/* -*- 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/. */

// Keep in (case-insensitive) order:

#include "nsFrame.h"

#include "nsGkAtoms.h"

#include "nsSVGOuterSVGFrame.h"

#include "mozilla/dom/SVGSVGElement.h"

#include "mozilla/dom/SVGViewElement.h"

using namespace mozilla::dom;

/**

 * While views are not directly rendered in SVG they can be linked to

 * and thereby override attributes of an <svg> element via a fragment

 * identifier. The SVGViewFrame class passes on any attribute changes

 * the view receives to the overridden <svg> element (if there is one).

 **/

class SVGViewFrame final : public nsFrame

{

  friend nsIFrame*

  NS_NewSVGViewFrame(nsIPresShell* aPresShell, ComputedStyle* aStyle);

protected:

  explicit SVGViewFrame(ComputedStyle* aStyle)

    : nsFrame(aStyle, kClassID)

  {

    AddStateBits(NS_FRAME_IS_NONDISPLAY);

  }

public:

  NS_DECL_FRAMEARENA_HELPERS(SVGViewFrame)

#ifdef DEBUG

  virtual void Init(nsIContent*       aContent,

                    nsContainerFrame* aParent,

                    nsIFrame*         aPrevInFlow) override;

#endif

  virtual bool IsFrameOfType(uint32_t aFlags) const override

  {

    if (aFlags & eSupportsContainLayoutAndPaint) {

      return false;

    }

    return nsFrame::IsFrameOfType(aFlags & ~(nsIFrame::eSVG));

  }

#ifdef DEBUG_FRAME_DUMP

  virtual nsresult GetFrameName(nsAString& aResult) const override

  {

    return MakeFrameName(NS_LITERAL_STRING("SVGView"), aResult);

  }

#endif

  virtual nsresult AttributeChanged(int32_t  aNameSpaceID,

                                    nsAtom* aAttribute,

                                    int32_t  aModType) override;

  virtual bool ComputeCustomOverflow(nsOverflowAreas& aOverflowAreas) override {

    // We don't maintain a visual overflow rect

    return false;

  }

};

nsIFrame*

NS_NewSVGViewFrame(nsIPresShell* aPresShell, ComputedStyle* aStyle)

{

  return new (aPresShell) SVGViewFrame(aStyle);

}

NS_IMPL_FRAMEARENA_HELPERS(SVGViewFrame)

#ifdef DEBUG

void

SVGViewFrame::Init(nsIContent*       aContent,

                   nsContainerFrame* aParent,

                   nsIFrame*         aPrevInFlow)

{

  NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::view),

               "Content is not an SVG view");

  nsFrame::Init(aContent, aParent, aPrevInFlow);

}

#endif /* DEBUG */

nsresult

SVGViewFrame::AttributeChanged(int32_t  aNameSpaceID,

                               nsAtom* aAttribute,

                               int32_t  aModType)

{

  // Ignore zoomAndPan as it does not cause the <svg> element to re-render

  if (aNameSpaceID == kNameSpaceID_None &&

      (aAttribute == nsGkAtoms::preserveAspectRatio ||

       aAttribute == nsGkAtoms::viewBox)) {

    nsSVGOuterSVGFrame *outerSVGFrame = nsSVGUtils::GetOuterSVGFrame(this);

    NS_ASSERTION(outerSVGFrame->GetContent()->IsSVGElement(nsGkAtoms::svg),

                 "Expecting an <svg> element");

    SVGSVGElement* svgElement =

      static_cast<SVGSVGElement*>(outerSVGFrame->GetContent());

    nsAutoString viewID;

    mContent->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::id, viewID);

    if (svgElement->IsOverriddenBy(viewID)) {

      // We're the view that's providing overrides, so pretend that the frame

      // we're overriding was updated.

      outerSVGFrame->AttributeChanged(aNameSpaceID, aAttribute, aModType);

    }

  }

  return nsFrame::AttributeChanged(aNameSpaceID, aAttribute, aModType);

}