1 #ifndef EARTH_TIME_GROUP
2 #define EARTH_TIME_GROUP
8 Copyright (c) 1999-$now By Author. This program is free software; you can
9 redistribute it and/or modify it under the terms of the GNU General Public
10 License as published by the Free Software Foundation; either version 2 of
11 the License or (at your option) any later version. This is online at:
12 http://www.fsf.org/copyleft/gpl.html
13 Please send any updates to: fred@gruntose.com
16 #include <basis/astring.h>
17 #include <basis/byte_array.h>
18 #include <basis/contracts.h>
19 //#include <basis/definitions.h>
20 #include <structures/object_packers.h>
24 //! A set of methods for rendering calendrical and clock times.
26 It is based on the Gregorian calendar currently in use by the USA and other
31 typedef basis::signed_long time_number;
33 enum days { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY };
34 //!< The names of the days of the week.
36 days day_now(); //!< Returns the current local day.
38 const char *day_name(days to_name);
39 //!< Returns the name of the day "to_name".
41 enum months { JANUARY, FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST,
42 SEPTEMBER, OCTOBER, NOVEMBER, DECEMBER };
43 //!< The names of the months in our calendar.
45 months month_now(); //!< returns the local month.
47 const char *month_name(months to_name);
48 //!< Returns the name of the month "to_name".
49 const char *short_month_name(months to_name);
50 //!< Returns a shorter, constant-length (3 characters) month name.
52 extern const time_number days_in_month[12];
53 //!< The number of days in each month in the standard year.
54 extern const time_number leap_days_in_month[12];
55 //!< The number of days in each month in a leap year.
57 extern const time_number julian_days_in_month[12];
58 //!< Number of days in each month based on the julian calendar.
59 extern const time_number julian_leap_days_in_month[12];
60 //!< Number of days in each month of a leap year in the julian calendar.
62 const time_number SECONDS_IN_MINUTE = 60; //!< Number of seconds in one minute.
63 const time_number MINUTES_IN_HOUR = 60; //!< Number of minutes in an hour.
64 const time_number SECONDS_IN_HOUR = 3600; //!< Number of seconds in an hour.
65 const time_number HOURS_IN_DAY = 24; //!< Number of hours in a day.
66 const time_number MINUTES_IN_DAY = 1440; //!< Number of minutes in a day.
67 const time_number SECONDS_IN_DAY = 86400; //!< Number of seconds in a day.
68 const time_number DAYS_IN_YEAR = 365; //!< Number of days in a standard year.
69 const time_number LEAP_DAYS_IN_YEAR = 366; //!< Number of days in a leap year.
70 const double APPROX_DAYS_IN_YEAR = 365.2424;
71 //!< A more accurate measure of the number of days in a year.
72 /*!< This is the more accurate mean length of time in 24 hour days between
73 vernal equinoxes. it's about 11 minutes shy of 365.25 days. */
75 //! An enumeration of time zones, both relative and absolute.
77 LOCAL_ZONE, //!< The time zone this computer is configured to report.
78 GREENWICH_ZONE //!< The time zone of Greenwich Mean Time.
81 // now some structures for representing time...
83 //! A specific point in time as represented by a 24 hour clock.
84 class clock_time : public virtual basis::packable
87 time_number hour; //!< The hour represented in military time: 0 through 23.
88 time_number minute; //!< The number of minutes after the hour.
89 time_number second; //!< The number of seconds after the current minute.
90 time_number millisecond; //!< The number of milliseconds elapsed in this second.
91 time_number microsecond; //!< Number of microseconds elapsed in this millisecond.
93 //! Constructs a clock_time object given all the parts.
94 clock_time(time_number h = 0, time_number m = 0, time_number s = 0, time_number ms = 0, time_number us = 0)
95 : hour(h), minute(m), second(s), millisecond(ms),
99 int packed_size() const { return 5 * structures::PACKED_SIZE_INT32; }
101 virtual void pack(basis::byte_array &packed_form) const;
102 //!< Packs a clock time into an array of bytes.
103 virtual bool unpack(basis::byte_array &packed_form);
104 //!< Unpacks a clock time from an array of bytes.
106 bool operator < (const clock_time &to_compare) const;
107 //!< Returns true if this clock_time is earlier than "to_compare"
108 bool operator == (const clock_time &to_compare) const;
109 //!< Returns true if this clock_time is equal to "to_compare"
111 //! An enumeration of time formatting modes used when printing the time.
113 MERIDIAN = 0x1, //!< default: uses 12 hour with AM/PM and no seconds.
114 MILITARY = 0x2, //!< use military 24 hour time.
115 NO_AM_PM = 0x4, //!< use 12 hour time but don't include AM/PM.
116 SECONDS = 0x8, //!< include the number of seconds as a third field.
117 MILLISECONDS = 0x10 //!< milliseconds are fourth field (after secs).
120 basis::astring text_form(int how = MERIDIAN) const;
121 //!< Prints the clock_time according to "how".
122 /*!< "how" is a combination of time_formats. */
123 void text_form(basis::astring &to_stuff, int how = MERIDIAN) const;
124 //!< Prints the time into "to_stuff" given "how".
