/* -*- 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_DOMEventTargetHelper_h_

#define mozilla_DOMEventTargetHelper_h_

#include "nsCOMPtr.h"

#include "nsGkAtoms.h"

#include "nsCycleCollectionParticipant.h"

#include "nsPIDOMWindow.h"

#include "nsIScriptGlobalObject.h"

#include "nsIScriptContext.h"

#include "nsIWeakReferenceUtils.h"

#include "MainThreadUtils.h"

#include "mozilla/Attributes.h"

#include "mozilla/EventListenerManager.h"

#include "mozilla/dom/EventTarget.h"

struct JSCompartment;

class nsIDocument;

namespace mozilla {

class ErrorResult;

#define NS_DOMEVENTTARGETHELPER_IID                  \

  {                                                  \

    0xa28385c6, 0x9451, 0x4d7e, {                    \

      0xa3, 0xdd, 0xf4, 0xb6, 0x87, 0x2f, 0xa4, 0x76 \

    }                                                \

  }

class DOMEventTargetHelper : public dom::EventTarget {

 public:

  DOMEventTargetHelper()

      : mParentObject(nullptr),

        mOwnerWindow(nullptr),

        mHasOrHasHadOwnerWindow(false),

        mIsKeptAlive(false) {}

  explicit DOMEventTargetHelper(nsPIDOMWindowInner* aWindow)

      : mParentObject(nullptr),

        mOwnerWindow(nullptr),

        mHasOrHasHadOwnerWindow(false),

        mIsKeptAlive(false) {

    BindToOwner(aWindow);

  }

  explicit DOMEventTargetHelper(nsIGlobalObject* aGlobalObject)

      : mParentObject(nullptr),

        mOwnerWindow(nullptr),

        mHasOrHasHadOwnerWindow(false),

        mIsKeptAlive(false) {

    BindToOwner(aGlobalObject);

  }

  explicit DOMEventTargetHelper(DOMEventTargetHelper* aOther)

      : mParentObject(nullptr),

        mOwnerWindow(nullptr),

        mHasOrHasHadOwnerWindow(false),

        mIsKeptAlive(false) {

    BindToOwner(aOther);

  }

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS

  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(DOMEventTargetHelper)

  NS_DECL_NSIDOMEVENTTARGET

  virtual EventListenerManager* GetExistingListenerManager() const override;

  virtual EventListenerManager* GetOrCreateListenerManager() override;

  using dom::EventTarget::RemoveEventListener;

  virtual void AddEventListener(

      const nsAString& aType, dom::EventListener* aListener,

      const dom::AddEventListenerOptionsOrBoolean& aOptions,

      const dom::Nullable<bool>& aWantsUntrusted, ErrorResult& aRv) override;

  NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOMEVENTTARGETHELPER_IID)

  void GetParentObject(nsIScriptGlobalObject** aParentObject) {

    if (mParentObject) {

      CallQueryInterface(mParentObject, aParentObject);

    } else {

      *aParentObject = nullptr;

    }

  }

  static DOMEventTargetHelper* FromSupports(nsISupports* aSupports) {

    dom::EventTarget* target = static_cast<dom::EventTarget*>(aSupports);

#ifdef DEBUG

    {

      nsCOMPtr<dom::EventTarget> target_qi = do_QueryInterface(aSupports);

      // If this assertion fires the QI implementation for the object in

      // question doesn't use the EventTarget pointer as the

      // nsISupports pointer. That must be fixed, or we'll crash...

      NS_ASSERTION(target_qi == target, "Uh, fix QI!");

    }

#endif

    return static_cast<DOMEventTargetHelper*>(target);

  }

  bool HasListenersFor(const nsAString& aType) {

    return mListenerManager && mListenerManager->HasListenersFor(aType);

  }

  bool HasListenersFor(nsAtom* aTypeWithOn) {

    return mListenerManager && mListenerManager->HasListenersFor(aTypeWithOn);

  }

  virtual nsPIDOMWindowOuter* GetOwnerGlobalForBindings() override {

    return nsPIDOMWindowOuter::GetFromCurrentInner(GetOwner());

  }

  nsresult CheckInnerWindowCorrectness() const {

    NS_ENSURE_STATE(!mHasOrHasHadOwnerWindow || mOwnerWindow);

    if (mOwnerWindow && !mOwnerWindow->IsCurrentInnerWindow()) {

      return NS_ERROR_FAILURE;

