gecko-dev/dom/svg/SVGAElement.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 "mozilla/dom/SVGAElement.h"

#include "mozilla/Attributes.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/EventStates.h"
#include "mozilla/dom/SVGAElementBinding.h"
#include "nsCOMPtr.h"
#include "nsContentUtils.h"
#include "nsGkAtoms.h"
#include "nsSVGString.h"
#include "nsIURI.h"

NS_IMPL_NS_NEW_NAMESPACED_SVG_ELEMENT(A)

namespace mozilla {
namespace dom {

JSObject*
SVGAElement::WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto)
{
  return SVGAElementBinding::Wrap(aCx, this, aGivenProto);
}

nsSVGElement::StringInfo SVGAElement::sStringInfo[3] =
{
  { &nsGkAtoms::href, kNameSpaceID_None, true },
  { &nsGkAtoms::href, kNameSpaceID_XLink, true },
  { &nsGkAtoms::target, kNameSpaceID_None, true }
};


//----------------------------------------------------------------------
// nsISupports methods

NS_INTERFACE_MAP_BEGIN(SVGAElement)
  NS_INTERFACE_MAP_ENTRY(nsIDOMNode)
  NS_INTERFACE_MAP_ENTRY(nsIDOMElement)
  NS_INTERFACE_MAP_ENTRY(nsIDOMSVGElement)
  NS_INTERFACE_MAP_ENTRY(Link)
NS_INTERFACE_MAP_END_INHERITING(SVGAElementBase)

NS_IMPL_ADDREF_INHERITED(SVGAElement, SVGAElementBase)
NS_IMPL_RELEASE_INHERITED(SVGAElement, SVGAElementBase)

//----------------------------------------------------------------------
// Implementation

SVGAElement::SVGAElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
  : SVGAElementBase(aNodeInfo)
  , Link(this)
{
}

SVGAElement::~SVGAElement()
{
}

already_AddRefed<SVGAnimatedString>
SVGAElement::Href()
{
  return mStringAttributes[HREF].IsExplicitlySet()
         ? mStringAttributes[HREF].ToDOMAnimatedString(this)
         : mStringAttributes[XLINK_HREF].ToDOMAnimatedString(this);
}

//----------------------------------------------------------------------
// Link methods

bool
SVGAElement::ElementHasHref() const
{
  return mStringAttributes[HREF].IsExplicitlySet() ||
         mStringAttributes[XLINK_HREF].IsExplicitlySet();
}

//----------------------------------------------------------------------
// nsINode methods

nsresult
SVGAElement::GetEventTargetParent(EventChainPreVisitor& aVisitor)
{
  nsresult rv = Element::GetEventTargetParent(aVisitor);
  NS_ENSURE_SUCCESS(rv, rv);

  return GetEventTargetParentForLinks(aVisitor);
}

nsresult
SVGAElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
{
  return PostHandleEventForLinks(aVisitor);
}

NS_IMPL_ELEMENT_CLONE_WITH_INIT(SVGAElement)


//----------------------------------------------------------------------

already_AddRefed<SVGAnimatedString>
SVGAElement::Target()
{
  return mStringAttributes[TARGET].ToDOMAnimatedString(this);
}

void
SVGAElement::GetDownload(nsAString & aDownload)
{
  GetAttr(kNameSpaceID_None, nsGkAtoms::download, aDownload);
}

void
SVGAElement::SetDownload(const nsAString & aDownload, ErrorResult& rv)
{
  rv = SetAttr(kNameSpaceID_None, nsGkAtoms::download, aDownload, true);
}

//----------------------------------------------------------------------
// nsIContent methods

nsresult
SVGAElement::BindToTree(nsIDocument *aDocument, nsIContent *aParent,
                        nsIContent *aBindingParent,
                        bool aCompileEventHandlers)
{
  Link::ResetLinkState(false, Link::ElementHasHref());

  nsresult rv = SVGAElementBase::BindToTree(aDocument, aParent,
                                            aBindingParent,
                                            aCompileEventHandlers);
  NS_ENSURE_SUCCESS(rv, rv);

  nsIDocument* doc = GetComposedDoc();
  if (doc) {
    doc->RegisterPendingLinkUpdate(this);
  }

  return NS_OK;
}

void
SVGAElement::UnbindFromTree(bool aDeep, bool aNullParent)
{
  // If this link is ever reinserted into a document, it might
  // be under a different xml:base, so forget the cached state now.
  Link::ResetLinkState(false, Link::ElementHasHref());

