jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2021-2022, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <LibWeb/Bindings/Intrinsics.h>
8#include <LibWeb/DOM/Document.h>
9#include <LibWeb/DOM/Range.h>
10#include <LibWeb/Selection/Selection.h>
11
12namespace Web::Selection {
13
14WebIDL::ExceptionOr<JS::NonnullGCPtr<Selection>> Selection::create(JS::NonnullGCPtr<JS::Realm> realm, JS::NonnullGCPtr<DOM::Document> document)
15{
16 return MUST_OR_THROW_OOM(realm->heap().allocate<Selection>(realm, realm, document));
17}
18
19Selection::Selection(JS::NonnullGCPtr<JS::Realm> realm, JS::NonnullGCPtr<DOM::Document> document)
20 : PlatformObject(realm)
21 , m_document(document)
22{
23}
24
25Selection::~Selection() = default;
26
27JS::ThrowCompletionOr<void> Selection::initialize(JS::Realm& realm)
28{
29 MUST_OR_THROW_OOM(Base::initialize(realm));
30 set_prototype(&Bindings::ensure_web_prototype<Bindings::SelectionPrototype>(realm, "Selection"));
31
32 return {};
33}
34
35// https://w3c.github.io/selection-api/#dfn-empty
36bool Selection::is_empty() const
37{
38 // Each selection can be associated with a single range.
39 // When there is no range associated with the selection, the selection is empty.
40 // The selection must be initially empty.
41
42 // NOTE: This function should not be confused with Selection.empty() which empties the selection.
43 return !m_range;
44}
45
46void Selection::visit_edges(Cell::Visitor& visitor)
47{
48 Base::visit_edges(visitor);
49 visitor.visit(m_range);
50 visitor.visit(m_document);
51}
52
53// https://w3c.github.io/selection-api/#dfn-anchor
54JS::GCPtr<DOM::Node> Selection::anchor_node()
55{
56 if (!m_range)
57 return nullptr;
58 if (m_direction == Direction::Forwards)
59 return m_range->start_container();
60 return m_range->end_container();
61}
62
63// https://w3c.github.io/selection-api/#dfn-anchor
64unsigned Selection::anchor_offset()
65{
66 if (!m_range)
67 return 0;
68 if (m_direction == Direction::Forwards)
69 return m_range->start_offset();
70 return m_range->end_offset();
71}
72
73// https://w3c.github.io/selection-api/#dfn-focus
74JS::GCPtr<DOM::Node> Selection::focus_node()
75{
76 if (!m_range)
77 return nullptr;
78 if (m_direction == Direction::Forwards)
79 return m_range->end_container();
80 return m_range->start_container();
81}
82
83// https://w3c.github.io/selection-api/#dfn-focus
84unsigned Selection::focus_offset() const
85{
86 if (!m_range)
87 return 0;
88 if (m_direction == Direction::Forwards)
89 return m_range->end_offset();
90 return m_range->start_offset();
91}
92
93// https://w3c.github.io/selection-api/#dom-selection-iscollapsed
94bool Selection::is_collapsed() const
95{
96 // The attribute must return true if and only if the anchor and focus are the same
97 // (including if both are null). Otherwise it must return false.
98 return const_cast<Selection*>(this)->anchor_node() == const_cast<Selection*>(this)->focus_node();
99}
100
101// https://w3c.github.io/selection-api/#dom-selection-rangecount
102unsigned Selection::range_count() const
103{
104 if (m_range)
105 return 1;
106 return 0;
107}
108
109DeprecatedString Selection::type() const
110{
111 if (!m_range)
112 return "None";
113 if (m_range->collapsed())
114 return "Caret";
115 return "Range";
116}
117
118// https://w3c.github.io/selection-api/#dom-selection-getrangeat
119WebIDL::ExceptionOr<JS::GCPtr<DOM::Range>> Selection::get_range_at(unsigned index)
120{
121 // The method must throw an IndexSizeError exception if index is not 0, or if this is empty.
122 if (index != 0 || is_empty())
123 return WebIDL::IndexSizeError::create(realm(), "Selection.getRangeAt() on empty Selection or with invalid argument"sv);
124
125 // Otherwise, it must return a reference to (not a copy of) this's range.
126 return m_range;
127}
128
129// https://w3c.github.io/selection-api/#dom-selection-addrange
130void Selection::add_range(JS::NonnullGCPtr<DOM::Range> range)
131{
132 // 1. If the root of the range's boundary points are not the document associated with this, abort these steps.
