accessibilityobjectwrapper.mm

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        }
        return m_object->accessibilityDescription();
    }
    
    if ([attributeName isEqualToString: NSAccessibilityValueAttribute]) {
        if (m_object->isAttachment()) {
            if ([[[self attachmentView] accessibilityAttributeNames] containsObject:NSAccessibilityValueAttribute]) 
                return [[self attachmentView] accessibilityAttributeValue:NSAccessibilityValueAttribute];
        }
        if (m_object->isProgressIndicator() || m_object->isSlider())
            return [NSNumber numberWithFloat:m_object->valueForRange()];
        if (m_object->hasIntValue())
            return [NSNumber numberWithInt:m_object->intValue()];
        return m_object->stringValue();
    }

    if ([attributeName isEqualToString: NSAccessibilityMinValueAttribute])
        return [NSNumber numberWithFloat:m_object->minValueForRange()];

    if ([attributeName isEqualToString: NSAccessibilityMaxValueAttribute])
        return [NSNumber numberWithFloat:m_object->maxValueForRange()];

    if ([attributeName isEqualToString: NSAccessibilityHelpAttribute])
        return m_object->helpText();

    if ([attributeName isEqualToString: NSAccessibilityFocusedAttribute])
        return [NSNumber numberWithBool: m_object->isFocused()];

    if ([attributeName isEqualToString: NSAccessibilityEnabledAttribute])
        return [NSNumber numberWithBool: m_object->isEnabled()];

    if ([attributeName isEqualToString: NSAccessibilitySizeAttribute]) {
        IntSize s = m_object->size();
        return [NSValue valueWithSize: NSMakeSize(s.width(), s.height())];
    }

    if ([attributeName isEqualToString: NSAccessibilityPositionAttribute])
        return [self position];

    if ([attributeName isEqualToString: NSAccessibilityWindowAttribute] ||
        [attributeName isEqualToString: NSAccessibilityTopLevelUIElementAttribute]) {
        FrameView* fv = m_object->documentFrameView();
        if (fv)
            return [fv->platformWidget() window];
        return nil;
    }
    
    if ([attributeName isEqualToString:NSAccessibilityAccessKeyAttribute]) {
        AtomicString accessKey = m_object->accessKey();
        if (accessKey.isNull())
            return nil;
        return accessKey;
    }
    
    if (m_object->isDataTable()) {
        // TODO: distinguish between visible and non-visible rows
        if ([attributeName isEqualToString:NSAccessibilityRowsAttribute] || 
            [attributeName isEqualToString:NSAccessibilityVisibleRowsAttribute]) {
            return convertToNSArray(static_cast<AccessibilityTable*>(m_object)->rows());
        }
        // TODO: distinguish between visible and non-visible columns
        if ([attributeName isEqualToString:NSAccessibilityColumnsAttribute] || 
            [attributeName isEqualToString:NSAccessibilityVisibleColumnsAttribute]) {
            return convertToNSArray(static_cast<AccessibilityTable*>(m_object)->columns());
        }
        
        // HTML tables don't support these
        if ([attributeName isEqualToString:NSAccessibilitySelectedColumnsAttribute] || 
            [attributeName isEqualToString:NSAccessibilitySelectedRowsAttribute] ||
            [attributeName isEqualToString:NSAccessibilitySelectedCellsAttribute])
            return nil;
        
        if ([attributeName isEqualToString:(NSString *)kAXColumnHeaderUIElementsAttribute]) {
            AccessibilityObject::AccessibilityChildrenVector columnHeaders;
            static_cast<AccessibilityTable*>(m_object)->columnHeaders(columnHeaders);
            return convertToNSArray(columnHeaders);            
        }
        
        if ([attributeName isEqualToString:NSAccessibilityHeaderAttribute]) {
            AccessibilityObject* headerContainer = static_cast<AccessibilityTable*>(m_object)->headerContainer();
            if (headerContainer)
                return headerContainer->wrapper();
            return nil;
        }

        if ([attributeName isEqualToString:NSAccessibilityRowHeaderUIElementsAttribute]) {
            AccessibilityObject::AccessibilityChildrenVector rowHeaders;
            static_cast<AccessibilityTable*>(m_object)->rowHeaders(rowHeaders);
            return convertToNSArray(rowHeaders);                        
        }
        
        if ([attributeName isEqualToString:NSAccessibilityVisibleCellsAttribute]) {
            AccessibilityObject::AccessibilityChildrenVector cells;
            static_cast<AccessibilityTable*>(m_object)->cells(cells);
            return convertToNSArray(cells);
        }        
    }
    
    if (m_object->isTableRow()) {
        if ([attributeName isEqualToString:NSAccessibilityIndexAttribute])
            return [NSNumber numberWithInt:static_cast<AccessibilityTableRow*>(m_object)->rowIndex()];
    }
    
    if (m_object->isTableColumn()) {
        if ([attributeName isEqualToString:NSAccessibilityIndexAttribute])
            return [NSNumber numberWithInt:static_cast<AccessibilityTableColumn*>(m_object)->columnIndex()];
        
