created > TimeOut,
  313	(   editor_last_access(UUID, Access)
  314	->  Now - Access > TimeOut
  315	;   true
  316	).
  317
  318destroy_garbage_editor(UUID) :-
  319	fetch_editor(UUID, _TB), !,
  320	destroy_editor(UUID).
  321destroy_garbage_editor(_).

 fetch_editor(+UUID, -MemFile) is semidet

Fetch existing editor for source UUID. Update the last access time. After success, the editor is locked and must be released using release_editor/1.

  329fetch_editor(UUID, TB) :-
  330	current_editor(UUID, TB, Role, Lock, _),
  331	catch(mutex_lock(Lock), error(existence_error(mutex,_),_), fail),
  332	debug(cm(lock), 'Locked ~p', [UUID]),
  333	(   current_editor(UUID, TB, Role, Lock, _)
  334	->  update_access(UUID)
  335	;   mutex_unlock(Lock)
  336	).
  337
  338release_editor(UUID) :-
  339	current_editor(UUID, _TB, _Role, Lock, _),
  340	debug(cm(lock), 'Unlocked ~p', [UUID]),
  341	mutex_unlock(Lock).
  342
  343check_unlocked :-
  344	check_unlocked(unknown).

 check_unlocked(+Reason)

Verify that all editors locked by this thread are unlocked again.

  351check_unlocked(Reason) :-
  352	thread_self(Me),
  353	current_editor(_UUID, _TB, _Role, Lock, _),
  354	mutex_property(Lock, status(locked(Me, _Count))), !,
  355	unlock(Me, Lock),
  356	print_message(error, locked(Reason, Me)),
  357	assertion(fail).
  358check_unlocked(_).
  359
  360unlock(Me, Lock) :-
  361	mutex_property(Lock, status(locked(Me, _Count))), !,
  362	mutex_unlock(Lock),
  363	unlock(Me, Lock).
  364unlock(_, _).

 update_access(+UUID)

Update the registered last access. We only update if the time is behind for more than a minute.

  371update_access(UUID) :-
  372	get_time(Now),
  373	(   editor_last_access(UUID, Last),
  374	    Now-Last < 60
  375	->  true
  376	;   retractall(editor_last_access(UUID, _)),
  377	    asserta(editor_last_access(UUID, Now))
  378	).
  379
  380:- multifile
  381	prolog:xref_source_identifier/2,
  382	prolog:xref_open_source/2,
  383	prolog:xref_close_source/2.  384
  385prolog:xref_source_identifier(UUID, UUID) :-
  386	current_editor(UUID, _, _, _, _).

 prolog:xref_open_source(+UUID, -Stream)

Open a source. As we cannot open the same source twice we must lock it. As of 7.3.32 this can be done through the prolog:xref_close_source/2 hook. In older versions we get no callback on the close, so we must leave the editor unlocked.

  395:- if(current_predicate(prolog_source:close_source/3)).  396prolog:xref_open_source(UUID, Stream) :-
  397	fetch_editor(UUID, TB),
  398	open_memory_file(TB, read, Stream).
  399
  400prolog:xref_close_source(UUID, Stream) :-
  401	release_editor(UUID),
  402	close(Stream).
  403:- else.  404prolog:xref_open_source(UUID, Stream) :-
  405	fetch_editor(UUID, TB),
  406	open_memory_file(TB, read, Stream),
  407	release_editor(UUID).
  408:- endif.

 codemirror_leave(+Request)

POST handler that deals with destruction of our mirror associated with an editor, as well as the associated cross-reference information.

  416codemirror_leave(Request) :-
  417	call_cleanup(codemirror_leave_(Request),
  418		     check_unlocked).
  419
  420codemirror_leave_(Request) :-
  421	http_read_json_dict(Request, Data, []),
  422	(   atom_string(UUID, Data.get(uuid))
  423	->  debug(cm(leave), 'Leaving editor ~p', [UUID]),
  424	    (	fetch_editor(UUID, _TB)
  425	    ->	destroy_editor(UUID)
  426	    ;	debug(cm(leave), 'No editor for ~p', [UUID])
  427	    )
  428	;   debug(cm(leave), 'No editor?? (data=~p)', [Data])
  429	),
  430	reply_json_dict(true).

