1/*
2 * Copyright (C) 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 RangeBoundaryPoint_h
27#define RangeBoundaryPoint_h
28
29#include "core/dom/Node.h"
30#include "core/dom/NodeTraversal.h"
31#include "core/dom/Position.h"
32
33namespace blink {
34
35class RangeBoundaryPoint {
36    DISALLOW_ALLOCATION();
37public:
38    explicit RangeBoundaryPoint(PassRefPtrWillBeRawPtr<Node> container);
39
40    explicit RangeBoundaryPoint(const RangeBoundaryPoint&);
41
42    const Position toPosition() const;
43
44    Node* container() const;
45    int offset() const;
46    Node* childBefore() const;
47
48    void clear();
49
50    void set(PassRefPtrWillBeRawPtr<Node> container, int offset, Node* childBefore);
51    void setOffset(int offset);
52
53    void setToBeforeChild(Node&);
54    void setToStartOfNode(Node&);
55    void setToEndOfNode(Node&);
56
57    void childBeforeWillBeRemoved();
58    void invalidateOffset() const;
59    void ensureOffsetIsValid() const;
60
61    void trace(Visitor*);
62
63private:
64    static const int invalidOffset = -1;
65
66    RefPtrWillBeMember<Node> m_containerNode;
67    mutable int m_offsetInContainer;
68    RefPtrWillBeMember<Node> m_childBeforeBoundary;
69};
70
71inline RangeBoundaryPoint::RangeBoundaryPoint(PassRefPtrWillBeRawPtr<Node> container)
72    : m_containerNode(container)
73    , m_offsetInContainer(0)
74    , m_childBeforeBoundary(nullptr)
75{
76    ASSERT(m_containerNode);
77}
78
79inline RangeBoundaryPoint::RangeBoundaryPoint(const RangeBoundaryPoint& other)
80    : m_containerNode(other.container())
81    , m_offsetInContainer(other.offset())
82    , m_childBeforeBoundary(other.childBefore())
83{
84}
85
86inline Node* RangeBoundaryPoint::container() const
87{
88    return m_containerNode.get();
89}
90
91inline Node* RangeBoundaryPoint::childBefore() const
92{
93    return m_childBeforeBoundary.get();
94}
95
96inline void RangeBoundaryPoint::ensureOffsetIsValid() const
97{
98    if (m_offsetInContainer >= 0)
99        return;
100
101    ASSERT(m_childBeforeBoundary);
102    m_offsetInContainer = m_childBeforeBoundary->nodeIndex() + 1;
103}
104
105inline const Position RangeBoundaryPoint::toPosition() const
106{
107    ensureOffsetIsValid();
108    return createLegacyEditingPosition(m_containerNode.get(), m_offsetInContainer);
109}
110
111inline int RangeBoundaryPoint::offset() const
112{
113    ensureOffsetIsValid();
114    return m_offsetInContainer;
115}
116
117inline void RangeBoundaryPoint::clear()
118{
119    m_containerNode.clear();
120    m_offsetInContainer = 0;
121    m_childBeforeBoundary = nullptr;
122}
123
124inline void RangeBoundaryPoint::set(PassRefPtrWillBeRawPtr<Node> container, int offset, Node* childBefore)
125{
126    ASSERT(container);
127    ASSERT(offset >= 0);
128    ASSERT(childBefore == (offset ? NodeTraversal::childAt(*container, offset - 1) : 0));
129    m_containerNode = container;
130    m_offsetInContainer = offset;
131    m_childBeforeBoundary = childBefore;
132}
133
134inline void RangeBoundaryPoint::setOffset(int offset)
135{
136    ASSERT(m_containerNode);
137    ASSERT(m_containerNode->offsetInCharacters());
138    ASSERT(m_offsetInContainer >= 0);
139    ASSERT(!m_childBeforeBoundary);
140    m_offsetInContainer = offset;
141}
142
143inline void RangeBoundaryPoint::setToBeforeChild(Node& child)
144{
145    ASSERT(child.parentNode());
146    m_childBeforeBoundary = child.previousSibling();
147    m_containerNode = child.parentNode();
148    m_offsetInContainer = m_childBeforeBoundary ? invalidOffset : 0;
149}
150
151inline void RangeBoundaryPoint::setToStartOfNode(Node& container)
152{
153    m_containerNode = &container;
154    m_offsetInContainer = 0;
155    m_childBeforeBoundary = nullptr;
156}
157
158inline void RangeBoundaryPoint::setToEndOfNode(Node& container)
159{
160    m_containerNode = &container;
161    if (m_containerNode->offsetInCharacters()) {
162        m_offsetInContainer = m_containerNode->maxCharacterOffset();
163        m_childBeforeBoundary = nullptr;
164    } else {
165        m_childBeforeBoundary = m_containerNode->lastChild();
166        m_offsetInContainer = m_childBeforeBoundary ? invalidOffset : 0;
167    }
168}
169
170inline void RangeBoundaryPoint::childBeforeWillBeRemoved()
171{
172    ASSERT(m_offsetInContainer);
173    m_childBeforeBoundary = m_childBeforeBoundary->previousSibling();
174    if (!m_childBeforeBoundary)
175        m_offsetInContainer = 0;
176    else if (m_offsetInContainer > 0)
177        --m_offsetInContainer;
178}
179
180inline void RangeBoundaryPoint::invalidateOffset() const
181{
182    m_offsetInContainer = invalidOffset;
183}
184
185inline void RangeBoundaryPoint::trace(Visitor* visitor)
186{
187    visitor->trace(m_containerNode);
188    visitor->trace(m_childBeforeBoundary);
189}
190
191inline bool operator==(const RangeBoundaryPoint& a, const RangeBoundaryPoint& b)
192{
193    if (a.container() != b.container())
194        return false;
195    if (a.childBefore() || b.childBefore()) {
196        if (a.childBefore() != b.childBefore())
197            return false;
198    } else {
199        if (a.offset() != b.offset())
200            return false;
201    }
202    return true;
203}
204
205}
206
207#endif
208