/* -*- 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/HTMLAnchorElement.h"

#include "mozilla/dom/HTMLAnchorElementBinding.h"

#include "mozilla/EventDispatcher.h"

#include "mozilla/EventStates.h"

#include "mozilla/MemoryReporting.h"

#include "nsCOMPtr.h"

#include "nsContentUtils.h"

#include "nsGkAtoms.h"

#include "nsHTMLDNSPrefetch.h"

#include "nsAttrValueOrString.h"

#include "nsIDocument.h"

#include "nsIPresShell.h"

#include "nsPresContext.h"

#include "nsIURI.h"

#include "nsWindowSizes.h"

NS_IMPL_NS_NEW_HTML_ELEMENT(Anchor)

namespace mozilla {

namespace dom {

#define ANCHOR_ELEMENT_FLAG_BIT(n_) NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))

// Anchor element specific bits

enum {

  // Indicates that a DNS Prefetch has been requested from this Anchor elem

  HTML_ANCHOR_DNS_PREFETCH_REQUESTED =    ANCHOR_ELEMENT_FLAG_BIT(0),

  // Indicates that a DNS Prefetch was added to the deferral queue

  HTML_ANCHOR_DNS_PREFETCH_DEFERRED =     ANCHOR_ELEMENT_FLAG_BIT(1)

};

ASSERT_NODE_FLAGS_SPACE(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + 2);

#undef ANCHOR_ELEMENT_FLAG_BIT

// static

const DOMTokenListSupportedToken HTMLAnchorElement::sSupportedRelValues[] = {

  "noreferrer",

  "noopener",

  nullptr

};

HTMLAnchorElement::~HTMLAnchorElement()

{

}

bool

HTMLAnchorElement::IsInteractiveHTMLContent(bool aIgnoreTabindex) const

{

  return HasAttr(kNameSpaceID_None, nsGkAtoms::href) ||

         nsGenericHTMLElement::IsInteractiveHTMLContent(aIgnoreTabindex);

}

NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(HTMLAnchorElement,

                                             nsGenericHTMLElement,

                                             Link)

NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLAnchorElement,

                                   nsGenericHTMLElement,

                                   mRelList)

NS_IMPL_ELEMENT_CLONE(HTMLAnchorElement)

JSObject*

HTMLAnchorElement::WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto)

{

  return HTMLAnchorElement_Binding::Wrap(aCx, this, aGivenProto);

}

int32_t

HTMLAnchorElement::TabIndexDefault()

{

  return 0;

}

bool

HTMLAnchorElement::Draggable() const

{

  // links can be dragged as long as there is an href and the

  // draggable attribute isn't false

  if (!HasAttr(kNameSpaceID_None, nsGkAtoms::href)) {

    // no href, so just use the same behavior as other elements

    return nsGenericHTMLElement::Draggable();

  }

  return !AttrValueIs(kNameSpaceID_None, nsGkAtoms::draggable,

                      nsGkAtoms::_false, eIgnoreCase);

}

void

HTMLAnchorElement::OnDNSPrefetchRequested()

{

  UnsetFlags(HTML_ANCHOR_DNS_PREFETCH_DEFERRED);

  SetFlags(HTML_ANCHOR_DNS_PREFETCH_REQUESTED);

}

void

HTMLAnchorElement::OnDNSPrefetchDeferred()

{

  UnsetFlags(HTML_ANCHOR_DNS_PREFETCH_REQUESTED);

  SetFlags(HTML_ANCHOR_DNS_PREFETCH_DEFERRED);

}

bool

HTMLAnchorElement::HasDeferredDNSPrefetchRequest()

{

  return HasFlag(HTML_ANCHOR_DNS_PREFETCH_DEFERRED);

}

nsresult

HTMLAnchorElement::BindToTree(nsIDocument* aDocument, nsIContent* aParent,

                              nsIContent* aBindingParent)

{

  Link::ResetLinkState(false, Link::ElementHasHref());

  nsresult rv = nsGenericHTMLElement::BindToTree(aDocument, aParent,

                                                 aBindingParent);

  NS_ENSURE_SUCCESS(rv, rv);

  // Prefetch links

  nsIDocument* doc = GetComposedDoc();

  if (doc) {

    doc->RegisterPendingLinkUpdate(this);

    TryDNSPrefetch();

  }

  return rv;

}

void

HTMLAnchorElement::UnbindFromTree(bool aDeep, bool aNullParent)

{

  // Cancel any DNS prefetches

  // Note: Must come before ResetLinkState.  If called after, it will recreate

  // mCachedURI based on data that is invalid - due to a call to GetHostname.

