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 "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
56using namespace std;
57
58namespace WebCore {
59
60using namespace HTMLNames;
61
62RenderMarquee::RenderMarquee(HTMLMarqueeElement* element)
63    : RenderBlockFlow(element)
64    , m_currentLoop(0)
65    , m_totalLoops(0)
66    , m_timer(element, &HTMLMarqueeElement::timerFired)
67    , m_start(0)
68    , m_end(0)
69    , m_speed(0)
70    , m_reset(false)
71    , m_suspended(false)
72    , m_stopped(false)
73    , m_direction(MAUTO)
74{
75    UseCounter::count(document(), UseCounter::HTMLMarqueeElement);
76}
77
78RenderMarquee::~RenderMarquee()
79{
80}
81
82int RenderMarquee::marqueeSpeed() const
83{
84    int result = style()->marqueeSpeed();
85    if (Node* node = this->node())
86        result = std::max(result, toHTMLMarqueeElement(node)->minimumDelay());
87    return result;
88}
89
90EMarqueeDirection RenderMarquee::direction() const
91{
92    // FIXME: Support the CSS3 "auto" value for determining the direction of the marquee.
93    // For now just map MAUTO to MBACKWARD
94    EMarqueeDirection result = style()->marqueeDirection();
95    TextDirection dir = style()->direction();
96    if (result == MAUTO)
97        result = MBACKWARD;
98    if (result == MFORWARD)
99        result = (dir == LTR) ? MRIGHT : MLEFT;
100    if (result == MBACKWARD)
101        result = (dir == LTR) ? MLEFT : MRIGHT;
102
103    // Now we have the real direction.  Next we check to see if the increment is negative.
104    // If so, then we reverse the direction.
105    Length increment = style()->marqueeIncrement();
106    if (increment.isNegative())
107        result = static_cast<EMarqueeDirection>(-result);
108
109    return result;
110}
111
112bool RenderMarquee::isHorizontal() const
113{
114    return direction() == MLEFT || direction() == MRIGHT;
115}
116
117int RenderMarquee::computePosition(EMarqueeDirection dir, bool stopAtContentEdge)
118{
119    if (isHorizontal()) {
120        bool ltr = style()->isLeftToRightDirection();
121        LayoutUnit clientWidth = this->clientWidth();
122        LayoutUnit contentWidth = ltr ? maxPreferredLogicalWidth() : minPreferredLogicalWidth();
123        if (ltr)
124            contentWidth += (paddingRight() - borderLeft());
125        else {
126            contentWidth = width() - contentWidth;
127            contentWidth += (paddingLeft() - borderRight());
128        }
129        if (dir == MRIGHT) {
130            if (stopAtContentEdge)
131                return max<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
132            else
133                return ltr ? contentWidth : clientWidth;
134        }
135        else {
136            if (stopAtContentEdge)
137                return min<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
138            else
139                return ltr ? -clientWidth : -contentWidth;
140        }
141    }
142    else {
143        int contentHeight = layoutOverflowRect().maxY() - borderTop() + paddingBottom();
144        int clientHeight = this->clientHeight();
145        if (dir == MUP) {
146            if (stopAtContentEdge)
147                 return min(contentHeight - clientHeight, 0);
148            else
149                return -clientHeight;
150        }
151        else {
152            if (stopAtContentEdge)
153                return max(contentHeight - clientHeight, 0);
154            else
155                return contentHeight;
156        }
157    }
158}
159
160void RenderMarquee::start()
161{
162    if (m_timer.isActive() || style()->marqueeIncrement().isZero())
163        return;
164
165    if (!m_suspended && !m_stopped) {
166        if (isHorizontal())
167            layer()->scrollableArea()->scrollToOffset(IntSize(m_start, 0));
168        else
169            layer()->scrollableArea()->scrollToOffset(IntSize(0, m_start));
170    } else {
171        m_suspended = false;
172        m_stopped = false;
173    }
174
175    m_timer.startRepeating(speed() * 0.001);
176}
177
178void RenderMarquee::suspend()
179{
180    m_timer.stop();
181    m_suspended = true;
182}
183
184void RenderMarquee::stop()
185{
186    m_timer.stop();
187    m_stopped = true;
188}
189
190void RenderMarquee::updateMarqueePosition()
191{
192    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
193    if (activate) {
194        EMarqueeBehavior behavior = style()->marqueeBehavior();
195        m_start = computePosition(direction(), behavior == MALTERNATE);
196        m_end = computePosition(reverseDirection(), behavior == MALTERNATE || behavior == MSLIDE);
197        if (!m_stopped)
198            start();
199    }
200}
201
202const char* RenderMarquee::renderName() const
203{
204    if (isFloating())
205        return "RenderMarquee (floating)";
206    if (isOutOfFlowPositioned())
207        return "RenderMarquee (positioned)";
208    if (isAnonymous())
209        return "RenderMarquee (generated)";
210    if (isRelPositioned())
211        return "RenderMarquee (relative positioned)";
212    return "RenderMarquee";
213
214}
215
216void RenderMarquee::styleDidChange(StyleDifference difference, const RenderStyle* oldStyle)
217{
218    RenderBlock::styleDidChange(difference, oldStyle);
219
220    RenderStyle* s = style();
221
222    if (m_direction != s->marqueeDirection() || (m_totalLoops != s->marqueeLoopCount() && m_currentLoop >= m_totalLoops))
223        m_currentLoop = 0; // When direction changes or our loopCount is a smaller number than our current loop, reset our loop.
