1/*
2 * Copyright (C) 2008 Apple 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef SMILTime_h
27#define SMILTime_h
28
29#include "wtf/Assertions.h"
30#include "wtf/HashTraits.h"
31#include "wtf/MathExtras.h"
32
33namespace blink {
34
35class SMILTime {
36public:
37    SMILTime() : m_time(0) { }
38    SMILTime(double time) : m_time(time) { }
39
40    static SMILTime unresolved() { return std::numeric_limits<double>::quiet_NaN(); }
41    static SMILTime indefinite() { return std::numeric_limits<double>::infinity(); }
42
43    double value() const { return m_time; }
44
45    bool isFinite() const { return std::isfinite(m_time); }
46    bool isIndefinite() const { return std::isinf(m_time); }
47    bool isUnresolved() const { return std::isnan(m_time); }
48
49private:
50    double m_time;
51};
52
53class SMILTimeWithOrigin {
54public:
55    enum Origin {
56        ParserOrigin,
57        ScriptOrigin
58    };
59
60    SMILTimeWithOrigin()
61        : m_origin(ParserOrigin)
62    {
63    }
64
65    SMILTimeWithOrigin(const SMILTime& time, Origin origin)
66        : m_time(time)
67        , m_origin(origin)
68    {
69    }
70
71    const SMILTime& time() const { return m_time; }
72    bool originIsScript() const { return m_origin == ScriptOrigin; }
73
74private:
75    SMILTime m_time;
76    Origin m_origin;
77};
78
79struct SMILInterval {
80    SMILInterval() { }
81    SMILInterval(const SMILTime& begin, const SMILTime& end) : begin(begin), end(end) { }
82
83    SMILTime begin;
84    SMILTime end;
85};
86
87inline bool operator==(const SMILTime& a, const SMILTime& b) { return (a.isUnresolved() && b.isUnresolved()) || a.value() == b.value(); }
88inline bool operator!(const SMILTime& a) { return !a.isFinite() || !a.value(); }
89inline bool operator!=(const SMILTime& a, const SMILTime& b) { return !operator==(a, b); }
90
91// Ordering of SMILTimes has to follow: finite < indefinite (Inf) < unresolved (NaN). The first comparison is handled by IEEE754 but
92// NaN values must be checked explicitly to guarantee that unresolved is ordered correctly too.
93inline bool operator>(const SMILTime& a, const SMILTime& b) { return a.isUnresolved() || (a.value() > b.value()); }
94inline bool operator<(const SMILTime& a, const SMILTime& b) { return operator>(b, a); }
95inline bool operator>=(const SMILTime& a, const SMILTime& b) { return operator>(a, b) || operator==(a, b); }
96inline bool operator<=(const SMILTime& a, const SMILTime& b) { return operator<(a, b) || operator==(a, b); }
97inline bool operator<(const SMILTimeWithOrigin& a, const SMILTimeWithOrigin& b) { return a.time() < b.time(); }
98
99inline SMILTime operator+(const SMILTime& a, const SMILTime& b) { return a.value() + b.value(); }
100inline SMILTime operator-(const SMILTime& a, const SMILTime& b) { return a.value() - b.value(); }
101// So multiplying times does not make too much sense but SMIL defines it for duration * repeatCount
102SMILTime operator*(const SMILTime&, const SMILTime&);
103
104inline bool operator!=(const SMILInterval& a, const SMILInterval& b)
105{
106    // Compare the "raw" values since the operator!= for SMILTime always return
107    // true for non-finite times.
108    return a.begin.value() != b.begin.value() || a.end.value() != b.end.value();
109}
110
111struct SMILTimeHash {
112    static unsigned hash(const SMILTime& key) { return WTF::FloatHash<double>::hash(key.value()); }
113    static bool equal(const SMILTime& a, const SMILTime& b) { return WTF::FloatHash<double>::equal(a.value(), b.value()); }
114    static const bool safeToCompareToEmptyOrDeleted = true;
115};
116
117} // namespace blink
118
119namespace WTF {
120
121template<> struct DefaultHash<blink::SMILTime> {
122    typedef blink::SMILTimeHash Hash;
123};
124
125template<> struct HashTraits<blink::SMILTime> : GenericHashTraits<blink::SMILTime> {
126    static blink::SMILTime emptyValue() { return blink::SMILTime::unresolved(); }
127    static void constructDeletedValue(blink::SMILTime& slot, bool) { slot = -std::numeric_limits<double>::infinity(); }
128    static bool isDeletedValue(blink::SMILTime value) { return value == -std::numeric_limits<double>::infinity(); }
129};
130
131} // namespace WTF
132
133#endif // SMILTime_h
134