1/*  Part of SWI-Prolog
   2
   3    Author:        Jan Wielemaker
   4    E-mail:        J.Wielemaker@vu.nl
   5    WWW:           http://www.swi-prolog.org
   6    Copyright (c)  2013, VU University 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(prolog_console_input,
  36          [
  37          ]).
  38:- use_module(library(lists)).
  39
  40:- multifile
  41    prolog:complete_input/4.
  42
  43%!  prolog:complete_input(+BeforeCursor, +AfterCursor,
  44%!                        -Delete, -Completions) is det.
  45%
  46%   Compute    auto    completions    for      the     input    line
  47%   BeforeCursor+AfterCursor.
  48%
  49%   @arg    Delete is an atom or string representing the text that is
  50%           replaced by the completion
  51%   @arg    Completions is a list of elements of this shape:
  52%
  53%             - Atom
  54%             Used for a plain completion without comment
  55%             - Atom-Comment
  56%             Used for a completion with comment.  This will be
  57%             used for predicates.
  58
  59prolog:complete_input(Before, _After, Delete, Completions) :-
  60    string_codes(Before, Chars),
  61    reverse(Chars, BeforeRev),
  62    complete(BeforeRev, Delete, Completions).
  63
  64complete(BeforeRev, Prefix, Files) :-   % complete files
  65    phrase(file_prefix(Prefix), BeforeRev, _),
  66    !,
  67    atom_concat(Prefix, '*', Pattern),
  68    expand_file_name(Pattern, Files).
  69complete(BeforeRev, Prefix, Atoms) :-   % complete atoms
  70    phrase(atom_prefix(Prefix), BeforeRev, _),
  71    !,
  72    '$atom_completions'(Prefix, Atoms).
  73
  74%!  atom_prefix(-Prefix) is det.
  75
  76atom_prefix(Prefix) -->
  77    atom_chars(RevString),
  78    { reverse(RevString, String),
  79      string_codes(Prefix, String) % do not create an atom
  80    }.
  81
  82atom_chars([H|T]) --> atom_char(H), !, atom_chars(T).
  83atom_chars([]) --> [].
  84
  85atom_char(C) --> [C], { atom_char(C) }.
  86
  87atom_char(C) :- code_type(C, csym).
  88
  89%!  file_prefix(-Prefix)// is semidet.
  90%
  91%   True when the part before the cursor looks like a file name.
  92
  93file_prefix(Prefix) -->
  94    file_chars(RevString), "'",
  95    { reverse(RevString, String),
  96      atom_codes(Prefix, String)
  97    }.
  98
  99file_chars([H|T]) --> file_char(H), !, file_chars(T).
 100file_chars([]) --> [].
 101
 102file_char(C) --> [C], { file_char(C) }.
 103
 104file_char(C) :- code_type(C, csym).
 105file_char(0'/).
 106file_char(0'.).
 107file_char(0'-).
 108file_char(0'~).
 109:- if(current_prolog_flag(windows,true)).
 110file_char(0':).
 111file_char(0'\s).
 112:- endif.