 mark_changed(+MemFile, ?Changed) is det

Mark that our cross-reference data might be obsolete

  436mark_changed(MemFile, Changed) :-
  437	(   Changed == true,
  438	    current_editor(UUID, MemFile, _Role, _, _)
  439	->  retractall(xref_upto_data(UUID))
  440	;   true
  441	).

 xref(+UUID) is det

  445xref(UUID) :-
  446	xref_upto_data(UUID), !.
  447xref(UUID) :-
  448	setup_call_cleanup(
  449	    fetch_editor(UUID, _TB),
  450	    ( xref_source_id(UUID, SourceId),
  451	      xref_state_module(UUID, Module),
  452	      xref_source(SourceId,
  453			  [ silent(true),
  454			    module(Module)
  455			  ]),
  456	      asserta(xref_upto_data(UUID))
  457	    ),
  458	    release_editor(UUID)).

 xref_source_id(+Editor, -SourceID) is det

SourceID is the xref source identifier for Editor. As we are using UUIDs we just use the editor.

  465xref_source_id(UUID, UUID).

 xref_state_module(+UUID, -Module) is semidet

True if we must run the cross-referencing in Module. We use a temporary module based on the UUID of the source.

  472xref_state_module(UUID, UUID) :-
  473	(   module_property(UUID, class(temporary))
  474	->  true
  475	;   set_module(UUID:class(temporary)),
  476	    add_import_module(UUID, swish, start),
  477	    maplist(copy_flag(UUID, swish), [var_prefix])
  478	).
  479
  480copy_flag(Module, Application, Flag) :-
  481    current_prolog_flag(Application:Flag, Value), !,
  482    set_prolog_flag(Module:Flag, Value).
  483copy_flag(_, _, _).
  484
  485destroy_state_module(UUID) :-
  486	module_property(UUID, class(temporary)), !,
  487	'$destroy_module'(UUID).
  488destroy_state_module(_).
  489
  490
  491		 /*******************************
  492		 *	  SERVER TOKENS		*
  493		 *******************************/

 codemirror_tokens(+Request)

HTTP POST handler that returns an array of tokens for the given editor.

  500codemirror_tokens(Request) :-
  501	setup_call_catcher_cleanup(
  502	    true,
  503	    codemirror_tokens_(Request),
  504	    Reason,
  505	    check_unlocked(Reason)).
  506
  507codemirror_tokens_(Request) :-
  508	http_read_json_dict(Request, Data, []),
  509	atom_string(UUID, Data.get(uuid)),
  510	debug(cm(tokens), 'Asking for tokens: ~p', [Data]),
  511	(   catch(shadow_editor(Data, TB), cm(Reason), true)
  512	->  (   var(Reason)
  513	    ->	call_cleanup(enriched_tokens(TB, Data, Tokens),
  514			     release_editor(UUID)),
  515		reply_json_dict(json{tokens:Tokens}, [width(0)])
  516	    ;	check_unlocked(Reason),
  517		change_failed(UUID, Reason)
  518	    )
  519	;   reply_json_dict(json{tokens:[[]]})
  520	),
  521	gc_editors.
  522
  523
  524enriched_tokens(TB, _Data, Tokens) :-		% source window
  525	current_editor(UUID, TB, source, _Lock, _), !,
  526	xref(UUID),
  527	server_tokens(TB, Tokens).
  528enriched_tokens(TB, Data, Tokens) :-		% query window
  529	json_source_id(Data.get(sourceID), SourceID), !,
  530	memory_file_to_string(TB, Query),
  531	with_mutex(swish_highlight_query,
  532		   prolog_colourise_query(Query, SourceID, colour_item(TB))),
  533	collect_tokens(TB, Tokens).
  534enriched_tokens(TB, _Data, Tokens) :-
  535	memory_file_to_string(TB, Query),
  536	prolog_colourise_query(Query, module(swish), colour_item(TB)),
  537	collect_tokens(TB, Tokens).

 json_source_id(+Input, -SourceID)

Translate the Input, which is either a string or a list of strings into an atom or list of atoms. Older versions of SWI-Prolog only accept a single atom source id.

