1/*
2 * Copyright (C) 2005, 2006 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "InsertParagraphSeparatorCommand.h"
28
29#include "Document.h"
30#include "Editing.h"
31#include "EditingStyle.h"
32#include "HTMLBRElement.h"
33#include "HTMLFormElement.h"
34#include "HTMLNames.h"
35#include "InsertLineBreakCommand.h"
36#include "NodeTraversal.h"
37#include "RenderText.h"
38#include "Text.h"
39#include "VisibleUnits.h"
40
41namespace WebCore {
42
43using namespace HTMLNames;
44
45// When inserting a new line, we want to avoid nesting empty divs if we can. Otherwise, when
46// pasting, it's easy to have each new line be a div deeper than the previous. E.g., in the case
47// below, we want to insert at ^ instead of |.
48// <div>foo<div>bar</div>|</div>^
49static Element* highestVisuallyEquivalentDivBelowRoot(Element* startBlock)
50{
51 Element* curBlock = startBlock;
52 // We don't want to return a root node (if it happens to be a div, e.g., in a document fragment) because there are no
53 // siblings for us to append to.
54 while (!curBlock->nextSibling() && curBlock->parentElement()->hasTagName(divTag) && curBlock->parentElement()->parentElement()) {
55 if (curBlock->parentElement()->hasAttributes())
56 break;
57 curBlock = curBlock->parentElement();
58 }
59 return curBlock;
60}
61
62InsertParagraphSeparatorCommand::InsertParagraphSeparatorCommand(Document& document, bool mustUseDefaultParagraphElement, bool pasteBlockqutoeIntoUnquotedArea, EditAction editingAction)
63 : CompositeEditCommand(document, editingAction)
64 , m_mustUseDefaultParagraphElement(mustUseDefaultParagraphElement)
65 , m_pasteBlockqutoeIntoUnquotedArea(pasteBlockqutoeIntoUnquotedArea)
66{
67}
68
69bool InsertParagraphSeparatorCommand::preservesTypingStyle() const
70{
71 return true;
72}
73
74void InsertParagraphSeparatorCommand::calculateStyleBeforeInsertion(const Position &pos)
75{
76 // It is only important to set a style to apply later if we're at the boundaries of
77 // a paragraph. Otherwise, content that is moved as part of the work of the command
78 // will lend their styles to the new paragraph without any extra work needed.
79 VisiblePosition visiblePos(pos, VP_DEFAULT_AFFINITY);
80 if (!isStartOfParagraph(visiblePos) && !isEndOfParagraph(visiblePos))
81 return;
82
83 ASSERT(pos.isNotNull());
84 m_style = EditingStyle::create(pos, EditingStyle::EditingPropertiesInEffect);
85 m_style->mergeTypingStyle(pos.anchorNode()->document());
86}
87
88void InsertParagraphSeparatorCommand::applyStyleAfterInsertion(Node* originalEnclosingBlock)
89{
90 // Not only do we break out of header tags, but we also do not preserve the typing style,
91 // in order to match other browsers.
92 if (originalEnclosingBlock->hasTagName(h1Tag) ||
93 originalEnclosingBlock->hasTagName(h2Tag) ||
94 originalEnclosingBlock->hasTagName(h3Tag) ||
95 originalEnclosingBlock->hasTagName(h4Tag) ||
96 originalEnclosingBlock->hasTagName(h5Tag))
97 return;
98
99 if (!m_style)
100 return;
101
102 m_style->prepareToApplyAt(endingSelection().start());
103 if (!m_style->isEmpty())
104 applyStyle(m_style.get());
105}
106
107bool InsertParagraphSeparatorCommand::shouldUseDefaultParagraphElement(Node* enclosingBlock) const
108{
109 if (m_mustUseDefaultParagraphElement)
110 return true;
111
112 // Assumes that if there was a range selection, it was already deleted.
113 if (!isEndOfBlock(endingSelection().visibleStart()))
114 return false;
115
116 return enclosingBlock->hasTagName(h1Tag) ||
117 enclosingBlock->hasTagName(h2Tag) ||
118 enclosingBlock->hasTagName(h3Tag) ||
119 enclosingBlock->hasTagName(h4Tag) ||
120 enclosingBlock->hasTagName(h5Tag);
121}
122
123void InsertParagraphSeparatorCommand::getAncestorsInsideBlock(const Node* insertionNode, Element* outerBlock, Vector<RefPtr<Element>>& ancestors)
124{
125 ancestors.clear();
126
127 // Build up list of ancestors elements between the insertion node and the outer block.
128 if (insertionNode != outerBlock) {
129 for (Element* n = insertionNode->parentElement(); n && n != outerBlock; n = n->parentElement())
130 ancestors.append(n);
131 }
132}
133
134Ref<Element> InsertParagraphSeparatorCommand::cloneHierarchyUnderNewBlock(const Vector<RefPtr<Element>>& ancestors, Ref<Element>&& blockToInsert)
135{
136 // Make clones of ancestors in between the start node and the start block.
