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29 #include "core/dom/ContainerNode.h"
30 #include "core/editing/EditingBoundary.h"
31 #include "core/editing/TextAffinity.h"
32 #include "platform/text/TextDirection.h"
33 #include "wtf/Assertions.h"
34 #include "wtf/PassRefPtr.h"
35 #include "wtf/RefPtr.h"
39 class CSSComputedStyleDeclaration;
47 enum PositionMoveType {
48 CodePoint, // Move by a single code point.
49 Character, // Move to the next Unicode character break.
50 BackwardDeletion // Subject to platform conventions.
56 PositionIsOffsetInAnchor,
57 PositionIsBeforeAnchor,
58 PositionIsAfterAnchor,
59 PositionIsBeforeChildren,
60 PositionIsAfterChildren,
65 , m_anchorType(PositionIsOffsetInAnchor)
66 , m_isLegacyEditingPosition(false)
70 // For creating legacy editing positions: (Anchor type will be determined from editingIgnoresContent(node))
71 class LegacyEditingOffset {
73 int value() const { return m_offset; }
76 explicit LegacyEditingOffset(int offset) : m_offset(offset) { }
78 friend Position createLegacyEditingPosition(PassRefPtr<Node>, int offset);
82 Position(PassRefPtr<Node> anchorNode, LegacyEditingOffset);
84 // For creating before/after positions:
85 Position(PassRefPtr<Node> anchorNode, AnchorType);
86 Position(PassRefPtr<Text> textNode, unsigned offset);
88 // For creating offset positions:
89 // FIXME: This constructor should eventually go away. See bug 63040.
90 Position(PassRefPtr<Node> anchorNode, int offset, AnchorType);
92 AnchorType anchorType() const { return static_cast<AnchorType>(m_anchorType); }
94 void clear() { m_anchorNode.clear(); m_offset = 0; m_anchorType = PositionIsOffsetInAnchor; m_isLegacyEditingPosition = false; }
96 // These are always DOM compliant values. Editing positions like [img, 0] (aka [img, before])
97 // will return img->parentNode() and img->nodeIndex() from these functions.
98 Node* containerNode() const; // NULL for a before/after position anchored to a node with no parent
99 Text* containerText() const;
101 int computeOffsetInContainerNode() const; // O(n) for before/after-anchored positions, O(1) for parent-anchored positions
102 Position parentAnchoredEquivalent() const; // Convenience method for DOM positions that also fixes up some positions for editing
104 // Inline O(1) access for Positions which callers know to be parent-anchored
105 int offsetInContainerNode() const
107 ASSERT(anchorType() == PositionIsOffsetInAnchor);
111 // New code should not use this function.
112 int deprecatedEditingOffset() const
114 if (m_isLegacyEditingPosition || (m_anchorType != PositionIsAfterAnchor && m_anchorType != PositionIsAfterChildren))
116 return offsetForPositionAfterAnchor();
119 // These are convenience methods which are smart about whether the position is neighbor anchored or parent anchored
120 Node* computeNodeBeforePosition() const;
121 Node* computeNodeAfterPosition() const;
123 Node* anchorNode() const { return m_anchorNode.get(); }
125 // FIXME: Callers should be moved off of node(), node() is not always the container for this position.
126 // For nodes which editingIgnoresContent(node()) returns true, positions like [ignoredNode, 0]
127 // will be treated as before ignoredNode (thus node() is really after the position, not containing it).
128 Node* deprecatedNode() const { return m_anchorNode.get(); }
130 Document* document() const { return m_anchorNode ? &m_anchorNode->document() : 0; }
131 bool inDocument() const { return m_anchorNode && m_anchorNode->inDocument(); }
132 Element* rootEditableElement() const
134 Node* container = containerNode();
135 return container ? container->rootEditableElement() : 0;
138 // These should only be used for PositionIsOffsetInAnchor positions, unless
139 // the position is a legacy editing position.
140 void moveToPosition(PassRefPtr<Node> anchorNode, int offset);
141 void moveToOffset(int offset);
143 bool isNull() const { return !m_anchorNode; }
144 bool isNotNull() const { return m_anchorNode; }
145 bool isOrphan() const { return m_anchorNode && !m_anchorNode->inDocument(); }
147 Element* element() const;
148 PassRefPtrWillBeRawPtr<CSSComputedStyleDeclaration> computedStyle() const;
150 // Move up or down the DOM by one position.
151 // Offsets are computed using render text for nodes that have renderers - but note that even when
152 // using composed characters, the result may be inside a single user-visible character if a ligature is formed.
153 Position previous(PositionMoveType = CodePoint) const;
154 Position next(PositionMoveType = CodePoint) const;
155 static int uncheckedPreviousOffset(const Node*, int current);
156 static int uncheckedPreviousOffsetForBackwardDeletion(const Node*, int current);
157 static int uncheckedNextOffset(const Node*, int current);
159 // These can be either inside or just before/after the node, depending on
160 // if the node is ignored by editing or not.
161 // FIXME: These should go away. They only make sense for legacy positions.
162 bool atFirstEditingPositionForNode() const;
163 bool atLastEditingPositionForNode() const;
165 // Returns true if the visually equivalent positions around have different editability
166 bool atEditingBoundary() const;
167 Node* parentEditingBoundary() const;
169 bool atStartOfTree() const;
170 bool atEndOfTree() const;
172 // FIXME: Make these non-member functions and put them somewhere in the editing directory.
173 // These aren't really basic "position" operations. More high level editing helper functions.
174 Position leadingWhitespacePosition(EAffinity, bool considerNonCollapsibleWhitespace = false) const;
175 Position trailingWhitespacePosition(EAffinity, bool considerNonCollapsibleWhitespace = false) const;
177 // These return useful visually equivalent positions.
