1/*
2 * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
3 * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
4 *
5 * Portions are Copyright (C) 1998 Netscape Communications Corporation.
6 *
7 * Other contributors:
8 *   Robert O'Callahan <roc+@cs.cmu.edu>
9 *   David Baron <dbaron@fas.harvard.edu>
10 *   Christian Biesinger <cbiesinger@web.de>
11 *   Randall Jesup <rjesup@wgate.com>
12 *   Roland Mainz <roland.mainz@informatik.med.uni-giessen.de>
13 *   Josh Soref <timeless@mac.com>
14 *   Boris Zbarsky <bzbarsky@mit.edu>
15 *
16 * This library is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU Lesser General Public
18 * License as published by the Free Software Foundation; either
19 * version 2.1 of the License, or (at your option) any later version.
20 *
21 * This library is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
24 * Lesser General Public License for more details.
25 *
26 * You should have received a copy of the GNU Lesser General Public
27 * License along with this library; if not, write to the Free Software
28 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
29 *
30 * Alternatively, the contents of this file may be used under the terms
31 * of either the Mozilla Public License Version 1.1, found at
32 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
33 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
34 * (the "GPL"), in which case the provisions of the MPL or the GPL are
35 * applicable instead of those above.  If you wish to allow use of your
36 * version of this file only under the terms of one of those two
37 * licenses (the MPL or the GPL) and not to allow others to use your
38 * version of this file under the LGPL, indicate your decision by
39 * deletingthe provisions above and replace them with the notice and
40 * other provisions required by the MPL or the GPL, as the case may be.
41 * If you do not delete the provisions above, a recipient may use your
42 * version of this file under any of the LGPL, the MPL or the GPL.
43 */
44
45#include "config.h"
46
47#include "core/rendering/RenderMarquee.h"
48
49#include "core/HTMLNames.h"
50#include "core/html/HTMLMarqueeElement.h"
51#include "core/frame/FrameView.h"
52#include "core/frame/UseCounter.h"
53#include "core/rendering/RenderLayer.h"
54#include "core/rendering/RenderView.h"
55#include "platform/LengthFunctions.h"
56
57namespace blink {
58
59using namespace HTMLNames;
60
61RenderMarquee::RenderMarquee(HTMLMarqueeElement* element)
62    : RenderBlockFlow(element)
63    , m_currentLoop(0)
64    , m_totalLoops(0)
65    , m_timer(element, &HTMLMarqueeElement::timerFired)
66    , m_start(0)
67    , m_end(0)
68    , m_speed(0)
69    , m_reset(false)
70    , m_suspended(false)
71    , m_stopped(false)
72    , m_direction(MAUTO)
73{
74    UseCounter::count(document(), UseCounter::HTMLMarqueeElement);
75}
76
77RenderMarquee::~RenderMarquee()
78{
79}
80
81int RenderMarquee::marqueeSpeed() const
82{
83    int result = style()->marqueeSpeed();
84    if (Node* node = this->node())
85        result = std::max(result, toHTMLMarqueeElement(node)->minimumDelay());
86    return result;
87}
88
89EMarqueeDirection RenderMarquee::direction() const
90{
91    // FIXME: Support the CSS3 "auto" value for determining the direction of the marquee.
92    // For now just map MAUTO to MBACKWARD
93    EMarqueeDirection result = style()->marqueeDirection();
94    TextDirection dir = style()->direction();
95    if (result == MAUTO)
96        result = MBACKWARD;
97    if (result == MFORWARD)
98        result = (dir == LTR) ? MRIGHT : MLEFT;
99    if (result == MBACKWARD)
100        result = (dir == LTR) ? MLEFT : MRIGHT;
101
102    // Now we have the real direction.  Next we check to see if the increment is negative.
103    // If so, then we reverse the direction.
