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
54using namespace std;
55
56namespace WebCore {
57
58using namespace HTMLNames;
59
60RenderMarquee::RenderMarquee(RenderLayer* l)
61    : m_layer(l), m_currentLoop(0)
62    , m_totalLoops(0)
63    , m_timer(this, &RenderMarquee::timerFired)
64    , m_start(0), m_end(0), m_speed(0), m_reset(false)
65    , m_suspended(false), m_stopped(false), m_direction(MAUTO)
66{
67}
68
69int RenderMarquee::marqueeSpeed() const
70{
71    int result = m_layer->renderer()->style()->marqueeSpeed();
72    Node* n = m_layer->renderer()->node();
73    if (n && n->hasTagName(marqueeTag)) {
74        HTMLMarqueeElement* marqueeElt = static_cast<HTMLMarqueeElement*>(n);
75        result = max(result, marqueeElt->minimumDelay());
76    }
77    return result;
78}
79
80EMarqueeDirection RenderMarquee::direction() const
81{
82    // FIXME: Support the CSS3 "auto" value for determining the direction of the marquee.
83    // For now just map MAUTO to MBACKWARD
84    EMarqueeDirection result = m_layer->renderer()->style()->marqueeDirection();
85    TextDirection dir = m_layer->renderer()->style()->direction();
86    if (result == MAUTO)
87        result = MBACKWARD;
88    if (result == MFORWARD)
89        result = (dir == LTR) ? MRIGHT : MLEFT;
90    if (result == MBACKWARD)
91        result = (dir == LTR) ? MLEFT : MRIGHT;
92
93    // Now we have the real direction.  Next we check to see if the increment is negative.
94    // If so, then we reverse the direction.
95    Length increment = m_layer->renderer()->style()->marqueeIncrement();
96    if (increment.isNegative())
97        result = static_cast<EMarqueeDirection>(-result);
98
99    return result;
100}
101
102bool RenderMarquee::isHorizontal() const
103{
104    return direction() == MLEFT || direction() == MRIGHT;
105}
106
107int RenderMarquee::computePosition(EMarqueeDirection dir, bool stopAtContentEdge)
108{
109    RenderBox* box = m_layer->renderBox();
110    ASSERT(box);
111    RenderStyle* s = box->style();
112    if (isHorizontal()) {
113        bool ltr = s->direction() == LTR;
114        int clientWidth = box->clientWidth();
115        int contentWidth = ltr ? box->rightmostPosition(true, false) : box->leftmostPosition(true, false);
116        if (ltr)
117            contentWidth += (box->paddingRight() - box->borderLeft());
118        else {
119            contentWidth = box->width() - contentWidth;
120            contentWidth += (box->paddingLeft() - box->borderRight());
121        }
122        if (dir == MRIGHT) {
123            if (stopAtContentEdge)
124                return max(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
125            else
126                return ltr ? contentWidth : clientWidth;
127        }
128        else {
129            if (stopAtContentEdge)
130                return min(0, ltr ? (contentWidth - clientWidth) : (clientWidth - contentWidth));
131            else
132                return ltr ? -clientWidth : -contentWidth;
133        }
134    }
135    else {
136        int contentHeight = box->lowestPosition(true, false) -
137                            box->borderTop() + box->paddingBottom();
138        int clientHeight = box->clientHeight();
139        if (dir == MUP) {
140            if (stopAtContentEdge)
141                 return min(contentHeight - clientHeight, 0);
142            else
143                return -clientHeight;
144        }
145        else {
146            if (stopAtContentEdge)
147                return max(contentHeight - clientHeight, 0);
148            else
149                return contentHeight;
150        }
151    }
152}
153
154void RenderMarquee::start()
155{
156    if (m_timer.isActive() || m_layer->renderer()->style()->marqueeIncrement().isZero()
157#if ENABLE(WCSS) && ENABLE(XHTMLMP)
158        || (m_layer->renderer()->document()->isXHTMLMPDocument() && !m_layer->renderer()->style()->marqueeLoopCount())
159#endif
160       )
161        return;
162
163    // We may end up propagating a scroll event. It is important that we suspend events until
164    // the end of the function since they could delete the layer, including the marquee.
165    FrameView* frameView = m_layer->renderer()->document()->view();
166    if (frameView)
167        frameView->pauseScheduledEvents();
168
169    if (!m_suspended && !m_stopped) {
170        if (isHorizontal())
171            m_layer->scrollToOffset(m_start, 0, false, false);
172        else
173            m_layer->scrollToOffset(0, m_start, false, false);
174    }
175    else {
176        m_suspended = false;
177        m_stopped = false;
178    }
179
180    m_timer.startRepeating(speed() * 0.001);
181
182    if (frameView)
183        frameView->resumeScheduledEvents();
184}
185
186void RenderMarquee::suspend()
187{
188    m_timer.stop();
189    m_suspended = true;
190}
191
192void RenderMarquee::stop()
193{
194    m_timer.stop();
195    m_stopped = true;
196}
197
198void RenderMarquee::updateMarqueePosition()
199{
200    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
201    if (activate) {
202        EMarqueeBehavior behavior = m_layer->renderer()->style()->marqueeBehavior();
203        m_start = computePosition(direction(), behavior == MALTERNATE);
204        m_end = computePosition(reverseDirection(), behavior == MALTERNATE || behavior == MSLIDE);
205        if (!m_stopped)
206            start();
207    }
208}
209
210void RenderMarquee::updateMarqueeStyle()
211{
212    RenderStyle* s = m_layer->renderer()->style();
213
214    if (m_direction != s->marqueeDirection() || (m_totalLoops != s->marqueeLoopCount() && m_currentLoop >= m_totalLoops))
215        m_currentLoop = 0; // When direction changes or our loopCount is a smaller number than our current loop, reset our loop.