125 /*!< note that "to_stuff" will be appended to; the existing contents
128 static time_number normalize(clock_time &to_fix);
129 // ensures that the units in each field are in the proper range by
130 // promoting them upwards. if the clock_time goes above the maximum hour,
131 // then it rolls around. zero is returned for no rollover or a positive
132 // integer is returned for the number of rollovers that occurred. if
133 // there are any negative fields, they are rolled backwards.
134 // the returned rollovers are measured in days.
137 //! An object that represents a particular day in a year.
138 class day_in_year : public virtual basis::packable
141 months month; //!< The current month.
142 time_number day_in_month; //!< The day number within the month (starting at one).
143 days day_of_week; //!< The day of the week.
144 time_number day_of_year; //!< Numerical day, where January 1st is equal to zero.
146 int packed_size() const { return 4 * structures::PACKED_SIZE_INT64; }
148 //! Constructs a representation of the day specified.
149 day_in_year(months m = JANUARY, time_number dim = 1, days dow = SUNDAY,
150 time_number day_o_year = 1) : month(m), day_in_month(dim),
151 day_of_week(dow), day_of_year(day_o_year) {}
153 virtual void pack(basis::byte_array &packed_form) const;
154 //!< Packs a day object into an array of bytes.
155 virtual bool unpack(basis::byte_array &packed_form);
156 //!< Unpacks a day object from an array of bytes.
158 bool operator < (const day_in_year &to_compare) const;
159 //!< Returns true if this day is earlier than "to_compare"
160 /*!< Note that this only compares the month and day in the month. */
161 bool operator == (const day_in_year &to_compare) const;
162 //!< Returns true if this day is equal to "to_compare"
163 /*!< Note that this only compares the month and day in the month. */
165 //! An enumeration of ways to print out the current date.
167 // note: these classes may need to be revised in the year 9999.
168 SHORT_MONTH = 0x1, //!< default: three letter month.
169 LONG_MONTH = 0x2, //!< uses full month name.
170 INCLUDE_DAY = 0x4 //!< adds the name of the day.
173 basis::astring text_form(int how = SHORT_MONTH) const;
174 //!< Prints the day according to "how".
175 void text_form(basis::astring &to_stuff, int how = SHORT_MONTH) const;
176 //!< Prints the day according to "how" and stores it in "to_stuff".
178 static time_number normalize(day_in_year &to_fix, bool leap_year = false);
179 //!< normalizes the day as needed and returns the adjustment in years.
180 /*!< note that this only adjusts the day_in_month and month members
181 currently. the other counters are not changed. */
184 //! An object that represents a particular point in time.
185 /*! It contains both a time of day and the day in the year. */
186 class time_locus : public clock_time, public day_in_year,
187 public virtual basis::hoople_standard
190 time_number year; //!< The year, using the gregorian calendar.
192 time_locus() : clock_time(), day_in_year(), year() {}
194 DEFINE_CLASS_NAME("time_locus");
196 //! Constructs a location in time given its components.
197 time_locus(const clock_time &ct, const day_in_year &ytd, time_number year_in)
198 : clock_time(ct), day_in_year(ytd), year(year_in) {}
200 int packed_size() const { return clock_time::packed_size()
201 + day_in_year::packed_size() + structures::PACKED_SIZE_INT32; }
203 virtual void pack(basis::byte_array &packed_form) const;
204 //!< Packs a time_locus object into an array of bytes.
205 virtual bool unpack(basis::byte_array &packed_form);
206 //!< Unpacks a time_locus object from an array of bytes.
208 // these implement the orderable and equalizable interfaces.
209 virtual bool equal_to(const basis::equalizable &s2) const;
210 virtual bool less_than(const basis::orderable &s2) const;
211 //old bool operator < (const time_locus &to_compare) const;
212 //!< Returns true if this time_locus is earlier than "to_compare"
213 //old bool operator == (const time_locus &to_compare) const;
214 //!< Returns true if this time_locus is equal to "to_compare"
216 //! Enumerates the ways to show the year.
218 LONG_YEAR = 0x1, //!< default: full four digit year (problems in 9999).
219 SHORT_YEAR = 0x2 //!< use only last two digits of year. ugh--Y2K danger.
222 // fulfills obligation for text_formable.
223 virtual void text_form(basis::base_string &state_fill) const {
224 state_fill.assign(text_form_long(clock_time::MERIDIAN, day_in_year::SHORT_MONTH, LONG_YEAR));
227 basis::astring text_form_long(int t = clock_time::MERIDIAN,
228 int d = day_in_year::SHORT_MONTH, int y = LONG_YEAR) const;
229 //! Prints out the time_locus given the way to print each component.
230 /*< "t" is a combination of time_formats, "d" is a combination of
231 date_formats and "y" is a combination of locus_formats. */
232 void text_form_long(basis::astring &to_stuff, int t = clock_time::MERIDIAN,
233 int d = day_in_year::SHORT_MONTH, int y = LONG_YEAR) const;
234 //! Same as text_form() above, but stores into "to_stuff".
236 static time_number normalize(time_locus &to_fix);
237 //!< normalizes the time_locus for its clock time and date.
238 //hmmm: what are rollovers measured in?
241 time_number year_now(); //!< what year is it?
242 clock_time time_now(); //!< what time is it?
243 day_in_year date_now(); //!< what day on the calendar is it?
244 time_locus now(); //!< returns our current locus in the time continuum.
245 time_locus greenwich_now(); //!< returns Greenwich Mean Time (their now).