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
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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
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23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include "config.h"
27 #include "PositionIterator.h"
28 
29 #include "Node.h"
30 #include "RenderBlock.h"
31 #include "htmlediting.h"
32 
33 namespace WebCore {
34 
35 using namespace HTMLNames;
36 
operator Position() const37 PositionIterator::operator Position() const
38 {
39     if (m_nodeAfterPositionInAnchor) {
40         ASSERT(m_nodeAfterPositionInAnchor->parentNode() == m_anchorNode);
41         // FIXME: This check is inadaquete because any ancestor could be ignored by editing
42         if (editingIgnoresContent(m_nodeAfterPositionInAnchor->parentNode()))
43             return positionBeforeNode(m_anchorNode);
44         return positionInParentBeforeNode(m_nodeAfterPositionInAnchor);
45     }
46     if (m_anchorNode->hasChildNodes())
47         return lastPositionInOrAfterNode(m_anchorNode);
48     return Position(m_anchorNode, m_offsetInAnchor);
49 }
50 
increment()51 void PositionIterator::increment()
52 {
53     if (!m_anchorNode)
54         return;
55 
56     if (m_nodeAfterPositionInAnchor) {
57         m_anchorNode = m_nodeAfterPositionInAnchor;
58         m_nodeAfterPositionInAnchor = m_anchorNode->firstChild();
59         m_offsetInAnchor = 0;
60         return;
61     }
62 
63     if (!m_anchorNode->hasChildNodes() && m_offsetInAnchor < lastOffsetForEditing(m_anchorNode))
64         m_offsetInAnchor = Position::uncheckedNextOffset(m_anchorNode, m_offsetInAnchor);
65     else {
66         m_nodeAfterPositionInAnchor = m_anchorNode;
67         m_anchorNode = m_nodeAfterPositionInAnchor->parentNode();
68         m_nodeAfterPositionInAnchor = m_nodeAfterPositionInAnchor->nextSibling();
69         m_offsetInAnchor = 0;
70     }
71 }
72 
decrement()73 void PositionIterator::decrement()
74 {
75     if (!m_anchorNode)
76         return;
77 
78     if (m_nodeAfterPositionInAnchor) {
79         m_anchorNode = m_nodeAfterPositionInAnchor->previousSibling();
80         if (m_anchorNode) {
81             m_nodeAfterPositionInAnchor = 0;
82             m_offsetInAnchor = m_anchorNode->hasChildNodes() ? 0 : lastOffsetForEditing(m_anchorNode);
83         } else {
84             m_nodeAfterPositionInAnchor = m_nodeAfterPositionInAnchor->parentNode();
85             m_anchorNode = m_nodeAfterPositionInAnchor->parentNode();
86             m_offsetInAnchor = 0;
87         }
88         return;
89     }
90 
91     if (m_anchorNode->hasChildNodes()) {
92         m_anchorNode = m_anchorNode->lastChild();
93         m_offsetInAnchor = m_anchorNode->hasChildNodes()? 0: lastOffsetForEditing(m_anchorNode);
94     } else {
95         if (m_offsetInAnchor)
96             m_offsetInAnchor = Position::uncheckedPreviousOffset(m_anchorNode, m_offsetInAnchor);
97         else {
98             m_nodeAfterPositionInAnchor = m_anchorNode;
99             m_anchorNode = m_anchorNode->parentNode();
100         }
101     }
102 }
103 
setOffsetInLeafNode(int offset)104 void PositionIterator::setOffsetInLeafNode(int offset)
105 {
106     ASSERT(!m_anchorNode->hasChildNodes());
107     ASSERT(0 <= offset && offset <= lastOffsetForEditing(m_anchorNode));
108     m_offsetInAnchor = offset;
109 }
110 
atStart() const111 bool PositionIterator::atStart() const
112 {
113     if (!m_anchorNode)
114         return true;
115     if (m_anchorNode->parentNode())
116         return false;
117     return (!m_anchorNode->hasChildNodes() && !m_offsetInAnchor) || (m_nodeAfterPositionInAnchor && !m_nodeAfterPositionInAnchor->previousSibling());
118 }
119 
atEnd() const120 bool PositionIterator::atEnd() const
121 {
122     if (!m_anchorNode)
123         return true;
124     if (m_nodeAfterPositionInAnchor)
125         return false;
126     return !m_anchorNode->parentNode() && (m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode));
127 }
128 
atStartOfNode() const129 bool PositionIterator::atStartOfNode() const
130 {
131     if (!m_anchorNode)
132         return true;
133     if (!m_nodeAfterPositionInAnchor)
134         return !m_anchorNode->hasChildNodes() && !m_offsetInAnchor;
135     return !m_nodeAfterPositionInAnchor->previousSibling();
136 }
137 
atEndOfNode() const138 bool PositionIterator::atEndOfNode() const
139 {
140     if (!m_anchorNode)
141         return true;
142     if (m_nodeAfterPositionInAnchor)
143         return false;
144     return m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode);
145 }
146 
isCandidate() const147 bool PositionIterator::isCandidate() const
148 {
149     if (!m_anchorNode)
150         return false;
151 
152     RenderObject* renderer = m_anchorNode->renderer();
153     if (!renderer)
154         return false;
155 
156     if (renderer->style()->visibility() != VISIBLE)
157         return false;
158 
159     if (renderer->isBR())
160         return !m_offsetInAnchor && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
161 
162     if (renderer->isText())
163         return !Position::nodeIsUserSelectNone(m_anchorNode) && Position(*this).inRenderedText();
164 
165     if (isTableElement(m_anchorNode) || editingIgnoresContent(m_anchorNode))
166         return (atStartOfNode() || atEndOfNode()) && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
167 
168     if (!m_anchorNode->hasTagName(htmlTag) && renderer->isBlockFlow()) {
169         if (toRenderBlock(renderer)->height() || m_anchorNode->hasTagName(bodyTag)) {
170             if (!Position::hasRenderedNonAnonymousDescendantsWithHeight(renderer))
171                 return atStartOfNode() && !Position::nodeIsUserSelectNone(m_anchorNode);
172             return m_anchorNode->rendererIsEditable() && !Position::nodeIsUserSelectNone(m_anchorNode) && Position(*this).atEditingBoundary();
173         }
174     }
175 
176     return false;
177 }
178 
179 } // namespace WebCore
180