1/*
2 * Copyright (C) 2013 Apple Inc. All rights reserved.
3 * Copyright (C) 2013 Google Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met:
8 *
9 * * Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * * Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following disclaimer
13 * in the documentation and/or other materials provided with the
14 * distribution.
15 * * Neither the name of Google Inc. nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#pragma once
33
34#include <wtf/text/StringView.h>
35
36namespace WebCore {
37
38const int UninitializedDescriptor = -1;
39const float DefaultDensityValue = 1.0;
40
41class DescriptorParsingResult {
42public:
43 DescriptorParsingResult()
44 : m_density(UninitializedDescriptor)
45 , m_resourceWidth(UninitializedDescriptor)
46 , m_resourceHeight(UninitializedDescriptor)
47 {
48 }
49
50 bool hasDensity() const { return m_density >= 0; }
51 bool hasWidth() const { return m_resourceWidth >= 0; }
52 bool hasHeight() const { return m_resourceHeight >= 0; }
53
54 float density() const { ASSERT(hasDensity()); return m_density; }
55 unsigned resourceWidth() const { ASSERT(hasWidth()); return m_resourceWidth; }
56 unsigned resourceHeight() const { ASSERT(hasHeight()); return m_resourceHeight; }
57
58 void setResourceWidth(int width) { ASSERT(width >= 0); m_resourceWidth = (unsigned)width; }
59 void setResourceHeight(int height) { ASSERT(height >= 0); m_resourceHeight = (unsigned)height; }
60 void setDensity(float densityToSet) { ASSERT(densityToSet >= 0); m_density = densityToSet; }
61
62private:
63 float m_density;
64 int m_resourceWidth;
65 int m_resourceHeight;
66};
67
68struct ImageCandidate {
69 enum OriginAttribute {
70 SrcsetOrigin,
71 SrcOrigin
72 };
73
74 ImageCandidate()
75 : density(DefaultDensityValue)
76 , resourceWidth(UninitializedDescriptor)
77 , originAttribute(SrcsetOrigin)
78 {
79 }
80
81 ImageCandidate(const StringView& source, const DescriptorParsingResult& result, OriginAttribute originAttribute)
82 : string(source)
83 , density(result.hasDensity() ? result.density() : UninitializedDescriptor)
84 , resourceWidth(result.hasWidth() ? result.resourceWidth() : UninitializedDescriptor)
85 , originAttribute(originAttribute)
86 {
87 }
88
89 bool srcOrigin() const
90 {
91 return (originAttribute == SrcOrigin);
92 }
93
94 bool isEmpty() const
95 {
96 return string.isEmpty();
97 }
98
99 StringView string;
100 float density;
101 int resourceWidth;
102 OriginAttribute originAttribute;
103};
104
105ImageCandidate bestFitSourceForImageAttributes(float deviceScaleFactor, const AtomicString& srcAttribute, const AtomicString& srcsetAttribute, float sourceSize);
106
107Vector<ImageCandidate> parseImageCandidatesFromSrcsetAttribute(StringView attribute);
108
109} // namespace WebCore
110