src/third_party/WebKit/Source/core/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,
  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 #include "config.h"
  27 #include "core/dom/PositionIterator.h"
  28
  29 #include "HTMLNames.h"
  30 #include "core/editing/htmlediting.h"
  31 #include "core/rendering/RenderBlock.h"
  32
  33 namespace WebCore {
  34
  35 using namespace HTMLNames;
  36
  37 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 createLegacyEditingPosition(m_anchorNode, m_offsetInAnchor);
  49 }
  50
  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
  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
 104 bool PositionIterator::atStart() const
 105 {
 106     if (!m_anchorNode)
 107         return true;
 108     if (m_anchorNode->parentNode())
 109         return false;
 110     return (!m_anchorNode->hasChildNodes() && !m_offsetInAnchor) || (m_nodeAfterPositionInAnchor && !m_nodeAfterPositionInAnchor->previousSibling());
 111 }
 112
 113 bool PositionIterator::atEnd() const
 114 {
 115     if (!m_anchorNode)
 116         return true;
 117     if (m_nodeAfterPositionInAnchor)
 118         return false;
 119     return !m_anchorNode->parentNode() && (m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode));
 120 }
 121
 122 bool PositionIterator::atStartOfNode() const
 123 {
 124     if (!m_anchorNode)
 125         return true;
 126     if (!m_nodeAfterPositionInAnchor)
 127         return !m_anchorNode->hasChildNodes() && !m_offsetInAnchor;
 128     return !m_nodeAfterPositionInAnchor->previousSibling();
 129 }
 130
 131 bool PositionIterator::atEndOfNode() const
 132 {
 133     if (!m_anchorNode)
 134         return true;
 135     if (m_nodeAfterPositionInAnchor)
 136         return false;
 137     return m_anchorNode->hasChildNodes() || m_offsetInAnchor >= lastOffsetForEditing(m_anchorNode);
 138 }
 139
 140 bool PositionIterator::isCandidate() const
 141 {
 142     if (!m_anchorNode)
 143         return false;
 144
 145     RenderObject* renderer = m_anchorNode->renderer();
 146     if (!renderer)
 147         return false;
 148
 149     if (renderer->style()->visibility() != VISIBLE)
 150         return false;
 151
 152     if (renderer->isBR())
 153         return !m_offsetInAnchor && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
 154
 155     if (renderer->isText())
 156         return !Position::nodeIsUserSelectNone(m_anchorNode) && Position(*this).inRenderedText();
 157
 158     if (isRenderedTableElement(m_anchorNode) || editingIgnoresContent(m_anchorNode))
 159         return (atStartOfNode() || atEndOfNode()) && !Position::nodeIsUserSelectNone(m_anchorNode->parentNode());
 160
 161     if (!m_anchorNode->hasTagName(htmlTag) && renderer->isRenderBlockFlow()) {
 162         if (toRenderBlock(renderer)->logicalHeight() || m_anchorNode->hasTagName(bodyTag)) {
 163             if (!Position::hasRenderedNonAnonymousDescendantsWithHeight(renderer))
 164                 return atStartOfNode() && !Position::nodeIsUserSelectNone(m_anchorNode);
 165             return m_anchorNode->rendererIsEditable() && !Position::nodeIsUserSelectNone(m_anchorNode) && Position(*this).atEditingBoundary();
 166         }
 167     }
 168
 169     return false;
 170 }
 171
 172 } // namespace WebCore