image/VectorImage.cpp
author Andrew Osmond <aosmond@mozilla.com>
Mon, 17 Dec 2018 08:31:04 -0500
changeset 511111 325d06d3ba7341035f01ae14bc882643d0235083
parent 509549 f0a91d36587266d7454a450c6044d573664fbed5
child 511112 b709624ce8fa0ca4146d8d0675036440e6807615
permissions -rw-r--r--
Bug 1510139 - Part 1. Ensure we honor invalidations if using vector image containers. r=tnikkel If a vector image has an image container, it is unlikely the caller will call VectorImage::Draw (and thus Show indirectly) to display the image. As such, WebRender was missing subsequent invalidations and not regenerating the rasterized surface as expected. Thus we now resume honoring the invalidations if we updated the image container. Differential Revision: https://phabricator.services.mozilla.com/D15667

/* -*- 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/. */

#include "VectorImage.h"

#include "gfx2DGlue.h"
#include "gfxContext.h"
#include "gfxDrawable.h"
#include "gfxPlatform.h"
#include "gfxUtils.h"
#include "imgFrame.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/SVGSVGElement.h"
#include "mozilla/dom/SVGDocument.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/PendingAnimationTracker.h"
#include "mozilla/RefPtr.h"
#include "mozilla/Tuple.h"
#include "nsIPresShell.h"
#include "nsIStreamListener.h"
#include "nsMimeTypes.h"
#include "nsPresContext.h"
#include "nsRect.h"
#include "nsString.h"
#include "nsStubDocumentObserver.h"
#include "SVGObserverUtils.h"  // for SVGRenderingObserver
#include "nsWindowSizes.h"
#include "ImageRegion.h"
#include "ISurfaceProvider.h"
#include "LookupResult.h"
#include "Orientation.h"
#include "SVGDocumentWrapper.h"
#include "SVGDrawingParameters.h"
#include "nsIDOMEventListener.h"
#include "SurfaceCache.h"
#include "mozilla/dom/Document.h"

namespace mozilla {

using namespace dom;
using namespace dom::SVGPreserveAspectRatio_Binding;
using namespace gfx;
using namespace layers;

namespace image {

// Helper-class: SVGRootRenderingObserver
class SVGRootRenderingObserver final : public SVGRenderingObserver {
 public:
  NS_DECL_ISUPPORTS

  SVGRootRenderingObserver(SVGDocumentWrapper* aDocWrapper,
                           VectorImage* aVectorImage)
      : SVGRenderingObserver(),
        mDocWrapper(aDocWrapper),
        mVectorImage(aVectorImage),
        mHonoringInvalidations(true) {
    MOZ_ASSERT(mDocWrapper, "Need a non-null SVG document wrapper");
    MOZ_ASSERT(mVectorImage, "Need a non-null VectorImage");

    StartObserving();
    Element* elem = GetReferencedElementWithoutObserving();
    MOZ_ASSERT(elem, "no root SVG node for us to observe");

    SVGObserverUtils::AddRenderingObserver(elem, this);
    mInObserverList = true;
  }

  void ResumeHonoringInvalidations() { mHonoringInvalidations = true; }

 protected:
  virtual ~SVGRootRenderingObserver() {
    // This needs to call our GetReferencedElementWithoutObserving override,
    // so must be called here rather than in our base class's dtor.
    StopObserving();
  }

  Element* GetReferencedElementWithoutObserving() final {
    return mDocWrapper->GetRootSVGElem();
  }

  virtual void OnRenderingChange() override {
    Element* elem = GetReferencedElementWithoutObserving();
    MOZ_ASSERT(elem, "missing root SVG node");

    if (mHonoringInvalidations && !mDocWrapper->ShouldIgnoreInvalidation()) {
      nsIFrame* frame = elem->GetPrimaryFrame();
      if (!frame || frame->PresShell()->IsDestroying()) {
        // We're being destroyed. Bail out.
        return;
      }

      // Ignore further invalidations until we draw.
      mHonoringInvalidations = false;

      mVectorImage->InvalidateObserversOnNextRefreshDriverTick();
    }

    // Our caller might've removed us from rendering-observer list.
    // Add ourselves back!
    if (!mInObserverList) {
      SVGObserverUtils::AddRenderingObserver(elem, this);
      mInObserverList = true;
    }
  }

  // Private data
  const RefPtr<SVGDocumentWrapper> mDocWrapper;
  VectorImage* const mVectorImage;  // Raw pointer because it owns me.
  bool mHonoringInvalidations;
};

NS_IMPL_ISUPPORTS(SVGRootRenderingObserver, nsIMutationObserver)

class SVGParseCompleteListener final : public nsStubDocumentObserver {
 public:
  NS_DECL_ISUPPORTS

  SVGParseCompleteListener(SVGDocument* aDocument, VectorImage* aImage)
      : mDocument(aDocument), mImage(aImage) {
    MOZ_ASSERT(mDocument, "Need an SVG document");
    MOZ_ASSERT(mImage, "Need an image");

    mDocument->AddObserver(this);
  }

 private:
  ~SVGParseCompleteListener() {
    if (mDocument) {
      // The document must have been destroyed before we got our event.
      // Otherwise this can't happen, since documents hold strong references to
      // their observers.
      Cancel();
    }
  }

 public:
  void EndLoad(Document* aDocument) override {
    MOZ_ASSERT(aDocument == mDocument, "Got EndLoad for wrong document?");

    // OnSVGDocumentParsed will release our owner's reference to us, so ensure
    // we stick around long enough to complete our work.
    RefPtr<SVGParseCompleteListener> kungFuDeathGrip(this);

    mImage->OnSVGDocumentParsed();
  }

  void Cancel() {
    MOZ_ASSERT(mDocument, "Duplicate call to Cancel");
    if (mDocument) {
      mDocument->RemoveObserver(this);
      mDocument = nullptr;
    }
  }

 private:
  RefPtr<SVGDocument> mDocument;
  VectorImage* const mImage;  // Raw pointer to owner.
};

NS_IMPL_ISUPPORTS(SVGParseCompleteListener, nsIDocumentObserver)

class SVGLoadEventListener final : public nsIDOMEventListener {
 public:
  NS_DECL_ISUPPORTS

  SVGLoadEventListener(Document* aDocument, VectorImage* aImage)
      : mDocument(aDocument), mImage(aImage) {
    MOZ_ASSERT(mDocument, "Need an SVG document");
    MOZ_ASSERT(mImage, "Need an image");

    mDocument->AddEventListener(NS_LITERAL_STRING("MozSVGAsImageDocumentLoad"),
                                this, true, false);
    mDocument->AddEventListener(NS_LITERAL_STRING("SVGAbort"), this, true,
                                false);
    mDocument->AddEventListener(NS_LITERAL_STRING("SVGError"), this, true,
                                false);
  }

 private:
  ~SVGLoadEventListener() {
    if (mDocument) {
      // The document must have been destroyed before we got our event.
      // Otherwise this can't happen, since documents hold strong references to
      // their observers.
      Cancel();
    }
  }

 public:
  NS_IMETHOD HandleEvent(Event* aEvent) override {
    MOZ_ASSERT(mDocument, "Need an SVG document. Received multiple events?");

