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/*
* Copyright (C) 2008 Nuanti Ltd.
* Copyright (C) 2009 Jan Alonzo
* Copyright (C) 2009, 2010, 2012 Igalia S.L.
*
* Portions from Mozilla a11y, copyright as follows:
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Sun Microsystems, Inc.
* Portions created by the Initial Developer are Copyright (C) 2002
* the Initial Developer. All Rights Reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "WebKitAccessibleUtil.h"
#if ENABLE(ACCESSIBILITY)
#include "AXObjectCache.h"
#include "AccessibilityObject.h"
#include "FrameView.h"
#include "IntRect.h"
#include "Node.h"
#include "Range.h"
#include "RenderObject.h"
#include "TextIterator.h"
#include "VisibleSelection.h"
#include <wtf/text/AtomString.h>
#include <wtf/text/CString.h>
using namespace WebCore;
AtkAttributeSet* addToAtkAttributeSet(AtkAttributeSet* attributeSet, const char* name, const char* value)
{
AtkAttribute* attribute = static_cast<AtkAttribute*>(g_malloc(sizeof(AtkAttribute)));
attribute->name = g_strdup(name);
attribute->value = g_strdup(value);
attributeSet = g_slist_prepend(attributeSet, attribute);
return attributeSet;
}
void contentsRelativeToAtkCoordinateType(AccessibilityObject* coreObject, AtkCoordType coordType, IntRect rect, gint* x, gint* y, gint* width, gint* height)
{
FrameView* frameView = coreObject->documentFrameView();
if (frameView) {
switch (coordType) {
case ATK_XY_WINDOW:
rect = frameView->contentsToWindow(rect);
break;
case ATK_XY_SCREEN:
rect = frameView->contentsToScreen(rect);
break;
#if ATK_CHECK_VERSION(2, 30, 0)
case ATK_XY_PARENT:
RELEASE_ASSERT_NOT_REACHED();
#endif
}
}
if (x)
*x = rect.x();
if (y)
*y = rect.y();
if (width)
*width = rect.width();
if (height)
*height = rect.height();
}
// FIXME: Different kinds of elements are putting the title tag to use
// in different AX fields. This might not be 100% correct but we will
// keep it now in order to achieve consistency with previous behavior.
static bool titleTagShouldBeUsedInDescriptionField(AccessibilityObject* coreObject)
{
return (coreObject->isLink() && !coreObject->isImageMapLink()) || coreObject->isImage();
}
// This should be the "visible" text that's actually on the screen if possible.
// If there's alternative text, that can override the title.
String accessibilityTitle(AccessibilityObject* coreObject)
{
Vector<AccessibilityText> textOrder;
coreObject->accessibilityText(textOrder);
for (const AccessibilityText& text : textOrder) {
// Once we encounter visible text, or the text from our children that should be used foremost.
if (text.textSource == AccessibilityTextSource::Visible || text.textSource == AccessibilityTextSource::Children)
return text.text;
// If there's an element that labels this object and it's not exposed, then we should use
// that text as our title.
if (text.textSource == AccessibilityTextSource::LabelByElement && !coreObject->exposesTitleUIElement())
return text.text;
// Elements of role AccessibilityRole::Toolbar will return its title as AccessibilityTextSource::Alternative.
if (coreObject->roleValue() == AccessibilityRole::Toolbar && text.textSource == AccessibilityTextSource::Alternative)
return text.text;
// FIXME: The title tag is used in certain cases for the title. This usage should
// probably be in the description field since it's not "visible".
if (text.textSource == AccessibilityTextSource::TitleTag && !titleTagShouldBeUsedInDescriptionField(coreObject))
return text.text;
}
return String();
}
String accessibilityDescription(AccessibilityObject* coreObject)
{
Vector<AccessibilityText> textOrder;
coreObject->accessibilityText(textOrder);
bool visibleTextAvailable = false;
for (const AccessibilityText& text : textOrder) {
if (text.textSource == AccessibilityTextSource::Alternative)
return text.text;
switch (text.textSource) {
case AccessibilityTextSource::Visible:
case AccessibilityTextSource::Children:
case AccessibilityTextSource::LabelByElement:
visibleTextAvailable = true;
default:
break;
}
if (text.textSource == AccessibilityTextSource::TitleTag && !visibleTextAvailable)
return text.text;
}
return String();
}
bool selectionBelongsToObject(AccessibilityObject* coreObject, VisibleSelection& selection)
{
if (!coreObject || !coreObject->isAccessibilityRenderObject())
return false;
if (selection.isNone())
return false;
RefPtr<Range> range = selection.toNormalizedRange();
if (!range)
return false;
// We want to check that both the selection intersects the node
// AND that the selection is not just "touching" one of the
// boundaries for the selected node. We want to check whether the
// node is actually inside the region, at least partially.
