1/*
2 * Copyright (C) 2008 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef AccessibilityRenderObject_h
30#define AccessibilityRenderObject_h
31
32#include "core/accessibility/AccessibilityNodeObject.h"
33#include "core/platform/graphics/LayoutRect.h"
34#include "wtf/Forward.h"
35
36namespace WebCore {
37
38class AccessibilitySVGRoot;
39class AXObjectCache;
40class Element;
41class Frame;
42class FrameView;
43class HitTestResult;
44class HTMLAnchorElement;
45class HTMLAreaElement;
46class HTMLElement;
47class HTMLLabelElement;
48class HTMLMapElement;
49class HTMLSelectElement;
50class IntPoint;
51class IntSize;
52class Node;
53class RenderListBox;
54class RenderTextControl;
55class RenderView;
56class VisibleSelection;
57class Widget;
58
59class AccessibilityRenderObject : public AccessibilityNodeObject {
60protected:
61    explicit AccessibilityRenderObject(RenderObject*);
62public:
63    static PassRefPtr<AccessibilityRenderObject> create(RenderObject*);
64    virtual ~AccessibilityRenderObject();
65
66    // Public, overridden from AccessibilityObject.
67    virtual RenderObject* renderer() const OVERRIDE { return m_renderer; }
68    virtual LayoutRect elementRect() const OVERRIDE;
69
70    void setRenderer(RenderObject*);
71    RenderBoxModelObject* renderBoxModelObject() const;
72    RenderView* topRenderer() const;
73    Document* topDocument() const;
74    HTMLLabelElement* labelElementContainer() const;
75    bool shouldNotifyActiveDescendant() const;
76    bool needsToUpdateChildren() const { return m_childrenDirty; }
77    ScrollableArea* getScrollableAreaIfScrollable() const;
78    virtual AccessibilityRole determineAccessibilityRole() OVERRIDE;
79    void checkCachedElementRect() const;
80    void updateCachedElementRect() const;
81
82protected:
83    RenderObject* m_renderer;
84    mutable LayoutRect m_cachedElementRect;
85    mutable LayoutRect m_cachedFrameRect;
86    mutable IntPoint m_cachedScrollPosition;
87    mutable bool m_cachedElementRectDirty;
88
89    //
90    // Overridden from AccessibilityObject.
91    //
92
93    virtual void init() OVERRIDE;
94    virtual void detach() OVERRIDE;
95    virtual bool isDetached() const OVERRIDE { return !m_renderer; }
96    virtual bool isAccessibilityRenderObject() const OVERRIDE { return true; }
97
98    // Check object role or purpose.
99    virtual bool isAttachment() const OVERRIDE;
100    virtual bool isFileUploadButton() const OVERRIDE;
101    virtual bool isLinked() const OVERRIDE;
102    virtual bool isLoaded() const OVERRIDE;
103    virtual bool isOffScreen() const OVERRIDE;
104    virtual bool isReadOnly() const OVERRIDE;
105    virtual bool isVisited() const OVERRIDE;
106
107    // Check object state.
108    virtual bool isFocused() const OVERRIDE;
109    virtual bool isSelected() const OVERRIDE;
110
111    // Check whether certain properties can be modified.
112    virtual bool canSetValueAttribute() const OVERRIDE;
113
114    // Whether objects are ignored, i.e. not included in the tree.
115    virtual AccessibilityObjectInclusion defaultObjectInclusion() const OVERRIDE;
116    virtual bool computeAccessibilityIsIgnored() const OVERRIDE;
117
118    // Properties of static elements.
119    virtual const AtomicString& accessKey() const OVERRIDE;
120    virtual bool exposesTitleUIElement() const OVERRIDE;
121    virtual AccessibilityOrientation orientation() const OVERRIDE;
122    virtual String text() const OVERRIDE;
123    virtual int textLength() const OVERRIDE;
124    virtual AccessibilityObject* titleUIElement() const OVERRIDE;
125    virtual KURL url() const OVERRIDE;
126
127    // Properties of interactive elements.
128    virtual String actionVerb() const OVERRIDE;
129    virtual void selectedChildren(AccessibilityChildrenVector&) OVERRIDE;
130    virtual String stringValue() const OVERRIDE;
131
132    // ARIA attributes.
133    virtual AccessibilityObject* activeDescendant() const OVERRIDE;
134    virtual void ariaFlowToElements(AccessibilityChildrenVector&) const OVERRIDE;
135    virtual bool ariaHasPopup() const OVERRIDE;
136    virtual bool ariaRoleHasPresentationalChildren() const OVERRIDE;
137    virtual bool isPresentationalChildOfAriaRole() const OVERRIDE;
138    virtual bool shouldFocusActiveDescendant() const OVERRIDE;
139    virtual bool supportsARIADragging() const OVERRIDE;
140    virtual bool supportsARIADropping() const OVERRIDE;
141    virtual bool supportsARIAFlowTo() const OVERRIDE;
142    virtual bool supportsARIAOwns() const OVERRIDE;
143
144    // ARIA live-region features.
145    virtual const AtomicString& ariaLiveRegionStatus() const OVERRIDE;
146    virtual const AtomicString& ariaLiveRegionRelevant() const OVERRIDE;
147    virtual bool ariaLiveRegionAtomic() const OVERRIDE;
148    virtual bool ariaLiveRegionBusy() const OVERRIDE;
149
150    // Accessibility Text.