    // OnSVGDocumentLoaded/OnSVGDocumentError will release our owner's reference
    // to us, so ensure we stick around long enough to complete our work.
    RefPtr<SVGLoadEventListener> kungFuDeathGrip(this);

    nsAutoString eventType;
    aEvent->GetType(eventType);
    MOZ_ASSERT(eventType.EqualsLiteral("MozSVGAsImageDocumentLoad") ||
                   eventType.EqualsLiteral("SVGAbort") ||
                   eventType.EqualsLiteral("SVGError"),
               "Received unexpected event");

    if (eventType.EqualsLiteral("MozSVGAsImageDocumentLoad")) {
      mImage->OnSVGDocumentLoaded();
    } else {
      mImage->OnSVGDocumentError();
    }

    return NS_OK;
  }

  void Cancel() {
    MOZ_ASSERT(mDocument, "Duplicate call to Cancel");
    if (mDocument) {
      mDocument->RemoveEventListener(
          NS_LITERAL_STRING("MozSVGAsImageDocumentLoad"), this, true);
      mDocument->RemoveEventListener(NS_LITERAL_STRING("SVGAbort"), this, true);
      mDocument->RemoveEventListener(NS_LITERAL_STRING("SVGError"), this, true);
      mDocument = nullptr;
    }
  }

 private:
  nsCOMPtr<Document> mDocument;
  VectorImage* const mImage;  // Raw pointer to owner.
};

NS_IMPL_ISUPPORTS(SVGLoadEventListener, nsIDOMEventListener)

// Helper-class: SVGDrawingCallback
class SVGDrawingCallback : public gfxDrawingCallback {
 public:
  SVGDrawingCallback(SVGDocumentWrapper* aSVGDocumentWrapper,
                     const IntSize& aViewportSize, const IntSize& aSize,
                     uint32_t aImageFlags)
      : mSVGDocumentWrapper(aSVGDocumentWrapper),
        mViewportSize(aViewportSize),
        mSize(aSize),
        mImageFlags(aImageFlags) {}
  virtual bool operator()(gfxContext* aContext, const gfxRect& aFillRect,
                          const SamplingFilter aSamplingFilter,
                          const gfxMatrix& aTransform) override;

 private:
  RefPtr<SVGDocumentWrapper> mSVGDocumentWrapper;
  const IntSize mViewportSize;
  const IntSize mSize;
  uint32_t mImageFlags;
};

// Based loosely on nsSVGIntegrationUtils' PaintFrameCallback::operator()
bool SVGDrawingCallback::operator()(gfxContext* aContext,
                                    const gfxRect& aFillRect,
                                    const SamplingFilter aSamplingFilter,
                                    const gfxMatrix& aTransform) {
  MOZ_ASSERT(mSVGDocumentWrapper, "need an SVGDocumentWrapper");

  // Get (& sanity-check) the helper-doc's presShell
  nsCOMPtr<nsIPresShell> presShell = mSVGDocumentWrapper->GetPresShell();
  MOZ_ASSERT(presShell, "GetPresShell returned null for an SVG image?");

#ifdef MOZ_GECKO_PROFILER
  Document* doc = presShell->GetDocument();
  nsIURI* uri = doc ? doc->GetDocumentURI() : nullptr;
  AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING(
      "SVG Image drawing", GRAPHICS,
      nsPrintfCString("%dx%d %s", mSize.width, mSize.height,
                      uri ? uri->GetSpecOrDefault().get() : "N/A"));
#endif

  gfxContextAutoSaveRestore contextRestorer(aContext);

  // Clip to aFillRect so that we don't paint outside.
  aContext->NewPath();
  aContext->Rectangle(aFillRect);
  aContext->Clip();

  gfxMatrix matrix = aTransform;
  if (!matrix.Invert()) {
    return false;
  }
  aContext->SetMatrixDouble(
      aContext->CurrentMatrixDouble().PreMultiply(matrix).PreScale(
          double(mSize.width) / mViewportSize.width,
          double(mSize.height) / mViewportSize.height));

  nsPresContext* presContext = presShell->GetPresContext();
  MOZ_ASSERT(presContext, "pres shell w/out pres context");

  nsRect svgRect(0, 0, presContext->DevPixelsToAppUnits(mViewportSize.width),
                 presContext->DevPixelsToAppUnits(mViewportSize.height));

  uint32_t renderDocFlags = nsIPresShell::RENDER_IGNORE_VIEWPORT_SCROLLING;
  if (!(mImageFlags & imgIContainer::FLAG_SYNC_DECODE)) {
    renderDocFlags |= nsIPresShell::RENDER_ASYNC_DECODE_IMAGES;
  }

  presShell->RenderDocument(svgRect, renderDocFlags,
                            NS_RGBA(0, 0, 0, 0),  // transparent
                            aContext);

  return true;
}

class MOZ_STACK_CLASS AutoRestoreSVGState final {
 public:
  AutoRestoreSVGState(const SVGDrawingParameters& aParams,
                      SVGDocumentWrapper* aSVGDocumentWrapper, bool& aIsDrawing,
                      bool aContextPaint)
      : mIsDrawing(aIsDrawing)
        // Apply any 'preserveAspectRatio' override (if specified) to the root
        // element:
        ,
        mPAR(aParams.svgContext, aSVGDocumentWrapper->GetRootSVGElem())
        // Set the animation time:
        ,
        mTime(aSVGDocumentWrapper->GetRootSVGElem(), aParams.animationTime) {
    MOZ_ASSERT(!aIsDrawing);
    MOZ_ASSERT(aSVGDocumentWrapper->GetDocument());

    aIsDrawing = true;

    // Set context paint (if specified) on the document:
    if (aContextPaint) {
      MOZ_ASSERT(aParams.svgContext->GetContextPaint());
      mContextPaint.emplace(*aParams.svgContext->GetContextPaint(),
                            *aSVGDocumentWrapper->GetDocument());
    }
  }

 private:
  AutoRestore<bool> mIsDrawing;
  AutoPreserveAspectRatioOverride mPAR;
  AutoSVGTimeSetRestore mTime;
  Maybe<AutoSetRestoreSVGContextPaint> mContextPaint;
};

// Implement VectorImage's nsISupports-inherited methods
NS_IMPL_ISUPPORTS(VectorImage, imgIContainer, nsIStreamListener,
                  nsIRequestObserver)

//------------------------------------------------------------------------------
// Constructor / Destructor

VectorImage::VectorImage(nsIURI* aURI /* = nullptr */)
    : ImageResource(aURI),  // invoke superclass's constructor
      mLockCount(0),
      mIsInitialized(false),
      mDiscardable(false),
      mIsFullyLoaded(false),
      mIsDrawing(false),
      mHaveAnimations(false),
      mHasPendingInvalidation(false) {}

