1/*
2 * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
3 * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
4 * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
16 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
23 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include "config.h"
29#include "AutoscrollController.h"
30
31#include "EventHandler.h"
32#include "Frame.h"
33#include "FrameView.h"
34#include "HitTestResult.h"
35#include "Page.h"
36#include "RenderBox.h"
37#include "RenderView.h"
38#include "ScrollView.h"
39#include "Settings.h"
40
41namespace WebCore {
42
43// Delay time in second for start autoscroll if pointer is in border edge of scrollable element.
44static const Seconds autoscrollDelay { 200_ms };
45
46// When the autoscroll or the panScroll is triggered when do the scroll every 50ms to make it smooth.
47static const Seconds autoscrollInterval { 50_ms };
48
49#if ENABLE(PAN_SCROLLING)
50static Frame* getMainFrame(Frame* frame)
51{
52 Page* page = frame->page();
53 return page ? &page->mainFrame() : 0;
54}
55#endif
56
57AutoscrollController::AutoscrollController()
58 : m_autoscrollTimer(*this, &AutoscrollController::autoscrollTimerFired)
59 , m_autoscrollRenderer(nullptr)
60 , m_autoscrollType(NoAutoscroll)
61{
62}
63
64RenderBox* AutoscrollController::autoscrollRenderer() const
65{
66 return m_autoscrollRenderer;
67}
68
69bool AutoscrollController::autoscrollInProgress() const
70{
71 return m_autoscrollType == AutoscrollForSelection;
72}
73
74void AutoscrollController::startAutoscrollForSelection(RenderObject* renderer)
75{
76 // We don't want to trigger the autoscroll or the panScroll if it's already active
77 if (m_autoscrollTimer.isActive())
78 return;
79 RenderBox* scrollable = RenderBox::findAutoscrollable(renderer);
80 if (!scrollable)
81 return;
82 m_autoscrollType = AutoscrollForSelection;
83 m_autoscrollRenderer = scrollable;
84 startAutoscrollTimer();
85}
86
87void AutoscrollController::stopAutoscrollTimer(bool rendererIsBeingDestroyed)
88{
89 RenderBox* scrollable = m_autoscrollRenderer;
90 m_autoscrollTimer.stop();
91 m_autoscrollRenderer = nullptr;
92
93 if (!scrollable)
94 return;
95
96 Frame& frame = scrollable->frame();
97 if (autoscrollInProgress() && frame.eventHandler().mouseDownWasInSubframe()) {
98 if (Frame* subframe = frame.eventHandler().subframeForTargetNode(frame.eventHandler().mousePressNode()))
99 subframe->eventHandler().stopAutoscrollTimer(rendererIsBeingDestroyed);
100 return;
101 }
102
103 if (!rendererIsBeingDestroyed)
104 scrollable->stopAutoscroll();
105#if ENABLE(PAN_SCROLLING)
106 if (panScrollInProgress()) {
107 FrameView& frameView = scrollable->view().frameView();
108 frameView.removePanScrollIcon();
109 frameView.setCursor(pointerCursor());
110 }
111#endif
112
113 m_autoscrollType = NoAutoscroll;
114
115#if ENABLE(PAN_SCROLLING)
116 // If we're not in the top frame we notify it that we are not doing a panScroll any more.
117 if (!frame.isMainFrame())
118 frame.mainFrame().eventHandler().didPanScrollStop();
119#endif
120}
121
122void AutoscrollController::updateAutoscrollRenderer()
123{
124 if (!m_autoscrollRenderer)
125 return;
126
127 RenderObject* renderer = m_autoscrollRenderer;
128
129#if ENABLE(PAN_SCROLLING)
130 HitTestResult hitTest = m_autoscrollRenderer->frame().eventHandler().hitTestResultAtPoint(m_panScrollStartPos, HitTestRequest::ReadOnly | HitTestRequest::Active);
131
132 if (Node* nodeAtPoint = hitTest.innerNode())
133 renderer = nodeAtPoint->renderer();
134#endif
135
136 while (renderer && !(is<RenderBox>(*renderer) && downcast<RenderBox>(*renderer).canAutoscroll()))
137 renderer = renderer->parent();
138 m_autoscrollRenderer = is<RenderBox>(renderer) ? downcast<RenderBox>(renderer) : nullptr;
139}
140
141void AutoscrollController::updateDragAndDrop(Node* dropTargetNode, const IntPoint& eventPosition, WallTime eventTime)
142{
143 if (!dropTargetNode) {
144 stopAutoscrollTimer();
145 return;
146 }
147
148 RenderBox* scrollable = RenderBox::findAutoscrollable(dropTargetNode->renderer());
149 if (!scrollable) {
150 stopAutoscrollTimer();
151 return;
152 }
153
154 Frame& frame = scrollable->frame();
155
156 Page* page = frame.page();
157 if (!page || !page->settings().autoscrollForDragAndDropEnabled()) {
158 stopAutoscrollTimer();
159 return;
160 }
161
162 IntSize offset = scrollable->calculateAutoscrollDirection(eventPosition);
163 if (offset.isZero()) {
164 stopAutoscrollTimer();
165 return;
166 }
167
168 m_dragAndDropAutoscrollReferencePosition = eventPosition + offset;
169
170 if (m_autoscrollType == NoAutoscroll) {
171 m_autoscrollType = AutoscrollForDragAndDrop;
172 m_autoscrollRenderer = scrollable;
