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 "RenderMarquee.h"
48
49#include "FrameView.h"
50#include "HTMLMarqueeElement.h"
51#include "HTMLNames.h"
52#include "RenderLayer.h"
53#include "RenderView.h"
54
55using namespace std;
56
57namespace WebCore {
58
59using namespace HTMLNames;
60
61RenderMarquee::RenderMarquee(RenderLayer* l)
62    : m_layer(l), m_currentLoop(0)
63    , m_totalLoops(0)
64    , m_timer(this, &RenderMarquee::timerFired)
65    , m_start(0), m_end(0), m_speed(0), m_reset(false)
66    , m_suspended(false), m_stopped(false), m_direction(MAUTO)
67{
68}
69
70RenderMarquee::~RenderMarquee()
71{
72}
73
74int RenderMarquee::marqueeSpeed() const
75{
76    int result = m_layer->renderer()->style()->marqueeSpeed();
77    Node* n = m_layer->renderer()->node();
78    if (n && n->hasTagName(marqueeTag)) {
79        HTMLMarqueeElement* marqueeElt = static_cast<HTMLMarqueeElement*>(n);
80        result = max(result, marqueeElt->minimumDelay());
81    }
82    return result;
83}
84
85EMarqueeDirection RenderMarquee::direction() const
86{
87    // FIXME: Support the CSS3 "auto" value for determining the direction of the marquee.
88    // For now just map MAUTO to MBACKWARD
89    EMarqueeDirection result = m_layer->renderer()->style()->marqueeDirection();
90    TextDirection dir = m_layer->renderer()->style()->direction();
91    if (result == MAUTO)
92        result = MBACKWARD;
93    if (result == MFORWARD)
94        result = (dir == LTR) ? MRIGHT : MLEFT;
95    if (result == MBACKWARD)
96        result = (dir == LTR) ? MLEFT : MRIGHT;
97
98    // Now we have the real direction.  Next we check to see if the increment is negative.
99    // If so, then we reverse the direction.
100    Length increment = m_layer->renderer()->style()->marqueeIncrement();
101    if (increment.isNegative())
102        result = static_cast<EMarqueeDirection>(-result);
103
104    return result;
105}
106
107bool RenderMarquee::isHorizontal() const
108{
109    return direction() == MLEFT || direction() == MRIGHT;
110}
111
112int RenderMarquee::computePosition(EMarqueeDirection dir, bool stopAtContentEdge)
113{
114    RenderBox* box = m_layer->renderBox();
115    ASSERT(box);
116    RenderStyle* s = box->style();
117    if (isHorizontal()) {
118        bool ltr = s->isLeftToRightDirection();
119        LayoutUnit clientWidth = box->clientWidth();
120        LayoutUnit contentWidth = ltr ? box->maxPreferredLogicalWidth() : box->minPreferredLogicalWidth();
121        if (ltr)
122            contentWidth += (box->paddingRight() - box->borderLeft());
123        else {
124            contentWidth = box->width() - contentWidth;
125            contentWidth += (box->paddingLeft() - box->borderRight());
126        }
127        if (dir == MRIGHT) {
128            if (stopAtContentEdge)
129                return max<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
130            else
131                return ltr ? contentWidth : clientWidth;
132        }
133        else {
134            if (stopAtContentEdge)
135                return min<LayoutUnit>(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
136            else
137                return ltr ? -clientWidth : -contentWidth;
138        }
139    }
140    else {
141        int contentHeight = box->layoutOverflowRect().maxY() - box->borderTop() + box->paddingBottom();
142        int clientHeight = box->clientHeight();
143        if (dir == MUP) {
144            if (stopAtContentEdge)
145                 return min(contentHeight - clientHeight, 0);
146            else
147                return -clientHeight;
148        }
149        else {
150            if (stopAtContentEdge)
151                return max(contentHeight - clientHeight, 0);
152            else
153                return contentHeight;
154        }
155    }
156}
157
158void RenderMarquee::start()
159{
160    if (m_timer.isActive() || m_layer->renderer()->style()->marqueeIncrement().isZero())
161        return;
162
163    if (!m_suspended && !m_stopped) {
164        if (isHorizontal())
165            m_layer->scrollToOffset(IntSize(m_start, 0));
166        else
167            m_layer->scrollToOffset(IntSize(0, m_start));
168    }
169    else {
170        m_suspended = false;
171        m_stopped = false;
172    }
173
174    m_timer.startRepeating(speed() * 0.001);
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 = m_layer->renderer()->style()->marqueeBehavior();
194        m_start = computePosition(direction(), behavior == MALTERNATE);
195        m_end = computePosition(reverseDirection(), behavior == MALTERNATE || behavior == MSLIDE);
196        if (!m_stopped)
197            start();
198    }
199}
200
201void RenderMarquee::updateMarqueeStyle()
202{
203    RenderStyle* s = m_layer->renderer()->style();
204
205    if (m_direction != s->marqueeDirection() || (m_totalLoops != s->marqueeLoopCount() && m_currentLoop >= m_totalLoops))
206        m_currentLoop = 0; // When direction changes or our loopCount is a smaller number than our current loop, reset our loop.