VectorImage::~VectorImage() {
  CancelAllListeners();
  SurfaceCache::RemoveImage(ImageKey(this));
}

//------------------------------------------------------------------------------
// Methods inherited from Image.h

nsresult VectorImage::Init(const char* aMimeType, uint32_t aFlags) {
  // We don't support re-initialization
  if (mIsInitialized) {
    return NS_ERROR_ILLEGAL_VALUE;
  }

  MOZ_ASSERT(!mIsFullyLoaded && !mHaveAnimations && !mError,
             "Flags unexpectedly set before initialization");
  MOZ_ASSERT(!strcmp(aMimeType, IMAGE_SVG_XML), "Unexpected mimetype");

  mDiscardable = !!(aFlags & INIT_FLAG_DISCARDABLE);

  // Lock this image's surfaces in the SurfaceCache if we're not discardable.
  if (!mDiscardable) {
    mLockCount++;
    SurfaceCache::LockImage(ImageKey(this));
  }

  mIsInitialized = true;
  return NS_OK;
}

size_t VectorImage::SizeOfSourceWithComputedFallback(
    SizeOfState& aState) const {
  if (!mSVGDocumentWrapper) {
    return 0;  // No document, so no memory used for the document.
  }

  SVGDocument* doc = mSVGDocumentWrapper->GetDocument();
  if (!doc) {
    return 0;  // No document, so no memory used for the document.
  }

  nsWindowSizes windowSizes(aState);
  doc->DocAddSizeOfIncludingThis(windowSizes);

  if (windowSizes.getTotalSize() == 0) {
    // MallocSizeOf fails on this platform. Because we also use this method for
    // determining the size of cache entries, we need to return something
    // reasonable here. Unfortunately, there's no way to estimate the document's
    // size accurately, so we just use a constant value of 100KB, which will
    // generally underestimate the true size.
    return 100 * 1024;
  }

  return windowSizes.getTotalSize();
}

void VectorImage::CollectSizeOfSurfaces(
    nsTArray<SurfaceMemoryCounter>& aCounters,
    MallocSizeOf aMallocSizeOf) const {
  SurfaceCache::CollectSizeOfSurfaces(ImageKey(this), aCounters, aMallocSizeOf);
}

nsresult VectorImage::OnImageDataComplete(nsIRequest* aRequest,
                                          nsISupports* aContext,
                                          nsresult aStatus, bool aLastPart) {
  // Call our internal OnStopRequest method, which only talks to our embedded
  // SVG document. This won't have any effect on our ProgressTracker.
  nsresult finalStatus = OnStopRequest(aRequest, aContext, aStatus);

  // Give precedence to Necko failure codes.
  if (NS_FAILED(aStatus)) {
    finalStatus = aStatus;
  }

  Progress loadProgress = LoadCompleteProgress(aLastPart, mError, finalStatus);

  if (mIsFullyLoaded || mError) {
    // Our document is loaded, so we're ready to notify now.
    mProgressTracker->SyncNotifyProgress(loadProgress);
  } else {
    // Record our progress so far; we'll actually send the notifications in
    // OnSVGDocumentLoaded or OnSVGDocumentError.
    mLoadProgress = Some(loadProgress);
  }

  return finalStatus;
}

nsresult VectorImage::OnImageDataAvailable(nsIRequest* aRequest,
                                           nsISupports* aContext,
                                           nsIInputStream* aInStr,
                                           uint64_t aSourceOffset,
                                           uint32_t aCount) {
  return OnDataAvailable(aRequest, aContext, aInStr, aSourceOffset, aCount);
}

nsresult VectorImage::StartAnimation() {
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  MOZ_ASSERT(ShouldAnimate(), "Should not animate!");

  mSVGDocumentWrapper->StartAnimation();
  return NS_OK;
}

nsresult VectorImage::StopAnimation() {
  nsresult rv = NS_OK;
  if (mError) {
    rv = NS_ERROR_FAILURE;
  } else {
    MOZ_ASSERT(mIsFullyLoaded && mHaveAnimations,
               "Should not have been animating!");

    mSVGDocumentWrapper->StopAnimation();
  }

  mAnimating = false;
  return rv;
}

bool VectorImage::ShouldAnimate() {
  return ImageResource::ShouldAnimate() && mIsFullyLoaded && mHaveAnimations;
}

NS_IMETHODIMP_(void)
VectorImage::SetAnimationStartTime(const TimeStamp& aTime) {
  // We don't care about animation start time.
}

//------------------------------------------------------------------------------
// imgIContainer methods

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetWidth(int32_t* aWidth) {
  if (mError || !mIsFullyLoaded) {
    // XXXdholbert Technically we should leave outparam untouched when we
    // fail. But since many callers don't check for failure, we set it to 0 on
    // failure, for sane/predictable results.
    *aWidth = 0;
    return NS_ERROR_FAILURE;
  }

  SVGSVGElement* rootElem = mSVGDocumentWrapper->GetRootSVGElem();
  MOZ_ASSERT(rootElem,
             "Should have a root SVG elem, since we finished "
             "loading without errors");
  int32_t rootElemWidth = rootElem->GetIntrinsicWidth();
  if (rootElemWidth < 0) {
    *aWidth = 0;
    return NS_ERROR_FAILURE;
  }
  *aWidth = rootElemWidth;
  return NS_OK;
}

//******************************************************************************
nsresult VectorImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const {
  return NS_ERROR_NOT_IMPLEMENTED;
}

//******************************************************************************
size_t VectorImage::GetNativeSizesLength() const { return 0; }

//******************************************************************************
NS_IMETHODIMP_(void)
VectorImage::RequestRefresh(const TimeStamp& aTime) {
  if (HadRecentRefresh(aTime)) {
    return;
  }

  PendingAnimationTracker* tracker =
      mSVGDocumentWrapper->GetDocument()->GetPendingAnimationTracker();
  if (tracker && ShouldAnimate()) {
    tracker->TriggerPendingAnimationsOnNextTick(aTime);
  }

  EvaluateAnimation();

  mSVGDocumentWrapper->TickRefreshDriver();

  if (mHasPendingInvalidation) {
    mHasPendingInvalidation = false;
    SendInvalidationNotifications();
  }
}

void VectorImage::SendInvalidationNotifications() {
  // Animated images don't send out invalidation notifications as soon as
  // they're generated. Instead, InvalidateObserversOnNextRefreshDriverTick
  // records that there are pending invalidations and then returns immediately.
  // The notifications are actually sent from RequestRefresh(). We send these
  // notifications there to ensure that there is actually a document observing
  // us. Otherwise, the notifications are just wasted effort.
  //
  // Non-animated images call this method directly from
  // InvalidateObserversOnNextRefreshDriverTick, because RequestRefresh is never
  // called for them. Ordinarily this isn't needed, since we send out
  // invalidation notifications in OnSVGDocumentLoaded, but in rare cases the
  // SVG document may not be 100% ready to render at that time. In those cases
  // we would miss the subsequent invalidations if we didn't send out the
  // notifications directly in |InvalidateObservers...|.

