/* -*- 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 "HTMLLinkAccessible.h"

#include "nsCoreUtils.h"

#include "DocAccessible.h"

#include "Role.h"

#include "States.h"

#include "nsContentUtils.h"

#include "mozilla/EventStates.h"

#include "mozilla/dom/Element.h"

using namespace mozilla;

using namespace mozilla::a11y;

////////////////////////////////////////////////////////////////////////////////

// HTMLLinkAccessible

////////////////////////////////////////////////////////////////////////////////

HTMLLinkAccessible::

  HTMLLinkAccessible(nsIContent* aContent, DocAccessible* aDoc) :

  HyperTextAccessibleWrap(aContent, aDoc)

{

}

////////////////////////////////////////////////////////////////////////////////

// nsIAccessible

role

HTMLLinkAccessible::NativeRole() const

{

  return roles::LINK;

}

uint64_t

HTMLLinkAccessible::NativeState() const

{

  return HyperTextAccessibleWrap::NativeState() & ~states::READONLY;

}

uint64_t

HTMLLinkAccessible::NativeLinkState() const

{

  EventStates eventState = mContent->AsElement()->State();

  if (eventState.HasState(NS_EVENT_STATE_UNVISITED))

    return states::LINKED;

  if (eventState.HasState(NS_EVENT_STATE_VISITED))

    return states::LINKED | states::TRAVERSED;

  // This is a either named anchor (a link with also a name attribute) or

  // it doesn't have any attributes. Check if 'click' event handler is

  // registered, otherwise bail out.

  return nsCoreUtils::HasClickListener(mContent) ? states::LINKED : 0;

}

uint64_t

HTMLLinkAccessible::NativeInteractiveState() const

{

  uint64_t state = HyperTextAccessibleWrap::NativeInteractiveState();

  // This is how we indicate it is a named anchor. In other words, this anchor

  // can be selected as a location :) There is no other better state to use to

  // indicate this.

  if (mContent->AsElement()->HasAttr(kNameSpaceID_None, nsGkAtoms::name))

    state |= states::SELECTABLE;

  return state;

}

void

HTMLLinkAccessible::Value(nsString& aValue) const

{

  aValue.Truncate();

  HyperTextAccessible::Value(aValue);

  if (aValue.IsEmpty())

    nsContentUtils::GetLinkLocation(mContent->AsElement(), aValue);

}

uint8_t

HTMLLinkAccessible::ActionCount() const

{

  return IsLinked() ? 1 : HyperTextAccessible::ActionCount();

}

void

HTMLLinkAccessible::ActionNameAt(uint8_t aIndex, nsAString& aName)

{

  aName.Truncate();

  if (!IsLinked()) {

    HyperTextAccessible::ActionNameAt(aIndex, aName);

    return;

  }

  // Action 0 (default action): Jump to link

  if (aIndex == eAction_Jump)

    aName.AssignLiteral("jump");

}

bool

HTMLLinkAccessible::DoAction(uint8_t aIndex) const

{

  if (!IsLinked())

    return HyperTextAccessible::DoAction(aIndex);

  // Action 0 (default action): Jump to link

  if (aIndex != eAction_Jump)

    return false;

  DoCommand();

  return true;

}

////////////////////////////////////////////////////////////////////////////////

// HyperLinkAccessible

bool

HTMLLinkAccessible::IsLink() const

{

  // Expose HyperLinkAccessible unconditionally.

  return true;

}

already_AddRefed<nsIURI>

HTMLLinkAccessible::AnchorURIAt(uint32_t aAnchorIndex) const

{

  return aAnchorIndex == 0 ? mContent->GetHrefURI() : nullptr;

}

////////////////////////////////////////////////////////////////////////////////

// Protected members

bool

HTMLLinkAccessible::IsLinked() const

{

  EventStates state = mContent->AsElement()->State();

  return state.HasAtLeastOneOfStates(NS_EVENT_STATE_VISITED |

                                     NS_EVENT_STATE_UNVISITED);

}