  545:- if(current_predicate(prolog_colour:to_list/2)).  546json_source_id(StringList, SourceIDList) :-
  547	is_list(StringList),
  548	StringList \== [], !,
  549	maplist(string_source_id, StringList, SourceIDList).
  550:- else.				% old version (=< 7.3.7)
  551json_source_id([String|_], SourceID) :-
  552	maplist(string_source_id, String, SourceID).
  553:- endif.  554json_source_id(String, SourceID) :-
  555	string(String),
  556	string_source_id(String, SourceID).
  557
  558string_source_id(String, SourceID) :-
  559	atom_string(SourceID, String),
  560	(   fetch_editor(SourceID, _TB)
  561	->  release_editor(SourceID)
  562	;   true
  563	).

 shadow_editor(+Data, -MemoryFile) is det

Get our shadow editor:

1. If we have one, it is updated from either the text or the changes.
2. If we have none, but there is a text property, create one from the text.
3. If there is a role property, create an empty one.

This predicate fails if the server thinks we have an editor with state that must be reused, but this is not true (for example because we have been restarted).

throws

- cm(existence_error) if the target editor did not exist

- cm(out_of_sync) if the changes do not apply due to an internal error or a lost message.

  583shadow_editor(Data, TB) :-
  584	atom_string(UUID, Data.get(uuid)),
  585	setup_call_catcher_cleanup(
  586	    fetch_editor(UUID, TB),
  587	    once(update_editor(Data, UUID, TB)),
  588	    Catcher,
  589	    cleanup_update(Catcher, UUID)), !.
  590shadow_editor(Data, TB) :-
  591	Text = Data.get(text), !,
  592	atom_string(UUID, Data.uuid),
  593	create_editor(UUID, TB, Data),
  594	debug(cm(change), 'Create editor for ~p', [UUID]),
  595	debug(cm(change_text), 'Initialising editor to ~q', [Text]),
  596	insert_memory_file(TB, 0, Text).
  597shadow_editor(Data, TB) :-
  598	_{role:_} :< Data, !,
  599	atom_string(UUID, Data.uuid),
  600	create_editor(UUID, TB, Data).
  601shadow_editor(_Data, _TB) :-
  602	throw(cm(existence_error)).
  603
  604update_editor(Data, _UUID, TB) :-
  605	Text = Data.get(text), !,
  606	size_memory_file(TB, Size),
  607	delete_memory_file(TB, 0, Size),
  608	insert_memory_file(TB, 0, Text),
  609	mark_changed(TB, true).
  610update_editor(Data, UUID, TB) :-
  611	Changes = Data.get(changes), !,
  612	(   debug(cm(change), 'Patch editor for ~p', [UUID]),
  613	    maplist(apply_change(TB, Changed), Changes)
  614	->  true
  615	;   throw(cm(out_of_sync))
  616	),
  617	mark_changed(TB, Changed).
  618
  619cleanup_update(exit, _) :- !.
  620cleanup_update(_, UUID) :-
  621	release_editor(UUID).
  622
  623:- thread_local
  624	token/3.

 show_mirror(+Role) is det

 server_tokens(+Role) is det

These predicates help debugging the server side. show_mirror/0 displays the text the server thinks is in the client editor. The predicate server_tokens/1 dumps the token list.

Arguments:

Role	- is one of source or query, expressing the role of the editor in the SWISH UI.

  636:- public
  637	show_mirror/1,
  638	server_tokens/1.  639
  640show_mirror(Role) :-
  641	current_editor(_UUID, TB, Role, _Lock, _), !,
  642	memory_file_to_string(TB, String),
  643	write(user_error, String).
  644
  645server_tokens(Role) :-
  646	current_editor(_UUID, TB, Role, _Lock, _), !,
  647	enriched_tokens(TB, _{}, Tokens),
  648	print_term(Tokens, [output(user_error)]).

 server_tokens(+TextBuffer, -Tokens) is det

Arguments:

Tokens

- is a nested list of Prolog JSON terms. Each group represents the tokens found in a single toplevel term.

  655server_tokens(TB, GroupedTokens) :-
  656	current_editor(UUID, TB, _Role, _Lock, _),
  657	setup_call_cleanup(
  658	    open_memory_file(TB, read, Stream),
  659	    ( set_stream_file(TB, Stream),
  660	      prolog_colourise_stream(Stream, UUID, colour_item(TB))
  661	    ),
  662	    close(Stream)),
  663	collect_tokens(TB, GroupedTokens).
  664
  665collect_tokens(TB, GroupedTokens) :-
  666	findall(Start-Token, json_token(TB, Start, Token), Pairs),
  667	keysort(Pairs, Sorted),
  668	pairs_values(Sorted, Tokens),
  669	group_by_term(Tokens, GroupedTokens).
  670
  671set_stream_file(_,_).			% TBD

 group_by_term(+Tokens, -Nested) is det

Group the tokens by input term. This simplifies incremental updates of the token list at the client sides as well as re-syncronizing. This predicate relies on the fullstop token that is emitted at the end of each input term.

