path: root/accessible/base/ARIAStateMap.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=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 "ARIAMap.h"
#include "nsAccUtils.h"
#include "States.h"

#include "mozilla/dom/Element.h"

using namespace mozilla;
using namespace mozilla::a11y;
using namespace mozilla::a11y::aria;

/**
 * Used to store state map rule data for ARIA attribute of enum type.
 */
struct EnumTypeData {
  // ARIA attribute name.
  nsStaticAtom* const mAttrName;

  // States if the attribute value is matched to the enum value. Used as
  // Element::AttrValuesArray, last item must be nullptr.
  nsStaticAtom* const mValues[4];

  // States applied if corresponding enum values are matched.
  const uint64_t mStates[3];

  // States to clear in case of match.
  const uint64_t mClearState;
};

enum ETokenType {
  eBoolType = 0,
  eMixedType = 1,       // can take 'mixed' value
  eDefinedIfAbsent = 2  // permanent and false state are applied if absent
};

/**
 * Used to store state map rule data for ARIA attribute of token type (including
 * mixed value).
 */
struct TokenTypeData {
  TokenTypeData(nsAtom* aAttrName, uint32_t aType, uint64_t aPermanentState,
                uint64_t aTrueState, uint64_t aFalseState = 0)
      : mAttrName(aAttrName),
        mType(aType),
        mPermanentState(aPermanentState),
        mTrueState(aTrueState),
        mFalseState(aFalseState) {}

  // ARIA attribute name.
  nsAtom* const mAttrName;

  // Type.
  const uint32_t mType;

  // State applied if the attribute is defined or mType doesn't have
  // eDefinedIfAbsent flag set.
  const uint64_t mPermanentState;

  // States applied if the attribute value is true/false.
  const uint64_t mTrueState;
  const uint64_t mFalseState;
};

/**
 * Map enum type attribute value to accessible state.
 */
static void MapEnumType(dom::Element* aElement, uint64_t* aState,
                        const EnumTypeData& aData);

/**
 * Map token type attribute value to states.
 */
static void MapTokenType(dom::Element* aContent, uint64_t* aState,
                         const TokenTypeData& aData);

bool aria::MapToState(EStateRule aRule, dom::Element* aElement,
                      uint64_t* aState) {
  switch (aRule) {
    case eARIAAutoComplete: {
      static const EnumTypeData data = {
          nsGkAtoms::aria_autocomplete,
          {nsGkAtoms::inlinevalue, nsGkAtoms::list_, nsGkAtoms::both, nullptr},
          {states::SUPPORTS_AUTOCOMPLETION,
           states::HASPOPUP | states::SUPPORTS_AUTOCOMPLETION,
           states::HASPOPUP | states::SUPPORTS_AUTOCOMPLETION},
          0};

      MapEnumType(aElement, aState, data);
      return true;
    }

    case eARIABusy: {
      static const EnumTypeData data = {
          nsGkAtoms::aria_busy,
          {nsGkAtoms::_true, nsGkAtoms::error, nullptr},
          {states::BUSY, states::INVALID},
          0};

      MapEnumType(aElement, aState, data);
      return true;
    }

    case eARIACheckableBool: {
      static const TokenTypeData data(nsGkAtoms::aria_checked,
                                      eBoolType | eDefinedIfAbsent,
                                      states::CHECKABLE, states::CHECKED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIACheckableMixed: {
      static const TokenTypeData data(nsGkAtoms::aria_checked,
                                      eMixedType | eDefinedIfAbsent,
                                      states::CHECKABLE, states::CHECKED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIACheckedMixed: {
      static const TokenTypeData data(nsGkAtoms::aria_checked, eMixedType,
                                      states::CHECKABLE, states::CHECKED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIACurrent: {
      static const TokenTypeData data(nsGkAtoms::aria_current, eBoolType, 0,
                                      states::CURRENT);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIADisabled: {
      static const TokenTypeData data(nsGkAtoms::aria_disabled, eBoolType, 0,
                                      states::UNAVAILABLE);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAExpanded: {
      static const TokenTypeData data(nsGkAtoms::aria_expanded, eBoolType, 0,
                                      states::EXPANDED, states::COLLAPSED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAHasPopup: {
      static const TokenTypeData data(nsGkAtoms::aria_haspopup, eBoolType, 0,
                                      states::HASPOPUP);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAInvalid: {
      static const TokenTypeData data(nsGkAtoms::aria_invalid, eBoolType, 0,
                                      states::INVALID);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAModal: {
      static const TokenTypeData data(nsGkAtoms::aria_modal, eBoolType, 0,
                                      states::MODAL);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAMultiline: {
      static const TokenTypeData data(nsGkAtoms::aria_multiline,
                                      eBoolType | eDefinedIfAbsent, 0,
                                      states::MULTI_LINE, states::SINGLE_LINE);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAMultiSelectable: {
      static const TokenTypeData data(
          nsGkAtoms::aria_multiselectable, eBoolType, 0,
          states::MULTISELECTABLE | states::EXTSELECTABLE);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAOrientation: {
      static const EnumTypeData data = {
          nsGkAtoms::aria_orientation,
          {nsGkAtoms::horizontal, nsGkAtoms::vertical, nullptr},
          {states::HORIZONTAL, states::VERTICAL},
          states::HORIZONTAL | states::VERTICAL};