  SVGAElementBase::UnbindFromTree(aDeep, aNullParent);
}

already_AddRefed<nsIURI>
SVGAElement::GetHrefURI() const
{
  nsCOMPtr<nsIURI> hrefURI;
  return IsLink(getter_AddRefs(hrefURI)) ? hrefURI.forget() : nullptr;
}


NS_IMETHODIMP_(bool)
SVGAElement::IsAttributeMapped(const nsAtom* name) const
{
  static const MappedAttributeEntry* const map[] = {
    sFEFloodMap,
    sFiltersMap,
    sFontSpecificationMap,
    sGradientStopMap,
    sLightingEffectsMap,
    sMarkersMap,
    sTextContentElementsMap,
    sViewportsMap
  };

  return FindAttributeDependence(name, map) ||
    SVGAElementBase::IsAttributeMapped(name);
}

int32_t
SVGAElement::TabIndexDefault()
{
  return 0;
}

static bool
IsNodeInEditableRegion(nsINode* aNode)
{
  while (aNode) {
    if (aNode->IsEditable()) {
      return true;
    }
    aNode = aNode->GetParent();
  }
  return false;
}

bool
SVGAElement::IsSVGFocusable(bool* aIsFocusable, int32_t* aTabIndex)
{
  if (nsSVGElement::IsSVGFocusable(aIsFocusable, aTabIndex)) {
    return true;
  }

  // cannot focus links if there is no link handler
  nsIDocument* doc = GetComposedDoc();
  if (doc) {
    nsIPresShell* presShell = doc->GetShell();
    if (presShell) {
      nsPresContext* presContext = presShell->GetPresContext();
      if (presContext && !presContext->GetLinkHandler()) {
        *aIsFocusable = false;
        return false;
      }
    }
  }

  // Links that are in an editable region should never be focusable, even if
  // they are in a contenteditable="false" region.
  if (IsNodeInEditableRegion(this)) {
    if (aTabIndex) {
      *aTabIndex = -1;
    }

    *aIsFocusable = false;

    return true;
  }

  if (!HasAttr(kNameSpaceID_None, nsGkAtoms::tabindex)) {
    // check whether we're actually a link
    if (!Link::HasURI()) {
      // Not tabbable or focusable without href (bug 17605), unless
      // forced to be via presence of nonnegative tabindex attribute
      if (aTabIndex) {
        *aTabIndex = -1;
      }

      *aIsFocusable = false;

      return false;
    }
  }

  if (aTabIndex && (sTabFocusModel & eTabFocus_linksMask) == 0) {
    *aTabIndex = -1;
  }

  *aIsFocusable = true;

  return false;
}

bool
SVGAElement::IsLink(nsIURI** aURI) const
{
  // To be a clickable XLink for styling and interaction purposes, we require:
  //
  //   xlink:href    - must be set
  //   xlink:type    - must be unset or set to "" or set to "simple"
  //   xlink:show    - must be unset or set to "", "new" or "replace"
  //   xlink:actuate - must be unset or set to "" or "onRequest"
  //
  // For any other values, we're either not a *clickable* XLink, or the end
  // result is poorly specified. Either way, we return false.

  static nsIContent::AttrValuesArray sTypeVals[] =
    { &nsGkAtoms::_empty, &nsGkAtoms::simple, nullptr };

  static nsIContent::AttrValuesArray sShowVals[] =
    { &nsGkAtoms::_empty, &nsGkAtoms::_new, &nsGkAtoms::replace, nullptr };

  static nsIContent::AttrValuesArray sActuateVals[] =
    { &nsGkAtoms::_empty, &nsGkAtoms::onRequest, nullptr };

