third_party/blink/renderer/core/dom/events/event_queue.h

/*
 * Copyright (C) 2010 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:
 * 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 COMPUTER, 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 COMPUTER, 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.
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 */

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_DOM_EVENTS_EVENT_QUEUE_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_DOM_EVENTS_EVENT_QUEUE_H_

#include "third_party/blink/public/platform/task_type.h"
#include "third_party/blink/renderer/core/execution_context/context_lifecycle_observer.h"
#include "third_party/blink/renderer/platform/wtf/linked_hash_set.h"

namespace blink {

class Event;
class ExecutionContext;

class CORE_EXPORT EventQueue final : public GarbageCollected<EventQueue>,
                                     public ContextLifecycleObserver {
  USING_GARBAGE_COLLECTED_MIXIN(EventQueue);

 public:
  EventQueue(ExecutionContext*, TaskType);
  ~EventQueue();

  void Trace(Visitor*) override;
  bool EnqueueEvent(const base::Location&, Event&);
  void CancelAllEvents();
  bool HasPendingEvents() const;

 private:
  bool RemoveEvent(Event&);
  void DispatchEvent(Event*);

  void ContextDestroyed(ExecutionContext*) override;
  void Close(ExecutionContext*);
  void DoCancelAllEvents(ExecutionContext*);

  const TaskType task_type_;
  HeapLinkedHashSet<Member<Event>> queued_events_;
  bool is_closed_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_DOM_EVENTS_EVENT_QUEUE_H_