  680group_by_term([], []) :- !.
  681group_by_term(Flat, [Term|Grouped]) :-
  682	take_term(Flat, Term, Rest),
  683	group_by_term(Rest, Grouped).
  684
  685take_term([], [], []).
  686take_term([H|T0], [H|T], R) :-
  687	(   ends_term(H.get(type))
  688	->  T = [],
  689	    R = T0
  690	;   take_term(T0, T, R)
  691	).
  692
  693ends_term(fullstop).
  694ends_term(syntax_error).

 json_token(+TB, -Start, -JSON) is nondet

Extract the stored terms.

To be done

- We could consider to collect the attributes in the colour_item/4 callback and maintain a global variable instead of using assert/retract. Most likely that would be faster. Need to profile to check the bottleneck.

  705json_token(TB, Start, Token) :-
  706	retract(token(Style, Start0, Len)),
  707	debug(color, 'Trapped ~q.', [token(Style, Start0, Len)]),
  708	(   atomic_special(Style, Start0, Len, TB, Type, Attrs)
  709	->  Start = Start0
  710	;   style(Style, Type0, Attrs0)
  711	->  (   Type0 = StartType-EndType
  712	    ->	(   Start = Start0,
  713		    Type  = StartType
  714		;   Start is Start0+Len-1,
  715		    Type  = EndType
  716		)
  717	    ;	Type = Type0,
  718		Start = Start0
  719	    ),
  720	    json_attributes(Attrs0, Attrs, TB, Start0, Len)
  721	),
  722	dict_create(Token, json, [type(Type)|Attrs]).
  723
  724atomic_special(atom, Start, Len, TB, Type, Attrs) :-
  725	memory_file_substring(TB, Start, 1, _, FirstChar),
  726	(   FirstChar == "'"
  727	->  Type = qatom,
  728	    Attrs = []
  729	;   char_type(FirstChar, upper)
  730	->  Type = uatom,			% var_prefix in effect
  731	    Attrs = []
  732	;   Type = atom,
  733	    (   Len =< 5			% solo characters, neck, etc.
  734	    ->  memory_file_substring(TB, Start, Len, _, Text),
  735	        Attrs = [text(Text)]
  736	    ;   Attrs = []
  737	    )
  738	).
  739
  740json_attributes([], [], _, _, _).
  741json_attributes([H0|T0], Attrs, TB, Start, Len) :-
  742	json_attribute(H0, Attrs, T, TB, Start, Len), !,
  743	json_attributes(T0, T, TB, Start, Len).
  744json_attributes([_|T0], T, TB, Start, Len) :-
  745	json_attributes(T0, T, TB, Start, Len).
  746
  747json_attribute(text, [text(Text)|T], T, TB, Start, Len) :- !,
  748	memory_file_substring(TB, Start, Len, _, Text).
  749json_attribute(line(File:Line), [line(Line),file(File)|T], T, _, _, _) :- !.
  750json_attribute(Term, [Term|T], T, _, _, _).
  751
  752colour_item(_TB, Style, Start, Len) :-
  753	(   style(Style)
  754	->  assertz(token(Style, Start, Len))
  755	;   debug(color, 'Ignored ~q.', [token(Style, Start, Len)])
  756	).

 style(+StyleIn) is semidet

 style(+StyleIn, -SWISHType:atomOrPair, -Attributes:list)

Declare that we map StyleIn as generated by library(prolog_colour) into a token of type SWISHType, providing additional context information based on Attributes. Elements of Attributes are terms of the form Name(Value) or the atom text. The latter is mapped to text(String), where String contains the text that matches the token character range.

The resulting JSON token object has a property type, containing the SWISHType and the properties defined by Attributes.

