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/* -*- 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 "nsAccUtils.h"
#include "LocalAccessible-inl.h"
#include "AccAttributes.h"
#include "ARIAMap.h"
#include "nsAccessibilityService.h"
#include "nsCoreUtils.h"
#include "DocAccessible.h"
#include "HyperTextAccessible.h"
#include "nsIAccessibleTypes.h"
#include "Role.h"
#include "States.h"
#include "TextLeafAccessible.h"
#include "nsIDOMXULContainerElement.h"
#include "nsISimpleEnumerator.h"
#include "mozilla/a11y/PDocAccessibleChild.h"
#include "mozilla/a11y/RemoteAccessible.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/Element.h"
#include "mozilla/StaticPrefs_accessibility.h"
#include "nsAccessibilityService.h"
using namespace mozilla;
using namespace mozilla::a11y;
void nsAccUtils::SetAccGroupAttrs(AccAttributes* aAttributes, int32_t aLevel,
int32_t aSetSize, int32_t aPosInSet) {
nsAutoString value;
if (aLevel) {
aAttributes->SetAttribute(nsGkAtoms::level, aLevel);
}
if (aSetSize && aPosInSet) {
aAttributes->SetAttribute(nsGkAtoms::posinset, aPosInSet);
aAttributes->SetAttribute(nsGkAtoms::setsize, aSetSize);
}
}
int32_t nsAccUtils::GetDefaultLevel(const LocalAccessible* aAccessible) {
roles::Role role = aAccessible->Role();
if (role == roles::OUTLINEITEM) return 1;
if (role == roles::ROW) {
LocalAccessible* parent = aAccessible->LocalParent();
// It is a row inside flatten treegrid. Group level is always 1 until it
// is overriden by aria-level attribute.
if (parent && parent->Role() == roles::TREE_TABLE) return 1;
}
return 0;
}
int32_t nsAccUtils::GetARIAOrDefaultLevel(const LocalAccessible* aAccessible) {
int32_t level = 0;
nsCoreUtils::GetUIntAttr(aAccessible->GetContent(), nsGkAtoms::aria_level,
&level);
if (level != 0) return level;
return GetDefaultLevel(aAccessible);
}
int32_t nsAccUtils::GetLevelForXULContainerItem(nsIContent* aContent) {
nsCOMPtr<nsIDOMXULContainerItemElement> item =
aContent->AsElement()->AsXULContainerItem();
if (!item) return 0;
nsCOMPtr<dom::Element> containerElement;
item->GetParentContainer(getter_AddRefs(containerElement));
nsCOMPtr<nsIDOMXULContainerElement> container =
containerElement ? containerElement->AsXULContainer() : nullptr;
if (!container) return 0;
// Get level of the item.
int32_t level = -1;
while (container) {
level++;
container->GetParentContainer(getter_AddRefs(containerElement));
container = containerElement ? containerElement->AsXULContainer() : nullptr;
}
return level;
}
void nsAccUtils::SetLiveContainerAttributes(AccAttributes* aAttributes,
nsIContent* aStartContent) {
nsAutoString live, relevant, busy;
dom::Document* doc = aStartContent->GetComposedDoc();
if (!doc) {
return;
}
dom::Element* topEl = doc->GetRootElement();
nsIContent* ancestor = aStartContent;
while (ancestor) {
// container-relevant attribute
if (relevant.IsEmpty() &&
HasDefinedARIAToken(ancestor, nsGkAtoms::aria_relevant) &&
ancestor->AsElement()->GetAttr(kNameSpaceID_None,
nsGkAtoms::aria_relevant, relevant)) {
aAttributes->SetAttributeStringCopy(nsGkAtoms::containerRelevant,
relevant);
}
// container-live, and container-live-role attributes
if (live.IsEmpty()) {
const nsRoleMapEntry* role = nullptr;
if (ancestor->IsElement()) {
role = aria::GetRoleMap(ancestor->AsElement());
}
if (HasDefinedARIAToken(ancestor, nsGkAtoms::aria_live)) {
ancestor->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::aria_live,
