1/* Part of sCASP 2 3 Author: Jan Wielemaker 4 E-mail: jan@swi-prolog.org 5 Copyright (c) 2021, SWI-Prolog Solutions b.v. 6 All rights reserved. 7 8 Redistribution and use in source and binary forms, with or without 9 modification, are permitted provided that the following conditions 10 are met: 11 12 1. Redistributions of source code must retain the above copyright 13 notice, this list of conditions and the following disclaimer. 14 15 2. Redistributions in binary form must reproduce the above copyright 16 notice, this list of conditions and the following disclaimer in 17 the documentation and/or other materials provided with the 18 distribution. 19 20 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 28 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 30 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 POSSIBILITY OF SUCH DAMAGE. 32*/ 33 34:- module(scasp_html_text, 35 [ emit_as//2, 36 emitting_as/1, 37 emit//1, 38 fixup_layout/2 % +Tokens,-Final 39 ]). 40:- use_module(library(dcg/high_order)). 41:- use_module(library(http/html_write)). 42:- use_module(library(apply)). 43:- use_module(library(error)). 44:- use_module(library(lists)). 45 46:- html_meta 47 emit_as(html, +, ?, ?), 48 emit(html, ?, ?).

Switch between HTML and plain text output

Allow generating plain (colored) text from html//1 compatible calls. We do this in two steps, first creating a token list and next deal with state using fixup_layout/2. It would be nicer if we could avoid the latter step, but we need to maintain state such as indentation and attributes and we cannot pass that around in an additional argument as there are calls that do not know about this transformation in between.

The translation is highly specific for the calls done in html.pl. If you change CSS classes or the HTML DOM produced you likely have to make changes here as well.

To be done: - It might be better to maintain a stack of parent DOM nodes in a backtrackable global variable to deal with the state. */

91emit(M:Spec) --> 92 { emitting_as(plain) 93 }, 94 !, 95 emit(Spec, M). 96emit(Spec) --> 97 html(Spec). 98 99emit(Var, _) --> 100 { var(Var) }, 101 !, 102 [ '~p'-[Var] ]. 103emit(List, M) --> 104 { is_list(List) }, 105 !, 106 sequence(emit_r(M), List). 107emit(\Goal, M) --> 108 { callable(Goal) }, 109 !, 110 call(M:Goal). 111emit(Element, _M) --> 112 { is_machine(Element) 113 }, 114 !. 115emit(var(Name), _M) --> 116 !, 117 [ ansi(fg(magenta), '~w', [Name]) ]. 118emit(span(Content), M) --> 119 !, 120 emit(Content, M). 121emit(span(Attrs, Content), M) --> 122 !, 123 ( classes_ansi(Attrs) 124 -> emit(Content, M), 125 [pop_ansi] 126 ; emit(Content, M) 127 ). 128emit(div(Attrs, Content), M) --> 129 { has_class(Attrs, 'scasp-query-literal') }, 130 !, 131 [indent(3)], 132 emit(Content, M), 133 [indent(-3), nl(1)]. 134emit(div(Attrs, Content), M) --> 135 !, 136 classes_pre_lines(Attrs), 137 ( classes_bullet(Attrs) 138 -> emit(Content, M), 139 [bullet(pop)] 140 ; emit(Content, M) 141 ), 142 [nl(1)]. 143emit(div(Content), M) --> 144 !, 145 emit(Content, M), 146 [nl(1)]. 147emit(ul(_Attrs, LIs), M) --> 148 !, 149 [indent(3)], 150 emit(LIs, M), 151 [indent(-3)]. 152emit(li(_Attrs, Content), M) --> 153 !, 154 [bullet], 155 emit(Content, M), 156 [nl(1)]. 157emit(li(Content), M) --> 158 !, 159 [bullet], 160 emit(Content, M), 161 [nl(1)]. 162emit(Fmt-Args, _M) --> 163 !, 164 [ Fmt-Args ]. 165emit(Atomic, _M) --> 166 !, 167 [ '~w'-[Atomic] ]. 168 169emit_r(M, Spec) --> 170 emit(Spec, M). 171 172is_machine(Element) :- 173 compound(Element), 174 functor(Element, _, 2), 175 arg(1, Element, Attrs), 176 has_class(Attrs, machine). 177 178classes_ansi(Attrs) --> 179 { classes(Attrs, Classes), 180 include(truth_class, Classes, TClasses), 181 sort(TClasses, TClassesS), 182 classes_ansi_map(TClassesS, Ansi) 183 }, 184 !, 185 [ansi(Ansi)]. 186 187classes_bullet(Attrs) --> 188 { has_class(Attrs, 'scasp-justification') }, 189 !, 190 [ bullet('') ]. 191 192classes_pre_lines(Attrs) --> 193 { has_class(Attrs, 'scasp-predicate') }, 194 !, 195 [ nl(1) ]. 196classes_pre_lines(_) --> 197 []. 198 199has_class(Attrs, Class) :- 200 classes(Attrs, Classes), 201 memberchk(Class, Classes). 202 203classes(Attrs, Classes) :- 204 ( is_list(Attrs) 205 -> include(is_class, Attrs, ClassAttrs), 206 maplist(arg(1), ClassAttrs, Classes0), 207 flatten(Classes0, Classes) 208 ; Attrs = class(Classes0), 209 ( is_list(Classes0) 210 -> Classes = Classes0 211 ; Classes = [Classes0] 212 ) 213 ). 214 215is_class(class(_)). 216 217truth_class(pos). 218truth_class(not). 219truth_class(neg). 220 221classes_ansi_map([neg], [fg(red), bold]). 222%classes_ansi_map([neg,not], []). 223classes_ansi_map([not], [fg(red)]). 224classes_ansi_map([pos], [bold]).