104    Length increment = style()->marqueeIncrement();
105    if (increment.isNegative())
106        result = static_cast<EMarqueeDirection>(-result);
107
108    return result;
109}
110
111bool RenderMarquee::isHorizontal() const
112{
113    return direction() == MLEFT || direction() == MRIGHT;
114}
115
116int RenderMarquee::computePosition(EMarqueeDirection dir, bool stopAtContentEdge)
117{
118    if (isHorizontal()) {
119        bool ltr = style()->isLeftToRightDirection();
120        LayoutUnit clientWidth = this->clientWidth();
121        LayoutUnit contentWidth = ltr ? maxPreferredLogicalWidth() : minPreferredLogicalWidth();
122        if (ltr)
123            contentWidth += (paddingRight() - borderLeft());
124        else {
125            contentWidth = width() - contentWidth;
126            contentWidth += (paddingLeft() - borderRight());
127        }
128        if (dir == MRIGHT) {
129            if (stopAtContentEdge)
130                return std::max<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
131            else
132                return ltr ? contentWidth : clientWidth;
133        }
134        else {
135            if (stopAtContentEdge)
136                return std::min<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
137            else
138                return ltr ? -clientWidth : -contentWidth;
139        }
140    }
141    else {
142        int contentHeight = layoutOverflowRect().maxY() - borderTop() + paddingBottom();
143        int clientHeight = this->clientHeight();
144        if (dir == MUP) {
145            if (stopAtContentEdge)
146                return std::min(contentHeight - clientHeight, 0);
147            else
148                return -clientHeight;
149        }
150        else {
151            if (stopAtContentEdge)
152                return std::max(contentHeight - clientHeight, 0);
153            else
154                return contentHeight;
155        }
156    }
157}
158
159void RenderMarquee::start()
160{
161    if (m_timer.isActive() || style()->marqueeIncrement().isZero())
162        return;
163
164    if (!m_suspended && !m_stopped) {
165        if (isHorizontal())
166            layer()->scrollableArea()->scrollToOffset(IntSize(m_start, 0));
167        else
168            layer()->scrollableArea()->scrollToOffset(IntSize(0, m_start));
169    } else {
170        m_suspended = false;
171        m_stopped = false;
172    }
173
174    m_timer.startRepeating(speed() * 0.001, FROM_HERE);
175}
176
177void RenderMarquee::suspend()
178{
179    m_timer.stop();
180    m_suspended = true;
181}
182
183void RenderMarquee::stop()
184{
185    m_timer.stop();
186    m_stopped = true;
187}
188
189void RenderMarquee::updateMarqueePosition()
190{
191    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
192    if (activate) {
193        EMarqueeBehavior behavior = style()->marqueeBehavior();
194        m_start = computePosition(direction(), behavior == MALTERNATE);
195        m_end = computePosition(reverseDirection(), behavior == MALTERNATE || behavior == MSLIDE);
196        if (!m_stopped) {
197            // Hits in compositing/overflow/do-not-repaint-if-scrolling-composited-layers.html during layout.
198            DisableCompositingQueryAsserts disabler;
199            start();
200        }
201    }
202}
203
204const char* RenderMarquee::renderName() const
205{
206    if (isFloating())
207        return "RenderMarquee (floating)";
208    if (isOutOfFlowPositioned())
209        return "RenderMarquee (positioned)";
210    if (isAnonymous())
211        return "RenderMarquee (generated)";
212    if (isRelPositioned())
213        return "RenderMarquee (relative positioned)";
214    return "RenderMarquee";
215
216}
217
218void RenderMarquee::styleDidChange(StyleDifference difference, const RenderStyle* oldStyle)
219{
220    RenderBlockFlow::styleDidChange(difference, oldStyle);
221
222    RenderStyle* s = style();
223
224    if (m_direction != s->marqueeDirection() || (m_totalLoops != s->marqueeLoopCount() && m_currentLoop >= m_totalLoops))
225        m_currentLoop = 0; // When direction changes or our loopCount is a smaller number than our current loop, reset our loop.
