-- (c) Copyright - See License.txt

--

--****

-- == Date/Time

--

-- <>

--

namespace datetime

include std/machine.e

include std/dll.e

include std/sequence.e

include std/get.e

include std/error.e

include std/types.e

elsifdef FREEBSD or SUNOS or OPENBSD then

constant gmtime_ = define_c_func(open_dll("libc.so"), "gmtime", {C_POINTER}, C_POINTER)

constant time_ = define_c_func(open_dll("libc.so"), "time", {C_POINTER}, C_INT)

elsifdef OSX then

constant gmtime_ = define_c_func(open_dll("libc.dylib"), "gmtime", {C_POINTER}, C_POINTER)

constant time_ = define_c_func(open_dll("libc.dylib"), "time", {C_POINTER}, C_INT)

elsifdef WIN32 then

constant gmtime_ = define_c_func(open_dll("msvcrt.dll"), "gmtime", {C_POINTER}, C_POINTER)

constant time_ = define_c_proc(open_dll("kernel32.dll"), "GetSystemTimeAsFileTime", {C_POINTER})

end ifdef

atom ptra, valhi, vallow, deltahi, deltalow

deltahi = 27111902

deltalow = 3577643008

ptra = allocate(8)

c_proc(time_, {ptra})

vallow = peek4u(ptra)

valhi = peek4u(ptra+4)

free(ptra)

vallow -= deltalow

valhi -= deltahi

if vallow < 0 then

vallow += power(2, 32)

valhi -= 1

end if

return floor(((valhi * power(2,32)) + vallow) / 10000000)

elsedef

end ifdef

end function

sequence ret

atom timep, tm_p

integer n

end function

constant

-- Helpers ------------------------------------------------------------------

end function

-- Date Handling ------------------------------------------------------------

sequence ly

else

end if

end function

else

end if

end function

end if

end function

-- Functions using the new data-types

integer year, month, day

integer d

end if

end if

end function

integer year

integer j, greg00

365 * year

+ floor(year/4)

+ (greg00 > 0)

* (

- floor(greg00/100)

+ floor(greg00/400+.25)

)

- 11 * (year >= Gregorian_Reformation)

)

end if

end if

end function

integer year, doy

-- Take a guesstimate at the year -- this is usually v.close

else

end if

-- Calculate the day in the guessed year

-- Correct any errors

-- The guesstimate is usually so close that these whiles could probably

-- be made into ifs, but I haven't checked all possible dates yet... ;)

-- guess month

end if

end if

-- Skip to the next year on overflow

-- The alternative is a crash, listed below

end function

-- Conversions to and from seconds

end function

integer days, minutes, hours

end function

--****

-- === Localized Variables

--**

-- Names of the months

"April", "May", "June",

"July", "August", "September",

"October", "November", "December" }

--**

-- Abbreviations of month names

"Apr", "May", "Jun",

"Jul", "Aug", "Sep",

"Oct", "Nov", "Dec" }

--**

-- Names of the days

"Tuesday", "Wednesday",

"Thursday", "Friday",

"Saturday" }

--**

-- Abbreviations of day names

"Tue", "Wed",

"Thu", "Fri",

"Sat" }

--**

-- AM/PM

--****

-- === Constants

--

--**

-- Accessors

-- * ##YEAR##

-- * ##MONTH##

-- * ##DAY##

-- * ##HOUR##

-- * ##MINUTE##

-- * ##SECOND##

--**

-- Intervals

-- * ##YEARS##

-- * ##MONTHS##

-- * ##WEEKS##

-- * ##DAYS##

-- * ##HOURS##

-- * ##MINUTES##

-- * ##SECONDS##

-- * ##DATE##

--****

-- === Types

--**

-- datetime type

--

-- Parameters:

-- # ##obj## : any object, so no crash takes place.

--

-- Comments:

-- A datetime type consists of a sequence of length 6 in the form

-- ##{year, month, day_of_month, hour, minute, second}##. Checks are made to guarantee

-- those values are in range.

--

-- Note:

-- All components must be integers except

-- seconds, as those can also be floating point values.

-- Special case of all zeros is allowed; used when the data is a time only.

end if

end type

--****

-- === Routines

--****

-- Signature:

-- function time()

--

-- Description:

-- Return the number of seconds since some fixed point in the past.

--

-- Returns:

-- An **atom**, which represents an absolute number of seconds.

--

-- Comments:

-- Take the difference between two readings of ##time##(), to measure, for example, how long

-- a section of code takes to execute.

--

-- On some machines, ##time##() can return a negative number. However, you can still use the

-- difference in calls to ##time##() to measure elapsed time.

