michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "AccGroupInfo.h"
michael@0: #include "nsAccUtils.h"
michael@0: 
michael@0: #include "Role.h"
michael@0: #include "States.h"
michael@0: 
michael@0: using namespace mozilla::a11y;
michael@0: 
michael@0: AccGroupInfo::AccGroupInfo(Accessible* aItem, role aRole) :
michael@0:   mPosInSet(0), mSetSize(0), mParent(nullptr), mItem(aItem), mRole(aRole)
michael@0: {
michael@0:   MOZ_COUNT_CTOR(AccGroupInfo);
michael@0:   Update();
michael@0: }
michael@0: 
michael@0: void
michael@0: AccGroupInfo::Update()
michael@0: {
michael@0:   Accessible* parent = mItem->Parent();
michael@0:   if (!parent)
michael@0:     return;
michael@0: 
michael@0:   int32_t indexInParent = mItem->IndexInParent();
michael@0:   uint32_t siblingCount = parent->ChildCount();
michael@0:   if (indexInParent == -1 ||
michael@0:       indexInParent >= static_cast<int32_t>(siblingCount)) {
michael@0:     NS_ERROR("Wrong index in parent! Tree invalidation problem.");
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   int32_t level = nsAccUtils::GetARIAOrDefaultLevel(mItem);
michael@0: 
michael@0:   // Compute position in set.
michael@0:   mPosInSet = 1;
michael@0:   for (int32_t idx = indexInParent - 1; idx >= 0 ; idx--) {
michael@0:     Accessible* sibling = parent->GetChildAt(idx);
michael@0:     roles::Role siblingRole = sibling->Role();
michael@0: 
michael@0:     // If the sibling is separator then the group is ended.
michael@0:     if (siblingRole == roles::SEPARATOR)
michael@0:       break;
michael@0: 
michael@0:     // If sibling is not visible and hasn't the same base role.
michael@0:     if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE)
michael@0:       continue;
michael@0: 
michael@0:     // Check if it's hierarchical flatten structure, i.e. if the sibling
michael@0:     // level is lesser than this one then group is ended, if the sibling level
michael@0:     // is greater than this one then the group is split by some child elements
michael@0:     // (group will be continued).
michael@0:     int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling);
michael@0:     if (siblingLevel < level) {
michael@0:       mParent = sibling;
michael@0:       break;
michael@0:     }
michael@0: 
michael@0:     // Skip subset.
michael@0:     if (siblingLevel > level)
michael@0:       continue;
michael@0: 
michael@0:     // If the previous item in the group has calculated group information then
michael@0:     // build group information for this item based on found one.
michael@0:     if (sibling->mGroupInfo) {
michael@0:       mPosInSet += sibling->mGroupInfo->mPosInSet;
michael@0:       mParent = sibling->mGroupInfo->mParent;
michael@0:       mSetSize = sibling->mGroupInfo->mSetSize;
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     mPosInSet++;
michael@0:   }
michael@0: 
michael@0:   // Compute set size.
michael@0:   mSetSize = mPosInSet;
michael@0: 
michael@0:   for (uint32_t idx = indexInParent + 1; idx < siblingCount; idx++) {
michael@0:     Accessible* sibling = parent->GetChildAt(idx);
michael@0: 
michael@0:     roles::Role siblingRole = sibling->Role();
michael@0: 
michael@0:     // If the sibling is separator then the group is ended.
michael@0:     if (siblingRole == roles::SEPARATOR)
michael@0:       break;
michael@0: 
michael@0:     // If sibling is visible and has the same base role
michael@0:     if (BaseRole(siblingRole) != mRole || sibling->State() & states::INVISIBLE)
michael@0:       continue;
michael@0: 
michael@0:     // and check if it's hierarchical flatten structure.
michael@0:     int32_t siblingLevel = nsAccUtils::GetARIAOrDefaultLevel(sibling);
michael@0:     if (siblingLevel < level)
michael@0:       break;
michael@0: 
michael@0:     // Skip subset.
michael@0:     if (siblingLevel > level)
michael@0:       continue;
michael@0: 
michael@0:     // If the next item in the group has calculated group information then
michael@0:     // build group information for this item based on found one.
michael@0:     if (sibling->mGroupInfo) {
michael@0:       mParent = sibling->mGroupInfo->mParent;
michael@0:       mSetSize = sibling->mGroupInfo->mSetSize;
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     mSetSize++;
michael@0:   }
michael@0: 
michael@0:   if (mParent)
michael@0:     return;
michael@0: 
michael@0:   roles::Role parentRole = parent->Role();
michael@0:   if (ShouldReportRelations(mRole, parentRole))
michael@0:     mParent = parent;
michael@0: 
michael@0:   // ARIA tree and list can be arranged by using ARIA groups to organize levels.