        // rows attribute for a column is the list of all the elements in that column at each row
        if ([attributeName isEqualToString:NSAccessibilityRowsAttribute] || 
            [attributeName isEqualToString:NSAccessibilityVisibleRowsAttribute]) {
            return convertToNSArray(static_cast<AccessibilityTableColumn*>(m_object)->children());
        }
        if ([attributeName isEqualToString:NSAccessibilityHeaderAttribute]) {
            AccessibilityObject* header = static_cast<AccessibilityTableColumn*>(m_object)->headerObject();
            if (!header)
                return nil;
            return header->wrapper();
        }
    }
    
    if (m_object->isTableCell()) {
        if ([attributeName isEqualToString:NSAccessibilityRowIndexRangeAttribute]) {
            pair<int, int> rowRange;
            static_cast<AccessibilityTableCell*>(m_object)->rowIndexRange(rowRange);
            return [NSValue valueWithRange:NSMakeRange(rowRange.first, rowRange.second)];
        }  
        if ([attributeName isEqualToString:NSAccessibilityColumnIndexRangeAttribute]) {
            pair<int, int> columnRange;
            static_cast<AccessibilityTableCell*>(m_object)->columnIndexRange(columnRange);
            return [NSValue valueWithRange:NSMakeRange(columnRange.first, columnRange.second)];
        }  
    }
    
    if ((m_object->isListBox() ||m_object->isList()) && [attributeName isEqualToString:NSAccessibilityOrientationAttribute])
        return NSAccessibilityVerticalOrientationValue;

    if ([attributeName isEqualToString: @"AXSelectedTextMarkerRange"])
        return [self textMarkerRangeForSelection];
    
    if (m_object->isAccessibilityRenderObject()) {
        RenderObject* renderer = static_cast<AccessibilityRenderObject*>(m_object)->renderer();
        if (!renderer)
            return nil;
        
        if ([attributeName isEqualToString: @"AXStartTextMarker"])
            return textMarkerForVisiblePosition(startOfDocument(renderer->document()));
        if ([attributeName isEqualToString: @"AXEndTextMarker"])
            return textMarkerForVisiblePosition(endOfDocument(renderer->document()));

        if ([attributeName isEqualToString:NSAccessibilityBlockQuoteLevelAttribute])
            return [NSNumber numberWithInt:blockquoteLevel(renderer)];
    } else {
        if ([attributeName isEqualToString:NSAccessibilityBlockQuoteLevelAttribute]) {
            AccessibilityObject* parent = m_object->parentObjectUnignored();
            if (!parent)
                return [NSNumber numberWithInt:0];
            return [parent->wrapper() accessibilityAttributeValue:NSAccessibilityBlockQuoteLevelAttribute];        
        }
    }
    
    if ([attributeName isEqualToString: NSAccessibilityLinkedUIElementsAttribute]) {
        AccessibilityObject::AccessibilityChildrenVector linkedUIElements;
        m_object->linkedUIElements(linkedUIElements);
        if (linkedUIElements.size() == 0)
            return nil;
        return convertToNSArray(linkedUIElements);
    }

    if ([attributeName isEqualToString: NSAccessibilitySelectedAttribute])
        return [NSNumber numberWithBool:m_object->isSelected()];

    if ([attributeName isEqualToString: NSAccessibilityServesAsTitleForUIElementsAttribute] && m_object->isMenuButton()) {
        AccessibilityObject* uiElement = static_cast<AccessibilityRenderObject*>(m_object)->menuForMenuButton();
        if (uiElement)
            return [NSArray arrayWithObject:uiElement->wrapper()];
    }

    if ([attributeName isEqualToString:NSAccessibilityTitleUIElementAttribute]) {
        AccessibilityObject* obj = m_object->titleUIElement();
        if (obj)
            return obj->wrapper();
        return nil;
    }
    
    return nil;
}

- (id)accessibilityFocusedUIElement
{
    if (!m_object)
        return nil;

    m_object->updateBackingStore();

    RefPtr<AccessibilityObject> focusedObj = m_object->focusedUIElement();

    if (!focusedObj)
        return nil;
    
    return focusedObj->wrapper();
}

- (id)accessibilityHitTest:(NSPoint)point
{
    if (!m_object)
        return nil;

    m_object->updateBackingStore();