137 RefPtr<Element> parent = WTFMove(blockToInsert);
138 for (size_t i = ancestors.size(); i != 0; --i) {
139 auto child = ancestors[i - 1]->cloneElementWithoutChildren(document());
140 // It should always be okay to remove id from the cloned elements, since the originals are not deleted.
141 child->removeAttribute(idAttr);
142 appendNode(child.copyRef(), parent.releaseNonNull());
143 parent = WTFMove(child);
144 }
145
146 return parent.releaseNonNull();
147}
148
149void InsertParagraphSeparatorCommand::doApply()
150{
151 if (endingSelection().isNoneOrOrphaned())
152 return;
153
154 Position insertionPosition = endingSelection().start();
155
156 EAffinity affinity = endingSelection().affinity();
157
158 // Delete the current selection.
159 if (endingSelection().isRange()) {
160 calculateStyleBeforeInsertion(insertionPosition);
161 deleteSelection(false, true);
162 insertionPosition = endingSelection().start();
163 affinity = endingSelection().affinity();
164 }
165
166 // FIXME: The parentAnchoredEquivalent conversion needs to be moved into enclosingBlock.
167 RefPtr<Element> startBlock = enclosingBlock(insertionPosition.parentAnchoredEquivalent().containerNode());
168 Position canonicalPos = VisiblePosition(insertionPosition).deepEquivalent();
169 if (!startBlock
170 || !startBlock->nonShadowBoundaryParentNode()
171 || isTableCell(startBlock.get())
172 || is<HTMLFormElement>(*startBlock)
173 // FIXME: If the node is hidden, we don't have a canonical position so we will do the wrong thing for tables and <hr>. https://bugs.webkit.org/show_bug.cgi?id=40342
174 || (!canonicalPos.isNull() && canonicalPos.deprecatedNode()->renderer() && canonicalPos.deprecatedNode()->renderer()->isTable())
175 || (!canonicalPos.isNull() && canonicalPos.deprecatedNode()->hasTagName(hrTag))) {
176 applyCommandToComposite(InsertLineBreakCommand::create(document()));
177 return;
178 }
179
180 // Use the leftmost candidate.
181 insertionPosition = insertionPosition.upstream();
182 if (!insertionPosition.isCandidate())
183 insertionPosition = insertionPosition.downstream();
184
185 // Adjust the insertion position after the delete
186 insertionPosition = positionAvoidingSpecialElementBoundary(insertionPosition);
187 VisiblePosition visiblePos(insertionPosition, affinity);
188 if (visiblePos.isNull())
189 return;
190
191 calculateStyleBeforeInsertion(insertionPosition);
192
193 //---------------------------------------------------------------------
194 // Handle special case of typing return on an empty list item
195 if (breakOutOfEmptyListItem())
196 return;
197
198 //---------------------------------------------------------------------
199 // Prepare for more general cases.
200
201 bool isFirstInBlock = isStartOfBlock(visiblePos);
202 bool isLastInBlock = isEndOfBlock(visiblePos);
203 bool nestNewBlock = false;
204
205 // Create block to be inserted.
206 RefPtr<Element> blockToInsert;
207 if (startBlock->isRootEditableElement()) {
208 blockToInsert = createDefaultParagraphElement(document());
209 nestNewBlock = true;
210 } else if (shouldUseDefaultParagraphElement(startBlock.get()))
211 blockToInsert = createDefaultParagraphElement(document());
212 else
213 blockToInsert = startBlock->cloneElementWithoutChildren(document());
214
215 //---------------------------------------------------------------------
216 // Handle case when position is in the last visible position in its block,
217 // including when the block is empty.
218 if (isLastInBlock) {
219 if (nestNewBlock) {
220 if (isFirstInBlock && !lineBreakExistsAtVisiblePosition(visiblePos)) {
221 // The block is empty. Create an empty block to
222 // represent the paragraph that we're leaving.
223 auto extraBlock = createDefaultParagraphElement(document());
224 appendNode(extraBlock.copyRef(), *startBlock);
225 appendBlockPlaceholder(WTFMove(extraBlock));
226 }
227 appendNode(*blockToInsert, *startBlock);
228 } else {
229 // We can get here if we pasted a copied portion of a blockquote with a newline at the end and are trying to paste it
230 // into an unquoted area. We then don't want the newline within the blockquote or else it will also be quoted.
231 if (m_pasteBlockqutoeIntoUnquotedArea) {
232 if (Node* highestBlockquote = highestEnclosingNodeOfType(canonicalPos, &isMailBlockquote))
233 startBlock = downcast<Element>(highestBlockquote);
234 }
235
236 // Most of the time we want to stay at the nesting level of the startBlock (e.g., when nesting within lists). However,
237 // for div nodes, this can result in nested div tags that are hard to break out of.
