97812dd87b29e02d1dc8c186c86cfd9af96c605a
[WebKit-https.git] / Source / WebCore / dom / PositionIterator.cpp
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,
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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 "HTMLNames.h"
30 #include "RenderBlock.h"
31 #include "RenderText.h"
32 #include "htmlediting.h"
33
34 namespace WebCore {
35
36 using namespace HTMLNames;
37
38 PositionIterator::operator Position() const
39 {
40     if (m_nodeAfterPositionInAnchor) {
41         ASSERT(m_nodeAfterPositionInAnchor->parentNode() == m_anchorNode);
42         // FIXME: This check is inadaquete because any ancestor could be ignored by editing
43         if (editingIgnoresContent(m_nodeAfterPositionInAnchor->parentNode()))
44             return positionBeforeNode(m_anchorNode);
45         return positionInParentBeforeNode(m_nodeAfterPositionInAnchor);
46     }
47     if (m_anchorNode->hasChildNodes())
48         return lastPositionInOrAfterNode(m_anchorNode);
49     return createLegacyEditingPosition(m_anchorNode, m_offsetInAnchor);
50 }
51
52 void PositionIterator::increment()
53 {
54     if (!m_anchorNode)
55         return;
56
57     if (m_nodeAfterPositionInAnchor) {
58         m_anchorNode = m_nodeAfterPositionInAnchor;
59         m_nodeAfterPositionInAnchor = m_anchorNode->firstChild();
60         m_offsetInAnchor = 0;
61         return;
62     }
63
64     if (!m_anchorNode->hasChildNodes() && m_offsetInAnchor < lastOffsetForEditing(m_anchorNode))
65         m_offsetInAnchor = Position::uncheckedNextOffset(m_anchorNode, m_offsetInAnchor);
66     else {
67         m_nodeAfterPositionInAnchor = m_anchorNode;
68         m_anchorNode = m_nodeAfterPositionInAnchor->parentNode();
69         m_nodeAfterPositionInAnchor = m_nodeAfterPositionInAnchor->nextSibling();
70         m_offsetInAnchor = 0;
71     }
72 }
73
74 void PositionIterator::decrement()
75 {
76     if (!m_anchorNode)
77         return;
78
79     if (m_nodeAfterPositionInAnchor) {
80         m_anchorNode = m_nodeAfterPositionInAnchor->previousSibling();
81         if (m_anchorNode) {
82             m_nodeAfterPositionInAnchor = 0;
83             m_offsetInAnchor = m_anchorNode->hasChildNodes() ? 0 : lastOffsetForEditing(m_anchorNode);
84         } else {
85             m_nodeAfterPositionInAnchor = m_nodeAfterPositionInAnchor->parentNode();
86             m_anchorNode = m_nodeAfterPositionInAnchor->parentNode();
87             m_offsetInAnchor = 0;
88         }
89         return;
90     }
91     
92     if (m_anchorNode->hasChildNodes()) {
93         m_anchorNode = m_anchorNode->lastChild();
94         m_offsetInAnchor = m_anchorNode->hasChildNodes()? 0: lastOffsetForEditing(m_anchorNode);
95     } else {
96         if (m_offsetInAnchor)
97             m_offsetInAnchor = Position::uncheckedPreviousOffset(m_anchorNode, m_offsetInAnchor);
98         else {
99             m_nodeAfterPositionInAnchor = m_anchorNode;
100             m_anchorNode = m_anchorNode->parentNode();
101         }
102     }
103 }
104
105 bool PositionIterator::atStart() const
106 {
107     if (!m_anchorNode)
108         return true;
109     if (m_anchorNode->parentNode())
110         return false;
111     return (!m_anchorNode->hasChildNodes() && !m_offsetInAnchor) || (m_nodeAfterPositionInAnchor && !m_nodeAfterPositionInAnchor->previousSibling());
112 }
113
114 bool PositionIterator::atEnd() const
115 {
116     if (!m_anchorNode)
117         return true;
118     if (m_nodeAfterPositionInAnchor)
119         return false;
120     return !m_anchorNode->parentNode() && (m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode));
121 }
122
123 bool PositionIterator::atStartOfNode() const
124 {
125     if (!m_anchorNode)
126         return true;
127     if (!m_nodeAfterPositionInAnchor)
128         return !m_anchorNode->hasChildNodes() && !m_offsetInAnchor;
129     return !m_nodeAfterPositionInAnchor->previousSibling();
130 }
131
132 bool PositionIterator::atEndOfNode() const
133 {
134     if (!m_anchorNode)
135         return true;
136     if (m_nodeAfterPositionInAnchor)
137         return false;
138     return m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode);
139 }
140
141 bool PositionIterator::isCandidate() const
142 {
143     if (!m_anchorNode)
144         return false;
145
146     RenderObject* renderer = m_anchorNode->renderer();
147     if (!renderer)
148         return false;
149     
150     if (renderer->style().visibility() != VISIBLE)
151         return false;
152
153     if (renderer->isBR())
154         return !m_offsetInAnchor && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
155
156     if (renderer->isText())
157         return !Position::nodeIsUserSelectNone(m_anchorNode) && toRenderText(renderer)->containsCaretOffset(m_offsetInAnchor);
158
159     if (isRenderedTable(m_anchorNode) || editingIgnoresContent(m_anchorNode))
160         return (atStartOfNode() || atEndOfNode()) && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
161
162     if (!m_anchorNode->hasTagName(htmlTag) && renderer->isRenderBlockFlow()) {
163         RenderBlock& block = toRenderBlock(*renderer);
164         if (block.logicalHeight() || m_anchorNode->hasTagName(bodyTag)) {
165             if (!Position::hasRenderedNonAnonymousDescendantsWithHeight(block))
166                 return atStartOfNode() && !Position::nodeIsUserSelectNone(m_anchorNode);
167             return m_anchorNode->hasEditableStyle() && !Position::nodeIsUserSelectNone(m_anchorNode) && Position(*this).atEditingBoundary();
168         }
169     }
170
171     return false;
172 }
173
174 } // namespace WebCore