text: /*
   * 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 "core/dom/MutationObserverInterestGroup.h"
  
  #include "core/dom/MutationRecord.h"
  
  namespace blink {
  
  PassOwnPtr<MutationObserverInterestGroup> MutationObserverInterestGroup::createIfNeeded(Node& target, MutationObserver::MutationType type, MutationRecordDeliveryOptions oldValueFlag, const QualifiedName* attributeName)
  {
      ASSERT((type == MutationObserver::Attributes && attributeName) || !attributeName);
      HashMap<RawPtr<MutationObserver>, MutationRecordDeliveryOptions> observers;
      target.getRegisteredMutationObserversOfType(observers, type, attributeName);
      if (observers.isEmpty())
          return nullptr;
  
      return adoptPtr(new MutationObserverInterestGroup(observers, oldValueFlag));
  }
  
  MutationObserverInterestGroup::MutationObserverInterestGroup(HashMap<RawPtr<MutationObserver>, MutationRecordDeliveryOptions>& observers, MutationRecordDeliveryOptions oldValueFlag)
      : m_oldValueFlag(oldValueFlag)
  {
      ASSERT(!observers.isEmpty());
      m_observers.swap(observers);
  }
  
  bool MutationObserverInterestGroup::isOldValueRequested()
  {
      for (HashMap<RawPtr<MutationObserver>, MutationRecordDeliveryOptions>::iterator iter = m_observers.begin(); iter != m_observers.end(); ++iter) {
          if (hasOldValue(iter->value))
              return true;
      }
      return false;
  }
  
  void MutationObserverInterestGroup::enqueueMutationRecord(PassRefPtr<MutationRecord> prpMutation)
  {
      RefPtr<MutationRecord> mutation = prpMutation;
      RefPtr<MutationRecord> mutationWithNullOldValue = nullptr;
      for (HashMap<RawPtr<MutationObserver>, MutationRecordDeliveryOptions>::iterator iter = m_observers.begin(); iter != m_observers.end(); ++iter) {
          MutationObserver* observer = iter->key;
          if (hasOldValue(iter->value)) {
              observer->enqueueMutationRecord(mutation);
              continue;
          }
          if (!mutationWithNullOldValue) {
              if (mutation->oldValue().isNull())
                  mutationWithNullOldValue = mutation;
              else
                  mutationWithNullOldValue = MutationRecord::createWithNullOldValue(mutation).get();
          }
          observer->enqueueMutationRecord(mutationWithNullOldValue);
      }
  }
  
  } // namespace blink
  