151    virtual String textUnderElement() const OVERRIDE;
152
153    // Accessibility Text - (To be deprecated).
154    virtual String helpText() const OVERRIDE;
155
156    // Location and click point in frame-relative coordinates.
157    virtual void markCachedElementRectDirty() const OVERRIDE;
158    virtual IntPoint clickPoint() OVERRIDE;
159
160    // Hit testing.
161    virtual AccessibilityObject* accessibilityHitTest(const IntPoint&) const OVERRIDE;
162    virtual AccessibilityObject* elementAccessibilityHitTest(const IntPoint&) const OVERRIDE;
163
164    // High-level accessibility tree access. Other modules should only use these functions.
165    virtual AccessibilityObject* parentObject() const OVERRIDE;
166    virtual AccessibilityObject* parentObjectIfExists() const OVERRIDE;
167
168    // Low-level accessibility tree exploration, only for use within the accessibility module.
169    virtual AccessibilityObject* firstChild() const OVERRIDE;
170    virtual AccessibilityObject* nextSibling() const OVERRIDE;
171    virtual void addChildren() OVERRIDE;
172    virtual bool canHaveChildren() const OVERRIDE;
173    virtual void updateChildrenIfNecessary() OVERRIDE;
174    virtual void setNeedsToUpdateChildren() OVERRIDE { m_childrenDirty = true; }
175    virtual void clearChildren() OVERRIDE;
176    virtual AccessibilityObject* observableObject() const OVERRIDE;
177
178    // Properties of the object's owning document or page.
179    virtual double estimatedLoadingProgress() const OVERRIDE;
180
181    // DOM and Render tree access.
182    virtual Node* node() const OVERRIDE;
183    virtual Document* document() const OVERRIDE;
184    virtual FrameView* documentFrameView() const OVERRIDE;
185    virtual Element* anchorElement() const OVERRIDE;
186    virtual Widget* widgetForAttachmentView() const OVERRIDE;
187
188    // Selected text.
189    virtual PlainTextRange selectedTextRange() const OVERRIDE;
190    virtual String selectedText() const OVERRIDE;
191
192    // Modify or take an action on an object.
193    virtual void setFocused(bool) OVERRIDE;
194    virtual void setSelectedTextRange(const PlainTextRange&) OVERRIDE;
195    virtual void setValue(const String&) OVERRIDE;
196    virtual void scrollTo(const IntPoint&) const OVERRIDE;
197
198    // Notifications that this object may have changed.
199    virtual void handleActiveDescendantChanged() OVERRIDE;
200    virtual void handleAriaExpandedChanged() OVERRIDE;
201
202    // Text metrics. Most of these should be deprecated, needs major cleanup.
203    virtual int index(const VisiblePosition&) const OVERRIDE;
204    virtual VisiblePosition visiblePositionForIndex(int) const OVERRIDE;
205    virtual void lineBreaks(Vector<int>&) const OVERRIDE;
206
207private:
208    bool isAllowedChildOfTree() const;
209    bool hasTextAlternative() const;
210    void ariaListboxSelectedChildren(AccessibilityChildrenVector&);
211    PlainTextRange ariaSelectedTextRange() const;
212    bool nodeIsTextControl(const Node*) const;
213    bool isTabItemSelected() const;
214    AccessibilityObject* internalLinkElement() const;
215    AccessibilityObject* accessibilityImageMapHitTest(HTMLAreaElement*, const IntPoint&) const;
216    bool renderObjectIsObservable(RenderObject*) const;
217    RenderObject* renderParentObject() const;
218    bool isDescendantOfElementType(const QualifiedName& tagName) const;
219    bool isSVGImage() const;
220    void detachRemoteSVGRoot();
221    AccessibilitySVGRoot* remoteSVGRootElement() const;
222    AccessibilityObject* remoteSVGElementHitTest(const IntPoint&) const;
223    void offsetBoundingBoxForRemoteSVGElement(LayoutRect&) const;
224    void addHiddenChildren();
225    void addTextFieldChildren();
226    void addImageMapChildren();
227    void addCanvasChildren();
228    void addAttachmentChildren();
229    void addRemoteSVGChildren();
230    void ariaSelectedRows(AccessibilityChildrenVector&);
231    bool elementAttributeValue(const QualifiedName&) const;
232    bool inheritsPresentationalRole() const;
233    LayoutRect computeElementRect() const;
234    VisibleSelection selection() const;
235    String stringForRange(const PlainTextRange&) const;
236    AccessibilityObject* correspondingControlForLabelElement() const;
237    int indexForVisiblePosition(const VisiblePosition&) const;
238};
239
240inline AccessibilityRenderObject* toAccessibilityRenderObject(AccessibilityObject* object)
241{
242    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isAccessibilityRenderObject());
243    return static_cast<AccessibilityRenderObject*>(object);
244}
245
246inline const AccessibilityRenderObject* toAccessibilityRenderObject(const AccessibilityObject* object)
247{
248    ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isAccessibilityRenderObject());
249    return static_cast<const AccessibilityRenderObject*>(object);
250}
251
252// This will catch anyone doing an unnecessary cast.
253void toAccessibilityRenderObject(const AccessibilityRenderObject*);
254
255} // namespace WebCore
256
257#endif // AccessibilityRenderObject_h
258