1/*
2 * Copyright (C) 2009 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 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
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15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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29 */
30
31#ifndef DateComponents_h
32#define DateComponents_h
33
34#include <limits>
35#include "platform/PlatformExport.h"
36#include "wtf/Forward.h"
37#include "wtf/unicode/Unicode.h"
38
39namespace WebCore {
40
41// A DateComponents instance represents one of the following date and time combinations:
42// * Month type: year-month
43// * Date type: year-month-day
44// * Week type: year-week
45// * Time type: hour-minute-second-millisecond
46// * DateTime or DateTimeLocal type: year-month-day hour-minute-second-millisecond
47class PLATFORM_EXPORT DateComponents {
48public:
49    DateComponents()
50        : m_millisecond(0)
51        , m_second(0)
52        , m_minute(0)
53        , m_hour(0)
54        , m_monthDay(0)
55        , m_month(0)
56        , m_year(0)
57        , m_week(0)
58        , m_type(Invalid)
59    {
60    }
61
62    enum Type {
63        Invalid,
64        Date,
65        DateTime,
66        DateTimeLocal,
67        Month,
68        Time,
69        Week,
70    };
71
72    int millisecond() const { return m_millisecond; }
73    int second() const { return m_second; }
74    int minute() const { return m_minute; }
75    int hour() const { return m_hour; }
76    int monthDay() const { return m_monthDay; }
77    int month() const { return m_month; }
78    int fullYear() const { return m_year; }
79    int week() const { return m_week; }
80    Type type() const { return m_type; }
81
82    enum SecondFormat {
83        None, // Suppress the second part and the millisecond part if they are 0.
84        Second, // Always show the second part, and suppress the millisecond part if it is 0.
85        Millisecond // Always show the second part and the millisecond part.
86    };
87
88    // Returns an ISO 8601 representation for this instance.
89    // The format argument is valid for DateTime, DateTimeLocal, and Time types.
90    String toString(SecondFormat format = None) const;
91
92    // parse*() and setMillisecondsSince*() functions are initializers for an
93    // DateComponents instance. If these functions return false, the instance
94    // might be invalid.
95
96    // The following six functions parse the input 'src' whose length is
97    // 'length', and updates some fields of this instance. The parsing starts at
98    // src[start] and examines characters before src[length].
99    // 'src' must be non-null. The 'src' string doesn't need to be
100    // null-terminated.
101    // The functions return true if the parsing succeeds, and set 'end' to the
102    // next index after the last consumed. Extra leading characters cause parse
103    // failures, and the trailing extra characters don't cause parse failures.
104
105    // Sets year and month.
106    bool parseMonth(const String&, unsigned start, unsigned& end);
107    // Sets year, month and monthDay.
108    bool parseDate(const String&, unsigned start, unsigned& end);
109    // Sets year and week.
110    bool parseWeek(const String&, unsigned start, unsigned& end);
111    // Sets hour, minute, second and millisecond.
112    bool parseTime(const String&, unsigned start, unsigned& end);
113    // Sets year, month, monthDay, hour, minute, second and millisecond.
114    bool parseDateTimeLocal(const String&, unsigned start, unsigned& end);
115    // Sets year, month, monthDay, hour, minute, second and millisecond, and adjusts timezone.
116    bool parseDateTime(const String&, unsigned start, unsigned& end);
117
118    // The following setMillisecondsSinceEpochFor*() functions take
119    // the number of milliseconds since 1970-01-01 00:00:00.000 UTC as
120    // the argument, and update all fields for the corresponding
121    // DateComponents type. The functions return true if it succeeds, and
122    // false if they fail.
123
124    // For Date type. Updates m_year, m_month and m_monthDay.
125    bool setMillisecondsSinceEpochForDate(double ms);
126    // For DateTime type. Updates m_year, m_month, m_monthDay, m_hour, m_minute, m_second and m_millisecond.
127    bool setMillisecondsSinceEpochForDateTime(double ms);
128    // For DateTimeLocal type. Updates m_year, m_month, m_monthDay, m_hour, m_minute, m_second and m_millisecond.