133 if (&range->start_container()->root() != m_document.ptr())
134 return;
135
136 // 2. If rangeCount is not 0, abort these steps.
137 if (range_count() != 0)
138 return;
139
140 // 3. Set this's range to range by a strong reference (not by making a copy).
141 set_range(range);
142}
143
144// https://w3c.github.io/selection-api/#dom-selection-removerange
145WebIDL::ExceptionOr<void> Selection::remove_range(JS::NonnullGCPtr<DOM::Range> range)
146{
147 // The method must make this empty by disassociating its range if this's range is range.
148 if (m_range == range) {
149 set_range(nullptr);
150 return {};
151 }
152
153 // Otherwise, it must throw a NotFoundError.
154 return WebIDL::NotFoundError::create(realm(), "Selection.removeRange() with invalid argument"sv);
155}
156
157// https://w3c.github.io/selection-api/#dom-selection-removeallranges
158void Selection::remove_all_ranges()
159{
160 // The method must make this empty by disassociating its range if this has an associated range.
161 set_range(nullptr);
162}
163
164// https://w3c.github.io/selection-api/#dom-selection-empty
165void Selection::empty()
166{
167 // The method must be an alias, and behave identically, to removeAllRanges().
168 remove_all_ranges();
169}
170
171// https://w3c.github.io/selection-api/#dom-selection-collapse
172WebIDL::ExceptionOr<void> Selection::collapse(JS::GCPtr<DOM::Node> node, unsigned offset)
173{
174 // 1. If node is null, this method must behave identically as removeAllRanges() and abort these steps.
175 if (!node) {
176 remove_all_ranges();
177 return {};
178 }
179
180 // 2. The method must throw an IndexSizeError exception if offset is longer than node's length and abort these steps.
181 if (offset > node->length()) {
182 return WebIDL::IndexSizeError::create(realm(), "Selection.collapse() with offset longer than node's length"sv);
183 }
184
185 // 3. If node's root is not the document associated with this, abort these steps.
186 if (&node->root() != m_document.ptr())
187 return {};
188
189 // 4. Otherwise, let newRange be a new range.
190 auto new_range = TRY(DOM::Range::create(*m_document));
191
192 // 5. Set the start the start and the end of newRange to (node, offset).
193 TRY(new_range->set_start(*node, offset));
194
195 // 6. Set this's range to newRange.
196 set_range(new_range);
197
198 return {};
199}
200
201// https://w3c.github.io/selection-api/#dom-selection-setposition
202WebIDL::ExceptionOr<void> Selection::set_position(JS::GCPtr<DOM::Node> node, unsigned offset)
203{
204 // The method must be an alias, and behave identically, to collapse().
205 return collapse(node, offset);
206}
207
208// https://w3c.github.io/selection-api/#dom-selection-collapsetostart
209WebIDL::ExceptionOr<void> Selection::collapse_to_start()
210{
211 // 1. The method must throw InvalidStateError exception if the this is empty.
212 if (!m_range) {
213 return WebIDL::InvalidStateError::create(realm(), "Selection.collapse_to_start() on empty range"sv);
214 }
215
216 // 2. Otherwise, it must create a new range
217 auto new_range = TRY(DOM::Range::create(*m_document));
218
219 // 3. Set the start both its start and end to the start of this's range
220 TRY(new_range->set_start(*anchor_node(), m_range->start_offset()));
221 TRY(new_range->set_end(*anchor_node(), m_range->start_offset()));
222
223 // 4. Then set this's range to the newly-created range.
224 set_range(new_range);
225 return {};
226}
227
228// https://w3c.github.io/selection-api/#dom-selection-collapsetoend
229WebIDL::ExceptionOr<void> Selection::collapse_to_end()
230{
231 // 1. The method must throw InvalidStateError exception if the this is empty.
232 if (!m_range) {
233 return WebIDL::InvalidStateError::create(realm(), "Selection.collapse_to_end() on empty range"sv);
234 }
235
236 // 2. Otherwise, it must create a new range
237 auto new_range = TRY(DOM::Range::create(*m_document));
238
239 // 3. Set the start both its start and end to the start of this's range
240 TRY(new_range->set_start(*anchor_node(), m_range->end_offset()));
241 TRY(new_range->set_end(*anchor_node(), m_range->end_offset()));
242
243 // 4. Then set this's range to the newly-created range.
244 set_range(new_range);
245
246 return {};
247}
248
249// https://w3c.github.io/selection-api/#dom-selection-extend
250WebIDL::ExceptionOr<void> Selection::extend(JS::NonnullGCPtr<DOM::Node> node, unsigned offset)
251{
252 // 1. If node's root is not the document associated with this, abort these steps.
