1/*
2 * Copyright (C) 2011 Google 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 are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32
33#include "MutationObserverInterestGroup.h"
34
35#include "MutationObserverRegistration.h"
36#include "MutationRecord.h"
37
38namespace WebCore {
39
40std::unique_ptr<MutationObserverInterestGroup> MutationObserverInterestGroup::createIfNeeded(Node& target, MutationObserver::MutationType type, MutationRecordDeliveryOptions oldValueFlag, const QualifiedName* attributeName)
41{
42    ASSERT((type == MutationObserver::Attributes && attributeName) || !attributeName);
43    HashMap<MutationObserver*, MutationRecordDeliveryOptions> observers;
44    target.getRegisteredMutationObserversOfType(observers, type, attributeName);
45    if (observers.isEmpty())
46        return nullptr;
47
48    return std::make_unique<MutationObserverInterestGroup>(observers, oldValueFlag);
49}
50
51MutationObserverInterestGroup::MutationObserverInterestGroup(HashMap<MutationObserver*, MutationRecordDeliveryOptions>& observers, MutationRecordDeliveryOptions oldValueFlag)
52    : m_oldValueFlag(oldValueFlag)
53{
54    ASSERT(!observers.isEmpty());
55    m_observers.swap(observers);
56}
57
58bool MutationObserverInterestGroup::isOldValueRequested()
59{
60    for (HashMap<MutationObserver*, MutationRecordDeliveryOptions>::iterator iter = m_observers.begin(); iter != m_observers.end(); ++iter) {
61        if (hasOldValue(iter->value))
62            return true;
63    }
64    return false;
65}
66
67void MutationObserverInterestGroup::enqueueMutationRecord(PassRefPtr<MutationRecord> prpMutation)
68{
69    RefPtr<MutationRecord> mutation = prpMutation;
70    RefPtr<MutationRecord> mutationWithNullOldValue;
71    for (HashMap<MutationObserver*, MutationRecordDeliveryOptions>::iterator iter = m_observers.begin(); iter != m_observers.end(); ++iter) {
72        MutationObserver* observer = iter->key;
73        if (hasOldValue(iter->value)) {
74            observer->enqueueMutationRecord(mutation);
75            continue;
76        }
77        if (!mutationWithNullOldValue) {
78            if (mutation->oldValue().isNull())
79                mutationWithNullOldValue = mutation;
80            else
81                mutationWithNullOldValue = MutationRecord::createWithNullOldValue(mutation).get();
82        }
83        observer->enqueueMutationRecord(mutationWithNullOldValue);
84    }
85}
86
87} // namespace WebCore
88