  SurfaceCache::RemoveImage(ImageKey(this));

  if (UpdateImageContainer(Nothing())) {
    // If we have image containers, that means we probably won't get a Draw call
    // from the owner since they are using the container. We must assume all
    // invalidations need to be handled.
    MOZ_ASSERT(mRenderingObserver, "Should have a rendering observer by now");
    mRenderingObserver->ResumeHonoringInvalidations();
  }

  if (mProgressTracker) {
    mProgressTracker->SyncNotifyProgress(FLAG_FRAME_COMPLETE,
                                         GetMaxSizedIntRect());
  }
}

NS_IMETHODIMP_(IntRect)
VectorImage::GetImageSpaceInvalidationRect(const IntRect& aRect) {
  return aRect;
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetHeight(int32_t* aHeight) {
  if (mError || !mIsFullyLoaded) {
    // XXXdholbert Technically we should leave outparam untouched when we
    // fail. But since many callers don't check for failure, we set it to 0 on
    // failure, for sane/predictable results.
    *aHeight = 0;
    return NS_ERROR_FAILURE;
  }

  SVGSVGElement* rootElem = mSVGDocumentWrapper->GetRootSVGElem();
  MOZ_ASSERT(rootElem,
             "Should have a root SVG elem, since we finished "
             "loading without errors");
  int32_t rootElemHeight = rootElem->GetIntrinsicHeight();
  if (rootElemHeight < 0) {
    *aHeight = 0;
    return NS_ERROR_FAILURE;
  }
  *aHeight = rootElemHeight;
  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetIntrinsicSize(nsSize* aSize) {
  if (mError || !mIsFullyLoaded) {
    return NS_ERROR_FAILURE;
  }

  nsIFrame* rootFrame = mSVGDocumentWrapper->GetRootLayoutFrame();
  if (!rootFrame) {
    return NS_ERROR_FAILURE;
  }

  *aSize = nsSize(-1, -1);
  IntrinsicSize rfSize = rootFrame->GetIntrinsicSize();
  if (rfSize.width.GetUnit() == eStyleUnit_Coord) {
    aSize->width = rfSize.width.GetCoordValue();
  }
  if (rfSize.height.GetUnit() == eStyleUnit_Coord) {
    aSize->height = rfSize.height.GetCoordValue();
  }

  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetIntrinsicRatio(nsSize* aRatio) {
  if (mError || !mIsFullyLoaded) {
    return NS_ERROR_FAILURE;
  }

  nsIFrame* rootFrame = mSVGDocumentWrapper->GetRootLayoutFrame();
  if (!rootFrame) {
    return NS_ERROR_FAILURE;
  }

  *aRatio = rootFrame->GetIntrinsicRatio();
  return NS_OK;
}

NS_IMETHODIMP_(Orientation)
VectorImage::GetOrientation() { return Orientation(); }

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetType(uint16_t* aType) {
  NS_ENSURE_ARG_POINTER(aType);

  *aType = imgIContainer::TYPE_VECTOR;
  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::GetAnimated(bool* aAnimated) {
  if (mError || !mIsFullyLoaded) {
    return NS_ERROR_FAILURE;
  }

  *aAnimated = mSVGDocumentWrapper->IsAnimated();
  return NS_OK;
}

//******************************************************************************
int32_t VectorImage::GetFirstFrameDelay() {
  if (mError) {
    return -1;
  }

  if (!mSVGDocumentWrapper->IsAnimated()) {
    return -1;
  }

  // We don't really have a frame delay, so just pretend that we constantly
  // need updates.
  return 0;
}

NS_IMETHODIMP_(bool)
VectorImage::WillDrawOpaqueNow() {
  return false;  // In general, SVG content is not opaque.
}

//******************************************************************************
NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
VectorImage::GetFrame(uint32_t aWhichFrame, uint32_t aFlags) {
  if (mError) {
    return nullptr;
  }

  // Look up height & width
  // ----------------------
  SVGSVGElement* svgElem = mSVGDocumentWrapper->GetRootSVGElem();
  MOZ_ASSERT(svgElem,
             "Should have a root SVG elem, since we finished "
             "loading without errors");
  nsIntSize imageIntSize(svgElem->GetIntrinsicWidth(),
                         svgElem->GetIntrinsicHeight());

  if (imageIntSize.IsEmpty()) {
    // We'll get here if our SVG doc has a percent-valued or negative width or
    // height.
    return nullptr;
  }

  return GetFrameAtSize(imageIntSize, aWhichFrame, aFlags);
}

NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
VectorImage::GetFrameAtSize(const IntSize& aSize, uint32_t aWhichFrame,
                            uint32_t aFlags) {
#ifdef DEBUG
  NotifyDrawingObservers();
#endif

  auto result = GetFrameInternal(aSize, Nothing(), aWhichFrame, aFlags);
  return Get<2>(result).forget();
}

Tuple<ImgDrawResult, IntSize, RefPtr<SourceSurface>>
VectorImage::GetFrameInternal(const IntSize& aSize,
                              const Maybe<SVGImageContext>& aSVGContext,
                              uint32_t aWhichFrame, uint32_t aFlags) {
  MOZ_ASSERT(aWhichFrame <= FRAME_MAX_VALUE);

  if (aSize.IsEmpty() || aWhichFrame > FRAME_MAX_VALUE) {
    return MakeTuple(ImgDrawResult::BAD_ARGS, aSize, RefPtr<SourceSurface>());
  }

  if (mError) {
    return MakeTuple(ImgDrawResult::BAD_IMAGE, aSize, RefPtr<SourceSurface>());
  }

  if (!mIsFullyLoaded) {
    return MakeTuple(ImgDrawResult::NOT_READY, aSize, RefPtr<SourceSurface>());
  }

  // We don't allow large surfaces to be rasterized on the Draw and
  // GetImageContainerAtSize paths, because those have alternatives. If we get
  // here however, then we know it came from GetFrame(AtSize) and that path does
  // not have any fallback method, so we don't check UseSurfaceCacheForSize.
  RefPtr<SourceSurface> sourceSurface;
  IntSize decodeSize;
  Tie(sourceSurface, decodeSize) =
      LookupCachedSurface(aSize, aSVGContext, aFlags);
  if (sourceSurface) {
    return MakeTuple(ImgDrawResult::SUCCESS, decodeSize,
                     std::move(sourceSurface));
  }

  if (mIsDrawing) {
    NS_WARNING("Refusing to make re-entrant call to VectorImage::Draw");
    return MakeTuple(ImgDrawResult::TEMPORARY_ERROR, decodeSize,
                     RefPtr<SourceSurface>());
  }

  // By using a null gfxContext, we ensure that we will always attempt to
  // create a surface, even if we aren't capable of caching it (e.g. due to our
  // flags, having an animation, etc). Otherwise CreateSurface will assume that
  // the caller is capable of drawing directly to its own draw target if we
  // cannot cache.
  SVGDrawingParameters params(
      nullptr, decodeSize, aSize, ImageRegion::Create(decodeSize),
      SamplingFilter::POINT, aSVGContext,
      mSVGDocumentWrapper->GetCurrentTimeAsFloat(), aFlags, 1.0);

  bool didCache;  // Was the surface put into the cache?
  bool contextPaint = aSVGContext && aSVGContext->GetContextPaint();

