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/* 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
#include "AccGroupInfo.h"
#include "mozilla/a11y/Accessible.h"
#include "mozilla/a11y/TableAccessible.h"
#include "nsAccUtils.h"
#include "nsIAccessiblePivot.h"
#include "Pivot.h"
#include "States.h"
using namespace mozilla::a11y;
static role BaseRole(role aRole);
// This rule finds candidate siblings for compound widget children.
class CompoundWidgetSiblingRule : public PivotRule {
public:
CompoundWidgetSiblingRule() = delete;
explicit CompoundWidgetSiblingRule(role aRole) : mRole(aRole) {}
uint16_t Match(Accessible* aAcc) override {
// If the acc has a matching role, that's a valid sibling. If the acc is
// separator then the group is ended. Return a match for separators with
// the assumption that the caller will check for the role of the returned
// accessible.
const role accRole = aAcc->Role();
if (BaseRole(accRole) == mRole || accRole == role::SEPARATOR) {
return nsIAccessibleTraversalRule::FILTER_MATCH |
nsIAccessibleTraversalRule::FILTER_IGNORE_SUBTREE;
}
// Ignore generic accessibles, but keep searching through the subtree for
// siblings.
if (aAcc->IsGeneric()) {
return nsIAccessibleTraversalRule::FILTER_IGNORE;
}
return nsIAccessibleTraversalRule::FILTER_IGNORE_SUBTREE;
}
private:
role mRole = role::NOTHING;
};
AccGroupInfo::AccGroupInfo(const Accessible* aItem, role aRole)
: mPosInSet(0), mSetSize(0), mParentId(0), mItem(aItem), mRole(aRole) {
MOZ_COUNT_CTOR(AccGroupInfo);
Update();
}
void AccGroupInfo::Update() {
mParentId = 0;
Accessible* parent = mItem->GetNonGenericParent();
if (!parent) {
return;
}
const int32_t level = GetARIAOrDefaultLevel(mItem);
// Compute position in set.
mPosInSet = 1;
// Search backwards through the tree for candidate siblings.
Accessible* candidateSibling = const_cast<Accessible*>(mItem);
Pivot pivot{parent};
CompoundWidgetSiblingRule widgetSiblingRule{mRole};
while ((candidateSibling = pivot.Prev(candidateSibling, widgetSiblingRule)) &&
candidateSibling != parent) {
// If the sibling is separator then the group is ended.
if (candidateSibling->Role() == roles::SEPARATOR) {
break;
}
const AccGroupInfo* siblingGroupInfo = candidateSibling->GetGroupInfo();
// Skip invisible siblings.
// If the sibling has calculated group info, that means it's visible.
if (!siblingGroupInfo && candidateSibling->State() & states::INVISIBLE) {
continue;
}
// Check if it's hierarchical flatten structure, i.e. if the sibling
// level is lesser than this one then group is ended, if the sibling level
// is greater than this one then the group is split by some child elements
// (group will be continued).
const int32_t siblingLevel = GetARIAOrDefaultLevel(candidateSibling);
if (siblingLevel < level) {
mParentId = candidateSibling->ID();
break;
}
// Skip subset.
if (siblingLevel > level) {
continue;
}
// If the previous item in the group has calculated group information then
// build group information for this item based on found one.
if (siblingGroupInfo) {
mPosInSet += siblingGroupInfo->mPosInSet;
mParentId = siblingGroupInfo->mParentId;
mSetSize = siblingGroupInfo->mSetSize;
return;
}
mPosInSet++;
}
// Compute set size.
mSetSize = mPosInSet;
candidateSibling = const_cast<Accessible*>(mItem);
while ((candidateSibling = pivot.Next(candidateSibling, widgetSiblingRule)) &&
candidateSibling != parent) {
// If the sibling is separator then the group is ended.
if (candidateSibling->Role() == roles::SEPARATOR) {
break;
}
const AccGroupInfo* siblingGroupInfo = candidateSibling->GetGroupInfo();
// Skip invisible siblings.