    RefPtr<AccessibilityObject> axObject = m_object->doAccessibilityHitTest(IntPoint(point));
    if (axObject)
        return NSAccessibilityUnignoredAncestor(axObject->wrapper());
    return NSAccessibilityUnignoredAncestor(self);
}

- (BOOL)accessibilityIsAttributeSettable:(NSString*)attributeName
{
    if (!m_object)
        return nil;

    m_object->updateBackingStore();

    if ([attributeName isEqualToString: @"AXSelectedTextMarkerRange"])
        return YES;

    if ([attributeName isEqualToString: NSAccessibilityFocusedAttribute])
        return m_object->canSetFocusAttribute();

    if ([attributeName isEqualToString: NSAccessibilityValueAttribute])
        return m_object->canSetValueAttribute();

    if ([attributeName isEqualToString: NSAccessibilitySelectedAttribute])
        return m_object->canSetSelectedAttribute();
    
    if ([attributeName isEqualToString: NSAccessibilitySelectedChildrenAttribute])
        return m_object->canSetSelectedChildrenAttribute();

    if ([attributeName isEqualToString: NSAccessibilitySelectedTextAttribute] ||
        [attributeName isEqualToString: NSAccessibilitySelectedTextRangeAttribute] ||
        [attributeName isEqualToString: NSAccessibilityVisibleCharacterRangeAttribute])
        return m_object->canSetTextRangeAttributes();
    
    return NO;
}

// accessibilityShouldUseUniqueId is an AppKit method we override so that
// objects will be given a unique ID, and therefore allow AppKit to know when they
// become obsolete (e.g. when the user navigates to a new web page, making this one
// unrendered but not deallocated because it is in the back/forward cache).
// It is important to call NSAccessibilityUnregisterUniqueIdForUIElement in the
// appropriate place (e.g. dealloc) to remove these non-retained references from
// AppKit's id mapping tables. We do this in detach by calling unregisterUniqueIdForUIElement.
//
// Registering an object is also required for observing notifications. Only registered objects can be observed.
- (BOOL)accessibilityIsIgnored
{
    if (!m_object)
        return nil;

    m_object->updateBackingStore();

    if (m_object->isAttachment())
        return [[self attachmentView] accessibilityIsIgnored];
    return m_object->accessibilityIsIgnored();
}

- (NSArray* )accessibilityParameterizedAttributeNames
{
    if (!m_object)
        return nil;

    m_object->updateBackingStore();

    if (m_object->isAttachment()) 
        return nil;

    static NSArray* paramAttrs = nil;
    static NSArray* textParamAttrs = nil;
    static NSArray* tableParamAttrs = nil;
    if (paramAttrs == nil) {
        paramAttrs = [[NSArray alloc] initWithObjects:
                      @"AXUIElementForTextMarker",
                      @"AXTextMarkerRangeForUIElement",
                      @"AXLineForTextMarker",
                      @"AXTextMarkerRangeForLine",
                      @"AXStringForTextMarkerRange",
                      @"AXTextMarkerForPosition",
                      @"AXBoundsForTextMarkerRange",
                      @"AXAttributedStringForTextMarkerRange",
                      @"AXTextMarkerRangeForUnorderedTextMarkers",
                      @"AXNextTextMarkerForTextMarker",
                      @"AXPreviousTextMarkerForTextMarker",
                      @"AXLeftWordTextMarkerRangeForTextMarker",
                      @"AXRightWordTextMarkerRangeForTextMarker",
                      @"AXLeftLineTextMarkerRangeForTextMarker",
                      @"AXRightLineTextMarkerRangeForTextMarker",
                      @"AXSentenceTextMarkerRangeForTextMarker",
                      @"AXParagraphTextMarkerRangeForTextMarker",
                      @"AXNextWordEndTextMarkerForTextMarker",
                      @"AXPreviousWordStartTextMarkerForTextMarker",
                      @"AXNextLineEndTextMarkerForTextMarker",
                      @"AXPreviousLineStartTextMarkerForTextMarker",
                      @"AXNextSentenceEndTextMarkerForTextMarker",
                      @"AXPreviousSentenceStartTextMarkerForTextMarker",
                      @"AXNextParagraphEndTextMarkerForTextMarker",
                      @"AXPreviousParagraphStartTextMarkerForTextMarker",
                      @"AXStyleTextMarkerRangeForTextMarker",
                      @"AXLengthForTextMarkerRange",
                      NSAccessibilityBoundsForRangeParameterizedAttribute,
                      nil];
    }

    if (textParamAttrs == nil) {
        NSMutableArray* tempArray = [[NSMutableArray alloc] initWithArray:paramAttrs]