Additional translations can be defined by adding rules for the multifile predicate style/3. The base type, which refers to the type generated by the SWISH tokenizer must be specified by adding an attribute base(BaseType). For example, if the colour system classifies an atom as refering to a database column, library(prolog_colour) may emit db_column(Name) and the following rule should ensure consistent mapping:

swish_highlight:style(db_column(Name),
                      db_column, [text, base(atom)]).

  785:- multifile
  786	style/3.  787
  788style(Style) :-
  789	style(Style, _, _).
  790
  791style(neck(Neck),     neck, [ text(Text) ]) :-
  792	neck_text(Neck, Text).
  793style(head(Class, Head), Type, [ text, arity(Arity) ]) :-
  794	goal_arity(Head, Arity),
  795	head_type(Class, Type).
  796style(goal_term(_Class, Goal), var, []) :-
  797	var(Goal), !.
  798style(goal_term(Class, {_}), brace_term_open-brace_term_close,
  799      [ name({}), arity(1) | More ]) :-
  800	goal_type(Class, _Type, More).
  801style(goal(Class, Goal), Type, [ text, arity(Arity) | More ]) :-
  802	Goal \= {_},
  803	goal_arity(Goal, Arity),
  804	goal_type(Class, Type, More).
  805style(file_no_depend(Path), file_no_depends,		   [text, path(Path)]).
  806style(file(Path),	 file,				   [text, path(Path)]).
  807style(nofile,		 nofile,			   [text]).
  808style(option_name,	 option_name,			   [text]).
  809style(no_option_name,	 no_option_name,		   [text]).
  810style(flag_name(_Flag),	 flag_name,			   [text]).
  811style(no_flag_name(_Flag), no_flag_name,		   [text]).
  812style(fullstop,		 fullstop,			   []).
  813style(var,		 var,				   [text]).
  814style(singleton,	 singleton,			   [text]).
  815style(string,		 string,			   []).
  816style(codes,		 codes,				   []).
  817style(chars,		 chars,				   []).
  818style(atom,		 atom,				   []).
  819style(format_string,	 format_string,			   []).
  820style(meta(_Spec),	 meta,				   []).
  821style(op_type(_Type),	 op_type,			   [text]).
  822style(functor,		 functor,			   [text]).
  823style(control,		 control,			   [text]).
  824style(delimiter,	 delimiter,			   [text]).
  825style(identifier,	 identifier,			   [text]).
  826style(module(_Module),   module,			   [text]).
  827style(error,		 error,				   [text]).
  828style(constraint(Set),   constraint,			   [text, set(Set)]).
  829style(type_error(Expect), error,		      [text,expected(Expect)]).
  830style(syntax_error(_Msg,_Pos), syntax_error,		   []).
  831style(instantiation_error, instantiation_error,	           [text]).
  832style(predicate_indicator, atom,			   [text]).
  833style(predicate_indicator, atom,			   [text]).
  834style(arity,		 int,				   []).
  835style(int,		 int,				   []).
  836style(float,		 float,				   []).
  837style(qq(open),		 qq_open,			   []).
  838style(qq(sep),		 qq_sep,			   []).
  839style(qq(close),	 qq_close,			   []).
  840style(qq_type,		 qq_type,			   [text]).
  841style(dict_tag,		 tag,				   [text]).
  842style(dict_key,		 key,				   [text]).
  843style(dict_sep,		 sep,				   []).
  844style(func_dot,		 atom,				   [text(.)]).
  845style(dict_return_op,	 atom,				   [text(:=)]).
  846style(dict_function(F),  dict_function,			   [text(F)]).
  847style(empty_list,	 list_open-list_close,		   []).
  848style(list,		 list_open-list_close,		   []).
  849style(dcg(terminal),	 list_open-list_close,		   []).
