1 /*
2  * Copyright (C) 2005 Apple Computer, 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 COMPUTER, 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 COMPUTER, 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 "InsertTextCommand.h"
28 
29 #include "Document.h"
30 #include "Element.h"
31 #include "EditingText.h"
32 #include "Editor.h"
33 #include "Frame.h"
34 #include "HTMLInterchange.h"
35 #include "htmlediting.h"
36 #include "visible_units.h"
37 #include <wtf/unicode/CharacterNames.h>
38 
39 namespace WebCore {
40 
InsertTextCommand(Document * document)41 InsertTextCommand::InsertTextCommand(Document *document)
42     : CompositeEditCommand(document)
43 {
44 }
45 
doApply()46 void InsertTextCommand::doApply()
47 {
48 }
49 
positionInsideTextNode(const Position & p)50 Position InsertTextCommand::positionInsideTextNode(const Position& p)
51 {
52     Position pos = p;
53     if (isTabSpanTextNode(pos.anchorNode())) {
54         RefPtr<Node> textNode = document()->createEditingTextNode("");
55         insertNodeAtTabSpanPosition(textNode.get(), pos);
56         return firstPositionInNode(textNode.get());
57     }
58 
59     // Prepare for text input by looking at the specified position.
60     // It may be necessary to insert a text node to receive characters.
61     if (!pos.containerNode()->isTextNode()) {
62         RefPtr<Node> textNode = document()->createEditingTextNode("");
63         insertNodeAt(textNode.get(), pos);
64         return firstPositionInNode(textNode.get());
65     }
66 
67     return pos;
68 }
69 
70 // This avoids the expense of a full fledged delete operation, and avoids a layout that typically results
71 // from text removal.
performTrivialReplace(const String & text,bool selectInsertedText)72 bool InsertTextCommand::performTrivialReplace(const String& text, bool selectInsertedText)
73 {
74     if (!endingSelection().isRange())
75         return false;
76 
77     if (text.contains('\t') || text.contains(' ') || text.contains('\n'))
78         return false;
79 
80     Position start = endingSelection().start().parentAnchoredEquivalent();
81     Position end = endingSelection().end().parentAnchoredEquivalent();
82     ASSERT(start.anchorType() == Position::PositionIsOffsetInAnchor);
83     ASSERT(end.anchorType() == Position::PositionIsOffsetInAnchor);
84 
85     if (start.containerNode() != end.containerNode() || !start.containerNode()->isTextNode() || isTabSpanTextNode(start.containerNode()))
86         return false;
87 
88     replaceTextInNode(static_cast<Text*>(start.containerNode()), start.offsetInContainerNode(), end.offsetInContainerNode() - start.offsetInContainerNode(), text);
89 
90     Position endPosition(start.containerNode(), start.offsetInContainerNode() + text.length());
91 
92     // We could have inserted a part of composed character sequence,
93     // so we are basically treating ending selection as a range to avoid validation.
94     // <http://bugs.webkit.org/show_bug.cgi?id=15781>
95     VisibleSelection forcedEndingSelection;
96     forcedEndingSelection.setWithoutValidation(start, endPosition);
97     setEndingSelection(forcedEndingSelection);
98 
99     if (!selectInsertedText)
100         setEndingSelection(VisibleSelection(endingSelection().visibleEnd()));
101 
102     return true;
103 }
104 
input(const String & text,bool selectInsertedText,RebalanceType whitespaceRebalance)105 void InsertTextCommand::input(const String& text, bool selectInsertedText, RebalanceType whitespaceRebalance)
106 {
107 
108     ASSERT(text.find('\n') == notFound);
109 
110     if (!endingSelection().isNonOrphanedCaretOrRange())
111         return;
112 
113     // Delete the current selection.
114     // FIXME: This delete operation blows away the typing style.
115     if (endingSelection().isRange()) {
116         if (performTrivialReplace(text, selectInsertedText))
117             return;
118         deleteSelection(false, true, true, false);
119     }
120 
121     Position startPosition(endingSelection().start());
122 
123     Position placeholder;
124     // We want to remove preserved newlines and brs that will collapse (and thus become unnecessary) when content
125     // is inserted just before them.
126     // FIXME: We shouldn't really have to do this, but removing placeholders is a workaround for 9661.
127     // If the caret is just before a placeholder, downstream will normalize the caret to it.
128     Position downstream(startPosition.downstream());
129     if (lineBreakExistsAtPosition(downstream)) {
130         // FIXME: This doesn't handle placeholders at the end of anonymous blocks.
131         VisiblePosition caret(startPosition);
132         if (isEndOfBlock(caret) && isStartOfParagraph(caret))
133             placeholder = downstream;
134         // Don't remove the placeholder yet, otherwise the block we're inserting into would collapse before
135         // we get a chance to insert into it.  We check for a placeholder now, though, because doing so requires
136         // the creation of a VisiblePosition, and if we did that post-insertion it would force a layout.