178 Position upstream(EditingBoundaryCrossingRule = CannotCrossEditingBoundary) const;
179 Position downstream(EditingBoundaryCrossingRule = CannotCrossEditingBoundary) const;
181 bool isCandidate() const;
182 bool inRenderedText() const;
183 bool isRenderedCharacter() const;
184 bool rendersInDifferentPosition(const Position&) const;
186 void getInlineBoxAndOffset(EAffinity, InlineBox*&, int& caretOffset) const;
187 void getInlineBoxAndOffset(EAffinity, TextDirection primaryDirection, InlineBox*&, int& caretOffset) const;
189 TextDirection primaryDirection() const;
191 static bool hasRenderedNonAnonymousDescendantsWithHeight(RenderObject*);
192 static bool nodeIsUserSelectNone(Node*);
193 static bool nodeIsUserSelectAll(const Node*);
194 static Node* rootUserSelectAllForNode(Node*);
196 static ContainerNode* findParent(const Node*);
198 void debugPosition(const char* msg = "") const;
201 void formatForDebugger(char* buffer, unsigned length) const;
202 void showAnchorTypeAndOffset() const;
203 void showTreeForThis() const;
207 int offsetForPositionAfterAnchor() const;
209 int renderedOffset() const;
211 Position previousCharacterPosition(EAffinity) const;
213 static AnchorType anchorTypeForLegacyEditingPosition(Node* anchorNode, int offset);
215 RefPtr<Node> m_anchorNode;
216 // m_offset can be the offset inside m_anchorNode, or if editingIgnoresContent(m_anchorNode)
217 // returns true, then other places in editing will treat m_offset == 0 as "before the anchor"
218 // and m_offset > 0 as "after the anchor node". See parentAnchoredEquivalent for more info.
220 unsigned m_anchorType : 3;
221 bool m_isLegacyEditingPosition : 1;
224 inline Position createLegacyEditingPosition(PassRefPtr<Node> node, int offset)
226 return Position(node, Position::LegacyEditingOffset(offset));
229 inline bool operator==(const Position& a, const Position& b)
231 // FIXME: In <div><img></div> [div, 0] != [img, 0] even though most of the
232 // editing code will treat them as identical.
233 return a.anchorNode() == b.anchorNode() && a.deprecatedEditingOffset() == b.deprecatedEditingOffset() && a.anchorType() == b.anchorType();
236 inline bool operator!=(const Position& a, const Position& b)
241 // We define position creation functions to make callsites more readable.
242 // These are inline to prevent ref-churn when returning a Position object.
243 // If we ever add a PassPosition we can make these non-inline.
245 inline Position positionInParentBeforeNode(const Node& node)
247 // FIXME: This should ASSERT(node.parentNode())
248 // At least one caller currently hits this ASSERT though, which indicates
249 // that the caller is trying to make a position relative to a disconnected node (which is likely an error)
250 // Specifically, editing/deleting/delete-ligature-001.html crashes with ASSERT(node->parentNode())
251 return Position(node.parentNode(), node.nodeIndex(), Position::PositionIsOffsetInAnchor);
254 inline Position positionInParentAfterNode(const Node& node)
256 ASSERT(node.parentNode());
257 return Position(node.parentNode(), node.nodeIndex() + 1, Position::PositionIsOffsetInAnchor);
260 // positionBeforeNode and positionAfterNode return neighbor-anchored positions, construction is O(1)
261 inline Position positionBeforeNode(Node* anchorNode)
264 return Position(anchorNode, Position::PositionIsBeforeAnchor);
267 inline Position positionAfterNode(Node* anchorNode)
270 return Position(anchorNode, Position::PositionIsAfterAnchor);
273 inline int lastOffsetInNode(Node* node)
275 return node->offsetInCharacters() ? node->maxCharacterOffset() : static_cast<int>(node->countChildren());
278 // firstPositionInNode and lastPositionInNode return parent-anchored positions, lastPositionInNode construction is O(n) due to countChildren()
279 inline Position firstPositionInNode(Node* anchorNode)
281 if (anchorNode->isTextNode())
282 return Position(anchorNode, 0, Position::PositionIsOffsetInAnchor);
283 return Position(anchorNode, Position::PositionIsBeforeChildren);
286 inline Position lastPositionInNode(Node* anchorNode)
288 if (anchorNode->isTextNode())
289 return Position(anchorNode, lastOffsetInNode(anchorNode), Position::PositionIsOffsetInAnchor);
290 return Position(anchorNode, Position::PositionIsAfterChildren);
293 inline int minOffsetForNode(Node* anchorNode, int offset)
295 if (anchorNode->offsetInCharacters())
296 return std::min(offset, anchorNode->maxCharacterOffset());
299 for (Node* node = anchorNode->firstChild(); node && newOffset < offset; node = node->nextSibling())
305 inline bool offsetIsBeforeLastNodeOffset(int offset, Node* anchorNode)
307 if (anchorNode->offsetInCharacters())
308 return offset < anchorNode->maxCharacterOffset();
310 int currentOffset = 0;
311 for (Node* node = anchorNode->firstChild(); node && currentOffset < offset; node = node->nextSibling())
315 return offset < currentOffset;
318 class PositionWithAffinity {
320 PositionWithAffinity()
321 : m_affinity(DOWNSTREAM)
325 PositionWithAffinity(const Position& position, EAffinity affinity = DOWNSTREAM)
326 : m_position(position)
327 , m_affinity(affinity)
331 EAffinity affinity() const { return m_affinity; }
332 const Position& position() const { return m_position; }
336 EAffinity m_affinity;
339 } // namespace WebCore
342 // Outside the WebCore namespace for ease of invocation from gdb.
343 void showTree(const WebCore::Position&);
344 void showTree(const WebCore::Position*);