| /* |
| * Copyright (C) 2007, 2008 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "core/editing/PositionIterator.h" |
| |
| namespace blink { |
| |
| static const int kInvalidOffset = -1; |
| |
| template <typename Strategy> |
| PositionIteratorAlgorithm<Strategy>::PositionIteratorAlgorithm(Node* anchorNode, int offsetInAnchor) |
| : m_anchorNode(anchorNode) |
| , m_nodeAfterPositionInAnchor(Strategy::childAt(*anchorNode, offsetInAnchor)) |
| , m_offsetInAnchor(m_nodeAfterPositionInAnchor ? 0 : offsetInAnchor) |
| , m_depthToAnchorNode(0) |
| , m_domTreeVersion(anchorNode->document().domTreeVersion()) |
| { |
| for (Node* node = Strategy::parent(*anchorNode); node; node = Strategy::parent(*node)) { |
| // Each m_offsetsInAnchorNode[offset] should be an index of node in |
| // parent, but delay to calculate the index until it is needed for |
| // performance. |
| m_offsetsInAnchorNode.append(kInvalidOffset); |
| ++m_depthToAnchorNode; |
| } |
| if (m_nodeAfterPositionInAnchor) |
| m_offsetsInAnchorNode.append(offsetInAnchor); |
| } |
| template <typename Strategy> |
| PositionIteratorAlgorithm<Strategy>::PositionIteratorAlgorithm(const PositionTemplate<Strategy>& pos) |
| : PositionIteratorAlgorithm(pos.anchorNode(), pos.computeEditingOffset()) |
| { |
| } |
| |
| template <typename Strategy> |
| PositionIteratorAlgorithm<Strategy>::PositionIteratorAlgorithm() |
| : m_anchorNode(nullptr) |
| , m_nodeAfterPositionInAnchor(nullptr) |
| , m_offsetInAnchor(0) |
| , m_depthToAnchorNode(0) |
| , m_domTreeVersion(0) |
| { |
| } |
| |
| template <typename Strategy> |
| PositionTemplate<Strategy> PositionIteratorAlgorithm<Strategy>::deprecatedComputePosition() const |
| { |
| // TODO(yoichio): Share code to check domTreeVersion with EphemeralRange. |
| ASSERT(isValid()); |
| if (m_nodeAfterPositionInAnchor) { |
| ASSERT(Strategy::parent(*m_nodeAfterPositionInAnchor) == m_anchorNode); |
| ASSERT(m_offsetsInAnchorNode[m_depthToAnchorNode] != kInvalidOffset); |
| // FIXME: This check is inadaquete because any ancestor could be ignored by editing |
| if (Strategy::editingIgnoresContent(Strategy::parent(*m_nodeAfterPositionInAnchor))) |
| return PositionTemplate<Strategy>::beforeNode(m_anchorNode); |
| return PositionTemplate<Strategy>(m_anchorNode, m_offsetsInAnchorNode[m_depthToAnchorNode]); |
| } |
| if (Strategy::hasChildren(*m_anchorNode)) |
| return PositionTemplate<Strategy>::lastPositionInOrAfterNode(m_anchorNode); |
| return PositionTemplate<Strategy>::editingPositionOf(m_anchorNode, m_offsetInAnchor); |
| } |
| |
| template <typename Strategy> |
| PositionTemplate<Strategy> PositionIteratorAlgorithm<Strategy>::computePosition() const |
| { |
| ASSERT(isValid()); |
| // Assume that we have the following DOM tree: |
| // A |
| // |-B |
| // | |-E |
| // | +-F |
| // | |
| // |-C |
| // +-D |
| // |-G |
| // +-H |
| if (m_nodeAfterPositionInAnchor) { |
| // For example, position is before E, F. |
| ASSERT(Strategy::parent(*m_nodeAfterPositionInAnchor) == m_anchorNode); |
| ASSERT(m_offsetsInAnchorNode[m_depthToAnchorNode] != kInvalidOffset); |
| // TODO(yoichio): This should be equivalent to |
| // PositionTemplate<Strategy>(m_anchorNode, PositionAnchorType::BeforeAnchor); |
| return PositionTemplate<Strategy>(m_anchorNode, m_offsetsInAnchorNode[m_depthToAnchorNode]); |
| } |
| if (Strategy::hasChildren(*m_anchorNode)) |
| // For example, position is the end of B. |
| return PositionTemplate<Strategy>::lastPositionInOrAfterNode(m_anchorNode); |
| if (m_anchorNode->isTextNode()) |
| return PositionTemplate<Strategy>(m_anchorNode, m_offsetInAnchor); |
| if (m_offsetInAnchor) |
| // For example, position is after G. |
| return PositionTemplate<Strategy>(m_anchorNode, PositionAnchorType::AfterAnchor); |
| // For example, position is before G. |
| return PositionTemplate<Strategy>(m_anchorNode, PositionAnchorType::BeforeAnchor); |
| } |
| |
| template <typename Strategy> |
| void PositionIteratorAlgorithm<Strategy>::increment() |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return; |
| |
