1/*
2 * Copyright (C) 2011 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 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "AccessibilityScrollView.h"
28
29#include "AXObjectCache.h"
30#include "AccessibilityScrollbar.h"
31#include "Frame.h"
32#include "FrameView.h"
33#include "HTMLFrameOwnerElement.h"
34#include "RenderElement.h"
35#include "ScrollView.h"
36#include "Widget.h"
37
38namespace WebCore {
39
40AccessibilityScrollView::AccessibilityScrollView(ScrollView* view)
41    : m_scrollView(view)
42    , m_childrenDirty(false)
43{
44}
45
46AccessibilityScrollView::~AccessibilityScrollView()
47{
48    ASSERT(isDetached());
49}
50
51void AccessibilityScrollView::detach(AccessibilityDetachmentType detachmentType, AXObjectCache* cache)
52{
53    AccessibilityObject::detach(detachmentType, cache);
54    m_scrollView = 0;
55}
56
57PassRefPtr<AccessibilityScrollView> AccessibilityScrollView::create(ScrollView* view)
58{
59    return adoptRef(new AccessibilityScrollView(view));
60}
61
62AccessibilityObject* AccessibilityScrollView::scrollBar(AccessibilityOrientation orientation)
63{
64    updateScrollbars();
65
66    switch (orientation) {
67    case AccessibilityOrientationVertical:
68        return m_verticalScrollbar ? m_verticalScrollbar.get() : 0;
69    case AccessibilityOrientationHorizontal:
70        return m_horizontalScrollbar ? m_horizontalScrollbar.get() : 0;
71    }
72
73    return 0;
74}
75
76// If this is WebKit1 then the native scroll view needs to return the
77// AX information (because there are no scroll bar children in the ScrollView object in WK1).
78// In WebKit2, the ScrollView object will return the AX information (because there are no platform widgets).
79bool AccessibilityScrollView::isAttachment() const
80{
81    return m_scrollView && m_scrollView->platformWidget();
82}
83
84Widget* AccessibilityScrollView::widgetForAttachmentView() const
85{
86    return m_scrollView;
87}
88
89bool AccessibilityScrollView::canSetFocusAttribute() const
90{
91    AccessibilityObject* webArea = webAreaObject();
92    return webArea && webArea->canSetFocusAttribute();
93}
94
95bool AccessibilityScrollView::isFocused() const
96{
97    AccessibilityObject* webArea = webAreaObject();
98    return webArea && webArea->isFocused();
99}
100
101void AccessibilityScrollView::setFocused(bool focused)
102{
103    if (AccessibilityObject* webArea = webAreaObject())
104        webArea->setFocused(focused);
105}
106
107void AccessibilityScrollView::updateChildrenIfNecessary()
108{
109    if (m_childrenDirty)
110        clearChildren();
111
112    if (!m_haveChildren)
113        addChildren();
114
115    updateScrollbars();
116}
117
118void AccessibilityScrollView::updateScrollbars()
119{
120    if (!m_scrollView)
121        return;
122
123    if (m_scrollView->horizontalScrollbar() && !m_horizontalScrollbar)
124        m_horizontalScrollbar = addChildScrollbar(m_scrollView->horizontalScrollbar());
125    else if (!m_scrollView->horizontalScrollbar() && m_horizontalScrollbar) {
126        removeChildScrollbar(m_horizontalScrollbar.get());
127        m_horizontalScrollbar = 0;
128    }
129
130    if (m_scrollView->verticalScrollbar() && !m_verticalScrollbar)
131        m_verticalScrollbar = addChildScrollbar(m_scrollView->verticalScrollbar());
132    else if (!m_scrollView->verticalScrollbar() && m_verticalScrollbar) {
133        removeChildScrollbar(m_verticalScrollbar.get());
134        m_verticalScrollbar = 0;
135    }
136}
137
138void AccessibilityScrollView::removeChildScrollbar(AccessibilityObject* scrollbar)
139{
140    size_t pos = m_children.find(scrollbar);
141    if (pos != WTF::notFound) {
142        m_children[pos]->detachFromParent();
143        m_children.remove(pos);
144    }
145}
146
147AccessibilityScrollbar* AccessibilityScrollView::addChildScrollbar(Scrollbar* scrollbar)
