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
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef DateComponents_h
32#define DateComponents_h
33
34#include <limits>
35#include <unicode/utypes.h>
36#include <wtf/Forward.h>
37
38namespace WebCore {
39
40// A DateComponents instance represents one of the following date and time combinations:
41// * Month type: year-month
42// * Date type: year-month-day
43// * Week type: year-week
44// * Time type: hour-minute-second-millisecond
45// * DateTime or DateTimeLocal type: year-month-day hour-minute-second-millisecond
46class DateComponents {
47public:
48    DateComponents()
49        : m_millisecond(0)
50        , m_second(0)
51        , m_minute(0)
52        , m_hour(0)
53        , m_monthDay(0)
54        , m_month(0)
55        , m_year(0)
56        , m_week(0)
57        , m_type(Invalid)
58    {
59    }
60
61    enum Type {
62        Invalid,
63        Date,
64        DateTime,
65        DateTimeLocal,
66        Month,
67        Time,
68        Week,
69    };
70
71    int millisecond() const { return m_millisecond; }
72    int second() const { return m_second; }
73    int minute() const { return m_minute; }
74    int hour() const { return m_hour; }
75    int monthDay() const { return m_monthDay; }
76    int month() const { return m_month; }
77    int fullYear() const { return m_year; }
78    int week() const { return m_week; }
79    Type type() const { return m_type; }
80
81    enum SecondFormat {
82        None, // Suppress the second part and the millisecond part if they are 0.
83        Second, // Always show the second part, and suppress the millisecond part if it is 0.
84        Millisecond // Always show the second part and the millisecond part.
85    };
86
87    // Returns an ISO 8601 representation for this instance.
88    // The format argument is valid for DateTime, DateTimeLocal, and Time types.
89    String toString(SecondFormat format = None) const;
90
91    // parse*() and setMillisecondsSince*() functions are initializers for an
92    // DateComponents instance. If these functions return false, the instance
93    // might be invalid.
94
95    // The following six functions parse the input 'src' whose length is
96    // 'length', and updates some fields of this instance. The parsing starts at
97    // src[start] and examines characters before src[length].
98    // 'src' must be non-null. The 'src' string doesn't need to be
99    // null-terminated.
100    // The functions return true if the parsing succeeds, and set 'end' to the
101    // next index after the last consumed. Extra leading characters cause parse
102    // failures, and the trailing extra characters don't cause parse failures.
103
104    // Sets year and month.
105    bool parseMonth(const UChar* src, unsigned length, unsigned start, unsigned& end);
106    // Sets year, month and monthDay.
107    bool parseDate(const UChar* src, unsigned length, unsigned start, unsigned& end);
108    // Sets year and week.
109    bool parseWeek(const UChar* src, unsigned length, unsigned start, unsigned& end);
110    // Sets hour, minute, second and millisecond.
111    bool parseTime(const UChar* src, unsigned length, unsigned start, unsigned& end);
112    // Sets year, month, monthDay, hour, minute, second and millisecond.
113    bool parseDateTimeLocal(const UChar* src, unsigned length, unsigned start, unsigned& end);
114    // Sets year, month, monthDay, hour, minute, second and millisecond, and adjusts timezone.
115    bool parseDateTime(const UChar* src, unsigned length, unsigned start, unsigned& end);
116
117    // The following setMillisecondsSinceEpochFor*() functions take
118    // the number of milliseconds since 1970-01-01 00:00:00.000 UTC as
119    // the argument, and update all fields for the corresponding
120    // DateComponents type. The functions return true if it succeeds, and
121    // false if they fail.
122
123    // For Date type. Updates m_year, m_month and m_monthDay.
124    bool setMillisecondsSinceEpochForDate(double ms);
125    // For DateTime type. Updates m_year, m_month, m_monthDay, m_hour, m_minute, m_second and m_millisecond.
126    bool setMillisecondsSinceEpochForDateTime(double ms);
127    // For DateTimeLocal type. Updates m_year, m_month, m_monthDay, m_hour, m_minute, m_second and m_millisecond.
