1 /*
2 * Copyright (C) 2012 Motorola Mobility 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 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Motorola Mobility Inc. nor the names of its
14 * contributors may be used to endorse or promote products derived from this
15 * software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "config.h"
31 #include "DOMWindowCSS.h"
32
33 #include "CSSParser.h"
34 #include "StyleProperties.h"
35 #include <wtf/text/WTFString.h>
36
37 namespace WebCore {
38
39 Ref<DOMWindowCSS> DOMWindowCSS::create()
40 {
41 return adoptRef(*new DOMWindowCSS);
42 }
43
44 static String valueWithoutImportant(const String& value)
45 {
46 if (!value.endsWith("important", false))
47 return value;
48
49 String newValue = value;
50 int bangIndex = newValue.length() - 9 - 1;
51 if (newValue[bangIndex] == ' ')
52 bangIndex--;
53 newValue = newValue.left(bangIndex);
54
55 return newValue;
56 }
57
58 bool DOMWindowCSS::supports(const String& property, const String& value) const
59 {
60 CSSPropertyID propertyID = cssPropertyID(property.stripWhiteSpace());
61
62 if (propertyID == CSSPropertyInvalid)
63 return false;
64
65 // CSSParser::parseValue() won't work correctly if !important is present,
66 // so just get rid of it. It doesn't matter to supports() if it's actually
67 // there or not, provided how it's specified in the value is correct.
68 String normalizedValue = value.stripWhiteSpace().simplifyWhiteSpace();
69 normalizedValue = valueWithoutImportant(normalizedValue);
70
71 if (normalizedValue.isEmpty())
72 return false;
73
74 RefPtr<MutableStyleProperties> dummyStyle = MutableStyleProperties::create();
75 return CSSParser::parseValue(dummyStyle.get(), propertyID, normalizedValue, false, CSSStrictMode, nullptr) != CSSParser::ParseResult::Error;
76 }
77
78 bool DOMWindowCSS::supports(const String& conditionText) const
79 {
80 CSSParserContext context(CSSStrictMode);
81 CSSParser parser(context);
82 return parser.parseSupportsCondition(conditionText);
83 }
84
85 }