gecko-dev/dom/events/EventListenerService.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_EventListenerService_h_
#define mozilla_EventListenerService_h_

#include "jsapi.h"
#include "mozilla/Attributes.h"
#include "nsAutoPtr.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIDOMEventListener.h"
#include "nsIEventListenerService.h"
#include "nsString.h"
#include "nsTObserverArray.h"
#include "nsDataHashtable.h"
#include "nsGkAtoms.h"

class nsIMutableArray;

namespace mozilla {
namespace dom {
class EventTarget;
} // namespace dom

template<typename T>
class Maybe;

class EventListenerChange final : public nsIEventListenerChange
{
public:
  explicit EventListenerChange(dom::EventTarget* aTarget);

  void AddChangedListenerName(nsIAtom* aEventName);

  NS_DECL_ISUPPORTS
  NS_DECL_NSIEVENTLISTENERCHANGE

protected:
  virtual ~EventListenerChange();
  nsCOMPtr<dom::EventTarget> mTarget;
  nsTArray<RefPtr<nsIAtom>> mChangedListenerNames;
};

class EventListenerInfo final : public nsIEventListenerInfo
{
public:
  EventListenerInfo(const nsAString& aType,
                    already_AddRefed<nsIDOMEventListener> aListener,
                    bool aCapturing,
                    bool aAllowsUntrusted,
                    bool aInSystemEventGroup)
    : mType(aType)
    , mListener(aListener)
    , mCapturing(aCapturing)
    , mAllowsUntrusted(aAllowsUntrusted)
    , mInSystemEventGroup(aInSystemEventGroup)
  {
  }

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_CLASS(EventListenerInfo)
  NS_DECL_NSIEVENTLISTENERINFO

protected:
  virtual ~EventListenerInfo() {}

  bool GetJSVal(JSContext* aCx,
                Maybe<JSAutoCompartment>& aAc,
                JS::MutableHandle<JS::Value> aJSVal);

  nsString mType;
  // nsReftPtr because that is what nsListenerStruct uses too.
  RefPtr<nsIDOMEventListener> mListener;
  bool mCapturing;
  bool mAllowsUntrusted;
  bool mInSystemEventGroup;
};

class EventListenerService final : public nsIEventListenerService
{
  ~EventListenerService();
public:
  EventListenerService();
  NS_DECL_ISUPPORTS
  NS_DECL_NSIEVENTLISTENERSERVICE

  static void NotifyAboutMainThreadListenerChange(dom::EventTarget* aTarget,
                                                  nsIAtom* aName)
  {
    if (sInstance) {
      sInstance->NotifyAboutMainThreadListenerChangeInternal(aTarget, aName);
    }
  }

  void NotifyPendingChanges();
private:
  void NotifyAboutMainThreadListenerChangeInternal(dom::EventTarget* aTarget,
                                                   nsIAtom* aName);
  nsTObserverArray<nsCOMPtr<nsIListenerChangeListener>> mChangeListeners;
  nsCOMPtr<nsIMutableArray> mPendingListenerChanges;
  nsDataHashtable<nsISupportsHashKey, RefPtr<EventListenerChange>> mPendingListenerChangesSet;

  static EventListenerService* sInstance;
};

} // namespace mozilla

#endif // mozilla_EventListenerService_h_