128    bool setMillisecondsSinceEpochForDateTimeLocal(double ms);
129    // For Month type. Updates m_year and m_month.
130    bool setMillisecondsSinceEpochForMonth(double ms);
131    // For Week type. Updates m_year and m_week.
132    bool setMillisecondsSinceEpochForWeek(double ms);
133
134    // For Time type. Updates m_hour, m_minute, m_second and m_millisecond.
135    bool setMillisecondsSinceMidnight(double ms);
136
137    // Another initializer for Month type. Updates m_year and m_month.
138    bool setMonthsSinceEpoch(double months);
139
140    // Returns the number of milliseconds from 1970-01-01 00:00:00 UTC.
141    // For a DateComponents initialized with parseDateTimeLocal(),
142    // millisecondsSinceEpoch() returns a value for UTC timezone.
143    double millisecondsSinceEpoch() const;
144    // Returns the number of months from 1970-01.
145    // Do not call this for types other than Month.
146    double monthsSinceEpoch() const;
147    static inline double invalidMilliseconds() { return std::numeric_limits<double>::quiet_NaN(); }
148
149    // Minimum and maxmimum limits for setMillisecondsSince*(),
150    // setMonthsSinceEpoch(), millisecondsSinceEpoch(), and monthsSinceEpoch().
151    static inline double minimumDate() { return -62135596800000.0; } // 0001-01-01T00:00Z
152    static inline double minimumDateTime() { return -62135596800000.0; } // ditto.
153    static inline double minimumMonth() { return (1 - 1970) * 12.0 + 1 - 1; } // 0001-01
154    static inline double minimumTime() { return 0; } // 00:00:00.000
155    static inline double minimumWeek() { return -62135596800000.0; } // 0001-01-01, the first Monday of 0001.
156    static inline double maximumDate() { return 8640000000000000.0; } // 275760-09-13T00:00Z
157    static inline double maximumDateTime() { return 8640000000000000.0; } // ditto.
158    static inline double maximumMonth() { return (275760 - 1970) * 12.0 + 9 - 1; } // 275760-09
159    static inline double maximumTime() { return 86399999; } // 23:59:59.999
160    static inline double maximumWeek() { return 8639999568000000.0; } // 275760-09-08, the Monday of the week including 275760-09-13.
161
162    // HTML5 uses ISO-8601 format with year >= 1. Gregorian calendar started in
163    // 1582. However, we need to support 0001-01-01 in Gregorian calendar rule.
164    static inline int minimumYear() { return 1; }
165    // Date in ECMAScript can't represent dates later than 275760-09-13T00:00Z.
166    // So, we have the same upper limit in HTML5 date/time types.
167    static inline int maximumYear() { return 275760; }
168    static const int minimumWeekNumber;
169    static const int maximumWeekNumber;
170
171private:
172    // Returns the maximum week number in this DateComponents's year.
173    // The result is either of 52 and 53.
174    int maxWeekNumberInYear() const;
175    bool parseYear(const UChar* src, unsigned length, unsigned start, unsigned& end);
176    bool addDay(int);
177    bool addMinute(int);
178    bool parseTimeZone(const UChar* src, unsigned length, unsigned start, unsigned& end);
179    // Helper for millisecondsSinceEpoch().
180    double millisecondsSinceEpochForTime() const;
181    // Helpers for setMillisecondsSinceEpochFor*().
182    bool setMillisecondsSinceEpochForDateInternal(double ms);
183    void setMillisecondsSinceMidnightInternal(double ms);
184    // Helper for toString().
185    String toStringForTime(SecondFormat) const;
186
187    // m_weekDay values
188    enum {
189        Sunday = 0,
190        Monday,
191        Tuesday,
192        Wednesday,
193        Thursday,
194        Friday,
195        Saturday,
196    };
197
198    int m_millisecond; // 0 - 999
199    int m_second;
200    int m_minute;
201    int m_hour;
202    int m_monthDay; // 1 - 31
203    int m_month; // 0:January - 11:December
204    int m_year; //  1582 -
205    int m_week; // 1 - 53
206
207    Type m_type;
208};
209
210
211} // namespace WebCore
212
213#endif // DateComponents_h
214