  AutoRestoreSVGState autoRestore(params, mSVGDocumentWrapper, mIsDrawing,
                                  contextPaint);

  RefPtr<gfxDrawable> svgDrawable = CreateSVGDrawable(params);
  RefPtr<SourceSurface> surface = CreateSurface(params, svgDrawable, didCache);
  if (!surface) {
    MOZ_ASSERT(!didCache);
    return MakeTuple(ImgDrawResult::TEMPORARY_ERROR, decodeSize,
                     RefPtr<SourceSurface>());
  }

  SendFrameComplete(didCache, params.flags);
  return MakeTuple(ImgDrawResult::SUCCESS, decodeSize, std::move(surface));
}

//******************************************************************************
Tuple<ImgDrawResult, IntSize> VectorImage::GetImageContainerSize(
    LayerManager* aManager, const IntSize& aSize, uint32_t aFlags) {
  if (mError) {
    return MakeTuple(ImgDrawResult::BAD_IMAGE, IntSize(0, 0));
  }

  if (!mIsFullyLoaded) {
    return MakeTuple(ImgDrawResult::NOT_READY, IntSize(0, 0));
  }

  if (mHaveAnimations ||
      aManager->GetBackendType() != LayersBackend::LAYERS_WR) {
    return MakeTuple(ImgDrawResult::NOT_SUPPORTED, IntSize(0, 0));
  }

  // We don't need to check if the size is too big since we only support
  // WebRender backends.
  if (aSize.IsEmpty()) {
    return MakeTuple(ImgDrawResult::BAD_ARGS, IntSize(0, 0));
  }

  return MakeTuple(ImgDrawResult::SUCCESS, aSize);
}

NS_IMETHODIMP_(bool)
VectorImage::IsImageContainerAvailable(LayerManager* aManager,
                                       uint32_t aFlags) {
  if (mError || !mIsFullyLoaded || mHaveAnimations ||
      aManager->GetBackendType() != LayersBackend::LAYERS_WR) {
    return false;
  }

  return true;
}

//******************************************************************************
NS_IMETHODIMP_(already_AddRefed<ImageContainer>)
VectorImage::GetImageContainer(LayerManager* aManager, uint32_t aFlags) {
  MOZ_ASSERT(aManager->GetBackendType() != LayersBackend::LAYERS_WR,
             "WebRender should always use GetImageContainerAvailableAtSize!");
  return nullptr;
}

//******************************************************************************
NS_IMETHODIMP_(bool)
VectorImage::IsImageContainerAvailableAtSize(LayerManager* aManager,
                                             const IntSize& aSize,
                                             uint32_t aFlags) {
  // Since we only support image containers with WebRender, and it can handle
  // textures larger than the hw max texture size, we don't need to check aSize.
  return !aSize.IsEmpty() && UseSurfaceCacheForSize(aSize) &&
         IsImageContainerAvailable(aManager, aFlags);
}

//******************************************************************************
NS_IMETHODIMP_(ImgDrawResult)
VectorImage::GetImageContainerAtSize(layers::LayerManager* aManager,
                                     const gfx::IntSize& aSize,
                                     const Maybe<SVGImageContext>& aSVGContext,
                                     uint32_t aFlags,
                                     layers::ImageContainer** aOutContainer) {
  if (!UseSurfaceCacheForSize(aSize)) {
    return ImgDrawResult::NOT_SUPPORTED;
  }

  Maybe<SVGImageContext> newSVGContext;
  MaybeRestrictSVGContext(newSVGContext, aSVGContext, aFlags);

  // The aspect ratio flag was already handled as part of the SVG context
  // restriction above.
  uint32_t flags = aFlags & ~(FLAG_FORCE_PRESERVEASPECTRATIO_NONE);
  return GetImageContainerImpl(aManager, aSize,
                               newSVGContext ? newSVGContext : aSVGContext,
                               flags, aOutContainer);
}

bool VectorImage::MaybeRestrictSVGContext(
    Maybe<SVGImageContext>& aNewSVGContext,
    const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags) {
  bool overridePAR =
      (aFlags & FLAG_FORCE_PRESERVEASPECTRATIO_NONE) && aSVGContext;

  bool haveContextPaint = aSVGContext && aSVGContext->GetContextPaint();
  bool blockContextPaint = false;
  if (haveContextPaint) {
    blockContextPaint = !SVGContextPaint::IsAllowedForImageFromURI(mURI);
  }

  if (overridePAR || blockContextPaint) {
    // The key that we create for the image surface cache must match the way
    // that the image will be painted, so we need to initialize a new matching
    // SVGImageContext here in order to generate the correct key.

    aNewSVGContext = aSVGContext;  // copy

    if (overridePAR) {
      // The SVGImageContext must take account of the preserveAspectRatio
      // overide:
      MOZ_ASSERT(!aSVGContext->GetPreserveAspectRatio(),
                 "FLAG_FORCE_PRESERVEASPECTRATIO_NONE is not expected if a "
                 "preserveAspectRatio override is supplied");
      Maybe<SVGPreserveAspectRatio> aspectRatio = Some(SVGPreserveAspectRatio(
          SVG_PRESERVEASPECTRATIO_NONE, SVG_MEETORSLICE_UNKNOWN));
      aNewSVGContext->SetPreserveAspectRatio(aspectRatio);
    }

    if (blockContextPaint) {
      // The SVGImageContext must not include context paint if the image is
      // not allowed to use it:
      aNewSVGContext->ClearContextPaint();
    }
  }

  return haveContextPaint && !blockContextPaint;
}

//******************************************************************************
NS_IMETHODIMP_(ImgDrawResult)
VectorImage::Draw(gfxContext* aContext, const nsIntSize& aSize,
                  const ImageRegion& aRegion, uint32_t aWhichFrame,
                  SamplingFilter aSamplingFilter,
                  const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags,
                  float aOpacity) {
  if (aWhichFrame > FRAME_MAX_VALUE) {
    return ImgDrawResult::BAD_ARGS;
  }

  if (!aContext) {
    return ImgDrawResult::BAD_ARGS;
  }

  if (mError) {
    return ImgDrawResult::BAD_IMAGE;
  }

  if (!mIsFullyLoaded) {
    return ImgDrawResult::NOT_READY;
  }

  if (mAnimationConsumers == 0) {
    SendOnUnlockedDraw(aFlags);
  }

  // We should bypass the cache when:
  // - We are using a DrawTargetRecording because we prefer the drawing commands
  //   in general to the rasterized surface. This allows blob images to avoid
  //   rasterized SVGs with WebRender.
  // - The size exceeds what we are will to cache as a rasterized surface.
  if (aContext->GetDrawTarget()->GetBackendType() == BackendType::RECORDING ||
      !UseSurfaceCacheForSize(aSize)) {
    aFlags |= FLAG_BYPASS_SURFACE_CACHE;
  }