224
225    m_totalLoops = s->marqueeLoopCount();
226    m_direction = s->marqueeDirection();
227
228    // Hack for WinIE. In WinIE, a value of 0 or lower for the loop count for SLIDE means to only do
229    // one loop.
230    if (m_totalLoops <= 0 && s->marqueeBehavior() == MSLIDE)
231        m_totalLoops = 1;
232
233    // Hack alert: Set the white-space value to nowrap for horizontal marquees with inline children, thus ensuring
234    // all the text ends up on one line by default. Limit this hack to the <marquee> element to emulate
235    // WinIE's behavior. Someone using CSS3 can use white-space: nowrap on their own to get this effect.
236    // Second hack alert: Set the text-align back to auto. WinIE completely ignores text-align on the
237    // marquee element.
238    // FIXME: Bring these up with the CSS WG.
239    if (isHorizontal() && childrenInline()) {
240        s->setWhiteSpace(NOWRAP);
241        s->setTextAlign(TASTART);
242    }
243
244    // Legacy hack - multiple browsers default vertical marquees to 200px tall.
245    if (!isHorizontal() && s->height().isAuto())
246        s->setHeight(Length(200, Fixed));
247
248    if (speed() != marqueeSpeed()) {
249        m_speed = marqueeSpeed();
250        if (m_timer.isActive())
251            m_timer.startRepeating(speed() * 0.001);
252    }
253
254    // Check the loop count to see if we should now stop.
255    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
256    if (activate && !m_timer.isActive())
257        setNeedsLayout();
258    else if (!activate && m_timer.isActive())
259        m_timer.stop();
260}
261
262void RenderMarquee::layoutBlock(bool relayoutChildren, LayoutUnit pageLogicalHeight)
263{
264    RenderBlockFlow::layoutBlock(relayoutChildren, pageLogicalHeight);
265
266    updateMarqueePosition();
267}
268
269void RenderMarquee::timerFired()
270{
271    // FIXME: Why do we need to check the view and not just the RenderMarquee itself?
272    if (view()->needsLayout())
273        return;
274
275    if (m_reset) {
276        m_reset = false;
277        if (isHorizontal())
278            layer()->scrollableArea()->scrollToXOffset(m_start);
279        else
280            layer()->scrollableArea()->scrollToYOffset(m_start);
281        return;
282    }
283
284    RenderStyle* s = style();
285
286    int endPoint = m_end;
287    int range = m_end - m_start;
288    int newPos;
289    if (range == 0)
290        newPos = m_end;
291    else {
292        bool addIncrement = direction() == MUP || direction() == MLEFT;
293        bool isReversed = s->marqueeBehavior() == MALTERNATE && m_currentLoop % 2;
294        if (isReversed) {
295            // We're going in the reverse direction.
296            endPoint = m_start;
297            range = -range;
298            addIncrement = !addIncrement;
299        }
300        bool positive = range > 0;
301        int clientSize = (isHorizontal() ? clientWidth() : clientHeight());
302        int increment = abs(intValueForLength(style()->marqueeIncrement(), clientSize));
303        int currentPos = (isHorizontal() ? layer()->scrollableArea()->scrollXOffset() : layer()->scrollableArea()->scrollYOffset());
304        newPos =  currentPos + (addIncrement ? increment : -increment);
305        if (positive)
306            newPos = min(newPos, endPoint);
307        else
308            newPos = max(newPos, endPoint);
309    }
310
311    if (newPos == endPoint) {
312        m_currentLoop++;
313        if (m_totalLoops > 0 && m_currentLoop >= m_totalLoops)
314            m_timer.stop();
315        else if (s->marqueeBehavior() != MALTERNATE)
316            m_reset = true;
317    }
318
319    if (isHorizontal())
320        layer()->scrollableArea()->scrollToXOffset(newPos);
321    else
322        layer()->scrollableArea()->scrollToYOffset(newPos);
323}
324
325} // namespace WebCore
326