226
227    m_totalLoops = s->marqueeLoopCount();
228    m_direction = s->marqueeDirection();
229
230    // Hack for WinIE. In WinIE, a value of 0 or lower for the loop count for SLIDE means to only do
231    // one loop.
232    if (m_totalLoops <= 0 && s->marqueeBehavior() == MSLIDE)
233        m_totalLoops = 1;
234
235    // Hack alert: Set the white-space value to nowrap for horizontal marquees with inline children, thus ensuring
236    // all the text ends up on one line by default. Limit this hack to the <marquee> element to emulate
237    // WinIE's behavior. Someone using CSS3 can use white-space: nowrap on their own to get this effect.
238    // Second hack alert: Set the text-align back to auto. WinIE completely ignores text-align on the
239    // marquee element.
240    // FIXME: Bring these up with the CSS WG.
241    if (isHorizontal() && childrenInline()) {
242        s->setWhiteSpace(NOWRAP);
243        s->setTextAlign(TASTART);
244    }
245
246    // Legacy hack - multiple browsers default vertical marquees to 200px tall.
247    if (!isHorizontal() && s->height().isAuto())
248        s->setHeight(Length(200, Fixed));
249
250    if (speed() != marqueeSpeed()) {
251        m_speed = marqueeSpeed();
252        if (m_timer.isActive())
253            m_timer.startRepeating(speed() * 0.001, FROM_HERE);
254    }
255
256    // Check the loop count to see if we should now stop.
257    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
258    if (activate && !m_timer.isActive())
259        setNeedsLayoutAndFullPaintInvalidation();
260    else if (!activate && m_timer.isActive())
261        m_timer.stop();
262}
263
264void RenderMarquee::layoutBlock(bool relayoutChildren)
265{
266    RenderBlockFlow::layoutBlock(relayoutChildren);
267
268    updateMarqueePosition();
269}
270
271void RenderMarquee::timerFired()
272{
273    // FIXME: Why do we need to check the view and not just the RenderMarquee itself?
274    if (view()->needsLayout())
275        return;
276
277    if (m_reset) {
278        m_reset = false;
279        if (isHorizontal())
280            layer()->scrollableArea()->scrollToXOffset(m_start);
281        else
282            layer()->scrollableArea()->scrollToYOffset(m_start);
283        return;
284    }
285
286    RenderStyle* s = style();
287
288    int endPoint = m_end;
289    int range = m_end - m_start;
290    int newPos;
291    if (range == 0)
292        newPos = m_end;
293    else {
294        bool addIncrement = direction() == MUP || direction() == MLEFT;
295        bool isReversed = s->marqueeBehavior() == MALTERNATE && m_currentLoop % 2;
296        if (isReversed) {
297            // We're going in the reverse direction.
298            endPoint = m_start;
299            range = -range;
300            addIncrement = !addIncrement;
301        }
302        bool positive = range > 0;
303        int clientSize = (isHorizontal() ? clientWidth() : clientHeight());
304        int increment = abs(intValueForLength(style()->marqueeIncrement(), clientSize));
305        int currentPos = (isHorizontal() ? layer()->scrollableArea()->scrollXOffset() : layer()->scrollableArea()->scrollYOffset());
306        newPos =  currentPos + (addIncrement ? increment : -increment);
307        if (positive)
308            newPos = std::min(newPos, endPoint);
309        else
310            newPos = std::max(newPos, endPoint);
311    }
312
313    if (newPos == endPoint) {
314        m_currentLoop++;
315        if (m_totalLoops > 0 && m_currentLoop >= m_totalLoops)
316            m_timer.stop();
317        else if (s->marqueeBehavior() != MALTERNATE)
318            m_reset = true;
319    }
320
321    if (isHorizontal())
322        layer()->scrollableArea()->scrollToXOffset(newPos);
323    else
324        layer()->scrollableArea()->scrollToYOffset(newPos);
325}
326
327} // namespace blink
328