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#pragma once
27
28#include "Node.h"
29#include "Position.h"
30
31namespace WebCore {
32
33// A Position iterator with constant-time
34// increment, decrement, and several predicates on the Position it is at.
35// Conversion to/from Position is O(n) in the offset.
36class PositionIterator {
37public:
38 PositionIterator(const Position& pos)
39 : m_anchorNode(pos.anchorNode())
40 , m_nodeAfterPositionInAnchor(m_anchorNode->traverseToChildAt(pos.deprecatedEditingOffset()))
41 , m_offsetInAnchor(m_nodeAfterPositionInAnchor ? 0 : pos.deprecatedEditingOffset())
42 {
43 }
44 operator Position() const;
45
46 void increment();
47 void decrement();
48
49 Node* node() const { return m_anchorNode; }
50 int offsetInLeafNode() const { return m_offsetInAnchor; }
51
52 bool atStart() const;
53 bool atEnd() const;
54 bool atStartOfNode() const;
55 bool atEndOfNode() const;
56 bool isCandidate() const;
57
58private:
59 Node* m_anchorNode { nullptr };
60 Node* m_nodeAfterPositionInAnchor { nullptr }; // If this is non-null, m_nodeAfterPositionInAnchor->parentNode() == m_anchorNode;
61 int m_offsetInAnchor { 0 };
62};
63
64} // namespace WebCore
65