  MOZ_ASSERT(!(aFlags & FLAG_FORCE_PRESERVEASPECTRATIO_NONE) ||
                 (aSVGContext && aSVGContext->GetViewportSize()),
             "Viewport size is required when using "
             "FLAG_FORCE_PRESERVEASPECTRATIO_NONE");

  float animTime = (aWhichFrame == FRAME_FIRST)
                       ? 0.0f
                       : mSVGDocumentWrapper->GetCurrentTimeAsFloat();

  Maybe<SVGImageContext> newSVGContext;
  bool contextPaint =
      MaybeRestrictSVGContext(newSVGContext, aSVGContext, aFlags);

  SVGDrawingParameters params(aContext, aSize, aSize, aRegion, aSamplingFilter,
                              newSVGContext ? newSVGContext : aSVGContext,
                              animTime, aFlags, aOpacity);

  // If we have an prerasterized version of this image that matches the
  // drawing parameters, use that.
  RefPtr<SourceSurface> sourceSurface;
  Tie(sourceSurface, params.size) =
      LookupCachedSurface(aSize, params.svgContext, aFlags);
  if (sourceSurface) {
    RefPtr<gfxDrawable> drawable =
        new gfxSurfaceDrawable(sourceSurface, params.size);
    Show(drawable, params);
    return ImgDrawResult::SUCCESS;
  }

  // else, we need to paint the image:

  if (mIsDrawing) {
    NS_WARNING("Refusing to make re-entrant call to VectorImage::Draw");
    return ImgDrawResult::TEMPORARY_ERROR;
  }

  AutoRestoreSVGState autoRestore(params, mSVGDocumentWrapper, mIsDrawing,
                                  contextPaint);

  bool didCache;  // Was the surface put into the cache?
  RefPtr<gfxDrawable> svgDrawable = CreateSVGDrawable(params);
  sourceSurface = CreateSurface(params, svgDrawable, didCache);
  if (!sourceSurface) {
    MOZ_ASSERT(!didCache);
    Show(svgDrawable, params);
    return ImgDrawResult::SUCCESS;
  }

  RefPtr<gfxDrawable> drawable =
      new gfxSurfaceDrawable(sourceSurface, params.size);
  Show(drawable, params);
  SendFrameComplete(didCache, params.flags);
  return ImgDrawResult::SUCCESS;
}

already_AddRefed<gfxDrawable> VectorImage::CreateSVGDrawable(
    const SVGDrawingParameters& aParams) {
  RefPtr<gfxDrawingCallback> cb = new SVGDrawingCallback(
      mSVGDocumentWrapper, aParams.viewportSize, aParams.size, aParams.flags);

  RefPtr<gfxDrawable> svgDrawable = new gfxCallbackDrawable(cb, aParams.size);
  return svgDrawable.forget();
}

bool VectorImage::UseSurfaceCacheForSize(const IntSize& aSize) const {
  int32_t maxSizeKB = gfxPrefs::ImageCacheMaxRasterizedSVGThresholdKB();
  if (maxSizeKB <= 0) {
    return true;
  }

  if (!SurfaceCache::IsLegalSize(aSize)) {
    return false;
  }

  // With factor of 2 mode, we should be willing to use a surface which is up
  // to twice the width, and twice the height, of the maximum sized surface
  // before switching to drawing to the target directly. That means the size in
  // KB works out to be:
  //   width * height * 4 [bytes/pixel] * / 1024 [bytes/KB] <= 2 * 2 * maxSizeKB
  return aSize.width * aSize.height / 1024 <= maxSizeKB;
}

Tuple<RefPtr<SourceSurface>, IntSize> VectorImage::LookupCachedSurface(
    const IntSize& aSize, const Maybe<SVGImageContext>& aSVGContext,
    uint32_t aFlags) {
  // If we're not allowed to use a cached surface, don't attempt a lookup.
  if (aFlags & FLAG_BYPASS_SURFACE_CACHE) {
    return MakeTuple(RefPtr<SourceSurface>(), aSize);
  }

  // We don't do any caching if we have animation, so don't bother with a lookup
  // in this case either.
  if (mHaveAnimations) {
    return MakeTuple(RefPtr<SourceSurface>(), aSize);
  }

  LookupResult result(MatchType::NOT_FOUND);
  SurfaceKey surfaceKey = VectorSurfaceKey(aSize, aSVGContext);
  if ((aFlags & FLAG_SYNC_DECODE) || !(aFlags & FLAG_HIGH_QUALITY_SCALING)) {
    result = SurfaceCache::Lookup(ImageKey(this), surfaceKey,
                                  /* aMarkUsed = */ true);
  } else {
    result = SurfaceCache::LookupBestMatch(ImageKey(this), surfaceKey,
                                           /* aMarkUsed = */ true);
  }

  IntSize rasterSize =
      result.SuggestedSize().IsEmpty() ? aSize : result.SuggestedSize();
  MOZ_ASSERT(result.Type() != MatchType::SUBSTITUTE_BECAUSE_PENDING);
  if (!result || result.Type() == MatchType::SUBSTITUTE_BECAUSE_NOT_FOUND) {
    // No matching surface, or the OS freed the volatile buffer.
    return MakeTuple(RefPtr<SourceSurface>(), rasterSize);
  }

  RefPtr<SourceSurface> sourceSurface = result.Surface()->GetSourceSurface();
  if (!sourceSurface) {
    // Something went wrong. (Probably a GPU driver crash or device reset.)
    // Attempt to recover.
    RecoverFromLossOfSurfaces();
    return MakeTuple(RefPtr<SourceSurface>(), rasterSize);
  }

  return MakeTuple(std::move(sourceSurface), rasterSize);
}

already_AddRefed<SourceSurface> VectorImage::CreateSurface(
    const SVGDrawingParameters& aParams, gfxDrawable* aSVGDrawable,
    bool& aWillCache) {
  MOZ_ASSERT(mIsDrawing);

  mSVGDocumentWrapper->UpdateViewportBounds(aParams.viewportSize);
  mSVGDocumentWrapper->FlushImageTransformInvalidation();

  // Determine whether or not we should put the surface to be created into
  // the cache. If we fail, we need to reset this to false to let the caller
  // know nothing was put in the cache.
  aWillCache = !(aParams.flags & FLAG_BYPASS_SURFACE_CACHE) &&
               // Refuse to cache animated images:
               // XXX(seth): We may remove this restriction in bug 922893.
               !mHaveAnimations &&
               // The image is too big to fit in the cache:
               SurfaceCache::CanHold(aParams.size);

  // If we weren't given a context, then we know we just want the rasterized
  // surface. We will create the frame below but only insert it into the cache
  // if we actually need to.
  if (!aWillCache && aParams.context) {
    return nullptr;
  }