137     }
138 
139     // Insert the character at the leftmost candidate.
140     startPosition = startPosition.upstream();
141 
142     // It is possible for the node that contains startPosition to contain only unrendered whitespace,
143     // and so deleteInsignificantText could remove it.  Save the position before the node in case that happens.
144     Position positionBeforeStartNode(positionInParentBeforeNode(startPosition.containerNode()));
145     deleteInsignificantText(startPosition.upstream(), startPosition.downstream());
146     if (!startPosition.anchorNode()->inDocument())
147         startPosition = positionBeforeStartNode;
148     if (!startPosition.isCandidate())
149         startPosition = startPosition.downstream();
150 
151     startPosition = positionAvoidingSpecialElementBoundary(startPosition);
152 
153     Position endPosition;
154 
155     if (text == "\t") {
156         endPosition = insertTab(startPosition);
157         startPosition = endPosition.previous();
158         if (placeholder.isNotNull())
159             removePlaceholderAt(placeholder);
160     } else {
161         // Make sure the document is set up to receive text
162         startPosition = positionInsideTextNode(startPosition);
163         ASSERT(startPosition.anchorType() == Position::PositionIsOffsetInAnchor);
164         ASSERT(startPosition.containerNode());
165         ASSERT(startPosition.containerNode()->isTextNode());
166         if (placeholder.isNotNull())
167             removePlaceholderAt(placeholder);
168         Text* textNode = static_cast<Text*>(startPosition.containerNode());
169         const unsigned offset = startPosition.offsetInContainerNode();
170 
171         insertTextIntoNode(textNode, offset, text);
172         endPosition = Position(textNode, offset + text.length(), Position::PositionIsOffsetInAnchor);
173 
174         if (whitespaceRebalance == RebalanceLeadingAndTrailingWhitespaces) {
175             // The insertion may require adjusting adjacent whitespace, if it is present.
176             rebalanceWhitespaceAt(endPosition);
177             // Rebalancing on both sides isn't necessary if we've inserted only spaces.
178             if (!shouldRebalanceLeadingWhitespaceFor(text))
179                 rebalanceWhitespaceAt(startPosition);
180         } else {
181             ASSERT(whitespaceRebalance == RebalanceAllWhitespaces);
182             if (canRebalance(startPosition) && canRebalance(endPosition))
183                 rebalanceWhitespaceOnTextSubstring(textNode, startPosition.offsetInContainerNode(), endPosition.offsetInContainerNode());
184         }
185     }
186 
187     // We could have inserted a part of composed character sequence,
188     // so we are basically treating ending selection as a range to avoid validation.
189     // <http://bugs.webkit.org/show_bug.cgi?id=15781>
190     VisibleSelection forcedEndingSelection;
191     forcedEndingSelection.setWithoutValidation(startPosition, endPosition);
192     setEndingSelection(forcedEndingSelection);
193 
194     // Handle the case where there is a typing style.
195     if (RefPtr<EditingStyle> typingStyle = document()->frame()->selection()->typingStyle()) {
196         typingStyle->prepareToApplyAt(endPosition, EditingStyle::PreserveWritingDirection);
197         if (!typingStyle->isEmpty())
198             applyStyle(typingStyle.get());
199     }
200 
201     if (!selectInsertedText)
202         setEndingSelection(VisibleSelection(endingSelection().end(), endingSelection().affinity()));
203 }
204 
insertTab(const Position & pos)205 Position InsertTextCommand::insertTab(const Position& pos)
206 {
207     Position insertPos = VisiblePosition(pos, DOWNSTREAM).deepEquivalent();
208 
209     Node* node = insertPos.deprecatedNode();
210     unsigned int offset = insertPos.deprecatedEditingOffset();
211 
212     // keep tabs coalesced in tab span
213     if (isTabSpanTextNode(node)) {
214         insertTextIntoNode(static_cast<Text *>(node), offset, "\t");
215         return Position(node, offset + 1, Position::PositionIsOffsetInAnchor);
216     }
217 
218     // create new tab span
219     RefPtr<Element> spanNode = createTabSpanElement(document());
220 
221     // place it
222     if (!node->isTextNode()) {
223         insertNodeAt(spanNode.get(), insertPos);
224     } else {
225         Text *textNode = static_cast<Text *>(node);
226         if (offset >= textNode->length()) {
227             insertNodeAfter(spanNode.get(), textNode);
228         } else {
229             // split node to make room for the span
230             // NOTE: splitTextNode uses textNode for the
231             // second node in the split, so we need to
232             // insert the span before it.
233             if (offset > 0)
234                 splitTextNode(textNode, offset);
235             insertNodeBefore(spanNode, textNode);
236         }
237     }
238 
239     // return the position following the new tab
240     return lastPositionInNode(spanNode.get());
241 }
242 
isInsertTextCommand() const243 bool InsertTextCommand::isInsertTextCommand() const
244 {
245     return true;
246 }
247 
248 }
249