auto& node = *coreObject->node();
auto* lastDescendant = node.lastDescendant();
unsigned lastOffset = lastOffsetInNode(lastDescendant);
auto intersectsResult = range->intersectsNode(node);
return !intersectsResult.hasException()
&& intersectsResult.releaseReturnValue()
&& (&range->endContainer() != &node || range->endOffset())
&& (&range->startContainer() != lastDescendant || range->startOffset() != lastOffset);
}
AXCoreObject* objectFocusedAndCaretOffsetUnignored(AXCoreObject* referenceObject, int& offset)
{
// Indication that something bogus has transpired.
offset = -1;
Document* document = referenceObject->document();
if (!document)
return nullptr;
Node* focusedNode = referenceObject->selection().end().containerNode();
if (!focusedNode)
return nullptr;
RenderObject* focusedRenderer = focusedNode->renderer();
if (!focusedRenderer)
return nullptr;
AccessibilityObject* focusedObject = document->axObjectCache()->getOrCreate(focusedRenderer);
if (!focusedObject)
return nullptr;
// Look for the actual (not ignoring accessibility) selected object.
AXCoreObject* firstUnignoredParent = focusedObject;
if (firstUnignoredParent->accessibilityIsIgnored())
firstUnignoredParent = firstUnignoredParent->parentObjectUnignored();
if (!firstUnignoredParent)
return nullptr;
// Don't ignore links if the offset is being requested for a link
// or if the link is a block.
if (!referenceObject->isLink() && firstUnignoredParent->isLink()
&& !(firstUnignoredParent->renderer() && !firstUnignoredParent->renderer()->isInline()))
firstUnignoredParent = firstUnignoredParent->parentObjectUnignored();
if (!firstUnignoredParent)
return nullptr;
// The reference object must either coincide with the focused
// object being considered, or be a descendant of it.
if (referenceObject->isDescendantOfObject(firstUnignoredParent))
referenceObject = firstUnignoredParent;
Node* startNode = nullptr;
if (firstUnignoredParent != referenceObject || firstUnignoredParent->isTextControl()) {
// We need to use the first child's node of the reference
// object as the start point to calculate the caret offset
// because we want it to be relative to the object of
// reference, not just to the focused object (which could have
// previous siblings which should be taken into account too).
AXCoreObject* axFirstChild = referenceObject->firstChild();
if (axFirstChild)
startNode = axFirstChild->node();
}
// Getting the Position of a PseudoElement now triggers an assertion.
// This can occur when clicking on empty space in a render block.
if (!startNode || startNode->isPseudoElement())
startNode = firstUnignoredParent->node();
// Check if the node for the first parent object not ignoring
// accessibility is null again before using it. This might happen
// with certain kind of accessibility objects, such as the root
// one (the scroller containing the webArea object).
if (!startNode)
return nullptr;
VisiblePosition startPosition = VisiblePosition(positionBeforeNode(startNode), DOWNSTREAM);
VisiblePosition endPosition = firstUnignoredParent->selection().visibleEnd();
if (startPosition == endPosition)
offset = 0;
else if (!isStartOfLine(endPosition)) {
RefPtr<Range> range = makeRange(startPosition, endPosition.previous());
offset = (range ? characterCount(*range, TextIteratorEmitsCharactersBetweenAllVisiblePositions) : 0) + 1;
} else {
RefPtr<Range> range = makeRange(startPosition, endPosition);
offset = range ? characterCount(*range, TextIteratorEmitsCharactersBetweenAllVisiblePositions) : 0;
}
return firstUnignoredParent;
}
#endif