  // We're about to rerasterize, which may mean that some of the previous
  // surfaces we've rasterized aren't useful anymore. We can allow them to
  // expire from the cache by unlocking them here, and then sending out an
  // invalidation. If this image is locked, any surfaces that are still useful
  // will become locked again when Draw touches them, and the remainder will
  // eventually expire.
  if (aWillCache) {
    SurfaceCache::UnlockEntries(ImageKey(this));
  }

  // If there is no context, the default backend is fine.
  BackendType backend =
      aParams.context ? aParams.context->GetDrawTarget()->GetBackendType()
                      : gfxPlatform::GetPlatform()->GetDefaultContentBackend();

  // Try to create an imgFrame, initializing the surface it contains by drawing
  // our gfxDrawable into it. (We use FILTER_NEAREST since we never scale here.)
  auto frame = MakeNotNull<RefPtr<imgFrame>>();
  nsresult rv = frame->InitWithDrawable(
      aSVGDrawable, aParams.size, SurfaceFormat::B8G8R8A8,
      SamplingFilter::POINT, aParams.flags, backend);

  // If we couldn't create the frame, it was probably because it would end
  // up way too big. Generally it also wouldn't fit in the cache, but the prefs
  // could be set such that the cache isn't the limiting factor.
  if (NS_FAILED(rv)) {
    aWillCache = false;
    return nullptr;
  }

  // Take a strong reference to the frame's surface and make sure it hasn't
  // already been purged by the operating system.
  RefPtr<SourceSurface> surface = frame->GetSourceSurface();
  if (!surface) {
    aWillCache = false;
    return nullptr;
  }

  // We created the frame, but only because we had no context to draw to
  // directly. All the caller wants is the surface in this case.
  if (!aWillCache) {
    return surface.forget();
  }

  // Attempt to cache the frame.
  SurfaceKey surfaceKey = VectorSurfaceKey(aParams.size, aParams.svgContext);
  NotNull<RefPtr<ISurfaceProvider>> provider =
      MakeNotNull<SimpleSurfaceProvider*>(ImageKey(this), surfaceKey, frame);

  if (SurfaceCache::Insert(provider) == InsertOutcome::SUCCESS &&
      aParams.size != aParams.drawSize) {
    // We created a new surface that wasn't the size we requested, which means
    // we entered factor-of-2 mode. We should purge any surfaces we no longer
    // need rather than waiting for the cache to expire them.
    SurfaceCache::PruneImage(ImageKey(this));
  }

  return surface.forget();
}

void VectorImage::SendFrameComplete(bool aDidCache, uint32_t aFlags) {
  // If the cache was not updated, we have nothing to do.
  if (!aDidCache) {
    return;
  }

  // Send out an invalidation so that surfaces that are still in use get
  // re-locked. See the discussion of the UnlockSurfaces call above.
  if (!(aFlags & FLAG_ASYNC_NOTIFY)) {
    mProgressTracker->SyncNotifyProgress(FLAG_FRAME_COMPLETE,
                                         GetMaxSizedIntRect());
  } else {
    NotNull<RefPtr<VectorImage>> image = WrapNotNull(this);
    NS_DispatchToMainThread(NS_NewRunnableFunction(
        "ProgressTracker::SyncNotifyProgress", [=]() -> void {
          RefPtr<ProgressTracker> tracker = image->GetProgressTracker();
          if (tracker) {
            tracker->SyncNotifyProgress(FLAG_FRAME_COMPLETE,
                                        GetMaxSizedIntRect());
          }
        }));
  }
}

void VectorImage::Show(gfxDrawable* aDrawable,
                       const SVGDrawingParameters& aParams) {
  // The surface size may differ from the size at which we wish to draw. As
  // such, we may need to adjust the context/region to take this into account.
  gfxContextMatrixAutoSaveRestore saveMatrix(aParams.context);
  ImageRegion region(aParams.region);
  if (aParams.drawSize != aParams.size) {
    gfx::Size scale(double(aParams.drawSize.width) / aParams.size.width,
                    double(aParams.drawSize.height) / aParams.size.height);
    aParams.context->Multiply(gfxMatrix::Scaling(scale.width, scale.height));
    region.Scale(1.0 / scale.width, 1.0 / scale.height);
  }

  MOZ_ASSERT(aDrawable, "Should have a gfxDrawable by now");
  gfxUtils::DrawPixelSnapped(aParams.context, aDrawable,
                             SizeDouble(aParams.size), region,
                             SurfaceFormat::B8G8R8A8, aParams.samplingFilter,
                             aParams.flags, aParams.opacity, false);

#ifdef DEBUG
  NotifyDrawingObservers();
#endif

  MOZ_ASSERT(mRenderingObserver, "Should have a rendering observer by now");
  mRenderingObserver->ResumeHonoringInvalidations();
}

void VectorImage::RecoverFromLossOfSurfaces() {
  NS_WARNING("An imgFrame became invalid. Attempting to recover...");

  // Discard all existing frames, since they're probably all now invalid.
  SurfaceCache::RemoveImage(ImageKey(this));
}

NS_IMETHODIMP
VectorImage::StartDecoding(uint32_t aFlags) {
  // Nothing to do for SVG images
  return NS_OK;
}

bool VectorImage::StartDecodingWithResult(uint32_t aFlags) {
  // SVG images are ready to draw when they are loaded
  return mIsFullyLoaded;
}

NS_IMETHODIMP
VectorImage::RequestDecodeForSize(const nsIntSize& aSize, uint32_t aFlags) {
  // Nothing to do for SVG images, though in theory we could rasterize to the
  // provided size ahead of time if we supported off-main-thread SVG
  // rasterization...
  return NS_OK;
}

//******************************************************************************

NS_IMETHODIMP
VectorImage::LockImage() {
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return NS_ERROR_FAILURE;
  }

  mLockCount++;

  if (mLockCount == 1) {
    // Lock this image's surfaces in the SurfaceCache.
    SurfaceCache::LockImage(ImageKey(this));
  }

  return NS_OK;
}

//******************************************************************************

NS_IMETHODIMP
VectorImage::UnlockImage() {
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return NS_ERROR_FAILURE;
  }

  if (mLockCount == 0) {
    MOZ_ASSERT_UNREACHABLE("Calling UnlockImage with a zero lock count");
    return NS_ERROR_ABORT;
  }

  mLockCount--;

  if (mLockCount == 0) {
    // Unlock this image's surfaces in the SurfaceCache.
    SurfaceCache::UnlockImage(ImageKey(this));
  }

  return NS_OK;
}

//******************************************************************************

NS_IMETHODIMP
VectorImage::RequestDiscard() {
  MOZ_ASSERT(NS_IsMainThread());

  if (mDiscardable && mLockCount == 0) {
    SurfaceCache::RemoveImage(ImageKey(this));
    mProgressTracker->OnDiscard();
  }

  return NS_OK;
}

void VectorImage::OnSurfaceDiscarded(const SurfaceKey& aSurfaceKey) {
  MOZ_ASSERT(mProgressTracker);

