1 /*
2 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #include "config.h"
21 #include "core/css/MediaQueryMatcher.h"
22
23 #include "core/css/MediaList.h"
24 #include "core/css/MediaQueryEvaluator.h"
25 #include "core/css/MediaQueryList.h"
26 #include "core/css/MediaQueryListListener.h"
27 #include "core/css/resolver/StyleResolver.h"
28 #include "core/dom/Document.h"
29 #include "core/frame/Frame.h"
30 #include "core/frame/FrameView.h"
31
32 namespace WebCore {
33
Listener(PassRefPtr<MediaQueryListListener> listener,PassRefPtr<MediaQueryList> query)34 MediaQueryMatcher::Listener::Listener(PassRefPtr<MediaQueryListListener> listener, PassRefPtr<MediaQueryList> query)
35 : m_listener(listener)
36 , m_query(query)
37 {
38 }
39
~Listener()40 MediaQueryMatcher::Listener::~Listener()
41 {
42 }
43
evaluate(ScriptState * state,MediaQueryEvaluator * evaluator)44 void MediaQueryMatcher::Listener::evaluate(ScriptState* state, MediaQueryEvaluator* evaluator)
45 {
46 bool notify;
47 m_query->evaluate(evaluator, notify);
48 if (notify)
49 m_listener->queryChanged(state, m_query.get());
50 }
51
MediaQueryMatcher(Document * document)52 MediaQueryMatcher::MediaQueryMatcher(Document* document)
53 : m_document(document)
54 , m_evaluationRound(1)
55 {
56 ASSERT(m_document);
57 }
58
~MediaQueryMatcher()59 MediaQueryMatcher::~MediaQueryMatcher()
60 {
61 }
62
documentDestroyed()63 void MediaQueryMatcher::documentDestroyed()
64 {
65 m_listeners.clear();
66 m_document = 0;
67 }
68
mediaType() const69 AtomicString MediaQueryMatcher::mediaType() const
70 {
71 if (!m_document || !m_document->frame() || !m_document->frame()->view())
72 return nullAtom;
73
74 return m_document->frame()->view()->mediaType();
75 }
76
prepareEvaluator() const77 PassOwnPtr<MediaQueryEvaluator> MediaQueryMatcher::prepareEvaluator() const
78 {
79 if (!m_document || !m_document->frame())
80 return nullptr;
81
82 Element* documentElement = m_document->documentElement();
83 if (!documentElement)
84 return nullptr;
85
86 StyleResolver& styleResolver = m_document->ensureStyleResolver();
87 RefPtr<RenderStyle> rootStyle = styleResolver.styleForElement(documentElement, 0 /*defaultParent*/, DisallowStyleSharing, MatchOnlyUserAgentRules);
88
89 return adoptPtr(new MediaQueryEvaluator(mediaType(), m_document->frame(), rootStyle.get()));
90 }
91
evaluate(const MediaQuerySet * media)92 bool MediaQueryMatcher::evaluate(const MediaQuerySet* media)
93 {
94 if (!media)
95 return false;
96
97 OwnPtr<MediaQueryEvaluator> evaluator(prepareEvaluator());
98 return evaluator && evaluator->eval(media);
99 }
100
matchMedia(const String & query)101 PassRefPtr<MediaQueryList> MediaQueryMatcher::matchMedia(const String& query)
102 {
103 if (!m_document)
104 return 0;
105
106 RefPtr<MediaQuerySet> media = MediaQuerySet::create(query);
107 // Add warning message to inspector whenever dpi/dpcm values are used for "screen" media.
108 reportMediaQueryWarningIfNeeded(m_document, media.get());
109 return MediaQueryList::create(this, media, evaluate(media.get()));
110 }
111
addListener(PassRefPtr<MediaQueryListListener> listener,PassRefPtr<MediaQueryList> query)112 void MediaQueryMatcher::addListener(PassRefPtr<MediaQueryListListener> listener, PassRefPtr<MediaQueryList> query)
113 {
114 if (!m_document)
115 return;
116
117 for (size_t i = 0; i < m_listeners.size(); ++i) {
118 if (*m_listeners[i]->listener() == *listener && m_listeners[i]->query() == query)
119 return;
120 }
121
122 m_listeners.append(adoptPtr(new Listener(listener, query)));
123 }
124
removeListener(MediaQueryListListener * listener,MediaQueryList * query)125 void MediaQueryMatcher::removeListener(MediaQueryListListener* listener, MediaQueryList* query)
126 {
127 if (!m_document)
128 return;
129
130 for (size_t i = 0; i < m_listeners.size(); ++i) {
131 if (*m_listeners[i]->listener() == *listener && m_listeners[i]->query() == query) {
132 m_listeners.remove(i);
133 return;
134 }
135 }
136 }
137
styleResolverChanged()138 void MediaQueryMatcher::styleResolverChanged()
139 {
140 if (!m_document)
141 return;
142
143 ScriptState* scriptState = m_document->frame() ? mainWorldScriptState(m_document->frame()) : 0;
144 if (!scriptState)
145 return;
146
147 ++m_evaluationRound;
148 OwnPtr<MediaQueryEvaluator> evaluator = prepareEvaluator();
149 if (!evaluator)
150 return;
151
152 for (size_t i = 0; i < m_listeners.size(); ++i)
153 m_listeners[i]->evaluate(scriptState, evaluator.get());
154 }
155
156 }
157