148{
149    if (!scrollbar)
150        return 0;
151
152    AXObjectCache* cache = axObjectCache();
153    if (!cache)
154        return nullptr;
155
156    AccessibilityScrollbar* scrollBarObject = toAccessibilityScrollbar(cache->getOrCreate(scrollbar));
157    scrollBarObject->setParent(this);
158    m_children.append(scrollBarObject);
159    return scrollBarObject;
160}
161
162void AccessibilityScrollView::clearChildren()
163{
164    AccessibilityObject::clearChildren();
165    m_verticalScrollbar = 0;
166    m_horizontalScrollbar = 0;
167}
168
169bool AccessibilityScrollView::computeAccessibilityIsIgnored() const
170{
171    AccessibilityObject* webArea = webAreaObject();
172    if (!webArea)
173        return true;
174
175    return webArea->accessibilityIsIgnored();
176}
177
178void AccessibilityScrollView::addChildren()
179{
180    ASSERT(!m_haveChildren);
181    m_haveChildren = true;
182
183    AccessibilityObject* webArea = webAreaObject();
184    if (webArea && !webArea->accessibilityIsIgnored())
185        m_children.append(webArea);
186
187    updateScrollbars();
188}
189
190AccessibilityObject* AccessibilityScrollView::webAreaObject() const
191{
192    if (!m_scrollView || !m_scrollView->isFrameView())
193        return 0;
194
195    Document* doc = toFrameView(m_scrollView)->frame().document();
196    if (!doc || !doc->hasLivingRenderTree())
197        return 0;
198
199    if (AXObjectCache* cache = axObjectCache())
200        return cache->getOrCreate(doc);
201
202    return nullptr;
203}
204
205AccessibilityObject* AccessibilityScrollView::accessibilityHitTest(const IntPoint& point) const
206{
207    AccessibilityObject* webArea = webAreaObject();
208    if (!webArea)
209        return 0;
210
211    if (m_horizontalScrollbar && m_horizontalScrollbar->elementRect().contains(point))
212        return m_horizontalScrollbar.get();
213    if (m_verticalScrollbar && m_verticalScrollbar->elementRect().contains(point))
214        return m_verticalScrollbar.get();
215
216    return webArea->accessibilityHitTest(point);
217}
218
219LayoutRect AccessibilityScrollView::elementRect() const
220{
221    if (!m_scrollView)
222        return LayoutRect();
223
224    LayoutRect rect = m_scrollView->frameRect();
225    rect.setY(rect.y() + m_scrollView->topContentInset());
226    return rect;
227}
228
229FrameView* AccessibilityScrollView::documentFrameView() const
230{
231    if (!m_scrollView || !m_scrollView->isFrameView())
232        return 0;
233
234    return toFrameView(m_scrollView);
235}
236
237AccessibilityObject* AccessibilityScrollView::parentObject() const
238{
239    if (!m_scrollView || !m_scrollView->isFrameView())
240        return 0;
241
242    AXObjectCache* cache = axObjectCache();
243    if (!cache)
244        return nullptr;
245
246    HTMLFrameOwnerElement* owner = toFrameView(m_scrollView)->frame().ownerElement();
247    if (owner && owner->renderer())
248        return cache->getOrCreate(owner);
249
250    return 0;
251}
252
253AccessibilityObject* AccessibilityScrollView::parentObjectIfExists() const
254{
255    if (!m_scrollView || !m_scrollView->isFrameView())
256        return 0;
257
258    AXObjectCache* cache = axObjectCache();
259    if (!cache)
260        return nullptr;
261
262    HTMLFrameOwnerElement* owner = toFrameView(m_scrollView)->frame().ownerElement();
263    if (owner && owner->renderer())
264        return cache->get(owner);
265
266    return 0;
267}
268
269ScrollableArea* AccessibilityScrollView::getScrollableAreaIfScrollable() const
270{
271    return m_scrollView;
272}
273
274void AccessibilityScrollView::scrollTo(const IntPoint& point) const
275{
276    if (m_scrollView)
277        m_scrollView->setScrollPosition(point);
278}
279
280} // namespace WebCore
281