  NS_DispatchToMainThread(NewRunnableMethod("ProgressTracker::OnDiscard",
                                            mProgressTracker,
                                            &ProgressTracker::OnDiscard));
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::ResetAnimation() {
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  if (!mIsFullyLoaded || !mHaveAnimations) {
    return NS_OK;  // There are no animations to be reset.
  }

  mSVGDocumentWrapper->ResetAnimation();

  return NS_OK;
}

NS_IMETHODIMP_(float)
VectorImage::GetFrameIndex(uint32_t aWhichFrame) {
  MOZ_ASSERT(aWhichFrame <= FRAME_MAX_VALUE, "Invalid argument");
  return aWhichFrame == FRAME_FIRST
             ? 0.0f
             : mSVGDocumentWrapper->GetCurrentTimeAsFloat();
}

//------------------------------------------------------------------------------
// nsIRequestObserver methods

//******************************************************************************
NS_IMETHODIMP
VectorImage::OnStartRequest(nsIRequest* aRequest, nsISupports* aCtxt) {
  MOZ_ASSERT(!mSVGDocumentWrapper,
             "Repeated call to OnStartRequest -- can this happen?");

  mSVGDocumentWrapper = new SVGDocumentWrapper();
  nsresult rv = mSVGDocumentWrapper->OnStartRequest(aRequest, aCtxt);
  if (NS_FAILED(rv)) {
    mSVGDocumentWrapper = nullptr;
    mError = true;
    return rv;
  }

  // Create a listener to wait until the SVG document is fully loaded, which
  // will signal that this image is ready to render. Certain error conditions
  // will prevent us from ever getting this notification, so we also create a
  // listener that waits for parsing to complete and cancels the
  // SVGLoadEventListener if needed. The listeners are automatically attached
  // to the document by their constructors.
  SVGDocument* document = mSVGDocumentWrapper->GetDocument();
  mLoadEventListener = new SVGLoadEventListener(document, this);
  mParseCompleteListener = new SVGParseCompleteListener(document, this);

  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
VectorImage::OnStopRequest(nsIRequest* aRequest, nsISupports* aCtxt,
                           nsresult aStatus) {
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  return mSVGDocumentWrapper->OnStopRequest(aRequest, aCtxt, aStatus);
}

void VectorImage::OnSVGDocumentParsed() {
  MOZ_ASSERT(mParseCompleteListener, "Should have the parse complete listener");
  MOZ_ASSERT(mLoadEventListener, "Should have the load event listener");

  if (!mSVGDocumentWrapper->GetRootSVGElem()) {
    // This is an invalid SVG document. It may have failed to parse, or it may
    // be missing the <svg> root element, or the <svg> root element may not
    // declare the correct namespace. In any of these cases, we'll never be
    // notified that the SVG finished loading, so we need to treat this as an
    // error.
    OnSVGDocumentError();
  }
}

void VectorImage::CancelAllListeners() {
  if (mParseCompleteListener) {
    mParseCompleteListener->Cancel();
    mParseCompleteListener = nullptr;
  }
  if (mLoadEventListener) {
    mLoadEventListener->Cancel();
    mLoadEventListener = nullptr;
  }
}

void VectorImage::OnSVGDocumentLoaded() {
  MOZ_ASSERT(mSVGDocumentWrapper->GetRootSVGElem(),
             "Should have parsed successfully");
  MOZ_ASSERT(!mIsFullyLoaded && !mHaveAnimations,
             "These flags shouldn't get set until OnSVGDocumentLoaded. "
             "Duplicate calls to OnSVGDocumentLoaded?");

  CancelAllListeners();

  // XXX Flushing is wasteful if embedding frame hasn't had initial reflow.
  mSVGDocumentWrapper->FlushLayout();

  mIsFullyLoaded = true;
  mHaveAnimations = mSVGDocumentWrapper->IsAnimated();

  // Start listening to our image for rendering updates.
  mRenderingObserver = new SVGRootRenderingObserver(mSVGDocumentWrapper, this);

  // ProgressTracker::SyncNotifyProgress may release us, so ensure we
  // stick around long enough to complete our work.
  RefPtr<VectorImage> kungFuDeathGrip(this);

  // Tell *our* observers that we're done loading.
  if (mProgressTracker) {
    Progress progress = FLAG_SIZE_AVAILABLE | FLAG_HAS_TRANSPARENCY |
                        FLAG_FRAME_COMPLETE | FLAG_DECODE_COMPLETE;

    if (mHaveAnimations) {
      progress |= FLAG_IS_ANIMATED;
    }

    // Merge in any saved progress from OnImageDataComplete.
    if (mLoadProgress) {
      progress |= *mLoadProgress;
      mLoadProgress = Nothing();
    }

    mProgressTracker->SyncNotifyProgress(progress, GetMaxSizedIntRect());
  }

  EvaluateAnimation();
}

void VectorImage::OnSVGDocumentError() {
  CancelAllListeners();

  mError = true;

  if (mProgressTracker) {
    // Notify observers about the error and unblock page load.
    Progress progress = FLAG_HAS_ERROR;

    // Merge in any saved progress from OnImageDataComplete.
    if (mLoadProgress) {
      progress |= *mLoadProgress;
      mLoadProgress = Nothing();
    }

    mProgressTracker->SyncNotifyProgress(progress);
  }
}

//------------------------------------------------------------------------------
// nsIStreamListener method

//******************************************************************************
NS_IMETHODIMP
VectorImage::OnDataAvailable(nsIRequest* aRequest, nsISupports* aCtxt,
                             nsIInputStream* aInStr, uint64_t aSourceOffset,
                             uint32_t aCount) {
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  return mSVGDocumentWrapper->OnDataAvailable(aRequest, aCtxt, aInStr,
                                              aSourceOffset, aCount);
}

// --------------------------
// Invalidation helper method

void VectorImage::InvalidateObserversOnNextRefreshDriverTick() {
  if (mHaveAnimations) {
    mHasPendingInvalidation = true;
  } else {
    SendInvalidationNotifications();
  }
}

void VectorImage::PropagateUseCounters(Document* aParentDocument) {
  Document* doc = mSVGDocumentWrapper->GetDocument();
  if (doc) {
    doc->PropagateUseCounters(aParentDocument);
  }
}

void VectorImage::ReportUseCounters() {
  if (Document* doc = mSVGDocumentWrapper->GetDocument()) {
    doc->ReportUseCounters();
  }
}

nsIntSize VectorImage::OptimalImageSizeForDest(const gfxSize& aDest,
                                               uint32_t aWhichFrame,
                                               SamplingFilter aSamplingFilter,
                                               uint32_t aFlags) {
  MOZ_ASSERT(aDest.width >= 0 || ceil(aDest.width) <= INT32_MAX ||
                 aDest.height >= 0 || ceil(aDest.height) <= INT32_MAX,
             "Unexpected destination size");

  // We can rescale SVGs freely, so just return the provided destination size.
  return nsIntSize::Ceil(aDest.width, aDest.height);
}

already_AddRefed<imgIContainer> VectorImage::Unwrap() {
  nsCOMPtr<imgIContainer> self(this);
  return self.forget();
}

}  // namespace image
}  // namespace mozilla