253 if (&node->root() != m_document.ptr())
254 return {};
255
256 // 2. If this is empty, throw an InvalidStateError exception and abort these steps.
257 if (!m_range) {
258 return WebIDL::InvalidStateError::create(realm(), "Selection.extend() on empty range"sv);
259 }
260
261 // 3. Let oldAnchor and oldFocus be the this's anchor and focus, and let newFocus be the boundary point (node, offset).
262 auto& old_anchor_node = *anchor_node();
263 auto old_anchor_offset = anchor_offset();
264
265 auto& new_focus_node = node;
266 auto new_focus_offset = offset;
267
268 // 4. Let newRange be a new range.
269 auto new_range = TRY(DOM::Range::create(*m_document));
270
271 // 5. If node's root is not the same as the this's range's root, set the start newRange's start and end to newFocus.
272 if (&node->root() != &m_range->start_container()->root()) {
273 TRY(new_range->set_start(new_focus_node, new_focus_offset));
274 }
275 // 6. Otherwise, if oldAnchor is before or equal to newFocus, set the start newRange's start to oldAnchor, then set its end to newFocus.
276 else if (old_anchor_node.is_before(new_focus_node) || &old_anchor_node == new_focus_node.ptr()) {
277 TRY(new_range->set_end(new_focus_node, new_focus_offset));
278 }
279 // 7. Otherwise, set the start newRange's start to newFocus, then set its end to oldAnchor.
280 else {
281 TRY(new_range->set_start(new_focus_node, new_focus_offset));
282 TRY(new_range->set_end(old_anchor_node, old_anchor_offset));
283 }
284
285 // 8. Set this's range to newRange.
286 set_range(new_range);
287
288 // 9. If newFocus is before oldAnchor, set this's direction to backwards. Otherwise, set it to forwards.
289 if (new_focus_node->is_before(old_anchor_node)) {
290 m_direction = Direction::Backwards;
291 } else {
292 m_direction = Direction::Forwards;
293 }
294
295 return {};
296}
297
298// https://w3c.github.io/selection-api/#dom-selection-setbaseandextent
299WebIDL::ExceptionOr<void> Selection::set_base_and_extent(JS::NonnullGCPtr<DOM::Node> anchor_node, unsigned anchor_offset, JS::NonnullGCPtr<DOM::Node> focus_node, unsigned focus_offset)
300{
301 // 1. If anchorOffset is longer than anchorNode's length or if focusOffset is longer than focusNode's length, throw an IndexSizeError exception and abort these steps.
302 if (anchor_offset > anchor_node->length())
303 return WebIDL::IndexSizeError::create(realm(), "Anchor offset points outside of the anchor node");
304
305 if (focus_offset > focus_node->length())
306 return WebIDL::IndexSizeError::create(realm(), "Focus offset points outside of the focus node");
307
308 // 2. If the roots of anchorNode or focusNode are not the document associated with this, abort these steps.
309 if (&anchor_node->root() != m_document.ptr())
310 return {};
311
312 if (&focus_node->root() != m_document.ptr())
313 return {};
314
315 // 3. Let anchor be the boundary point (anchorNode, anchorOffset) and let focus be the boundary point (focusNode, focusOffset).
316
317 // 4. Let newRange be a new range.
318 auto new_range = TRY(DOM::Range::create(*m_document));
319
320 // 5. If anchor is before focus, set the start the newRange's start to anchor and its end to focus. Otherwise, set the start them to focus and anchor respectively.
321 auto position_of_anchor_relative_to_focus = DOM::position_of_boundary_point_relative_to_other_boundary_point(anchor_node, anchor_offset, focus_node, focus_offset);
322 if (position_of_anchor_relative_to_focus == DOM::RelativeBoundaryPointPosition::Before) {
323 TRY(new_range->set_start(anchor_node, anchor_offset));
324 TRY(new_range->set_end(focus_node, focus_offset));
325 } else {
326 TRY(new_range->set_start(focus_node, focus_offset));
327 TRY(new_range->set_end(anchor_node, anchor_offset));
328 }
329
330 // 6. Set this's range to newRange.
331 set_range(new_range);
332
333 // 7. If focus is before anchor, set this's direction to backwards. Otherwise, set it to forwards
334 // NOTE: "Otherwise" can be seen as "focus is equal to or after anchor".
