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 *     * Neither the name of Google Inc. nor the names of its
11 * contributors may be used to endorse or promote products derived from
12 * this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
18 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
20 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "config.h"
28#include "core/dom/StyleSheetCandidate.h"
29
30#include "core/HTMLNames.h"
31#include "core/dom/Element.h"
32#include "core/dom/ProcessingInstruction.h"
33#include "core/dom/StyleEngine.h"
34#include "core/html/HTMLLinkElement.h"
35#include "core/html/HTMLStyleElement.h"
36#include "core/html/imports/HTMLImport.h"
37#include "core/svg/SVGStyleElement.h"
38
39namespace blink {
40
41using namespace HTMLNames;
42
43AtomicString StyleSheetCandidate::title() const
44{
45    return isElement() ? toElement(node()).fastGetAttribute(titleAttr) : nullAtom;
46}
47
48bool StyleSheetCandidate::isXSL() const
49{
50    return !node().document().isHTMLDocument() && m_type == Pi && toProcessingInstruction(node()).isXSL();
51}
52
53bool StyleSheetCandidate::isImport() const
54{
55    return m_type == HTMLLink && toHTMLLinkElement(node()).isImport();
56}
57
58Document* StyleSheetCandidate::importedDocument() const
59{
60    ASSERT(isImport());
61    return toHTMLLinkElement(node()).import();
62}
63
64bool StyleSheetCandidate::isAlternate() const
65{
66    if (!isElement())
67        return false;
68    return toElement(node()).getAttribute(relAttr).contains("alternate");
69}
70
71bool StyleSheetCandidate::isEnabledViaScript() const
72{
73    return isHTMLLink() && toHTMLLinkElement(node()).isEnabledViaScript();
74}
75
76bool StyleSheetCandidate::isEnabledAndLoading() const
77{
78    return isHTMLLink() && !toHTMLLinkElement(node()).isDisabled() && toHTMLLinkElement(node()).styleSheetIsLoading();
79}
80
81bool StyleSheetCandidate::hasPreferrableName(const String& currentPreferrableName) const
82{
83    ASSERT(isEnabledAndLoading() || sheet());
84    return !isEnabledViaScript() && !title().isEmpty() && !isAlternate() && currentPreferrableName.isEmpty();
85}
86
87bool StyleSheetCandidate::canBeActivated(const String& currentPreferrableName) const
88{
89    StyleSheet* sheet = this->sheet();
90    if (!sheet || sheet->disabled() || !sheet->isCSSStyleSheet())
91        return false;
92    const AtomicString& title = this->title();
93    if (!isEnabledViaScript() && !title.isEmpty() && title != currentPreferrableName)
94        return false;
95    if (isAlternate() && title.isEmpty())
96        return false;
97
98    return true;
99}
100
101StyleSheetCandidate::Type StyleSheetCandidate::typeOf(Node& node)
102{
103    if (node.nodeType() == Node::PROCESSING_INSTRUCTION_NODE)
104        return Pi;
105
106    if (node.isHTMLElement()) {
107        if (isHTMLLinkElement(node))
108            return HTMLLink;
109        if (isHTMLStyleElement(node))
110            return HTMLStyle;
111
112        ASSERT_NOT_REACHED();
113        return HTMLStyle;
114    }
115
116    if (isSVGStyleElement(node))
117        return SVGStyle;
118
119    ASSERT_NOT_REACHED();
120    return HTMLStyle;
121}
122
123StyleSheet* StyleSheetCandidate::sheet() const
124{
125    switch (m_type) {
126    case HTMLLink:
127        return toHTMLLinkElement(node()).sheet();
128    case HTMLStyle:
129        return toHTMLStyleElement(node()).sheet();
130    case SVGStyle:
131        return toSVGStyleElement(node()).sheet();
132    case Pi:
133        return toProcessingInstruction(node()).sheet();
134    }
135
136    ASSERT_NOT_REACHED();
137    return 0;
138}
139
140}
141