  CancelDNSPrefetch(HTML_ANCHOR_DNS_PREFETCH_DEFERRED,

                    HTML_ANCHOR_DNS_PREFETCH_REQUESTED);

  // 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());

  nsGenericHTMLElement::UnbindFromTree(aDeep, aNullParent);

}

static bool

IsNodeInEditableRegion(nsINode* aNode)

{

  while (aNode) {

    if (aNode->IsEditable()) {

      return true;

    }

    aNode = aNode->GetParent();

  }

  return false;

}

bool

HTMLAnchorElement::IsHTMLFocusable(bool aWithMouse,

                                   bool *aIsFocusable, int32_t *aTabIndex)

{

  if (nsGenericHTMLElement::IsHTMLFocusable(aWithMouse, aIsFocusable, aTabIndex)) {

    return true;

  }

  // cannot focus links if there is no link handler

  nsIDocument* doc = GetComposedDoc();

  if (doc) {

    nsPresContext* presContext = doc->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;

}

void

HTMLAnchorElement::GetEventTargetParent(EventChainPreVisitor& aVisitor)

{

  GetEventTargetParentForAnchors(aVisitor);

}

nsresult

HTMLAnchorElement::PostHandleEvent(EventChainPostVisitor& aVisitor)

{

  return PostHandleEventForAnchors(aVisitor);

}

bool

HTMLAnchorElement::IsLink(nsIURI** aURI) const

{

  return IsHTMLLink(aURI);

}

void

HTMLAnchorElement::GetLinkTarget(nsAString& aTarget)

{

  GetAttr(kNameSpaceID_None, nsGkAtoms::target, aTarget);

  if (aTarget.IsEmpty()) {

    GetBaseTarget(aTarget);

  }

}

void

HTMLAnchorElement::GetTarget(nsAString& aValue)

{

  if (!GetAttr(kNameSpaceID_None, nsGkAtoms::target, aValue)) {

    GetBaseTarget(aValue);

  }

}

nsDOMTokenList*

HTMLAnchorElement::RelList()

{

  if (!mRelList) {

    mRelList = new nsDOMTokenList(this, nsGkAtoms::rel, sSupportedRelValues);

  }

  return mRelList;

}

void

HTMLAnchorElement::GetText(nsAString& aText, mozilla::ErrorResult& aRv)

{

  if (NS_WARN_IF(!nsContentUtils::GetNodeTextContent(this, true, aText, fallible))) {

    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);

  }

}

void

HTMLAnchorElement::SetText(const nsAString& aText, ErrorResult& aRv)

{

  aRv = nsContentUtils::SetNodeTextContent(this, aText, false);

}

void

HTMLAnchorElement::ToString(nsAString& aSource)

{

  return GetHref(aSource);

}

already_AddRefed<nsIURI>

HTMLAnchorElement::GetHrefURI() const

{

  nsCOMPtr<nsIURI> uri = Link::GetCachedURI();

  if (uri) {

    return uri.forget();

  }

  return GetHrefURIForAnchors();

}

nsresult

HTMLAnchorElement::BeforeSetAttr(int32_t aNamespaceID, nsAtom* aName,

                                 const nsAttrValueOrString* aValue,

                                 bool aNotify)

{

  if (aNamespaceID == kNameSpaceID_None) {

    if (aName == nsGkAtoms::href) {

      CancelDNSPrefetch(HTML_ANCHOR_DNS_PREFETCH_DEFERRED,

                        HTML_ANCHOR_DNS_PREFETCH_REQUESTED);

    }

  }

  return nsGenericHTMLElement::BeforeSetAttr(aNamespaceID, aName, aValue,

                                             aNotify);

}

nsresult

HTMLAnchorElement::AfterSetAttr(int32_t aNamespaceID, nsAtom* aName,

                                const nsAttrValue* aValue,

                                const nsAttrValue* aOldValue,

                                nsIPrincipal* aSubjectPrincipal,

                                bool aNotify)

{

  if (aNamespaceID == kNameSpaceID_None) {

    if (aName == nsGkAtoms::href) {

      Link::ResetLinkState(aNotify, !!aValue);

      if (aValue && IsInComposedDoc()) {

        TryDNSPrefetch();

      }

    }

  }

  return nsGenericHTMLElement::AfterSetAttr(aNamespaceID, aName,

                                            aValue, aOldValue, aSubjectPrincipal, aNotify);

}

EventStates

HTMLAnchorElement::IntrinsicState() const

{

  return Link::LinkState() | nsGenericHTMLElement::IntrinsicState();

}

void

HTMLAnchorElement::AddSizeOfExcludingThis(nsWindowSizes& aSizes,

                                          size_t* aNodeSize) const

{

  nsGenericHTMLElement::AddSizeOfExcludingThis(aSizes, aNodeSize);

  *aNodeSize += Link::SizeOfExcludingThis(aSizes.mState);

}

} // namespace dom

} // namespace mozilla