    }

    return NS_OK;

  }

  nsPIDOMWindowInner* GetOwner() const { return mOwnerWindow; }

  // Like GetOwner, but only returns non-null if the window being returned is

  // current (in the "current document" sense of the HTML spec).

  nsPIDOMWindowInner* GetWindowIfCurrent() const;

  // Returns the document associated with this event target, if that document is

  // the current document of its browsing context.  Will return null otherwise.

  nsIDocument* GetDocumentIfCurrent() const;

  void BindToOwner(nsIGlobalObject* aOwner);

  void BindToOwner(nsPIDOMWindowInner* aOwner);

  void BindToOwner(DOMEventTargetHelper* aOther);

  virtual void DisconnectFromOwner();

  using EventTarget::GetParentObject;

  virtual nsIGlobalObject* GetOwnerGlobal() const override {

    return mParentObject;

  }

  bool HasOrHasHadOwner() { return mHasOrHasHadOwnerWindow; }

  virtual void EventListenerAdded(nsAtom* aType) override;

  virtual void EventListenerAdded(const nsAString& aType) override;

  virtual void EventListenerRemoved(nsAtom* aType) override;

  virtual void EventListenerRemoved(const nsAString& aType) override;

  virtual void EventListenerWasAdded(const nsAString& aType, ErrorResult& aRv,

                                     JSCompartment* aCompartment = nullptr) {}

  virtual void EventListenerWasRemoved(const nsAString& aType, ErrorResult& aRv,

                                       JSCompartment* aCompartment = nullptr) {}

  // Dispatch a trusted, non-cancellable and non-bubbling event to |this|.

  nsresult DispatchTrustedEvent(const nsAString& aEventName);

 protected:

  virtual ~DOMEventTargetHelper();

  nsresult WantsUntrusted(bool* aRetVal);

  void MaybeUpdateKeepAlive();

  void MaybeDontKeepAlive();

  // If this method returns true your object is kept alive until it returns

  // false. You can use this method instead using

  // NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN macro.

  virtual bool IsCertainlyAliveForCC() const { return mIsKeptAlive; }

  RefPtr<EventListenerManager> mListenerManager;

  // Make |event| trusted and dispatch |aEvent| to |this|.

  nsresult DispatchTrustedEvent(nsIDOMEvent* aEvent);

  virtual void LastRelease() {}

  void KeepAliveIfHasListenersFor(const nsAString& aType);

  void KeepAliveIfHasListenersFor(nsAtom* aType);

  void IgnoreKeepAliveIfHasListenersFor(const nsAString& aType);

  void IgnoreKeepAliveIfHasListenersFor(nsAtom* aType);

 private:

  // The parent global object.  The global will clear this when

  // it is destroyed by calling DisconnectFromOwner().

  nsIGlobalObject* MOZ_NON_OWNING_REF mParentObject;

  // mParentObject pre QI-ed and cached (inner window)

  // (it is needed for off main thread access)

  // It is obtained in BindToOwner and reset in DisconnectFromOwner.

  nsPIDOMWindowInner* MOZ_NON_OWNING_REF mOwnerWindow;

  bool mHasOrHasHadOwnerWindow;

  struct {

    nsTArray<nsString> mStrings;

    nsTArray<RefPtr<nsAtom>> mAtoms;

  } mKeepingAliveTypes;

  bool mIsKeptAlive;

};

NS_DEFINE_STATIC_IID_ACCESSOR(DOMEventTargetHelper, NS_DOMEVENTTARGETHELPER_IID)

}  // namespace mozilla

// WebIDL event handlers

#define IMPL_EVENT_HANDLER(_event)                                          \

  inline mozilla::dom::EventHandlerNonNull* GetOn##_event() {               \

    if (NS_IsMainThread()) {                                                \

      return GetEventHandler(nsGkAtoms::on##_event, EmptyString());         \

    }                                                                       \

    return GetEventHandler(nullptr, NS_LITERAL_STRING(#_event));            \

  }                                                                         \

  inline void SetOn##_event(mozilla::dom::EventHandlerNonNull* aCallback) { \

    if (NS_IsMainThread()) {                                                \

      SetEventHandler(nsGkAtoms::on##_event, EmptyString(), aCallback);     \

    } else {                                                                \

      SetEventHandler(nullptr, NS_LITERAL_STRING(#_event), aCallback);      \

    }                                                                       \

  }

/* Use this macro to declare functions that forward the behavior of this

 * interface to another object.

