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/*
* Copyright (C) 2011 Google 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:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE COPYRIGHT
* OWNER 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 "config.h"
#include "ChildListMutationScope.h"
#include "MutationObserverInterestGroup.h"
#include "MutationRecord.h"
#include "StaticNodeList.h"
#include <wtf/NeverDestroyed.h>
#include <wtf/StdLibExtras.h>
namespace WebCore {
typedef HashMap<ContainerNode*, ChildListMutationAccumulator*> AccumulatorMap;
static AccumulatorMap& accumulatorMap()
{
static NeverDestroyed<AccumulatorMap> map;
return map;
}
ChildListMutationAccumulator::ChildListMutationAccumulator(ContainerNode& target, std::unique_ptr<MutationObserverInterestGroup> observers)
: m_target(target)
, m_lastAdded(nullptr)
, m_observers(WTFMove(observers))
{
}
ChildListMutationAccumulator::~ChildListMutationAccumulator()
{
if (!isEmpty())
enqueueMutationRecord();
accumulatorMap().remove(m_target.ptr());
}
Ref<ChildListMutationAccumulator> ChildListMutationAccumulator::getOrCreate(ContainerNode& target)
{
AccumulatorMap::AddResult result = accumulatorMap().add(&target, nullptr);
RefPtr<ChildListMutationAccumulator> accumulator;
if (!result.isNewEntry)
accumulator = result.iterator->value;
else {
accumulator = adoptRef(new ChildListMutationAccumulator(target, MutationObserverInterestGroup::createForChildListMutation(target)));
result.iterator->value = accumulator.get();
}
ASSERT(accumulator);
return accumulator.releaseNonNull();
}
inline bool ChildListMutationAccumulator::isAddedNodeInOrder(Node& child)
{
return isEmpty() || (m_lastAdded == child.previousSibling() && m_nextSibling == child.nextSibling());
}
void ChildListMutationAccumulator::childAdded(Node& childRef)
{
ASSERT(hasObservers());
Ref<Node> child(childRef);
if (!isAddedNodeInOrder(child))
enqueueMutationRecord();
if (isEmpty()) {
m_previousSibling = child->previousSibling();
m_nextSibling = child->nextSibling();
}
m_lastAdded = child.ptr();
m_addedNodes.append(child.get());
}
inline bool ChildListMutationAccumulator::isRemovedNodeInOrder(Node& child)
{
return isEmpty() || m_nextSibling == &child;
}
void ChildListMutationAccumulator::willRemoveChild(Node& childRef)
{
ASSERT(hasObservers());
Ref<Node> child(childRef);
if (!m_addedNodes.isEmpty() || !isRemovedNodeInOrder(child))
enqueueMutationRecord();
if (isEmpty()) {
m_previousSibling = child->previousSibling();
m_nextSibling = child->nextSibling();
m_lastAdded = child->previousSibling();
} else
m_nextSibling = child->nextSibling();
m_removedNodes.append(child.get());
}
void ChildListMutationAccumulator::enqueueMutationRecord()
{
ASSERT(hasObservers());
ASSERT(!isEmpty());
auto record = MutationRecord::createChildList(m_target, StaticNodeList::create(WTFMove(m_addedNodes)), StaticNodeList::create(WTFMove(m_removedNodes)), WTFMove(m_previousSibling), WTFMove(m_nextSibling));
m_observers->enqueueMutationRecord(WTFMove(record));
m_lastAdded = nullptr;
ASSERT(isEmpty());
}
bool ChildListMutationAccumulator::isEmpty()
{
bool result = m_removedNodes.isEmpty() && m_addedNodes.isEmpty();
#ifndef NDEBUG
if (result) {
ASSERT(!m_previousSibling);
ASSERT(!m_nextSibling);
ASSERT(!m_lastAdded);
}
#endif
return result;
}
} // namespace WebCore