  // Optimization: check for href first for early return
  bool useBareHref = mStringAttributes[HREF].IsExplicitlySet();

  if ((useBareHref || mStringAttributes[XLINK_HREF].IsExplicitlySet()) &&
      FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::type,
                      sTypeVals, eCaseMatters) !=
                      nsIContent::ATTR_VALUE_NO_MATCH &&
      FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::show,
                      sShowVals, eCaseMatters) !=
                      nsIContent::ATTR_VALUE_NO_MATCH &&
      FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::actuate,
                      sActuateVals, eCaseMatters) !=
                      nsIContent::ATTR_VALUE_NO_MATCH) {
    nsCOMPtr<nsIURI> baseURI = GetBaseURI();
    // Get absolute URI
    nsAutoString str;
    const uint8_t idx = useBareHref ? HREF : XLINK_HREF;
    mStringAttributes[idx].GetAnimValue(str, this);
    nsContentUtils::NewURIWithDocumentCharset(aURI, str, OwnerDoc(), baseURI);
    // must promise out param is non-null if we return true
    return !!*aURI;
  }

  *aURI = nullptr;
  return false;
}

void
SVGAElement::GetLinkTarget(nsAString& aTarget)
{
  mStringAttributes[TARGET].GetAnimValue(aTarget, this);
  if (aTarget.IsEmpty()) {

    static nsIContent::AttrValuesArray sShowVals[] =
      { &nsGkAtoms::_new, &nsGkAtoms::replace, nullptr };

    switch (FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::show,
                            sShowVals, eCaseMatters)) {
    case 0:
      aTarget.AssignLiteral("_blank");
      return;
    case 1:
      return;
    }
    nsIDocument* ownerDoc = OwnerDoc();
    if (ownerDoc) {
      ownerDoc->GetBaseTarget(aTarget);
    }
  }
}

EventStates
SVGAElement::IntrinsicState() const
{
  return Link::LinkState() | SVGAElementBase::IntrinsicState();
}

nsresult
SVGAElement::SetAttr(int32_t aNameSpaceID, nsAtom* aName,
                     nsAtom* aPrefix, const nsAString& aValue,
                     nsIPrincipal* aSubjectPrincipal,
                     bool aNotify)
{
  nsresult rv = SVGAElementBase::SetAttr(aNameSpaceID, aName, aPrefix,
                                         aValue, aSubjectPrincipal, aNotify);

  // The ordering of the parent class's SetAttr call and Link::ResetLinkState
  // is important here!  The attribute is not set until SetAttr returns, and
  // we will need the updated attribute value because notifying the document
  // that content states have changed will call IntrinsicState, which will try
  // to get updated information about the visitedness from Link.
  if (aName == nsGkAtoms::href &&
      (aNameSpaceID == kNameSpaceID_XLink ||
       aNameSpaceID == kNameSpaceID_None)) {
    Link::ResetLinkState(!!aNotify, true);
  }

  return rv;
}

nsresult
SVGAElement::UnsetAttr(int32_t aNameSpaceID, nsAtom* aAttr,
                       bool aNotify)
{
  nsresult rv = nsSVGElement::UnsetAttr(aNameSpaceID, aAttr, aNotify);

  // The ordering of the parent class's UnsetAttr call and Link::ResetLinkState
  // is important here!  The attribute is not unset until UnsetAttr returns, and
  // we will need the updated attribute value because notifying the document
  // that content states have changed will call IntrinsicState, which will try
  // to get updated information about the visitedness from Link.
  if (aAttr == nsGkAtoms::href &&
      (aNameSpaceID == kNameSpaceID_XLink ||
       aNameSpaceID == kNameSpaceID_None)) {
    Link::ResetLinkState(!!aNotify, Link::ElementHasHref());
  }

  return rv;
}

//----------------------------------------------------------------------
// nsSVGElement methods

nsSVGElement::StringAttributesInfo
SVGAElement::GetStringInfo()
{
  return StringAttributesInfo(mStringAttributes, sStringInfo,
                              ArrayLength(sStringInfo));
}

} // namespace dom
} // namespace mozilla