216
217    m_totalLoops = s->marqueeLoopCount();
218    m_direction = s->marqueeDirection();
219
220    if (m_layer->renderer()->isHTMLMarquee()) {
221        // Hack for WinIE.  In WinIE, a value of 0 or lower for the loop count for SLIDE means to only do
222        // one loop.
223        if (m_totalLoops <= 0 && s->marqueeBehavior() == MSLIDE)
224            m_totalLoops = 1;
225
226        // Hack alert: Set the white-space value to nowrap for horizontal marquees with inline children, thus ensuring
227        // all the text ends up on one line by default.  Limit this hack to the <marquee> element to emulate
228        // WinIE's behavior.  Someone using CSS3 can use white-space: nowrap on their own to get this effect.
229        // Second hack alert: Set the text-align back to auto.  WinIE completely ignores text-align on the
230        // marquee element.
231        // FIXME: Bring these up with the CSS WG.
232        if (isHorizontal() && m_layer->renderer()->childrenInline()) {
233            s->setWhiteSpace(NOWRAP);
234            s->setTextAlign(TAAUTO);
235        }
236    }
237
238    // Marquee height hack!! Make sure that, if it is a horizontal marquee, the height attribute is overridden
239    // if it is smaller than the font size. If it is a vertical marquee and height is not specified, we default
240    // to a marquee of 200px.
241    if (isHorizontal()) {
242        if (s->height().isFixed() && s->height().value() < s->fontSize())
243            s->setHeight(Length(s->fontSize(), Fixed));
244    } else if (s->height().isAuto())  //vertical marquee with no specified height
245        s->setHeight(Length(200, Fixed));
246
247    if (speed() != marqueeSpeed()) {
248        m_speed = marqueeSpeed();
249        if (m_timer.isActive())
250            m_timer.startRepeating(speed() * 0.001);
251    }
252
253    // Check the loop count to see if we should now stop.
254    bool activate = (m_totalLoops <= 0 || m_currentLoop < m_totalLoops);
255    if (activate && !m_timer.isActive())
256        m_layer->renderer()->setNeedsLayout(true);
257    else if (!activate && m_timer.isActive())
258        m_timer.stop();
259}
260
261void RenderMarquee::timerFired(Timer<RenderMarquee>*)
262{
263    if (m_layer->renderer()->needsLayout())
264        return;
265
266    if (m_reset) {
267        m_reset = false;
268        if (isHorizontal())
269            m_layer->scrollToXOffset(m_start);
270        else
271            m_layer->scrollToYOffset(m_start);
272        return;
273    }
274
275    RenderStyle* s = m_layer->renderer()->style();
276
277    int endPoint = m_end;
278    int range = m_end - m_start;
279    int newPos;
280    if (range == 0)
281        newPos = m_end;
282    else {
283        bool addIncrement = direction() == MUP || direction() == MLEFT;
284        bool isReversed = s->marqueeBehavior() == MALTERNATE && m_currentLoop % 2;
285        if (isReversed) {
286            // We're going in the reverse direction.
287            endPoint = m_start;
288            range = -range;
289            addIncrement = !addIncrement;
290        }
291        bool positive = range > 0;
292        int clientSize = (isHorizontal() ? m_layer->renderBox()->clientWidth() : m_layer->renderBox()->clientHeight());
293        int increment = max(1, abs(m_layer->renderer()->style()->marqueeIncrement().calcValue(clientSize)));
294        int currentPos = (isHorizontal() ? m_layer->scrollXOffset() : m_layer->scrollYOffset());
295        newPos =  currentPos + (addIncrement ? increment : -increment);
296        if (positive)
297            newPos = min(newPos, endPoint);
298        else
299            newPos = max(newPos, endPoint);
300    }
301
302    if (newPos == endPoint) {
303        m_currentLoop++;
304        if (m_totalLoops > 0 && m_currentLoop >= m_totalLoops)
305            m_timer.stop();
306        else if (s->marqueeBehavior() != MALTERNATE)
307            m_reset = true;
308    }
309
310    if (isHorizontal())
311        m_layer->scrollToXOffset(newPos);
312    else
313        m_layer->scrollToYOffset(newPos);
314}
315
316} // namespace WebCore
317