      MapEnumType(aElement, aState, data);
      return true;
    }

    case eARIAPressed: {
      static const TokenTypeData data(nsGkAtoms::aria_pressed, eMixedType, 0,
                                      states::PRESSED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAReadonly: {
      static const TokenTypeData data(nsGkAtoms::aria_readonly, eBoolType, 0,
                                      states::READONLY);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIAReadonlyOrEditable: {
      static const TokenTypeData data(nsGkAtoms::aria_readonly,
                                      eBoolType | eDefinedIfAbsent, 0,
                                      states::READONLY, states::EDITABLE);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIARequired: {
      static const TokenTypeData data(nsGkAtoms::aria_required, eBoolType, 0,
                                      states::REQUIRED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIASelectable: {
      static const TokenTypeData data(nsGkAtoms::aria_selected,
                                      eBoolType | eDefinedIfAbsent,
                                      states::SELECTABLE, states::SELECTED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eARIASelectableIfDefined: {
      static const TokenTypeData data(nsGkAtoms::aria_selected, eBoolType,
                                      states::SELECTABLE, states::SELECTED);

      MapTokenType(aElement, aState, data);
      return true;
    }

    case eReadonlyUntilEditable: {
      if (!(*aState & states::EDITABLE)) *aState |= states::READONLY;

      return true;
    }

    case eIndeterminateIfNoValue: {
      if (!nsAccUtils::HasARIAAttr(aElement, nsGkAtoms::aria_valuenow) &&
          !nsAccUtils::HasARIAAttr(aElement, nsGkAtoms::aria_valuetext)) {
        *aState |= states::MIXED;
      }

      return true;
    }

    case eFocusableUntilDisabled: {
      if (!nsAccUtils::HasDefinedARIAToken(aElement,
                                           nsGkAtoms::aria_disabled) ||
          nsAccUtils::ARIAAttrValueIs(aElement, nsGkAtoms::aria_disabled,
                                      nsGkAtoms::_false, eCaseMatters)) {
        *aState |= states::FOCUSABLE;
      }

      return true;
    }

    default:
      return false;
  }
}

static void MapEnumType(dom::Element* aElement, uint64_t* aState,
                        const EnumTypeData& aData) {
  switch (nsAccUtils::FindARIAAttrValueIn(aElement, aData.mAttrName,
                                          aData.mValues, eCaseMatters)) {
    case 0:
      *aState = (*aState & ~aData.mClearState) | aData.mStates[0];
      return;
    case 1:
      *aState = (*aState & ~aData.mClearState) | aData.mStates[1];
      return;
    case 2:
      *aState = (*aState & ~aData.mClearState) | aData.mStates[2];
      return;
  }
}

static void MapTokenType(dom::Element* aElement, uint64_t* aState,
                         const TokenTypeData& aData) {
  if (nsAccUtils::HasDefinedARIAToken(aElement, aData.mAttrName)) {
    if (nsAccUtils::ARIAAttrValueIs(aElement, aData.mAttrName, nsGkAtoms::mixed,
                                    eCaseMatters)) {
      if (aData.mType & eMixedType) {
        *aState |= aData.mPermanentState | states::MIXED;
      } else {  // unsupported use of 'mixed' is an authoring error
        *aState |= aData.mPermanentState | aData.mFalseState;
      }
      return;
    }

    if (nsAccUtils::ARIAAttrValueIs(aElement, aData.mAttrName,
                                    nsGkAtoms::_false, eCaseMatters)) {
      *aState |= aData.mPermanentState | aData.mFalseState;
      return;
    }

    *aState |= aData.mPermanentState | aData.mTrueState;
    return;
  }

  if (aData.mType & eDefinedIfAbsent) {
    *aState |= aData.mPermanentState | aData.mFalseState;
  }
}