// If the sibling has calculated group info, that means it's visible.
if (!siblingGroupInfo && candidateSibling->State() & states::INVISIBLE) {
continue;
}
// and check if it's hierarchical flatten structure.
const int32_t siblingLevel = GetARIAOrDefaultLevel(candidateSibling);
if (siblingLevel < level) {
break;
}
// Skip subset.
if (siblingLevel > level) {
continue;
}
// If the next item in the group has calculated group information then
// build group information for this item based on found one.
if (siblingGroupInfo) {
mParentId = siblingGroupInfo->mParentId;
mSetSize = siblingGroupInfo->mSetSize;
return;
}
mSetSize++;
}
if (mParentId) {
return;
}
roles::Role parentRole = parent->Role();
if (ShouldReportRelations(mRole, parentRole)) {
mParentId = parent->ID();
}
// ARIA tree and list can be arranged by using ARIA groups to organize levels.
if (parentRole != roles::GROUPING) {
return;
}
// Way #1 for ARIA tree (not ARIA treegrid): previous sibling of a group is a
// parent. In other words the parent of the tree item will be a group and
// the previous tree item of the group is a conceptual parent of the tree
// item.
if (mRole == roles::OUTLINEITEM) {
// Find the relevant grandparent of the item. Use that parent as the root
// and find the previous outline item sibling within that root.
Accessible* grandParent = parent->GetNonGenericParent();
MOZ_ASSERT(grandParent);
Pivot pivot{grandParent};
CompoundWidgetSiblingRule parentSiblingRule{mRole};
Accessible* parentPrevSibling = pivot.Prev(parent, widgetSiblingRule);
if (parentPrevSibling && parentPrevSibling->Role() == mRole) {
mParentId = parentPrevSibling->ID();
return;
}
}
// Way #2 for ARIA list and tree: group is a child of an item. In other words
// the parent of the item will be a group and containing item of the group is
// a conceptual parent of the item.
if (mRole == roles::LISTITEM || mRole == roles::OUTLINEITEM) {
Accessible* grandParent = parent->GetNonGenericParent();
if (grandParent && grandParent->Role() == mRole) {
mParentId = grandParent->ID();
}
}
}
AccGroupInfo* AccGroupInfo::CreateGroupInfo(const Accessible* aAccessible) {
mozilla::a11y::role role = aAccessible->Role();
if (role != mozilla::a11y::roles::ROW &&
role != mozilla::a11y::roles::OUTLINEITEM &&
role != mozilla::a11y::roles::OPTION &&
role != mozilla::a11y::roles::LISTITEM &&
role != mozilla::a11y::roles::MENUITEM &&
role != mozilla::a11y::roles::COMBOBOX_OPTION &&
role != mozilla::a11y::roles::RICH_OPTION &&
role != mozilla::a11y::roles::CHECK_RICH_OPTION &&
role != mozilla::a11y::roles::PARENT_MENUITEM &&
role != mozilla::a11y::roles::CHECK_MENU_ITEM &&
role != mozilla::a11y::roles::RADIO_MENU_ITEM &&
role != mozilla::a11y::roles::RADIOBUTTON &&
role != mozilla::a11y::roles::PAGETAB &&
role != mozilla::a11y::roles::COMMENT) {
return nullptr;
}
AccGroupInfo* info = new AccGroupInfo(aAccessible, BaseRole(role));
return info;
}
Accessible* AccGroupInfo::FirstItemOf(const Accessible* aContainer) {
// ARIA tree can be arranged by ARIA groups case #1 (previous sibling of a
// group is a parent) or by aria-level.
a11y::role containerRole = aContainer->Role();
Accessible* item = aContainer->NextSibling();
if (item) {
if (containerRole == roles::OUTLINEITEM &&
item->Role() == roles::GROUPING) {
item = item->FirstChild();
}
if (item) {
AccGroupInfo* itemGroupInfo = item->GetOrCreateGroupInfo();
if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer) {
return item;
}
}
}
// ARIA list and tree can be arranged by ARIA groups case #2 (group is
// a child of an item).
item = aContainer->LastChild();
if (!item) return nullptr;
if (item->Role() == roles::GROUPING &&
(containerRole == roles::LISTITEM ||
containerRole == roles::OUTLINEITEM)) {
item = item->FirstChild();
if (item) {
AccGroupInfo* itemGroupInfo = item->GetOrCreateGroupInfo();
if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer) {
return item;
}
}
}
// Otherwise, it can be a direct child if the container is a list or tree.
