1 /* 2 * Copyright (C) 2007, 2008 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 #ifndef PositionIterator_h 27 #define PositionIterator_h 28 29 #include "core/dom/Node.h" 30 #include "core/dom/NodeTraversal.h" 31 #include "core/dom/Position.h" 32 33 namespace blink { 34 35 // A Position iterator with constant-time 36 // increment, decrement, and several predicates on the Position it is at. 37 // Conversion to/from Position is O(n) in the offset. 38 class PositionIterator { 39 STACK_ALLOCATED(); 40 public: 41 PositionIterator() 42 : m_anchorNode(nullptr) 43 , m_nodeAfterPositionInAnchor(nullptr) 44 , m_offsetInAnchor(0) 45 { 46 } 47 48 PositionIterator(const Position& pos) 49 : m_anchorNode(pos.anchorNode()) 50 , m_nodeAfterPositionInAnchor(NodeTraversal::childAt(*m_anchorNode, pos.deprecatedEditingOffset())) 51 , m_offsetInAnchor(m_nodeAfterPositionInAnchor ? 0 : pos.deprecatedEditingOffset()) 52 { 53 } 54 operator Position() const; 55 56 void increment(); 57 void decrement(); 58 59 Node* node() const { return m_anchorNode; } 60 int offsetInLeafNode() const { return m_offsetInAnchor; } 61 62 bool atStart() const; 63 bool atEnd() const; 64 bool atStartOfNode() const; 65 bool atEndOfNode() const; 66 bool isCandidate() const; 67 68 private: 69 RawPtrWillBeMember<Node> m_anchorNode; 70 RawPtrWillBeMember<Node> m_nodeAfterPositionInAnchor; // If this is non-null, m_nodeAfterPositionInAnchor->parentNode() == m_anchorNode; 71 int m_offsetInAnchor; 72 }; 73 74 } // namespace blink 75 76 #endif // PositionIterator_h 77