--

-- Example 1:

--

-- constant ITERATIONS = 1000000

-- integer p

-- atom t0, loop_overhead

--

-- t0 = time()

-- for i = 1 to ITERATIONS do

-- -- time an empty loop

-- end for

-- loop_overhead = time() - t0

--

-- t0 = time()

-- for i = 1 to ITERATIONS do

-- p = power(2, 20)

-- end for

-- ? (time() - t0 - loop_overhead)/ITERATIONS

-- -- calculates time (in seconds) for one call to power

--

--

-- See Also:

-- [[:date]], [[:now]]

--****

-- Signature:

-- function date()

--

-- Description:

-- Return a sequence with information on the current date.

--

-- Returns:

-- A **sequence** of length 8, laid out as follows:

-- # year ~-- since 1900

-- # month ~-- January = 1

-- # day ~-- day of month, starting at 1

-- # hour ~-- 0 to 23

-- # minute ~-- 0 to 59

-- # second ~-- 0 to 59

-- # day of the week ~-- Sunday = 1

-- # day of the year ~-- January 1st = 1

--

-- Comments:

-- The value returned for the year is actually the number of years since 1900 (not the last 2 digits of the year).

-- In the year 2000 this value was 100. In 2001 it was 101, etc.

--

-- Example 1:

--

--

-- now = date()

-- -- now has: {95,3,24,23,47,38,6,83}

-- -- i.e. Friday March 24, 1995 at 11:47:38pm, day 83 of the year

--

--

-- See Also:

-- [[:time]], [[:now]]

--**

-- Convert a sequence formatted according to the built-in ##date##() function to a valid datetime

-- sequence.

--

-- Parameters:

-- # ##src## : a sequence which date() might have returned

--

-- Returns:

-- A **sequence**, more precisely a **datetime** corresponding to the same moment in time.

--

-- Example 1:

--

-- d = from_date(date())

-- -- d is the current date and time

--

--

-- See Also:

-- [[:date]], [[:from_unix]], [[:now]], [[:new]]

end function

--**

-- Create a new datetime value initialized with the current date and time

--

-- Returns:

-- A **sequence**, more precisely a **datetime** corresponding to the current moment in time.

--

-- Example 1:

--

-- dt = now()

-- -- dt is the current date and time

--

--

-- See Also:

-- [[:from_date]], [[:from_unix]], [[:new]], [[:new_time]], [[:now_gmt]]

end function

--**

-- Create a new datetime value that falls into the Greenwich Mean Time (GMT) timezone.

-- This function will return a datetime that is GMT, no matter what timezone the system

-- is running under.

--

-- Example 1:

--

-- dt = now_gmt()

-- -- If local time was July 16th, 2008 at 10:34pm CST

-- -- dt would be July 17th, 2008 at 03:34pm GMT

--

--

-- See Also:

-- [[:now]]

end function

--**

-- Create a new datetime value.

--

-- !! TODO: test default parameter usage

--

-- Parameters:

-- # ##year## ~-- the full year.

-- # ##month## ~-- the month (1-12).

-- # ##day## ~-- the day of the month (1-31).

-- # ##hour## ~-- the hour (0-23) (defaults to 0)

-- # ##minute## ~-- the minute (0-59) (defaults to 0)

-- # ##second## ~-- the second (0-59) (defaults to 0)

--

-- Example 1:

--

-- dt = new(2010, 1, 1, 0, 0, 0)

-- -- dt is Jan 1st, 2010

--

--

-- See Also:

-- [[:from_date]], [[:from_unix]], [[:now]], [[:new_time]]

integer hour=0, integer minute=0, atom second=0)

datetime d

else

end if

end function

--**

-- Create a new datetime value with a date of zeros.

--

-- !! TODO: test

--

-- Parameters:

-- # ##hour## : is the hour (0-23)

-- # ##minute## : is the minute (0-59)

-- # ##second## : is the second (0-59)

--

-- Example 1:

--

-- dt = new_time(10, 30, 55)

-- dt is 10:30:55 AM

--

--

-- See Also:

-- [[:from_date]], [[:from_unix]], [[:now]], [[:new]]

end function

--**

-- Get the day of week of the datetime dt.

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Returns:

-- An **integer**, between 1 (Sunday) and 7 (Saturday).

--

-- Example 1:

--

-- d = new(2008, 5, 2, 0, 0, 0)

-- day = weeks_day(d) -- day is 6 because May 2, 2008 is a Friday.

--

end function

--**

-- Get the Julian day of year of the supplied date.

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Returns:

-- An **integer**, between 1 and 366.

--

-- Comments:

-- For dates earlier than 1800, this routine may give inaccurate results if the date

-- applies to a country other than United Kingdom or a former colony thereof. The change from

-- Julian to Gregorian calendar took place much earlier in some other European countries.