238 Element* siblingNode = startBlock.get();
239 if (blockToInsert->hasTagName(divTag))
240 siblingNode = highestVisuallyEquivalentDivBelowRoot(startBlock.get());
241 insertNodeAfter(*blockToInsert, *siblingNode);
242 }
243
244 // Recreate the same structure in the new paragraph.
245
246 Vector<RefPtr<Element>> ancestors;
247 getAncestorsInsideBlock(positionOutsideTabSpan(insertionPosition).deprecatedNode(), startBlock.get(), ancestors);
248 auto parent = cloneHierarchyUnderNewBlock(ancestors, *blockToInsert);
249 auto* parentPtr = parent.ptr();
250
251 appendBlockPlaceholder(WTFMove(parent));
252
253 setEndingSelection(VisibleSelection(firstPositionInNode(parentPtr), DOWNSTREAM, endingSelection().isDirectional()));
254 return;
255 }
256
257
258 //---------------------------------------------------------------------
259 // Handle case when position is in the first visible position in its block, and
260 // similar case where previous position is in another, presumeably nested, block.
261 if (isFirstInBlock || !inSameBlock(visiblePos, visiblePos.previous())) {
262 Node *refNode;
263
264 insertionPosition = positionOutsideTabSpan(insertionPosition);
265
266 if (isFirstInBlock && !nestNewBlock)
267 refNode = startBlock.get();
268 else if (isFirstInBlock && nestNewBlock) {
269 // startBlock should always have children, otherwise isLastInBlock would be true and it's handled above.
270 ASSERT(startBlock->firstChild());
271 refNode = startBlock->firstChild();
272 } else if (insertionPosition.containerNode() == startBlock && nestNewBlock) {
273 refNode = startBlock->traverseToChildAt(insertionPosition.computeOffsetInContainerNode());
274 ASSERT(refNode); // must be true or we'd be in the end of block case
275 } else
276 refNode = insertionPosition.deprecatedNode();
277
278 // find ending selection position easily before inserting the paragraph
279 insertionPosition = insertionPosition.downstream();
280
281 insertNodeBefore(*blockToInsert, *refNode);
282
283 // Recreate the same structure in the new paragraph.
284
285 Vector<RefPtr<Element>> ancestors;
286 getAncestorsInsideBlock(positionAvoidingSpecialElementBoundary(positionOutsideTabSpan(insertionPosition)).deprecatedNode(), startBlock.get(), ancestors);
287
288 appendBlockPlaceholder(cloneHierarchyUnderNewBlock(ancestors, *blockToInsert));
289
290 // In this case, we need to set the new ending selection.
291 setEndingSelection(VisibleSelection(insertionPosition, DOWNSTREAM, endingSelection().isDirectional()));
292 return;
293 }
294
295 //---------------------------------------------------------------------
296 // Handle the (more complicated) general case,
297
298 // All of the content in the current block after visiblePos is
299 // about to be wrapped in a new paragraph element. Add a br before
300 // it if visiblePos is at the start of a paragraph so that the
301 // content will move down a line.
302 if (isStartOfParagraph(visiblePos)) {
303 auto br = HTMLBRElement::create(document());
304 auto* brPtr = br.ptr();
305 insertNodeAt(WTFMove(br), insertionPosition);
306 insertionPosition = positionInParentAfterNode(brPtr);
307 // If the insertion point is a break element, there is nothing else
308 // we need to do.
309 if (visiblePos.deepEquivalent().anchorNode()->renderer()->isBR()) {
310 setEndingSelection(VisibleSelection(insertionPosition, DOWNSTREAM, endingSelection().isDirectional()));
311 return;
312 }
313 }
314
315 // Move downstream. Typing style code will take care of carrying along the
316 // style of the upstream position.
317 insertionPosition = insertionPosition.downstream();
318
319 // At this point, the insertionPosition's node could be a container, and we want to make sure we include
320 // all of the correct nodes when building the ancestor list. So this needs to be the deepest representation of the position
321 // before we walk the DOM tree.
322 insertionPosition = positionOutsideTabSpan(VisiblePosition(insertionPosition).deepEquivalent());
323
324 // If the returned position lies either at the end or at the start of an element that is ignored by editing
325 // we should move to its upstream or downstream position.
326 if (editingIgnoresContent(*insertionPosition.deprecatedNode())) {
327 if (insertionPosition.atLastEditingPositionForNode())
328 insertionPosition = insertionPosition.downstream();
329 else if (insertionPosition.atFirstEditingPositionForNode())
330 insertionPosition = insertionPosition.upstream();
331 }
332
333 // Make sure we do not cause a rendered space to become unrendered.