  850style(dcg(string),	 string_terminal,		   []).
  851style(dcg(plain),	 brace_term_open-brace_term_close, []).
  852style(brace_term,	 brace_term_open-brace_term_close, []).
  853style(dict_content,	 dict_open-dict_close,             []).
  854style(expanded,		 expanded,			   [text]).
  855style(comment_string,	 comment_string,		   []). % up to 7.3.33
  856style(comment(string),	 comment_string,		   []). % after 7.3.33
  857style(ext_quant,	 ext_quant,			   []).
  858style(unused_import,	 unused_import,			   [text]).
  859style(undefined_import,	 undefined_import,		   [text]).
  860					% from library(http/html_write)
  861style(html(_Element),	 html,				   []).
  862style(entity(_Element),	 entity,			   []).
  863style(html_attribute(_), html_attribute,		   []).
  864style(sgml_attr_function,sgml_attr_function,		   []).
  865style(html_call,	 html_call,			   [text]).  % \Rule
  866style(html_raw,		 html_raw,			   [text]).  % \List
  867style(http_location_for_id(_), http_location_for_id,       []).
  868style(http_no_location_for_id(_), http_no_location_for_id, []).
  869					% XPCE support
  870style(method(send),	 xpce_method,			   [text]).
  871style(method(get),	 xpce_method,			   [text]).
  872style(class(built_in,_Name),	  xpce_class_built_in,	   [text]).
  873style(class(library(File),_Name), xpce_class_lib,	   [text, file(File)]).
  874style(class(user(File),_Name),	  xpce_class_user,	   [text, file(File)]).
  875style(class(user,_Name),	  xpce_class_user,	   [text]).
  876style(class(undefined,_Name),	  xpce_class_undef,	   [text]).
  877
  878neck_text(clause,       (:-)).
  879neck_text(grammar_rule, (-->)).
  880neck_text(method(send), (:->)).
  881neck_text(method(get),  (:<-)).
  882neck_text(directive,    (:-)).
  883
  884head_type(exported,	 head_exported).
  885head_type(public(_),	 head_public).
  886head_type(extern(_),	 head_extern).
  887head_type(extern(_,_),	 head_extern).
  888head_type(dynamic,	 head_dynamic).
  889head_type(multifile,	 head_multifile).
  890head_type(unreferenced,	 head_unreferenced).
  891head_type(hook,		 head_hook).
  892head_type(meta,		 head_meta).
  893head_type(constraint(_), head_constraint).
  894head_type(imported,	 head_imported).
  895head_type(built_in,	 head_built_in).
  896head_type(iso,		 head_iso).
  897head_type(def_iso,	 head_def_iso).
  898head_type(def_swi,	 head_def_swi).
  899head_type(_,		 head).
  900
  901goal_type(built_in,	      goal_built_in,	 []).
  902goal_type(imported(File),     goal_imported,	 [file(File)]).
  903goal_type(autoload(File),     goal_autoload,	 [file(File)]).
  904goal_type(global,	      goal_global,	 []).
  905goal_type(undefined,	      goal_undefined,	 []).
  906goal_type(thread_local(Line), goal_thread_local, [line(Line)]).
  907goal_type(dynamic(Line),      goal_dynamic,	 [line(Line)]).
  908goal_type(multifile(Line),    goal_multifile,	 [line(Line)]).
  909goal_type(expanded,	      goal_expanded,	 []).
  910goal_type(extern(_),	      goal_extern,	 []).
  911goal_type(extern(_,_),	      goal_extern,	 []).
  912goal_type(recursion,	      goal_recursion,	 []).
  913goal_type(meta,		      goal_meta,	 []).
  914goal_type(foreign(_),	      goal_foreign,	 []).
  915goal_type(local(Line),	      goal_local,	 [line(Line)]).
  916goal_type(constraint(Line),   goal_constraint,	 [line(Line)]).
  917goal_type(not_callable,	      goal_not_callable, []).

