/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-

 *

 * 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_image_imgRequestProxy_h

#define mozilla_image_imgRequestProxy_h

#include "imgIRequest.h"

#include "nsILoadGroup.h"

#include "nsISupportsPriority.h"

#include "nsITimedChannel.h"

#include "nsCOMPtr.h"

#include "nsThreadUtils.h"

#include "mozilla/TimeStamp.h"

#include "mozilla/UniquePtr.h"

#include "mozilla/gfx/Rect.h"

#include "imgRequest.h"

#include "IProgressObserver.h"

#define NS_IMGREQUESTPROXY_CID \

{ /* 20557898-1dd2-11b2-8f65-9c462ee2bc95 */         \

     0x20557898,                                     \

     0x1dd2,                                         \

     0x11b2,                                         \

    {0x8f, 0x65, 0x9c, 0x46, 0x2e, 0xe2, 0xbc, 0x95} \

}

class imgCacheValidator;

class imgINotificationObserver;

class imgStatusNotifyRunnable;

class ProxyBehaviour;

namespace mozilla {

namespace dom {

class TabGroup;

}

namespace image {

class Image;

class ProgressTracker;

} // namespace image

} // namespace mozilla

class imgRequestProxy : public imgIRequest,

                        public mozilla::image::IProgressObserver,

                        public nsISupportsPriority,

                        public nsITimedChannel

{

protected:

  virtual ~imgRequestProxy();

public:

  typedef mozilla::image::Image Image;

  typedef mozilla::image::ProgressTracker ProgressTracker;

  MOZ_DECLARE_REFCOUNTED_TYPENAME(imgRequestProxy)

  NS_DECL_ISUPPORTS

  NS_DECL_IMGIREQUEST

  NS_DECL_NSIREQUEST

  NS_DECL_NSISUPPORTSPRIORITY

  // nsITimedChannel declared below

  imgRequestProxy();

  // Callers to Init or ChangeOwner are required to call NotifyListener after

  // (although not immediately after) doing so.

  nsresult Init(imgRequest* aOwner,

                nsILoadGroup* aLoadGroup,

                nsIDocument* aLoadingDocument,

                nsIURI* aURI,

                imgINotificationObserver* aObserver);

  nsresult ChangeOwner(imgRequest* aNewOwner); // this will change mOwner.

                                               // Do not call this if the

                                               // previous owner has already

                                               // sent notifications out!

  // Add the request to the load group, if any. This should only be called once

  // during initialization.

  void AddToLoadGroup();

  inline bool HasObserver() const {

    return mListener != nullptr;

  }

  // Asynchronously notify this proxy's listener of the current state of the

  // image, and, if we have an imgRequest mOwner, any status changes that

  // happen between the time this function is called and the time the

  // notification is scheduled.

  void NotifyListener();

  // Synchronously notify this proxy's listener of the current state of the

  // image. Only use this function if you are currently servicing an

  // asynchronously-called function.

  void SyncNotifyListener();

  // imgINotificationObserver methods:

  virtual void Notify(int32_t aType,

                      const mozilla::gfx::IntRect* aRect = nullptr) override;

  virtual void OnLoadComplete(bool aLastPart) override;

  // Other, internal-only methods:

  virtual void SetHasImage() override;

  // Whether we want notifications from ProgressTracker to be deferred until

  // an event it has scheduled has been fired and/or validation is complete.

  virtual bool NotificationsDeferred() const override

  {

    return IsValidating() || mPendingNotify;

  }

  virtual void MarkPendingNotify() override

  {

    mPendingNotify = true;

  }

  virtual void ClearPendingNotify() override

  {

    mPendingNotify = false;

  }

  bool IsValidating() const

  {

    return mValidating;

  }

  void MarkValidating();

  void ClearValidating();

  bool IsOnEventTarget() const;

  already_AddRefed<nsIEventTarget> GetEventTarget() const override;

  // Removes all animation consumers that were created with

  // IncrementAnimationConsumers. This is necessary since we need

  // to do it before the proxy itself is destroyed. See

  // imgRequest::RemoveProxy

  void ClearAnimationConsumers();

  nsresult SyncClone(imgINotificationObserver* aObserver,

                     nsIDocument* aLoadingDocument,

                     imgRequestProxy** aClone);

  nsresult Clone(imgINotificationObserver* aObserver,

                 nsIDocument* aLoadingDocument,

                 imgRequestProxy** aClone);

  nsresult GetStaticRequest(nsIDocument* aLoadingDocument,

                            imgRequestProxy** aReturn);

protected:

  friend class mozilla::image::ProgressTracker;

  friend class imgStatusNotifyRunnable;

  class imgCancelRunnable;

  friend class imgCancelRunnable;

  class imgCancelRunnable : public mozilla::Runnable

  {

    public:

      imgCancelRunnable(imgRequestProxy* owner, nsresult status)