| // Assume that we have the following DOM tree: |
| // A |
| // |-B |
| // | |-E |
| // | +-F |
| // | |
| // |-C |
| // +-D |
| // |-G |
| // +-H |
| // Let |anchor| as |m_anchorNode| and |
| // |child| as |m_nodeAfterPositionInAnchor|. |
| if (m_nodeAfterPositionInAnchor) { |
| // Case #1: Move to position before the first child of |
| // |m_nodeAfterPositionInAnchor|. |
| // This is a point just before |child|. |
| // Let |anchor| is A and |child| is B, |
| // then next |anchor| is B and |child| is E. |
| m_anchorNode = m_nodeAfterPositionInAnchor; |
| m_nodeAfterPositionInAnchor = Strategy::firstChild(*m_anchorNode); |
| m_offsetInAnchor = 0; |
| // Increment depth intializing with 0. |
| ++m_depthToAnchorNode; |
| if (m_depthToAnchorNode == m_offsetsInAnchorNode.size()) |
| m_offsetsInAnchorNode.append(0); |
| else |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = 0; |
| return; |
| } |
| |
| if (m_anchorNode->layoutObject() && !Strategy::hasChildren(*m_anchorNode) && m_offsetInAnchor < Strategy::lastOffsetForEditing(m_anchorNode)) { |
| // Case #2. This is the next of Case #1 or #2 itself. |
| // Position is (|anchor|, |m_offsetInAchor|). |
| // In this case |anchor| is a leaf(E,F,C,G or H) and |
| // |m_offsetInAnchor| is not on the end of |anchor|. |
| // Then just increment |m_offsetInAnchor|. |
| m_offsetInAnchor = uncheckedNextOffset(m_anchorNode, m_offsetInAnchor); |
| } else { |
| // Case #3. This is the next of Case #2 or #3. |
| // Position is the end of |anchor|. |
| // 3-a. If |anchor| has next sibling (let E), |
| // next |anchor| is B and |child| is F (next is Case #1.) |
| // 3-b. If |anchor| doesn't have next sibling (let F), |
| // next |anchor| is B and |child| is null. (next is Case #3.) |
| m_nodeAfterPositionInAnchor = m_anchorNode; |
| m_anchorNode = Strategy::parent(*m_nodeAfterPositionInAnchor); |
| if (!m_anchorNode) |
| return; |
| ASSERT(m_depthToAnchorNode > 0); |
| --m_depthToAnchorNode; |
| // Increment offset of |child| or initialize if it have never been |
| // used. |
| if (m_offsetsInAnchorNode[m_depthToAnchorNode] == kInvalidOffset) |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = Strategy::index(*m_nodeAfterPositionInAnchor) + 1; |
| else |
| ++m_offsetsInAnchorNode[m_depthToAnchorNode]; |
| m_nodeAfterPositionInAnchor = Strategy::nextSibling(*m_nodeAfterPositionInAnchor); |
| m_offsetInAnchor = 0; |
| } |
| } |
| |
| template <typename Strategy> |
| void PositionIteratorAlgorithm<Strategy>::decrement() |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return; |
| |
| // Assume that we have the following DOM tree: |
| // A |
| // |-B |
| // | |-E |
| // | +-F |
| // | |
| // |-C |
| // +-D |
| // |-G |
| // +-H |
| // Let |anchor| as |m_anchorNode| and |
| // |child| as |m_nodeAfterPositionInAnchor|. |
| // decrement() is complex but logically reverse of increment(), of course:) |
| if (m_nodeAfterPositionInAnchor) { |
| m_anchorNode = Strategy::previousSibling(*m_nodeAfterPositionInAnchor); |
| if (m_anchorNode) { |
| // Case #1-a. This is a revese of increment()::Case#3-a. |
| // |child| has a previous sibling. |
| // Let |anchor| is B and |child| is F, |
| // next |anchor| is E and |child| is null. |
| m_nodeAfterPositionInAnchor = nullptr; |
| m_offsetInAnchor = Strategy::hasChildren(*m_anchorNode) ? 0 : Strategy::lastOffsetForEditing(m_anchorNode); |
| // Decrement offset of |child| or initialize if it have never been |
| // used. |
| if (m_offsetsInAnchorNode[m_depthToAnchorNode] == kInvalidOffset) |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = Strategy::index(*m_nodeAfterPositionInAnchor); |
| else |
| --m_offsetsInAnchorNode[m_depthToAnchorNode]; |
| ASSERT(m_offsetsInAnchorNode[m_depthToAnchorNode] >= 0); |
| // Increment depth intializing with last offset. |
| ++m_depthToAnchorNode; |
| if (m_depthToAnchorNode >= m_offsetsInAnchorNode.size()) |
| m_offsetsInAnchorNode.append(m_offsetInAnchor); |
| else |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = m_offsetInAnchor; |
| return; |
| } else { |