live);
} else if (role) {
GetLiveAttrValue(role->liveAttRule, live);
} else if (nsStaticAtom* value = GetAccService()->MarkupAttribute(
ancestor, nsGkAtoms::aria_live)) {
value->ToString(live);
}
if (!live.IsEmpty()) {
aAttributes->SetAttributeStringCopy(nsGkAtoms::containerLive, live);
if (role) {
aAttributes->SetAttribute(nsGkAtoms::containerLiveRole,
role->roleAtom);
}
}
}
// container-atomic attribute
if (ancestor->IsElement() && ancestor->AsElement()->AttrValueIs(
kNameSpaceID_None, nsGkAtoms::aria_atomic,
nsGkAtoms::_true, eCaseMatters)) {
aAttributes->SetAttribute(nsGkAtoms::containerAtomic, true);
}
// container-busy attribute
if (busy.IsEmpty() && HasDefinedARIAToken(ancestor, nsGkAtoms::aria_busy) &&
ancestor->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::aria_busy,
busy)) {
aAttributes->SetAttributeStringCopy(nsGkAtoms::containerBusy, busy);
}
if (ancestor == topEl) {
break;
}
ancestor = ancestor->GetParent();
if (!ancestor) {
ancestor = topEl; // Use <body>/<frameset>
}
}
}
bool nsAccUtils::HasDefinedARIAToken(nsIContent* aContent, nsAtom* aAtom) {
NS_ASSERTION(aContent, "aContent is null in call to HasDefinedARIAToken!");
if (!aContent->IsElement()) return false;
dom::Element* element = aContent->AsElement();
if (!element->HasAttr(kNameSpaceID_None, aAtom) ||
element->AttrValueIs(kNameSpaceID_None, aAtom, nsGkAtoms::_empty,
eCaseMatters) ||
element->AttrValueIs(kNameSpaceID_None, aAtom, nsGkAtoms::_undefined,
eCaseMatters)) {
return false;
}
return true;
}
nsStaticAtom* nsAccUtils::GetARIAToken(dom::Element* aElement, nsAtom* aAttr) {
if (!HasDefinedARIAToken(aElement, aAttr)) return nsGkAtoms::_empty;
static dom::Element::AttrValuesArray tokens[] = {
nsGkAtoms::_false, nsGkAtoms::_true, nsGkAtoms::mixed, nullptr};
int32_t idx =
aElement->FindAttrValueIn(kNameSpaceID_None, aAttr, tokens, eCaseMatters);
if (idx >= 0) return tokens[idx];
return nullptr;
}
nsStaticAtom* nsAccUtils::NormalizeARIAToken(dom::Element* aElement,
nsAtom* aAttr) {
if (!HasDefinedARIAToken(aElement, aAttr)) {
return nsGkAtoms::_empty;
}
if (aAttr == nsGkAtoms::aria_current) {
static dom::Element::AttrValuesArray tokens[] = {
nsGkAtoms::page, nsGkAtoms::step, nsGkAtoms::location_,
nsGkAtoms::date, nsGkAtoms::time, nsGkAtoms::_true,
nullptr};
int32_t idx = aElement->FindAttrValueIn(kNameSpaceID_None, aAttr, tokens,
eCaseMatters);
// If the token is present, return it, otherwise TRUE as per spec.
return (idx >= 0) ? tokens[idx] : nsGkAtoms::_true;
}
return nullptr;
}
LocalAccessible* nsAccUtils::GetSelectableContainer(
LocalAccessible* aAccessible, uint64_t aState) {
if (!aAccessible) return nullptr;
if (!(aState & states::SELECTABLE)) return nullptr;
LocalAccessible* parent = aAccessible;
while ((parent = parent->LocalParent()) && !parent->IsSelect()) {
if (parent->Role() == roles::PANE) return nullptr;
}
return parent;
}
bool nsAccUtils::IsDOMAttrTrue(const LocalAccessible* aAccessible,
nsAtom* aAttr) {
dom::Element* el = aAccessible->Elm();
return el && el->AttrValueIs(kNameSpaceID_None, aAttr, nsGkAtoms::_true,
eCaseMatters);
}
LocalAccessible* nsAccUtils::TableFor(LocalAccessible* aRow) {
if (aRow) {
LocalAccessible* table = aRow->LocalParent();
if (table) {
roles::Role tableRole = table->Role();
const nsRoleMapEntry* roleMapEntry = table->ARIARoleMap();
if (tableRole == roles::GROUPING || // if there's a rowgroup.
