1/*
2 * Copyright (C) 2013 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "platform/scroll/ScrollbarThemeMacOverlayAPI.h"
33
34#include "platform/graphics/GraphicsContext.h"
35#include "platform/graphics/GraphicsContextStateSaver.h"
36#include "platform/mac/LocalCurrentGraphicsContext.h"
37#include "platform/mac/NSScrollerImpDetails.h"
38#include "platform/scroll/ScrollbarThemeClient.h"
39
40namespace WebCore {
41
42typedef HashMap<ScrollbarThemeClient*, RetainPtr<ScrollbarPainter> > ScrollbarPainterMap;
43
44static ScrollbarPainterMap* scrollbarPainterMap()
45{
46    static ScrollbarPainterMap* map = new ScrollbarPainterMap;
47    return map;
48}
49
50static bool supportsExpandedScrollbars()
51{
52    // FIXME: This is temporary until all platforms that support ScrollbarPainter support this part of the API.
53    static bool globalSupportsExpandedScrollbars = [NSClassFromString(@"NSScrollerImp") instancesRespondToSelector:@selector(setExpanded:)];
54    return globalSupportsExpandedScrollbars;
55}
56
57void ScrollbarThemeMacOverlayAPI::registerScrollbar(ScrollbarThemeClient* scrollbar)
58{
59    ScrollbarThemeMacCommon::registerScrollbar(scrollbar);
60
61    bool isHorizontal = scrollbar->orientation() == HorizontalScrollbar;
62    ScrollbarPainter scrollbarPainter = [NSClassFromString(@"NSScrollerImp") scrollerImpWithStyle:recommendedScrollerStyle() controlSize:(NSControlSize)scrollbar->controlSize() horizontal:isHorizontal replacingScrollerImp:nil];
63    scrollbarPainterMap()->add(scrollbar, scrollbarPainter);
64    updateEnabledState(scrollbar);
65    updateScrollbarOverlayStyle(scrollbar);
66}
67
68void ScrollbarThemeMacOverlayAPI::unregisterScrollbar(ScrollbarThemeClient* scrollbar)
69{
70    scrollbarPainterMap()->remove(scrollbar);
71
72    ScrollbarThemeMacCommon::unregisterScrollbar(scrollbar);
73}
74
75void ScrollbarThemeMacOverlayAPI::setNewPainterForScrollbar(ScrollbarThemeClient* scrollbar, ScrollbarPainter newPainter)
76{
77    scrollbarPainterMap()->set(scrollbar, newPainter);
78    updateEnabledState(scrollbar);
79    updateScrollbarOverlayStyle(scrollbar);
80}
81
82ScrollbarPainter ScrollbarThemeMacOverlayAPI::painterForScrollbar(ScrollbarThemeClient* scrollbar)
83{
84    return scrollbarPainterMap()->get(scrollbar).get();
85}
86
87void ScrollbarThemeMacOverlayAPI::paintTrackBackground(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect) {
88    ASSERT(isOverlayAPIAvailable());
89
90    GraphicsContextStateSaver stateSaver(*context);
91    context->translate(rect.x(), rect.y());
92    LocalCurrentGraphicsContext localContext(context);
93
94    CGRect frameRect = scrollbar->frameRect();
95    ScrollbarPainter scrollbarPainter = painterForScrollbar(scrollbar);
96    [scrollbarPainter setEnabled:scrollbar->enabled()];
97    [scrollbarPainter setBoundsSize: NSSizeFromCGSize(frameRect.size)];
98
99    NSRect trackRect = NSMakeRect(0, 0, frameRect.size.width, frameRect.size.height);
100    [scrollbarPainter drawKnobSlotInRect:trackRect highlight:NO];
101}
102
103void ScrollbarThemeMacOverlayAPI::paintThumb(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect) {
104    ASSERT(isOverlayAPIAvailable());
105
106    GraphicsContextStateSaver stateSaver(*context);
107    context->translate(rect.x(), rect.y());
108    LocalCurrentGraphicsContext localContext(context);
109
110    ScrollbarPainter scrollbarPainter = painterForScrollbar(scrollbar);
111    [scrollbarPainter setEnabled:scrollbar->enabled()];
112    [scrollbarPainter setBoundsSize:NSSizeFromCGSize(rect.size())];
113    [scrollbarPainter setDoubleValue:0];
114    [scrollbarPainter setKnobProportion:1];
115    if (scrollbar->enabled())
116        [scrollbarPainter drawKnob];
117
118    // If this state is not set, then moving the cursor over the scrollbar area will only cause the
119    // scrollbar to engorge when moved over the top of the scrollbar area.