--

-- Example 1:

--

-- d = new(2008, 5, 2, 0, 0, 0)

-- day = years_day(d) -- day is 123

--

end function

--**

-- Determine if ##dt## falls within leap year.

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Returns:

-- An **integer**, of 1 if leap year, otherwise 0.

--

-- Example 1:

--

-- d = new(2008, 1, 1, 0, 0, 0)

-- ? is_leap_year(d) -- prints 1

-- d = new(2005, 1, 1, 0, 0, 0)

-- ? is_leap_year(d) -- prints 0

--

--

-- See Also:

-- [[:days_in_month]]

end function

--**

-- Return the number of days in the month of ##dt##.

--

-- This takes into account leap year.

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Example 1:

--

-- d = new(2008, 1, 1, 0, 0, 0)

-- ? days_in_month(d) -- 31

-- d = new(2008, 2, 1, 0, 0, 0) -- Leap year

-- ? days_in_month(d) -- 29

--

--

-- See Also:

-- [[:is_leap_year]]

end function

--**

-- Return the number of days in the year of ##dt##.

--

-- This takes into account leap year.

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Example 1:

--

-- d = new(2007, 1, 1, 0, 0, 0)

-- ? days_in_year(d) -- 365

-- d = new(2008, 1, 1, 0, 0, 0) -- leap year

-- ? days_in_year(d) -- 366

--

--

-- See Also:

-- [[:is_leap_year]], [[:days_in_month]]

end function

--**

-- Convert a datetime value to the unix numeric format (seconds since ##EPOCH_1970##)

--

-- Parameters:

-- # ##dt## : a datetime to be queried.

--

-- Returns:

-- An **atom**, so this will not overflow during the winter 2038-2039.

--

--

-- Example 1:

--

-- secs_since_epoch = to_unix(now())

-- -- secs_since_epoch is equal to the current seconds since epoch

--

--

-- See Also:

-- [[:from_unix]], [[:format]]

end function

--**

-- Create a datetime value from the unix numeric format (seconds since EPOCH)

--

-- Parameters:

-- # ##unix## : an atom, counting seconds elapsed since EPOCH.

--

-- Returns:

-- A **sequence**, more precisely a **datetime** representing the same moment in time.

--

-- Example 1:

--

-- d = from_unix(0)

-- -- d is 1970-01-01 00:00:00 (zero seconds since EPOCH)

--

--

-- See Also:

-- [[:to_unix]], [[:from_date]], [[:now]], [[:new]]

end function

--**

-- Format the date according to the format pattern string

--

-- Parameters:

-- # ##d## : a datetime which is to be printed out

-- # ##pattern## : a format string, similar to the ones sprintf() uses, but with some Unicode encoding.

-- The default is "%Y-%m-%d %H:%M:%S".

--

-- Returns:

-- A **string**, with the date ##d## formatted according to the specification in ##pattern##.

--

-- Comments:

--

-- Pattern string can include the following specifiers~:

--

-- * ##~%%## ~-- a literal %

-- * ##%a## ~-- locale's abbreviated weekday name (e.g., Sun)

-- * ##%A## ~-- locale's full weekday name (e.g., Sunday)

-- * ##%b## ~-- locale's abbreviated month name (e.g., Jan)

-- * ##%B## ~-- locale's full month name (e.g., January)

-- * ##%C## ~-- century; like %Y, except omit last two digits (e.g., 21)

-- * ##%d## ~-- day of month (e.g, 01)

-- * ##%H## ~-- hour (00..23)

-- * ##%I## ~-- hour (01..12)

-- * ##%j## ~-- day of year (001..366)

-- * ##%k## ~-- hour ( 0..23)

-- * ##%l## ~-- hour ( 1..12)

-- * ##%m## ~-- month (01..12)

-- * ##%M## ~-- minute (00..59)

-- * ##%p## ~-- locale's equivalent of either AM or PM; blank if not known

-- * ##%P## ~-- like %p, but lower case

-- * ##%s## ~-- seconds since 1970-01-01 00:00:00 UTC

-- * ##%S## ~-- second (00..60)

-- * ##%u## ~-- day of week (1..7); 1 is Monday

-- * ##%w## ~-- day of week (0..6); 0 is Sunday

-- * ##%y## ~-- last two digits of year (00..99)

-- * ##%Y## ~-- year

--

-- Example 1:

--

-- d = new(2008, 5, 2, 12, 58, 32)

-- s = format(d, "%Y-%m-%d %H:%M:%S")

-- -- s is "2008-05-02 12:58:32"

--

--

-- Example 2:

--

-- d = new(2008, 5, 2, 12, 58, 32)

-- s = format(d, "%A, %B %d '%y %H:%M%p")

-- -- s is "Friday, May 2 '08 12:58PM"

--

--

-- See Also:

-- [[:to_unix]], [[:parse]]

integer in_fmt, ch, tmp

sequence res

end if

end if

else

end if

else

end if

else

end if

else

-- TODO: error or just add?

end if

else

end if

end function

--**

-- Parse a datetime string according to the given format.