michael@0:   if (parentRole != roles::GROUPING)
michael@0:     return;
michael@0: 
michael@0:   // Way #1 for ARIA tree (not ARIA treegrid): previous sibling of a group is a
michael@0:   // parent. In other words the parent of the tree item will be a group and
michael@0:   // the previous tree item of the group is a conceptual parent of the tree
michael@0:   // item.
michael@0:   if (mRole == roles::OUTLINEITEM) {
michael@0:     Accessible* parentPrevSibling = parent->PrevSibling();
michael@0:     if (parentPrevSibling && parentPrevSibling->Role() == mRole) {
michael@0:       mParent = parentPrevSibling;
michael@0:       return;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Way #2 for ARIA list and tree: group is a child of an item. In other words
michael@0:   // the parent of the item will be a group and containing item of the group is
michael@0:   // a conceptual parent of the item.
michael@0:   if (mRole == roles::LISTITEM || mRole == roles::OUTLINEITEM) {
michael@0:     Accessible* grandParent = parent->Parent();
michael@0:     if (grandParent && grandParent->Role() == mRole)
michael@0:       mParent = grandParent;
michael@0:   }
michael@0: }
michael@0: 
michael@0: Accessible*
michael@0: AccGroupInfo::FirstItemOf(Accessible* aContainer)
michael@0: {
michael@0:   // ARIA tree can be arranged by ARIA groups case #1 (previous sibling of a
michael@0:   // group is a parent) or by aria-level.
michael@0:   a11y::role containerRole = aContainer->Role();
michael@0:   Accessible* item = aContainer->NextSibling();
michael@0:   if (item) {
michael@0:     if (containerRole == roles::OUTLINEITEM && item->Role() == roles::GROUPING)
michael@0:       item = item->FirstChild();
michael@0: 
michael@0:     if (item) {
michael@0:       AccGroupInfo* itemGroupInfo = item->GetGroupInfo();
michael@0:       if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer)
michael@0:         return item;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // ARIA list and tree can be arranged by ARIA groups case #2 (group is
michael@0:   // a child of an item).
michael@0:   item = aContainer->LastChild();
michael@0:   if (!item)
michael@0:     return nullptr;
michael@0: 
michael@0:   if (item->Role() == roles::GROUPING &&
michael@0:       (containerRole == roles::LISTITEM || containerRole == roles::OUTLINEITEM)) {
michael@0:     item = item->FirstChild();
michael@0:     if (item) {
michael@0:       AccGroupInfo* itemGroupInfo = item->GetGroupInfo();
michael@0:       if (itemGroupInfo && itemGroupInfo->ConceptualParent() == aContainer)
michael@0:         return item;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Otherwise, it can be a direct child if the container is a list or tree.
michael@0:   item = aContainer->FirstChild();
michael@0:   if (ShouldReportRelations(item->Role(), containerRole))
michael@0:     return item;
michael@0: 
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: Accessible*
michael@0: AccGroupInfo::NextItemTo(Accessible* aItem)
michael@0: {
michael@0:   AccGroupInfo* groupInfo = aItem->GetGroupInfo();
michael@0:   if (!groupInfo)
michael@0:     return nullptr;
michael@0: 
michael@0:   // If the item in middle of the group then search next item in siblings.
michael@0:   if (groupInfo->PosInSet() >= groupInfo->SetSize())
michael@0:     return nullptr;
michael@0: 
michael@0:   Accessible* parent = aItem->Parent();
michael@0:   uint32_t childCount = parent->ChildCount();
michael@0:   for (int32_t idx = aItem->IndexInParent() + 1; idx < childCount; idx++) {
michael@0:     Accessible* nextItem = parent->GetChildAt(idx);
michael@0:     AccGroupInfo* nextGroupInfo = nextItem->GetGroupInfo();
michael@0:     if (nextGroupInfo &&
michael@0:         nextGroupInfo->ConceptualParent() == groupInfo->ConceptualParent()) {
michael@0:       return nextItem;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   NS_NOTREACHED("Item in the middle of the group but there's no next item!");
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: bool
michael@0: AccGroupInfo::ShouldReportRelations(role aRole, role aParentRole)
michael@0: {
michael@0:   // We only want to report hierarchy-based node relations for items in tree or
michael@0:   // list form.  ARIA level/owns relations are always reported.
michael@0:   if (aParentRole == roles::OUTLINE && aRole == roles::OUTLINEITEM)
michael@0:     return true;
michael@0:   if (aParentRole == roles::TREE_TABLE && aRole == roles::ROW)
michael@0:     return true;
michael@0:   if (aParentRole == roles::LIST && aRole == roles::LISTITEM)
michael@0:     return true;
michael@0: 
michael@0:   return false;
michael@0: }