1/*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
4 * Copyright (C) 2012 Google Inc. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1.  Redistributions of source code must retain the above copyright
10 *     notice, this list of conditions and the following disclaimer.
11 * 2.  Redistributions in binary form must reproduce the above copyright
12 *     notice, this list of conditions and the following disclaimer in the
13 *     documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
16 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
22 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef ScopedStyleTree_h
28#define ScopedStyleTree_h
29
30#include "core/css/resolver/ScopedStyleResolver.h"
31#include "wtf/HashMap.h"
32#include "wtf/OwnPtr.h"
33#include "wtf/Vector.h"
34
35namespace WebCore {
36
37class ScopedStyleTree {
38    WTF_MAKE_NONCOPYABLE(ScopedStyleTree); WTF_MAKE_FAST_ALLOCATED;
39public:
40    ScopedStyleTree() : m_scopedResolverForDocument(0), m_buildInDocumentOrder(true) { }
41
42    ScopedStyleResolver* ensureScopedStyleResolver(ContainerNode& scopingNode);
43    ScopedStyleResolver* lookupScopedStyleResolverFor(const ContainerNode* scopingNode)
44    {
45        HashMap<const ContainerNode*, OwnPtr<ScopedStyleResolver> >::iterator it = m_authorStyles.find(scopingNode);
46        return it != m_authorStyles.end() ? it->value.get() : 0;
47    }
48
49    ScopedStyleResolver* scopedStyleResolverFor(const ContainerNode& scopingNode);
50    ScopedStyleResolver* addScopedStyleResolver(ContainerNode& scopingNode, bool& isNewEntry);
51    void clear();
52
53    // for fast-path.
54    bool hasOnlyScopedResolverForDocument() const { return m_scopedResolverForDocument && m_authorStyles.size() == 1; }
55    ScopedStyleResolver* scopedStyleResolverForDocument() const { return m_scopedResolverForDocument; }
56
57    void resolveScopedStyles(const Element*, Vector<ScopedStyleResolver*, 8>&);
58    void collectScopedResolversForHostedShadowTrees(const Element*, Vector<ScopedStyleResolver*, 8>&);
59    void resolveScopedKeyframesRules(const Element*, Vector<ScopedStyleResolver*, 8>&);
60    ScopedStyleResolver* scopedResolverFor(const Element*);
61
62    void remove(const ContainerNode* scopingNode);
63
64    void pushStyleCache(const ContainerNode& scopingNode, const ContainerNode* parent);
65    void popStyleCache(const ContainerNode& scopingNode);
66
67    void collectFeaturesTo(RuleFeatureSet& features);
68    void setBuildInDocumentOrder(bool enabled) { m_buildInDocumentOrder = enabled; }
69    bool buildInDocumentOrder() const { return m_buildInDocumentOrder; }
70
71private:
72    void setupScopedStylesTree(ScopedStyleResolver* target);
73
74    bool cacheIsValid(const ContainerNode* parent) const { return parent && parent == m_cache.nodeForScopedStyles; }
75    void resolveStyleCache(const ContainerNode* scopingNode);
76    ScopedStyleResolver* enclosingScopedStyleResolverFor(const ContainerNode* scopingNode);
77
78    void reparentNodes(const ScopedStyleResolver* oldParent, ScopedStyleResolver* newParent);
79
80private:
81    HashMap<const ContainerNode*, OwnPtr<ScopedStyleResolver> > m_authorStyles;
82    ScopedStyleResolver* m_scopedResolverForDocument;
83    bool m_buildInDocumentOrder;
84
85    struct ScopedStyleCache {
86        ScopedStyleResolver* scopedResolver;
87        const ContainerNode* nodeForScopedStyles;
88
89        void clear()
90        {
91            scopedResolver = 0;
92            nodeForScopedStyles = 0;
93        }
94    };
95    ScopedStyleCache m_cache;
96};
97
98inline ScopedStyleResolver* ScopedStyleTree::scopedResolverFor(const Element* element)
99{
100    if (!cacheIsValid(element))
101        resolveStyleCache(element);
102
103    return m_cache.scopedResolver;
104}
105
106} // namespace WebCore
107
108#endif // ScopedStyleTree_h
109