        : Runnable("imgCancelRunnable"), mOwner(owner), mStatus(status)

      { }

      NS_IMETHOD Run() override {

        mOwner->DoCancel(mStatus);

        return NS_OK;

      }

    private:

      RefPtr<imgRequestProxy> mOwner;

      nsresult mStatus;

  };

  /* Remove from and forget the load group. */

  void RemoveFromLoadGroup();

  /* Remove from the load group and readd as a background request. */

  void MoveToBackgroundInLoadGroup();

  /* Finish up canceling ourselves */

  void DoCancel(nsresult status);

  /* Do the proper refcount management to null out mListener */

  void NullOutListener();

  // Return the ProgressTracker associated with mOwner and/or mImage. It may

  // live either on mOwner or mImage, depending on whether

  //   (a) we have an mOwner at all

  //   (b) whether mOwner has instantiated its image yet

  already_AddRefed<ProgressTracker> GetProgressTracker() const;

  nsITimedChannel* TimedChannel()

  {

    if (!GetOwner()) {

      return nullptr;

    }

    return GetOwner()->GetTimedChannel();

  }

  already_AddRefed<Image> GetImage() const;

  bool HasImage() const;

  imgRequest* GetOwner() const;

  imgCacheValidator* GetValidator() const;

  nsresult PerformClone(imgINotificationObserver* aObserver,

                        nsIDocument* aLoadingDocument,

                        bool aSyncNotify,

                        imgRequestProxy** aClone);

  virtual imgRequestProxy* NewClonedProxy();

public:

  NS_FORWARD_SAFE_NSITIMEDCHANNEL(TimedChannel())

protected:

  mozilla::UniquePtr<ProxyBehaviour> mBehaviour;

private:

  friend class imgCacheValidator;

  void AddToOwner(nsIDocument* aLoadingDocument);

  void RemoveFromOwner(nsresult aStatus);

  nsresult DispatchWithTargetIfAvailable(already_AddRefed<nsIRunnable> aEvent);

  void DispatchWithTarget(already_AddRefed<nsIRunnable> aEvent);

  // The URI of our request.

  nsCOMPtr<nsIURI> mURI;

  // mListener is only promised to be a weak ref (see imgILoader.idl),

  // but we actually keep a strong ref to it until we've seen our

  // first OnStopRequest.

  imgINotificationObserver* MOZ_UNSAFE_REF("Observers must call Cancel() or "

                                           "CancelAndForgetObserver() before "

                                           "they are destroyed") mListener;

  nsCOMPtr<nsILoadGroup> mLoadGroup;

  RefPtr<mozilla::dom::TabGroup> mTabGroup;

  nsCOMPtr<nsIEventTarget> mEventTarget;

  nsLoadFlags mLoadFlags;

  uint32_t    mLockCount;

  uint32_t    mAnimationConsumers;

  bool mCanceled : 1;

  bool mIsInLoadGroup : 1;

  bool mForceDispatchLoadGroup : 1;

  bool mListenerIsStrongRef : 1;

  bool mDecodeRequested : 1;

  // Whether we want to defer our notifications by the non-virtual Observer

  // interfaces as image loads proceed.

  bool mPendingNotify : 1;

  bool mValidating : 1;

  bool mHadListener : 1;

  bool mHadDispatch : 1;

};

// Used for static image proxies for which no requests are available, so

// certain behaviours must be overridden to compensate.

class imgRequestProxyStatic : public imgRequestProxy

{

public:

  imgRequestProxyStatic(Image* aImage, nsIPrincipal* aPrincipal);

  NS_IMETHOD GetImagePrincipal(nsIPrincipal** aPrincipal) override;

protected:

  imgRequestProxy* NewClonedProxy() override;

  // Our principal. We have to cache it, rather than accessing the underlying

  // request on-demand, because static proxies don't have an underlying request.

  nsCOMPtr<nsIPrincipal> mPrincipal;

};

#endif // mozilla_image_imgRequestProxy_h