335 if (position_of_anchor_relative_to_focus == DOM::RelativeBoundaryPointPosition::After)
336 m_direction = Direction::Backwards;
337 else
338 m_direction = Direction::Forwards;
339
340 return {};
341}
342
343// https://w3c.github.io/selection-api/#dom-selection-selectallchildren
344WebIDL::ExceptionOr<void> Selection::select_all_children(JS::NonnullGCPtr<DOM::Node> node)
345{
346 // 1. If node's root is not the document associated with this, abort these steps.
347 if (&node->root() != m_document.ptr())
348 return {};
349
350 // 2. Let newRange be a new range and childCount be the number of children of node.
351 auto new_range = TRY(DOM::Range::create(*m_document));
352 auto child_count = node->child_count();
353
354 // 3. Set newRange's start to (node, 0).
355 TRY(new_range->set_start(node, 0));
356
357 // 4. Set newRange's end to (node, childCount).
358 TRY(new_range->set_end(node, child_count));
359
360 // 5. Set this's range to newRange.
361 set_range(new_range);
362
363 // 6. Set this's direction to forwards.
364 m_direction = Direction::Forwards;
365
366 return {};
367}
368
369// https://w3c.github.io/selection-api/#dom-selection-deletefromdocument
370WebIDL::ExceptionOr<void> Selection::delete_from_document()
371{
372 // The method must invoke deleteContents() on this's range if this is not empty.
373 // Otherwise the method must do nothing.
374 if (!is_empty())
375 return m_range->delete_contents();
376 return {};
377}
378
379// https://w3c.github.io/selection-api/#dom-selection-containsnode
380bool Selection::contains_node(JS::NonnullGCPtr<DOM::Node> node, bool allow_partial_containment) const
381{
382 // The method must return false if this is empty or if node's root is not the document associated with this.
383 if (!m_range)
384 return false;
385 if (&node->root() != m_document.ptr())
386 return false;
387
388 // Otherwise, if allowPartialContainment is false, the method must return true if and only if
389 // start of its range is before or visually equivalent to the first boundary point in the node
390 // and end of its range is after or visually equivalent to the last boundary point in the node.
391 if (!allow_partial_containment) {
392 auto start_relative_position = DOM::position_of_boundary_point_relative_to_other_boundary_point(
393 *m_range->start_container(),
394 m_range->start_offset(),
395 node,
396 0);
397 auto end_relative_position = DOM::position_of_boundary_point_relative_to_other_boundary_point(
398 *m_range->end_container(),
399 m_range->end_offset(),
400 node,
401 node->length());
402
403 return (start_relative_position == DOM::RelativeBoundaryPointPosition::Before || start_relative_position == DOM::RelativeBoundaryPointPosition::Equal)
404 && (end_relative_position == DOM::RelativeBoundaryPointPosition::Equal || end_relative_position == DOM::RelativeBoundaryPointPosition::After);
405 }
406
407 // If allowPartialContainment is true, the method must return true if and only if
408 // start of its range is before or visually equivalent to the last boundary point in the node
409 // and end of its range is after or visually equivalent to the first boundary point in the node.
410
411 auto start_relative_position = DOM::position_of_boundary_point_relative_to_other_boundary_point(
412 *m_range->start_container(),
413 m_range->start_offset(),
414 node,
415 node->length());
416 auto end_relative_position = DOM::position_of_boundary_point_relative_to_other_boundary_point(
417 *m_range->end_container(),
418 m_range->end_offset(),
419 node,
420 0);
421
422 return (start_relative_position == DOM::RelativeBoundaryPointPosition::Before || start_relative_position == DOM::RelativeBoundaryPointPosition::Equal)
423 && (end_relative_position == DOM::RelativeBoundaryPointPosition::Equal || end_relative_position == DOM::RelativeBoundaryPointPosition::After);
424}
425
426DeprecatedString Selection::to_deprecated_string() const
427{
428 // FIXME: This needs more work to be compatible with other engines.
429 // See https://www.w3.org/Bugs/Public/show_bug.cgi?id=10583
430 if (!m_range)
431 return DeprecatedString::empty();
432 return m_range->to_deprecated_string();
433}
434
435JS::NonnullGCPtr<DOM::Document> Selection::document() const
436{
437 return m_document;
438}
439
440JS::GCPtr<DOM::Range> Selection::range() const
441{
442 return m_range;
443}
444
445void Selection::set_range(JS::GCPtr<DOM::Range> range)
446{
447 if (m_range == range)
448 return;
449
450 if (m_range)
451 m_range->set_associated_selection({}, nullptr);
452
453 m_range = range;
454
455 if (m_range)
456 m_range->set_associated_selection({}, this);
457}
458
459}