--

-- Parameters:

-- # ##val## : string datetime value

-- # ##fmt## : datetime format. Default is "%Y-%m-%d %H:%M:%S"

--

-- Returns:

-- A **datetime**, value.

--

-- Comments:

-- Only a subset of the format specification is currently supported:

--

-- * ##%d## ~-- day of month (e.g, 01)

-- * ##%H## ~-- hour (00..23)

-- * ##%m## ~-- month (01..12)

-- * ##%M## ~-- minute (00..59)

-- * ##%S## ~-- second (00..60)

-- * ##%Y## ~-- year

--

-- More format codes will be added in future versions.

--

-- All non-format characters in the format string are ignored and are not

-- matched against the input string.

--

-- All non-digits in the input string are ignored.

--

-- Example 1:

--

-- datetime d = parse("05/01/2009 10:20:30", "%m/%d/%Y %H:%M:%S")

--

--

-- See Also:

-- [[:format]]

--

case 'Y' then

case 'm' then

case 'd' then

case 'H' then

case 'M' then

case 'S' then

case else

-- Ignore any invalid format character.

end switch

end if

end if

end if

end if

end if

-- Ensure that what we got could be a date-time value.

end if

-- Ensure no remaining digits in string.

end if

end function

--**

-- Add a number of //intervals// to a datetime.

--

-- Parameters:

-- # ##dt## : the base datetime

-- # ##qty## : the number of //intervals// to add. It should be positive.

-- # ##interval## : which kind of interval to add.

--

-- Returns:

-- A **sequence**, more precisely a **datetime** representing the new moment in time.

--

-- Comments:

-- Please see Constants for Date/Time for a reference of valid intervals.

--

-- Do not confuse the item access constants such as YEAR, MONTH, DAY, etc... with the

-- interval constants YEARS, MONTHS, DAYS, etc...

--

-- When adding MONTHS, it is a calendar based addition. For instance, a date of

-- 5/2/2008 with 5 MONTHS added will become 10/2/2008. MONTHS does not compute the number

-- of days per each month and the average number of days per month.

--

-- When adding YEARS, leap year is taken into account. Adding 4 YEARS to a date may result

-- in a different day of month number due to leap year.

--

-- Example 1:

--

-- d2 = add(d1, 35, SECONDS) -- add 35 seconds to d1

-- d2 = add(d1, 7, WEEKS) -- add 7 weeks to d1

-- d2 = add(d1, 19, YEARS) -- add 19 years to d1

--

--

-- See Also:

-- [[:subtract]], [[:diff]]

integer inc

else

end if

else

end if

end if

end if

end function

--**

-- Subtract a number of //intervals// to a base datetime.

--

-- Parameters:

-- # ##dt## : the base datetime

-- # ##qty## : the number of //intervals// to subtract. It should be positive.

-- # ##interval## : which kind of interval to subtract.

--

-- Returns:

-- A **sequence**, more precisely a **datetime** representing the new moment

-- in time.

--

-- Comments:

-- Please see Constants for Date/Time for a reference of valid intervals.

--

-- See the function ##add##() for more information on adding and subtracting date

-- intervals

--

-- Example 1:

--

-- dt2 = subtract(dt1, 18, MINUTES) -- subtract 18 minutes from dt1

-- dt2 = subtract(dt1, 7, MONTHS) -- subtract 7 months from dt1

-- dt2 = subtract(dt1, 12, HOURS) -- subtract 12 hours from dt1

--

--

-- See Also:

-- [[:add]], [[:diff]]

end function

--**

-- Compute the difference, in seconds, between two dates.

--

-- Parameters:

-- # ##dt1## : the end datetime

-- # ##dt2## : the start datetime

--

-- Returns:

-- An **atom**, the number of seconds elapsed from ##dt2## to ##dt1##.

--

-- Comments:

-- ##dt2## is subtracted from ##dt1##, therefore, you can come up with a negative value.

--

-- Example 1:

--

-- d1 = now()

-- sleep(15) -- sleep for 15 seconds

-- d2 = now()

--

-- i = diff(d1, d2) -- i is 15

--

--

-- See Also:

-- [[:add]], [[:subtract]]

end function