 * This macro doesn't forward GetEventTargetParent because sometimes subclasses

 * want to override it.

 */

#define NS_FORWARD_NSIDOMEVENTTARGET_NOGETEVENTTARGETPARENT(_to)               \

  NS_IMETHOD AddEventListener(const nsAString& type,                           \

                              nsIDOMEventListener* listener, bool useCapture,  \

                              bool wantsUntrusted, uint8_t _argc) override {   \

    return _to AddEventListener(type, listener, useCapture, wantsUntrusted,    \

                                _argc);                                        \

  }                                                                            \

  NS_IMETHOD AddSystemEventListener(                                           \

      const nsAString& type, nsIDOMEventListener* listener, bool aUseCapture,  \

      bool aWantsUntrusted, uint8_t _argc) override {                          \

    return _to AddSystemEventListener(type, listener, aUseCapture,             \

                                      aWantsUntrusted, _argc);                 \

  }                                                                            \

  NS_IMETHOD RemoveEventListener(                                              \

      const nsAString& type, nsIDOMEventListener* listener, bool useCapture)   \

      override {                                                               \

    return _to RemoveEventListener(type, listener, useCapture);                \

  }                                                                            \

  NS_IMETHOD RemoveSystemEventListener(                                        \

      const nsAString& type, nsIDOMEventListener* listener, bool aUseCapture)  \

      override {                                                               \

    return _to RemoveSystemEventListener(type, listener, aUseCapture);         \

  }                                                                            \

  NS_IMETHOD DispatchEvent(nsIDOMEvent* evt, bool* _retval) override {         \

    return _to DispatchEvent(evt, _retval);                                    \

  }                                                                            \

  virtual mozilla::dom::EventTarget* GetTargetForDOMEvent() {                  \

    return _to GetTargetForDOMEvent();                                         \

  }                                                                            \

  virtual mozilla::dom::EventTarget* GetTargetForEventTargetChain() {          \

    return _to GetTargetForEventTargetChain();                                 \

  }                                                                            \

  virtual nsresult WillHandleEvent(mozilla::EventChainPostVisitor& aVisitor) { \

    return _to WillHandleEvent(aVisitor);                                      \

  }                                                                            \

  virtual nsresult PostHandleEvent(mozilla::EventChainPostVisitor& aVisitor) { \

    return _to PostHandleEvent(aVisitor);                                      \

  }                                                                            \

  virtual nsresult DispatchDOMEvent(                                           \

      mozilla::WidgetEvent* aEvent, nsIDOMEvent* aDOMEvent,                    \

      nsPresContext* aPresContext, nsEventStatus* aEventStatus) {              \

    return _to DispatchDOMEvent(aEvent, aDOMEvent, aPresContext,               \

                                aEventStatus);                                 \

  }                                                                            \

  virtual mozilla::EventListenerManager* GetOrCreateListenerManager() {        \

    return _to GetOrCreateListenerManager();                                   \

  }                                                                            \

  virtual mozilla::EventListenerManager* GetExistingListenerManager() const {  \

    return _to GetExistingListenerManager();                                   \

  }                                                                            \

  virtual nsIScriptContext* GetContextForEventHandlers(nsresult* aRv) {        \

    return _to GetContextForEventHandlers(aRv);                                \

  }

#define NS_REALLY_FORWARD_NSIDOMEVENTTARGET(_class)                   \

  using _class::AddEventListener;                                     \

  using _class::RemoveEventListener;                                  \

  NS_FORWARD_NSIDOMEVENTTARGET(_class::)                              \

  virtual mozilla::EventListenerManager* GetOrCreateListenerManager() \

      override {                                                      \

    return _class::GetOrCreateListenerManager();                      \

  }                                                                   \

  virtual mozilla::EventListenerManager* GetExistingListenerManager() \

      const override {                                                \

    return _class::GetExistingListenerManager();                      \

  }

#endif  // mozilla_DOMEventTargetHelper_h_