173 m_dragAndDropAutoscrollStartTime = eventTime;
174 startAutoscrollTimer();
175 } else if (m_autoscrollRenderer != scrollable) {
176 m_dragAndDropAutoscrollStartTime = eventTime;
177 m_autoscrollRenderer = scrollable;
178 }
179}
180
181#if ENABLE(PAN_SCROLLING)
182void AutoscrollController::didPanScrollStart()
183{
184 m_autoscrollType = AutoscrollForPan;
185}
186
187void AutoscrollController::didPanScrollStop()
188{
189 m_autoscrollType = NoAutoscroll;
190}
191
192void AutoscrollController::handleMouseReleaseEvent(const PlatformMouseEvent& mouseEvent)
193{
194 switch (m_autoscrollType) {
195 case AutoscrollForPan:
196 if (mouseEvent.button() == MiddleButton)
197 m_autoscrollType = AutoscrollForPanCanStop;
198 break;
199 case AutoscrollForPanCanStop:
200 stopAutoscrollTimer();
201 break;
202 default:
203 break;
204 }
205}
206
207bool AutoscrollController::panScrollInProgress() const
208{
209 return m_autoscrollType == AutoscrollForPan || m_autoscrollType == AutoscrollForPanCanStop;
210}
211
212void AutoscrollController::startPanScrolling(RenderBox* scrollable, const IntPoint& lastKnownMousePosition)
213{
214 // We don't want to trigger the autoscroll or the panScroll if it's already active
215 if (m_autoscrollTimer.isActive())
216 return;
217
218 m_autoscrollType = AutoscrollForPan;
219 m_autoscrollRenderer = scrollable;
220 m_panScrollStartPos = lastKnownMousePosition;
221
222 if (FrameView* view = scrollable->frame().view())
223 view->addPanScrollIcon(lastKnownMousePosition);
224 scrollable->frame().eventHandler().didPanScrollStart();
225 startAutoscrollTimer();
226}
227#else
228bool AutoscrollController::panScrollInProgress() const
229{
230 return false;
231}
232#endif
233
234void AutoscrollController::autoscrollTimerFired()
235{
236 if (!m_autoscrollRenderer) {
237 stopAutoscrollTimer();
238 return;
239 }
240
241 Frame& frame = m_autoscrollRenderer->frame();
242 switch (m_autoscrollType) {
243 case AutoscrollForDragAndDrop:
244 if (WallTime::now() - m_dragAndDropAutoscrollStartTime > autoscrollDelay)
245 m_autoscrollRenderer->autoscroll(m_dragAndDropAutoscrollReferencePosition);
246 break;
247 case AutoscrollForSelection: {
248 if (!frame.eventHandler().shouldUpdateAutoscroll()) {
249 stopAutoscrollTimer();
250 return;
251 }
252#if ENABLE(DRAG_SUPPORT)
253 frame.eventHandler().updateSelectionForMouseDrag();
254#endif
255 m_autoscrollRenderer->autoscroll(frame.eventHandler().targetPositionInWindowForSelectionAutoscroll());
256 break;
257 }
258 case NoAutoscroll:
259 break;
260#if ENABLE(PAN_SCROLLING)
261 case AutoscrollForPanCanStop:
262 case AutoscrollForPan:
263 // we verify that the main frame hasn't received the order to stop the panScroll
264 if (Frame* mainFrame = getMainFrame(&frame)) {
265 if (!mainFrame->eventHandler().panScrollInProgress()) {
266 stopAutoscrollTimer();
267 return;
268 }
269 }
270 if (FrameView* view = frame.view())
271 updatePanScrollState(view, frame.eventHandler().lastKnownMousePosition());
272 m_autoscrollRenderer->panScroll(m_panScrollStartPos);
273 break;
274#endif
275 }
276}
277
278void AutoscrollController::startAutoscrollTimer()
279{
280 m_autoscrollTimer.startRepeating(autoscrollInterval);
281}
282
283#if ENABLE(PAN_SCROLLING)
284void AutoscrollController::updatePanScrollState(FrameView* view, const IntPoint& lastKnownMousePosition)
285{
286 // At the original click location we draw a 4 arrowed icon. Over this icon there won't be any scroll
287 // So we don't want to change the cursor over this area
288 bool east = m_panScrollStartPos.x() < (lastKnownMousePosition.x() - ScrollView::noPanScrollRadius);
289 bool west = m_panScrollStartPos.x() > (lastKnownMousePosition.x() + ScrollView::noPanScrollRadius);
290 bool north = m_panScrollStartPos.y() > (lastKnownMousePosition.y() + ScrollView::noPanScrollRadius);
291 bool south = m_panScrollStartPos.y() < (lastKnownMousePosition.y() - ScrollView::noPanScrollRadius);
292
293 if (m_autoscrollType == AutoscrollForPan && (east || west || north || south))
294 m_autoscrollType = AutoscrollForPanCanStop;
295
296 if (north) {
297 if (east)
298 view->setCursor(northEastPanningCursor());
299 else if (west)
300 view->setCursor(northWestPanningCursor());
301 else
302 view->setCursor(northPanningCursor());
303 } else if (south) {
304 if (east)
305 view->setCursor(southEastPanningCursor());
306 else if (west)
307 view->setCursor(southWestPanningCursor());
308 else
309 view->setCursor(southPanningCursor());
310 } else if (east)
311 view->setCursor(eastPanningCursor());
312 else if (west)
313 view->setCursor(westPanningCursor());
314 else
315 view->setCursor(middlePanningCursor());
316}
317#endif
318
319} // namespace WebCore
320