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