item = aContainer->FirstChild();
if (ShouldReportRelations(item->Role(), containerRole)) return item;
return nullptr;
}
uint32_t AccGroupInfo::TotalItemCount(Accessible* aContainer,
bool* aIsHierarchical) {
uint32_t itemCount = 0;
switch (aContainer->Role()) {
case roles::GRID:
case roles::TABLE:
if (auto val = aContainer->GetIntARIAAttr(nsGkAtoms::aria_rowcount)) {
if (*val >= 0) {
return *val;
}
}
if (TableAccessible* tableAcc = aContainer->AsTable()) {
return tableAcc->RowCount();
}
break;
case roles::ROW:
if (Accessible* table = nsAccUtils::TableFor(aContainer)) {
if (auto val = table->GetIntARIAAttr(nsGkAtoms::aria_colcount)) {
if (*val >= 0) {
return *val;
}
}
if (TableAccessible* tableAcc = table->AsTable()) {
return tableAcc->ColCount();
}
}
break;
case roles::OUTLINE:
case roles::LIST:
case roles::MENUBAR:
case roles::MENUPOPUP:
case roles::COMBOBOX:
case roles::GROUPING:
case roles::ROWGROUP:
case roles::TREE_TABLE:
case roles::COMBOBOX_LIST:
case roles::LISTBOX:
case roles::DEFINITION_LIST:
case roles::EDITCOMBOBOX:
case roles::RADIO_GROUP:
case roles::PAGETABLIST: {
Accessible* childItem = AccGroupInfo::FirstItemOf(aContainer);
if (!childItem) {
childItem = aContainer->FirstChild();
if (childItem && childItem->IsTextLeaf()) {
// First child can be a text leaf, check its sibling for an item.
childItem = childItem->NextSibling();
}
}
if (childItem) {
GroupPos groupPos = childItem->GroupPosition();
itemCount = groupPos.setSize;
if (groupPos.level && aIsHierarchical) {
*aIsHierarchical = true;
}
}
break;
}
default:
break;
}
return itemCount;
}
Accessible* AccGroupInfo::NextItemTo(Accessible* aItem) {
AccGroupInfo* groupInfo = aItem->GetOrCreateGroupInfo();
if (!groupInfo) return nullptr;
// If the item in middle of the group then search next item in siblings.
if (groupInfo->PosInSet() >= groupInfo->SetSize()) return nullptr;
Accessible* parent = aItem->Parent();
uint32_t childCount = parent->ChildCount();
for (uint32_t idx = aItem->IndexInParent() + 1; idx < childCount; idx++) {
Accessible* nextItem = parent->ChildAt(idx);
AccGroupInfo* nextGroupInfo = nextItem->GetOrCreateGroupInfo();
if (nextGroupInfo &&
nextGroupInfo->ConceptualParent() == groupInfo->ConceptualParent()) {
return nextItem;
}
}
MOZ_ASSERT_UNREACHABLE(
"Item in the middle of the group but there's no next item!");
return nullptr;
}
size_t AccGroupInfo::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) {
// We don't count mParentId or mItem since they (should be) counted
// as part of the document.
return aMallocSizeOf(this);
}
bool AccGroupInfo::ShouldReportRelations(role aRole, role aParentRole) {
// We only want to report hierarchy-based node relations for items in tree or
// list form. ARIA level/owns relations are always reported.
if (aParentRole == roles::OUTLINE && aRole == roles::OUTLINEITEM) return true;
if (aParentRole == roles::TREE_TABLE && aRole == roles::ROW) return true;
if (aParentRole == roles::LIST && aRole == roles::LISTITEM) return true;
return false;
}
int32_t AccGroupInfo::GetARIAOrDefaultLevel(const Accessible* aAccessible) {
int32_t level = 0;
aAccessible->ARIAGroupPosition(&level, nullptr, nullptr);
if (level != 0) return level;
return aAccessible->GetLevel(true);
}
Accessible* AccGroupInfo::ConceptualParent() const {
if (!mParentId) {
// The conceptual parent can never be the document, so id 0 means none.
return nullptr;
}
if (Accessible* doc =
nsAccUtils::DocumentFor(const_cast<Accessible*>(mItem))) {
return nsAccUtils::GetAccessibleByID(doc, mParentId);
}
return nullptr;
}
static role BaseRole(role aRole) {
if (aRole == roles::CHECK_MENU_ITEM || aRole == roles::PARENT_MENUITEM ||
aRole == roles::RADIO_MENU_ITEM) {
return roles::MENUITEM;
}
if (aRole == roles::CHECK_RICH_OPTION) {
return roles::RICH_OPTION;
}
return aRole;
}