334 // FIXME: We need the affinity for pos, but pos.downstream() does not give it
335 Position leadingWhitespace = insertionPosition.leadingWhitespacePosition(VP_DEFAULT_AFFINITY);
336 // FIXME: leadingWhitespacePosition is returning the position before preserved newlines for positions
337 // after the preserved newline, causing the newline to be turned into a nbsp.
338 if (is<Text>(leadingWhitespace.deprecatedNode())) {
339 Text& textNode = downcast<Text>(*leadingWhitespace.deprecatedNode());
340 ASSERT(!textNode.renderer() || textNode.renderer()->style().collapseWhiteSpace());
341 replaceTextInNodePreservingMarkers(textNode, leadingWhitespace.deprecatedEditingOffset(), 1, nonBreakingSpaceString());
342 }
343
344 // Split at pos if in the middle of a text node.
345 Position positionAfterSplit;
346 if (insertionPosition.anchorType() == Position::PositionIsOffsetInAnchor && is<Text>(*insertionPosition.containerNode())) {
347 Ref<Text> textNode = downcast<Text>(*insertionPosition.containerNode());
348 bool atEnd = static_cast<unsigned>(insertionPosition.offsetInContainerNode()) >= textNode->length();
349 if (insertionPosition.deprecatedEditingOffset() > 0 && !atEnd) {
350 splitTextNode(textNode, insertionPosition.offsetInContainerNode());
351 positionAfterSplit = firstPositionInNode(textNode.ptr());
352 if (!textNode->previousSibling())
353 return; // Bail out if mutation events detachd the split text node.
354 insertionPosition.moveToPosition(textNode->previousSibling(), insertionPosition.offsetInContainerNode());
355 visiblePos = VisiblePosition(insertionPosition);
356 }
357 }
358
359 // If we got detached due to mutation events, just bail out.
360 if (!startBlock->parentNode())
361 return;
362
363 // Put the added block in the tree.
364 if (nestNewBlock)
365 appendNode(*blockToInsert, *startBlock);
366 else
367 insertNodeAfter(*blockToInsert, *startBlock);
368
369 document().updateLayoutIgnorePendingStylesheets();
370
371 // If the paragraph separator was inserted at the end of a paragraph, an empty line must be
372 // created. All of the nodes, starting at visiblePos, are about to be added to the new paragraph
373 // element. If the first node to be inserted won't be one that will hold an empty line open, add a br.
374 if (isEndOfParagraph(visiblePos) && !lineBreakExistsAtVisiblePosition(visiblePos))
375 appendNode(HTMLBRElement::create(document()), *blockToInsert);
376
377 // Move the start node and the siblings of the start node.
378 if (VisiblePosition(insertionPosition) != VisiblePosition(positionBeforeNode(blockToInsert.get()))) {
379 Node* n;
380 if (insertionPosition.containerNode() == startBlock)
381 n = insertionPosition.computeNodeAfterPosition();
382 else {
383 Node* splitTo = insertionPosition.containerNode();
384 if (is<Text>(*splitTo) && insertionPosition.offsetInContainerNode() >= caretMaxOffset(*splitTo))
385 splitTo = NodeTraversal::next(*splitTo, startBlock.get());
386 ASSERT(splitTo);
387 splitTreeToNode(*splitTo, *startBlock);
388
389 for (n = startBlock->firstChild(); n; n = n->nextSibling()) {
390 VisiblePosition beforeNodePosition = positionBeforeNode(n);
391 if (!beforeNodePosition.isNull() && comparePositions(VisiblePosition(insertionPosition), beforeNodePosition) <= 0)
392 break;
393 }
394 }
395
396 moveRemainingSiblingsToNewParent(n, blockToInsert.get(), *blockToInsert);
397 }
398
399 // Handle whitespace that occurs after the split
400 if (positionAfterSplit.isNotNull()) {
401 document().updateLayoutIgnorePendingStylesheets();
402 if (!positionAfterSplit.isRenderedCharacter()) {
403 // Clear out all whitespace and insert one non-breaking space
404 ASSERT(!positionAfterSplit.containerNode()->renderer() || positionAfterSplit.containerNode()->renderer()->style().collapseWhiteSpace());
405 deleteInsignificantTextDownstream(positionAfterSplit);
406 if (is<Text>(*positionAfterSplit.deprecatedNode()))
407 insertTextIntoNode(downcast<Text>(*positionAfterSplit.containerNode()), 0, nonBreakingSpaceString());
408 }
409 }
410
411 setEndingSelection(VisibleSelection(firstPositionInNode(blockToInsert.get()), DOWNSTREAM, endingSelection().isDirectional()));
412 applyStyleAfterInsertion(startBlock.get());
413}
414
415} // namespace WebCore
416