(table->IsGenericHyperText() && !roleMapEntry &&
!table->IsTable())) { // or there is a wrapping text container
table = table->LocalParent();
if (table) tableRole = table->Role();
}
return (tableRole == roles::TABLE || tableRole == roles::TREE_TABLE ||
tableRole == roles::MATHML_TABLE)
? table
: nullptr;
}
}
return nullptr;
}
HyperTextAccessible* nsAccUtils::GetTextContainer(nsINode* aNode) {
// Get text accessible containing the result node.
DocAccessible* doc = GetAccService()->GetDocAccessible(aNode->OwnerDoc());
LocalAccessible* accessible =
doc ? doc->GetAccessibleOrContainer(aNode) : nullptr;
if (!accessible) return nullptr;
do {
HyperTextAccessible* textAcc = accessible->AsHyperText();
if (textAcc) return textAcc;
accessible = accessible->LocalParent();
} while (accessible);
return nullptr;
}
nsIntPoint nsAccUtils::ConvertToScreenCoords(int32_t aX, int32_t aY,
uint32_t aCoordinateType,
LocalAccessible* aAccessible) {
nsIntPoint coords(aX, aY);
switch (aCoordinateType) {
case nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE:
break;
case nsIAccessibleCoordinateType::COORDTYPE_WINDOW_RELATIVE: {
coords += nsCoreUtils::GetScreenCoordsForWindow(aAccessible->GetNode());
break;
}
case nsIAccessibleCoordinateType::COORDTYPE_PARENT_RELATIVE: {
coords += GetScreenCoordsForParent(aAccessible);
break;
}
default:
MOZ_ASSERT_UNREACHABLE("invalid coord type!");
}
return coords;
}
void nsAccUtils::ConvertScreenCoordsTo(int32_t* aX, int32_t* aY,
uint32_t aCoordinateType,
LocalAccessible* aAccessible) {
switch (aCoordinateType) {
case nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE:
break;
case nsIAccessibleCoordinateType::COORDTYPE_WINDOW_RELATIVE: {
nsIntPoint coords =
nsCoreUtils::GetScreenCoordsForWindow(aAccessible->GetNode());
*aX -= coords.x;
*aY -= coords.y;
break;
}
case nsIAccessibleCoordinateType::COORDTYPE_PARENT_RELATIVE: {
nsIntPoint coords = GetScreenCoordsForParent(aAccessible);
*aX -= coords.x;
*aY -= coords.y;
break;
}
default:
MOZ_ASSERT_UNREACHABLE("invalid coord type!");
}
}
nsIntPoint nsAccUtils::GetScreenCoordsForParent(LocalAccessible* aAccessible) {
LocalAccessible* parent = aAccessible->LocalParent();
if (!parent) return nsIntPoint(0, 0);
nsIFrame* parentFrame = parent->GetFrame();
if (!parentFrame) return nsIntPoint(0, 0);
nsRect rect = parentFrame->GetScreenRectInAppUnits();
return nsPoint(rect.X(), rect.Y())
.ToNearestPixels(parentFrame->PresContext()->AppUnitsPerDevPixel());
}
bool nsAccUtils::GetLiveAttrValue(uint32_t aRule, nsAString& aValue) {
switch (aRule) {
case eOffLiveAttr:
aValue = u"off"_ns;
return true;
case ePoliteLiveAttr:
aValue = u"polite"_ns;
return true;
case eAssertiveLiveAttr:
aValue = u"assertive"_ns;
return true;
}
return false;
}
#ifdef DEBUG
bool nsAccUtils::IsTextInterfaceSupportCorrect(LocalAccessible* aAccessible) {
// Don't test for accessible docs, it makes us create accessibles too
// early and fire mutation events before we need to
if (aAccessible->IsDoc()) return true;
bool foundText = false;
uint32_t childCount = aAccessible->ChildCount();
for (uint32_t childIdx = 0; childIdx < childCount; childIdx++) {
LocalAccessible* child = aAccessible->LocalChildAt(childIdx);
if (child && child->IsText()) {
foundText = true;
break;
}