 goal_arity(+Goal, -Arity) is det

Get the arity of a goal safely in SWI7

  923goal_arity(Goal, Arity) :-
  924	(   compound(Goal)
  925	->  compound_name_arity(Goal, _, Arity)
  926	;   Arity = 0
  927	).
  928
  929		 /*******************************
  930		 *	 HIGHLIGHT CONFIG	*
  931		 *******************************/
  932
  933:- multifile
  934	swish_config:config/2,
  935	css/3.				% ?Context, ?Selector, -Attributes

 swish_config:config(-Name, -Styles) is nondet

Provides the object config.swish.style, a JSON object that maps style properties of user-defined extensions of library(prolog_colour). This info is used by the server-side colour engine to populate the CodeMirror styles.

To be done

- Provide summary information

  946swish_config:config(cm_style, Styles) :-
  947	findall(Name-Style, highlight_style(Name, Style), Pairs),
  948	keysort(Pairs, Sorted),
  949	remove_duplicate_styles(Sorted, Unique),
  950	dict_pairs(Styles, json, Unique).
  951swish_config:config(cm_hover_style, Styles) :-
  952	findall(Sel-Attrs, css_dict(hover, Sel, Attrs), Pairs),
  953	dict_pairs(Styles, json, Pairs).
  954
  955remove_duplicate_styles([], []).
  956remove_duplicate_styles([H|T0], [H|T]) :-
  957	H = K-_,
  958	remove_same(K, T0, T1),
  959	remove_duplicate_styles(T1, T).
  960
  961remove_same(K, [K-_|T0], T) :- !,
  962	remove_same(K, T0, T).
  963remove_same(_, Rest, Rest).
  964
  965highlight_style(StyleName, Style) :-
  966	style(Term, StyleName, _),
  967	atom(StyleName),
  968	(   prolog_colour:style(Term, Attrs0)
  969        ->  maplist(css_style, Attrs0, Attrs),
  970	    dict_create(Style, json, Attrs)
  971	).
  972
  973css_style(bold(true),      'font-weight'(bold)) :- !.
  974css_style(underline(true), 'text-decoration'(underline)) :- !.
  975css_style(colour(Name), color(RGB)) :-
  976	x11_color(Name, R, G, B),
  977	format(atom(RGB), '#~|~`0t~16r~2+~`0t~16r~2+~`0t~16r~2+', [R,G,B]).
  978css_style(Style, Style).

 x11_color(+Name, -R, -G, -B)

True if RGB is the color for the named X11 color.

  984x11_color(Name, R, G, B) :-
  985	(   x11_colors_done
  986	->  true
  987	;   with_mutex(swish_highlight, load_x11_colours)
  988	),
  989	x11_color_cache(Name, R, G, B).
  990
  991:- dynamic
  992	x11_color_cache/4,
  993	x11_colors_done/0.  994
  995load_x11_colours :-
  996	x11_colors_done, !.
  997load_x11_colours :-
  998	source_file(load_x11_colours, File),
  999	file_directory_name(File, Dir),
 1000	directory_file_path(Dir, 'rgb.txt', RgbFile),
 1001	setup_call_cleanup(
 1002	    open(RgbFile, read, In),
 1003	    ( lazy_list(lazy_read_lines(In, [as(string)]), List),
 1004	      maplist(assert_colour, List)
 1005	    ),
 1006	    close(In)),
 1007	asserta(x11_colors_done).
 1008
 1009assert_colour(String) :-
 1010	split_string(String, "\s\t\r", "\s\t\r", [RS,GS,BS|NameParts]),
 1011	number_string(R, RS),
 1012	number_string(G, GS),
 1013	number_string(B, BS),
 1014	atomic_list_concat(NameParts, '_', Name0),
 1015	downcase_atom(Name0, Name),
 1016	assertz(x11_color_cache(Name, R, G, B)).
 1017
 1018:- catch(initialization(load_x11_colours, prepare_state), _, true).

 css(?Context, ?Selector, -Style) is nondet

Multifile hook to define additional style to apply in a specific context. Currently defined contexts are:

hover

Used for CodeMirror hover extension.

Arguments:

Selector	- is a CSS selector, which is refined by Context
Style	- is a list of Name(Value) terms.

 1031css_dict(Context, Selector, Style) :-
 1032	css(Context, Selector, Attrs0),
 1033	maplist(css_style, Attrs0, Attrs),
 1034	dict_create(Style, json, Attrs).
 1035
 1036
 1037		 /*******************************
 1038		 *	       INFO		*
 1039		 *******************************/
 1040
 1041:- multifile
 1042	prolog:predicate_summary/2.

 token_info(+Request)

HTTP handler that provides information about a token.

 1048token_info(Request) :-
 1049	http_parameters(Request, [], [form_data(Form)]),
 1050	maplist(type_convert, Form, Values),
 1051	dict_create(Token, token, Values),
 1052	reply_html_page(plain,
 1053			title('token info'),
 1054			\token_info_or_none(Token)).
 1055
 1056type_convert(Name=Atom, Name=Number) :-
 1057	atom_number(Atom, Number), !.
 1058type_convert(NameValue, NameValue).
 1059
 1060
 1061token_info_or_none(Token) -->
 1062	token_info(Token), !.
 1063token_info_or_none(_) -->
 1064	html(span(class('token-noinfo'), 'No info available')).

 token_info(+Token:dict)// is det

Generate HTML, providing details about Token. Token is a dict, providing the enriched token as defined by style/3. This multifile non-terminal can be hooked to provide details for user defined style extensions.