| // Case #1-b. This is a revese of increment()::Case#1. |
| // |child| doesn't have a previous sibling. |
| // Let |anchor| is B and |child| is E, |
| // next |anchor| is A and |child| is B. |
| m_nodeAfterPositionInAnchor = Strategy::parent(*m_nodeAfterPositionInAnchor); |
| m_anchorNode = Strategy::parent(*m_nodeAfterPositionInAnchor); |
| if (!m_anchorNode) |
| return; |
| m_offsetInAnchor = 0; |
| // Decrement depth and intialize if needs. |
| ASSERT(m_depthToAnchorNode > 0); |
| --m_depthToAnchorNode; |
| if (m_offsetsInAnchorNode[m_depthToAnchorNode] == kInvalidOffset) |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = Strategy::index(*m_nodeAfterPositionInAnchor); |
| } |
| return; |
| } |
| |
| if (Strategy::hasChildren(*m_anchorNode)) { |
| // Case #2. This is a reverse of increment()::Case3-b. |
| // Let |anchor| is B, next |anchor| is F. |
| m_anchorNode = Strategy::lastChild(*m_anchorNode); |
| m_offsetInAnchor = Strategy::hasChildren(*m_anchorNode)? 0 : Strategy::lastOffsetForEditing(m_anchorNode); |
| // Decrement depth initializing with -1 because |
| // |m_nodeAfterPositionInAnchor| is null so still unneeded. |
| if (m_depthToAnchorNode >= m_offsetsInAnchorNode.size()) |
| m_offsetsInAnchorNode.append(kInvalidOffset); |
| else |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = kInvalidOffset; |
| ++m_depthToAnchorNode; |
| return; |
| } else { |
| if (m_offsetInAnchor && m_anchorNode->layoutObject()) { |
| // Case #3-a. This is a reverse of increment()::Case#2. |
| // In this case |anchor| is a leaf(E,F,C,G or H) and |
| // |m_offsetInAnchor| is not on the beginning of |anchor|. |
| // Then just decrement |m_offsetInAnchor|. |
| m_offsetInAnchor = uncheckedPreviousOffset(m_anchorNode, m_offsetInAnchor); |
| return; |
| } else { |
| // Case #3-b. This is a reverse of increment()::Case#1. |
| // In this case |anchor| is a leaf(E,F,C,G or H) and |
| // |m_offsetInAnchor| is on the beginning of |anchor|. |
| // Let |anchor| is E, |
| // next |anchor| is B and |child| is E. |
| m_nodeAfterPositionInAnchor = m_anchorNode; |
| m_anchorNode = Strategy::parent(*m_anchorNode); |
| if (!m_anchorNode) |
| return; |
| ASSERT(m_depthToAnchorNode > 0); |
| --m_depthToAnchorNode; |
| if (m_offsetsInAnchorNode[m_depthToAnchorNode] == kInvalidOffset) |
| m_offsetsInAnchorNode[m_depthToAnchorNode] = Strategy::index(*m_nodeAfterPositionInAnchor); |
| } |
| } |
| } |
| |
| template <typename Strategy> |
| bool PositionIteratorAlgorithm<Strategy>::atStart() const |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return true; |
| if (Strategy::parent(*m_anchorNode)) |
| return false; |
| return (!Strategy::hasChildren(*m_anchorNode) && !m_offsetInAnchor) || (m_nodeAfterPositionInAnchor && !Strategy::previousSibling(*m_nodeAfterPositionInAnchor)); |
| } |
| |
| template <typename Strategy> |
| bool PositionIteratorAlgorithm<Strategy>::atEnd() const |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return true; |
| if (m_nodeAfterPositionInAnchor) |
| return false; |
| return !Strategy::parent(*m_anchorNode) && (Strategy::hasChildren(*m_anchorNode) || m_offsetInAnchor >= Strategy::lastOffsetForEditing(m_anchorNode)); |
| } |
| |
| template <typename Strategy> |
| bool PositionIteratorAlgorithm<Strategy>::atStartOfNode() const |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return true; |
| if (!m_nodeAfterPositionInAnchor) |
| return !Strategy::hasChildren(*m_anchorNode) && !m_offsetInAnchor; |
| return !Strategy::previousSibling(*m_nodeAfterPositionInAnchor); |
| } |
| |
| template <typename Strategy> |
| bool PositionIteratorAlgorithm<Strategy>::atEndOfNode() const |
| { |
| ASSERT(isValid()); |
| if (!m_anchorNode) |
| return true; |
| if (m_nodeAfterPositionInAnchor) |
| return false; |
| return Strategy::hasChildren(*m_anchorNode) || m_offsetInAnchor >= Strategy::lastOffsetForEditing(m_anchorNode); |
| } |
| |
| template class PositionIteratorAlgorithm<EditingStrategy>; |
| template class PositionIteratorAlgorithm<EditingInComposedTreeStrategy>; |
| |
| } // namespace blink |