230:- det(fixup_layout/2). 231 232fixup_layout(Tokens, Final) :- 233 fixup_layout(Tokens, Final, 234 #{ indent:0, 235 ansi:[], ansi_stack:[], 236 bullet:['\u2022'] 237 }). 238 239fixup_layout([], [], _). 240fixup_layout([nl(Lines0)|T0], Final, State) :- 241 !, 242 Indent0 = State.indent, 243 join_blank_lines(T0, T1, Indent0, Indent, Lines0, Lines), 244 skip_lines(Lines, Final, T), 245 ( T1 == [] 246 -> T = [] 247 ; Indent > 0 248 -> format(atom(I), '~t~*|', [Indent]), 249 T = [I|T2] 250 ; T = T2 251 ), 252 fixup_layout(T1, T2, State.put(indent, Indent)). 253fixup_layout([indent(N)|T0], T, State) :- 254 !, 255 Indent is State.indent+N, 256 indent(Indent, T, T1), 257 fixup_layout(T0, T1, State.put(indent, Indent)). 258fixup_layout([bullet|T0], T, State) :- 259 !, 260 [Bullet|_] = State.bullet, 261 ( Bullet == '' 262 -> fixup_layout(T0, T, State) 263 ; T = ['~w '-[Bullet]|T1], 264 fixup_layout(T0, T1, State) 265 ). 266fixup_layout([bullet(Bullet)|T0], T, State) :- 267 !, 268 Stack = State.bullet, 269 ( Bullet == pop 270 -> Stack = [_|NewStack] 271 ; NewStack = [Bullet|Stack] 272 ), 273 fixup_layout(T0, T, State.put(bullet, NewStack)). 274fixup_layout([ansi(Attrs)|T0], T, State) :- 275 !, 276 Old = State.ansi, 277 Stack = State.ansi_stack, 278 append(Attrs, Old, New), 279 fixup_layout(T0, T, State.put(#{ansi:New, ansi_stack:[Old|Stack]})). 280fixup_layout([pop_ansi|T0], T, State) :- 281 !, 282 [Old|Stack] = State.ansi_stack, 283 fixup_layout(T0, T, State.put(#{ansi:Old, ansi_stack:Stack})). 284fixup_layout([H0|T0], [H|T], State) :- 285 fixup_element(H0, H, State.ansi), 286 fixup_layout(T0, T, State). 287 288fixup_element(E, E, []) :- 289 !. 290fixup_element(Fmt-Args, ansi(Ansi, Fmt, Args), Ansi) :- 291 !. 292fixup_element(E, E, _).

300join_blank_lines([nl(N)|T0], T, I0, I, Lines0, Lines) :- 301 !, 302 Lines1 is max(N, Lines0), 303 join_blank_lines(T0, T, I0, I, Lines1, Lines). 304join_blank_lines([indent(N)|T0], T, I0, I, Lines0, Lines) :- 305 !, 306 I1 is I0+N, 307 join_blank_lines(T0, T, I1, I, Lines0, Lines). 308join_blank_lines(L, L, I, I, Lines, Lines). 309 310indent(I, [Spaces|T], T) :- 311 I > 0, 312 !, 313 format(atom(Spaces), '~t~*|', [I]). 314indent(_, L, L). 315 316skip_lines(N, [nl|L0], L) :- 317 succ(N1, N), 318 !, 319 skip_lines(N1, L0, L). 320skip_lines(_, L, L)