207
208    m_totalLoops = s->marqueeLoopCount();
209    m_direction = s->marqueeDirection();
210
211    if (m_layer->renderer()->isHTMLMarquee()) {
212        // Hack for WinIE.  In WinIE, a value of 0 or lower for the loop count for SLIDE means to only do
213        // one loop.
214        if (m_totalLoops <= 0 && s->marqueeBehavior() == MSLIDE)
215            m_totalLoops = 1;
216
217        // Hack alert: Set the white-space value to nowrap for horizontal marquees with inline children, thus ensuring
218        // all the text ends up on one line by default.  Limit this hack to the <marquee> element to emulate
219        // WinIE's behavior.  Someone using CSS3 can use white-space: nowrap on their own to get this effect.
220        // Second hack alert: Set the text-align back to auto.  WinIE completely ignores text-align on the
221        // marquee element.
222        // FIXME: Bring these up with the CSS WG.
223        if (isHorizontal() && m_layer->renderer()->childrenInline()) {
224            s->setWhiteSpace(NOWRAP);
225            s->setTextAlign(TASTART);
226        }
227    }
228
229    // Legacy hack - multiple browsers default vertical marquees to 200px tall.
230    if (!isHorizontal() && s->height().isAuto())
231        s->setHeight(Length(200, Fixed));
232
233    if (speed() != marqueeSpeed()) {
234        m_speed = marqueeSpeed();
235        if (m_timer.isActive())
236            m_timer.startRepeating(speed() * 0.001);
237    }
238
239    // Check the loop count to see if we should now stop.
240    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
241    if (activate && !m_timer.isActive())
242        m_layer->renderer()->setNeedsLayout(true);
243    else if (!activate && m_timer.isActive())
244        m_timer.stop();
245}
246
247void RenderMarquee::timerFired(Timer<RenderMarquee>*)
248{
249    if (m_layer->renderer()->view()->needsLayout())
250        return;
251
252    if (m_reset) {
253        m_reset = false;
254        if (isHorizontal())
255            m_layer->scrollToXOffset(m_start);
256        else
257            m_layer->scrollToYOffset(m_start);
258        return;
259    }
260
261    RenderStyle* s = m_layer->renderer()->style();
262
263    int endPoint = m_end;
264    int range = m_end - m_start;
265    int newPos;
266    if (range == 0)
267        newPos = m_end;
268    else {
269        bool addIncrement = direction() == MUP || direction() == MLEFT;
270        bool isReversed = s->marqueeBehavior() == MALTERNATE && m_currentLoop % 2;
271        if (isReversed) {
272            // We're going in the reverse direction.
273            endPoint = m_start;
274            range = -range;
275            addIncrement = !addIncrement;
276        }
277        bool positive = range > 0;
278        int clientSize = (isHorizontal() ? m_layer->renderBox()->clientWidth() : m_layer->renderBox()->clientHeight());
279        int increment = abs(intValueForLength(m_layer->renderer()->style()->marqueeIncrement(), clientSize));
280        int currentPos = (isHorizontal() ? m_layer->scrollXOffset() : m_layer->scrollYOffset());
281        newPos =  currentPos + (addIncrement ? increment : -increment);
282        if (positive)
283            newPos = min(newPos, endPoint);
284        else
285            newPos = max(newPos, endPoint);
286    }
287
288    if (newPos == endPoint) {
289        m_currentLoop++;
290        if (m_totalLoops > 0 && m_currentLoop >= m_totalLoops)
291            m_timer.stop();
292        else if (s->marqueeBehavior() != MALTERNATE)
293            m_reset = true;
294    }
295
296    if (isHorizontal())
297        m_layer->scrollToXOffset(newPos);
298    else
299        m_layer->scrollToYOffset(newPos);
300}
301
302} // namespace WebCore
303