 1073:- multifile token_info//1. 1074
 1075token_info(Token) -->
 1076	{ _{type:Type, text:Name, arity:Arity} :< Token,
 1077	  goal_type(_, Type, _), !,
 1078	  ignore(token_predicate_module(Token, Module)),
 1079	  text_arity_pi(Name, Arity, PI),
 1080	  predicate_info(Module:PI, Info)
 1081	},
 1082	pred_info(Info).
 1083
 1084pred_info([]) -->
 1085	html(span(class('pred-nosummary'), 'No help available')).
 1086pred_info([Info|_]) -->			% TBD: Ambiguous
 1087	(pred_tags(Info)     -> [];[]),
 1088	(pred_summary(Info)  -> [];[]).
 1089
 1090pred_tags(Info) -->
 1091	{ Info.get(iso) == true },
 1092	html(span(class('pred-tag'), 'ISO')).
 1093
 1094pred_summary(Info) -->
 1095	html(span(class('pred-summary'), Info.get(summary))).

 token_predicate_module(+Token, -Module) is semidet

Try to extract the module from the token.

 1101token_predicate_module(Token, Module) :-
 1102	source_file_property(Token.get(file), module(Module)), !.
 1103
 1104text_arity_pi('[', 2, consult/1) :- !.
 1105text_arity_pi(']', 2, consult/1) :- !.
 1106text_arity_pi(Name, Arity, Name/Arity).

 predicate_info(+PI, -Info:list(dict)) is det

Info is a list of dicts providing details about predicates that match PI. Fields in dict are:

module:Atom

Module of the predicate

name:Atom

Name of the predicate

arity:Integer

Arity of the predicate

summary:Text

Summary text extracted from the system manual or PlDoc

iso:Boolean

Presend and true if the predicate is an ISO predicate

 1125predicate_info(PI, Info) :-
 1126	PI = Module:Name/Arity,
 1127	findall(Dict,
 1128		( setof(Key-Value,
 1129			predicate_info(PI, Key, Value),
 1130			Pairs),
 1131		  dict_pairs(Dict, json,
 1132			     [ module - Module,
 1133			       name   - Name,
 1134			       arity  - Arity
 1135			     | Pairs
 1136			     ])
 1137		),
 1138		Info).

 predicate_info(?PI, -Key, -Value) is nondet

Find information about predicates from the system, manual and PlDoc. First, we deal with ISO predicates that cannot be redefined and are documented in the manual. Next, we deal with predicates that are documented in the manual.

bug

- : Handling predicates documented in the manual is buggy because their definition may be overruled by the user. We probably must include the file into the equation.

 1151					% ISO predicates
 1152predicate_info(Module:Name/Arity, Key, Value) :-
 1153	functor(Head, Name, Arity),
 1154	predicate_property(system:Head, iso), !,
 1155	ignore(Module = system),
 1156	(   man_predicate_summary(Name/Arity, Summary),
 1157	    Key = summary,
 1158	    Value = Summary
 1159	;   Key = iso,
 1160	    Value = true
 1161	).
 1162predicate_info(PI, summary, Summary) :-
 1163	PI = Module:Name/Arity,
 1164
 1165	(   man_predicate_summary(Name/Arity, Summary)
 1166	->  true
 1167	;   Arity >= 2,
 1168	    DCGArity is Arity - 2,
 1169	    man_predicate_summary(Name//DCGArity, Summary)
 1170	->  true
 1171	;   prolog:predicate_summary(PI, Summary)
 1172	->  true
 1173	;   Arity >= 2,
 1174	    DCGArity is Arity - 2,
 1175	    prolog:predicate_summary(Module:Name/DCGArity, Summary)
 1176	).
 1177
 1178:- if(current_predicate(man_object_property/2)). 1179man_predicate_summary(PI, Summary) :-
 1180    man_object_property(PI, summary(Summary)).
 1181:- elif(current_predicate(predicate/5)). 1182man_predicate_summary(Name/Arity, Summary) :-
 1183    predicate(Name, Arity, Summary, _, _).
 1184:- else. 1185man_predicate_summary(_, _) :-
 1186    fail.
 1187:- endif.