}
return !foundText || aAccessible->IsHyperText();
}
#endif
uint32_t nsAccUtils::TextLength(Accessible* aAccessible) {
if (!aAccessible->IsText()) {
return 1;
}
if (LocalAccessible* localAcc = aAccessible->AsLocal()) {
TextLeafAccessible* textLeaf = localAcc->AsTextLeaf();
if (textLeaf) {
return textLeaf->Text().Length();
}
} else if (aAccessible->IsText()) {
MOZ_ASSERT(StaticPrefs::accessibility_cache_enabled_AtStartup(),
"Shouldn't be called on a RemoteAccessible unless the cache is "
"enabled");
RemoteAccessible* remoteAcc = aAccessible->AsRemote();
MOZ_ASSERT(remoteAcc);
return remoteAcc->GetCachedTextLength();
}
// For list bullets (or anything other accessible which would compute its own
// text. They don't have their own frame.
// XXX In the future, list bullets may have frame and anon content, so
// we should be able to remove this at that point
nsAutoString text;
aAccessible->AppendTextTo(text); // Get all the text
return text.Length();
}
bool nsAccUtils::MustPrune(Accessible* aAccessible) {
MOZ_ASSERT(aAccessible);
roles::Role role = aAccessible->Role();
if (role == roles::SLIDER) {
// Always prune the tree for sliders, as it doesn't make sense for a
// slider to have descendants and this confuses NVDA.
return true;
}
if (role != roles::MENUITEM && role != roles::COMBOBOX_OPTION &&
role != roles::OPTION && role != roles::ENTRY &&
role != roles::FLAT_EQUATION && role != roles::PASSWORD_TEXT &&
role != roles::PUSHBUTTON && role != roles::TOGGLE_BUTTON &&
role != roles::GRAPHIC && role != roles::PROGRESSBAR &&
role != roles::SEPARATOR) {
// If it doesn't match any of these roles, don't prune its children.
return false;
}
if (aAccessible->ChildCount() != 1) {
// If the accessible has more than one child, don't prune it.
return false;
}
roles::Role childRole = aAccessible->FirstChild()->Role();
// If the accessible's child is a text leaf, prune the accessible.
return childRole == roles::TEXT_LEAF || childRole == roles::STATICTEXT;
}
bool nsAccUtils::IsARIALive(const LocalAccessible* aAccessible) {
// Get computed aria-live property based on the closest container with the
// attribute. Inner nodes override outer nodes within the same
// document.
// This should be the same as the container-live attribute, but we don't need
// the other container-* attributes, so we can't use the same function.
nsIContent* ancestor = aAccessible->GetContent();
if (!ancestor) {
return false;
}
dom::Document* doc = ancestor->GetComposedDoc();
if (!doc) {
return false;
}
dom::Element* topEl = doc->GetRootElement();
while (ancestor) {
const nsRoleMapEntry* role = nullptr;
if (ancestor->IsElement()) {
role = aria::GetRoleMap(ancestor->AsElement());
}
nsAutoString live;
if (HasDefinedARIAToken(ancestor, nsGkAtoms::aria_live)) {
ancestor->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::aria_live,
live);
} else if (role) {
GetLiveAttrValue(role->liveAttRule, live);
} else if (nsStaticAtom* value = GetAccService()->MarkupAttribute(
ancestor, nsGkAtoms::aria_live)) {
value->ToString(live);
}
if (!live.IsEmpty() && !live.EqualsLiteral("off")) {
return true;
}
if (ancestor == topEl) {
break;
}
ancestor = ancestor->GetParent();
if (!ancestor) {
ancestor = topEl; // Use <body>/<frameset>
}
}
return false;
}