gecko-dev/dom/base/AnonymousContent.cpp

/* -*- 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/. */

#include "AnonymousContent.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/AnonymousContentBinding.h"
#include "nsComputedDOMStyle.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIDocument.h"
#include "nsIFrame.h"
#include "nsStyledElement.h"
#include "HTMLCanvasElement.h"

namespace mozilla {
namespace dom {

// Ref counting and cycle collection
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(AnonymousContent, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(AnonymousContent, Release)
NS_IMPL_CYCLE_COLLECTION(AnonymousContent, mContentNode)

AnonymousContent::AnonymousContent(already_AddRefed<Element> aContentNode)
  : mContentNode(aContentNode)
{
  MOZ_ASSERT(mContentNode);
}

AnonymousContent::~AnonymousContent() = default;

void
AnonymousContent::SetTextContentForElement(const nsAString& aElementId,
                                           const nsAString& aText,
                                           ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  element->SetTextContent(aText, aRv);
}

void
AnonymousContent::GetTextContentForElement(const nsAString& aElementId,
                                           DOMString& aText,
                                           ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  element->GetTextContent(aText, aRv);
}

void
AnonymousContent::SetAttributeForElement(const nsAString& aElementId,
                                         const nsAString& aName,
                                         const nsAString& aValue,
                                         nsIPrincipal* aSubjectPrincipal,
                                         ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  element->SetAttribute(aName, aValue, aSubjectPrincipal, aRv);
}

void
AnonymousContent::GetAttributeForElement(const nsAString& aElementId,
                                         const nsAString& aName,
                                         DOMString& aValue,
                                         ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  element->GetAttribute(aName, aValue);
}

void
AnonymousContent::RemoveAttributeForElement(const nsAString& aElementId,
                                            const nsAString& aName,
                                            ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  element->RemoveAttribute(aName, aRv);
}

already_AddRefed<nsISupports>
AnonymousContent::GetCanvasContext(const nsAString& aElementId,
                                   const nsAString& aContextId,
                                   ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);

  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return nullptr;
  }

  if (!element->IsHTMLElement(nsGkAtoms::canvas)) {
    return nullptr;
  }

  nsCOMPtr<nsISupports> context;

  HTMLCanvasElement* canvas = static_cast<HTMLCanvasElement*>(element);
  canvas->GetContext(aContextId, getter_AddRefs(context));

  return context.forget();
}

already_AddRefed<Animation>
AnonymousContent::SetAnimationForElement(JSContext* aContext,
                                         const nsAString& aElementId,
                                         JS::Handle<JSObject*> aKeyframes,
                                         const UnrestrictedDoubleOrKeyframeAnimationOptions& aOptions,
                                         ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);

  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return nullptr;
  }

  return element->Animate(aContext, aKeyframes, aOptions, aRv);
}

void
AnonymousContent::SetCutoutRectsForElement(const nsAString& aElementId,
                                           const Sequence<OwningNonNull<DOMRect>>& aRects,
                                           ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);

  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  nsRegion cutOutRegion;
  for (const auto& r : aRects) {
    CSSRect rect(r->X(), r->Y(), r->Width(), r->Height());
    cutOutRegion.OrWith(CSSRect::ToAppUnits(rect));
  }

  element->SetProperty(nsGkAtoms::cutoutregion, new nsRegion(cutOutRegion),
                       nsINode::DeleteProperty<nsRegion>);

  nsIFrame* frame = element->GetPrimaryFrame();
  if (frame) {
    frame->SchedulePaint();
  }
}

Element*
AnonymousContent::GetElementById(const nsAString& aElementId)
{
  // This can be made faster in the future if needed.
  RefPtr<nsAtom> elementId = NS_Atomize(aElementId);
  for (nsIContent* node = mContentNode; node;
       node = node->GetNextNode(mContentNode)) {
    if (!node->IsElement()) {
      continue;
    }
    nsAtom* id = node->AsElement()->GetID();
    if (id && id == elementId) {
      return node->AsElement();
    }
  }
  return nullptr;
}

bool
AnonymousContent::WrapObject(JSContext* aCx,
                             JS::Handle<JSObject*> aGivenProto,
                             JS::MutableHandle<JSObject*> aReflector)
{
  return AnonymousContent_Binding::Wrap(aCx, this, aGivenProto, aReflector);
}

void
AnonymousContent::GetComputedStylePropertyValue(const nsAString& aElementId,
                                                const nsAString& aPropertyName,
                                                DOMString& aResult,
                                                ErrorResult& aRv)
{
  Element* element = GetElementById(aElementId);
  if (!element) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  nsIPresShell* shell = element->OwnerDoc()->GetShell();
  if (!shell) {
    aRv.Throw(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  RefPtr<nsComputedDOMStyle> cs =
    new nsComputedDOMStyle(element,
                           NS_LITERAL_STRING(""),
                           element->OwnerDoc(),
                           nsComputedDOMStyle::eAll);
  aRv = cs->GetPropertyValue(aPropertyName, aResult);
}

} // namespace dom
} // namespace mozilla