129    bool setMillisecondsSinceEpochForDateTimeLocal(double ms);
130    // For Month type. Updates m_year and m_month.
131    bool setMillisecondsSinceEpochForMonth(double ms);
132    // For Week type. Updates m_year and m_week.
133    bool setMillisecondsSinceEpochForWeek(double ms);
134
135    // For Time type. Updates m_hour, m_minute, m_second and m_millisecond.
136    bool setMillisecondsSinceMidnight(double ms);
137
138    // Another initializer for Month type. Updates m_year and m_month.
139    bool setMonthsSinceEpoch(double months);
140
141    // Returns the number of milliseconds from 1970-01-01 00:00:00 UTC.
142    // For a DateComponents initialized with parseDateTimeLocal(),
143    // millisecondsSinceEpoch() returns a value for UTC timezone.
144    double millisecondsSinceEpoch() const;
145    // Returns the number of months from 1970-01.
146    // Do not call this for types other than Month.
147    double monthsSinceEpoch() const;
148    static inline double invalidMilliseconds() { return std::numeric_limits<double>::quiet_NaN(); }
149
150    // Minimum and maxmimum limits for setMillisecondsSince*(),
151    // setMonthsSinceEpoch(), millisecondsSinceEpoch(), and monthsSinceEpoch().
152    static inline double minimumDate() { return -62135596800000.0; } // 0001-01-01T00:00Z
153    static inline double minimumDateTime() { return -62135596800000.0; } // ditto.
154    static inline double minimumMonth() { return (1 - 1970) * 12.0 + 1 - 1; } // 0001-01
155    static inline double minimumTime() { return 0; } // 00:00:00.000
156    static inline double minimumWeek() { return -62135596800000.0; } // 0001-01-01, the first Monday of 0001.
157    static inline double maximumDate() { return 8640000000000000.0; } // 275760-09-13T00:00Z
158    static inline double maximumDateTime() { return 8640000000000000.0; } // ditto.
159    static inline double maximumMonth() { return (275760 - 1970) * 12.0 + 9 - 1; } // 275760-09
160    static inline double maximumTime() { return 86399999; } // 23:59:59.999
161    static inline double maximumWeek() { return 8639999568000000.0; } // 275760-09-08, the Monday of the week including 275760-09-13.
162
163    // HTML5 uses ISO-8601 format with year >= 1. Gregorian calendar started in
164    // 1582. However, we need to support 0001-01-01 in Gregorian calendar rule.
165    static inline int minimumYear() { return 1; }
166    // Date in ECMAScript can't represent dates later than 275760-09-13T00:00Z.
167    // So, we have the same upper limit in HTML5 date/time types.
168    static inline int maximumYear() { return 275760; }
169    static const int minimumWeekNumber;
170    static const int maximumWeekNumber;
171
172private:
173    // Returns the maximum week number in this DateComponents's year.
174    // The result is either of 52 and 53.
175    int maxWeekNumberInYear() const;
176    bool parseYear(const String&, unsigned start, unsigned& end);
177    bool addDay(int);
178    bool addMinute(int);
179    bool parseTimeZone(const String&, unsigned start, unsigned& end);
180    // Helper for millisecondsSinceEpoch().
181    double millisecondsSinceEpochForTime() const;
182    // Helpers for setMillisecondsSinceEpochFor*().
183    bool setMillisecondsSinceEpochForDateInternal(double ms);
184    void setMillisecondsSinceMidnightInternal(double ms);
185    // Helper for toString().
186    String toStringForTime(SecondFormat) const;
187
188    // m_weekDay values
189    enum {
190        Sunday = 0,
191        Monday,
192        Tuesday,
193        Wednesday,
194        Thursday,
195        Friday,
196        Saturday,
197    };
198
199    int m_millisecond; // 0 - 999
200    int m_second;
201    int m_minute;
202    int m_hour;
203    int m_monthDay; // 1 - 31
204    int m_month; // 0:January - 11:December
205    int m_year; //  1582 -
206    int m_week; // 1 - 53
207
208    Type m_type;
209};
210
211
212} // namespace WebCore
213
214#endif // DateComponents_h
215