120    [scrollbarPainter setBoundsSize: NSSizeFromCGSize(scrollbar->frameRect().size())];
121}
122
123int ScrollbarThemeMacOverlayAPI::scrollbarThickness(ScrollbarControlSize controlSize)
124{
125    ScrollbarPainter scrollbarPainter = [NSClassFromString(@"NSScrollerImp") scrollerImpWithStyle:recommendedScrollerStyle() controlSize:controlSize horizontal:NO replacingScrollerImp:nil];
126    if (supportsExpandedScrollbars())
127        [scrollbarPainter setExpanded:YES];
128    return [scrollbarPainter trackBoxWidth];
129}
130
131bool ScrollbarThemeMacOverlayAPI::usesOverlayScrollbars() const
132{
133    return recommendedScrollerStyle() == NSScrollerStyleOverlay;
134}
135
136void ScrollbarThemeMacOverlayAPI::updateScrollbarOverlayStyle(ScrollbarThemeClient* scrollbar)
137{
138    ScrollbarPainter painter = painterForScrollbar(scrollbar);
139    switch (scrollbar->scrollbarOverlayStyle()) {
140    case ScrollbarOverlayStyleDefault:
141        [painter setKnobStyle:NSScrollerKnobStyleDefault];
142        break;
143    case ScrollbarOverlayStyleDark:
144        [painter setKnobStyle:NSScrollerKnobStyleDark];
145        break;
146    case ScrollbarOverlayStyleLight:
147        [painter setKnobStyle:NSScrollerKnobStyleLight];
148        break;
149    }
150}
151
152ScrollbarButtonsPlacement ScrollbarThemeMacOverlayAPI::buttonsPlacement() const
153{
154    return ScrollbarButtonsNone;
155}
156
157bool ScrollbarThemeMacOverlayAPI::hasThumb(ScrollbarThemeClient* scrollbar)
158{
159    ScrollbarPainter painter = painterForScrollbar(scrollbar);
160    int minLengthForThumb = [painter knobMinLength] + [painter trackOverlapEndInset] + [painter knobOverlapEndInset]
161        + 2 * ([painter trackEndInset] + [painter knobEndInset]);
162    return scrollbar->enabled() && (scrollbar->orientation() == HorizontalScrollbar ?
163             scrollbar->width() :
164             scrollbar->height()) >= minLengthForThumb;
165}
166
167IntRect ScrollbarThemeMacOverlayAPI::backButtonRect(ScrollbarThemeClient* scrollbar, ScrollbarPart part, bool painting)
168{
169    ASSERT(buttonsPlacement() == ScrollbarButtonsNone);
170    return IntRect();
171}
172
173IntRect ScrollbarThemeMacOverlayAPI::forwardButtonRect(ScrollbarThemeClient* scrollbar, ScrollbarPart part, bool painting)
174{
175    ASSERT(buttonsPlacement() == ScrollbarButtonsNone);
176    return IntRect();
177}
178
179IntRect ScrollbarThemeMacOverlayAPI::trackRect(ScrollbarThemeClient* scrollbar, bool painting)
180{
181    ASSERT(!hasButtons(scrollbar));
182    return scrollbar->frameRect();
183}
184
185int ScrollbarThemeMacOverlayAPI::minimumThumbLength(ScrollbarThemeClient* scrollbar)
186{
187    return [painterForScrollbar(scrollbar) knobMinLength];
188}
189
190void ScrollbarThemeMacOverlayAPI::updateEnabledState(ScrollbarThemeClient* scrollbar)
191{
192    [painterForScrollbar(scrollbar) setEnabled:scrollbar->enabled()];
193}
194
195} // namespace WebCore
196