# This file is a part of Julia. License is MIT: https://julialang.org/license

# Test conversion to and from unix
@test Dates.unix2datetime(Dates.datetime2unix(DateTime(2000, 1, 1))) == DateTime(2000, 1, 1)
@test Dates.value(Dates.DateTime(1970)) == Dates.UNIXEPOCH

# Tests from here: https://en.wikipedia.org/wiki/Unix_time
@test string(Dates.unix2datetime(1095379198.75)) == string("2004-09-16T23:59:58.75")
@test string(Dates.unix2datetime(1095379199.00)) == string("2004-09-16T23:59:59")
@test string(Dates.unix2datetime(1095379199.25)) == string("2004-09-16T23:59:59.25")
@test string(Dates.unix2datetime(1095379199.50)) == string("2004-09-16T23:59:59.5")
@test string(Dates.unix2datetime(1095379199.75)) == string("2004-09-16T23:59:59.75")
@test string(Dates.unix2datetime(1095379200.00)) == string("2004-09-17T00:00:00")
@test string(Dates.unix2datetime(1095379200.25)) == string("2004-09-17T00:00:00.25")
@test string(Dates.unix2datetime(1095379200.50)) == string("2004-09-17T00:00:00.5")
@test string(Dates.unix2datetime(1095379200.75)) == string("2004-09-17T00:00:00.75")
@test string(Dates.unix2datetime(1095379201.00)) == string("2004-09-17T00:00:01")
@test string(Dates.unix2datetime(1095379201.25)) == string("2004-09-17T00:00:01.25")
@test string(Dates.unix2datetime(915148798.75)) == string("1998-12-31T23:59:58.75")
@test string(Dates.unix2datetime(915148799.00)) == string("1998-12-31T23:59:59")
@test string(Dates.unix2datetime(915148799.25)) == string("1998-12-31T23:59:59.25")
@test string(Dates.unix2datetime(915148799.50)) == string("1998-12-31T23:59:59.5")
@test string(Dates.unix2datetime(915148799.75)) == string("1998-12-31T23:59:59.75")
@test string(Dates.unix2datetime(915148800.00)) == string("1999-01-01T00:00:00")
@test string(Dates.unix2datetime(915148800.25)) == string("1999-01-01T00:00:00.25")
@test string(Dates.unix2datetime(915148800.50)) == string("1999-01-01T00:00:00.5")
@test string(Dates.unix2datetime(915148800.75)) == string("1999-01-01T00:00:00.75")
@test string(Dates.unix2datetime(915148801.00)) == string("1999-01-01T00:00:01")
@test string(Dates.unix2datetime(915148801.25)) == string("1999-01-01T00:00:01.25")

# Test conversion to and from Rata Die
@test Date(Dates.rata2datetime(734869)) == Dates.Date(2013, 1, 1)
@test Dates.datetime2rata(Dates.rata2datetime(734869)) == 734869

# Tests from here: http://mysite.verizon.net/aesir_research/date/back.htm#JDN
@test Dates.julian2datetime(1721119.5) == Dates.DateTime(0, 3, 1)
@test Dates.julian2datetime(1721424.5) == Dates.DateTime(0, 12, 31)
@test Dates.julian2datetime(1721425.5) == Dates.DateTime(1, 1, 1)
@test Dates.julian2datetime(2299149.5) == Dates.DateTime(1582, 10, 4)
@test Dates.julian2datetime(2415020.5) == Dates.DateTime(1900, 1, 1)
@test Dates.julian2datetime(2415385.5) == Dates.DateTime(1901, 1, 1)
@test Dates.julian2datetime(2440587.5) == Dates.DateTime(1970, 1, 1)
@test Dates.julian2datetime(2444239.5) == Dates.DateTime(1980, 1, 1)
@test Dates.julian2datetime(2452695.625) == Dates.DateTime(2003, 2, 25, 3)
@test Dates.datetime2julian(Dates.DateTime(2013, 12, 3, 21)) == 2456630.375

@test typeof(Dates.now()) <: Dates.DateTime
@test typeof(Dates.today()) <: Dates.Date
@test typeof(Dates.now(Dates.UTC)) <: Dates.DateTime

if is_apple()
    withenv("TZ" => "UTC") do
        @test abs(Dates.now() - now(Dates.UTC)) < Dates.Second(1)
    end
end
@test abs(Dates.now() - now(Dates.UTC)) < Dates.Hour(16)

# Issue #9171, #9169
let t = Dates.Period[Dates.Week(2), Dates.Day(14), Dates.Hour(14 * 24), Dates.Minute(14 * 24 * 60), Dates.Second(14 * 24 * 60 * 60), Dates.Millisecond(14 * 24 * 60 * 60 * 1000)]
    for i = 1:length(t)
        Pi = typeof(t[i])
        for j = 1:length(t)
            @test t[i] == t[j]
        end
        for j = i+1:length(t)
            Pj = typeof(t[j])
            tj1 = t[j] + Pj(1)
            @test t[i] < tj1
            @test_throws InexactError Pi(tj1)
            @test_throws InexactError Pj(Pi(typemax(Int64)))
            @test_throws InexactError Pj(Pi(typemin(Int64)))
        end
    end
end
@test Dates.Year(3) == Dates.Month(36)
#@test_throws MethodError Int(Dates.Month(36)) # re-enable when deprecation removed
@test Dates.Year(3) < Dates.Month(37)
@test_throws InexactError convert(Dates.Year, Dates.Month(37))
@test_throws InexactError Dates.Month(Dates.Year(typemax(Int64)))

# Ensure that conversion of 32-bit integers work
let dt = DateTime(1915, 1, 1, 12)
    unix = Int32(Dates.datetime2unix(dt))
    julian = Int32(Dates.datetime2julian(dt))

    @test Dates.unix2datetime(unix) == dt
    @test Dates.julian2datetime(julian) == dt
end

# "Conversions" to/from numbers
a = Dates.DateTime(2000)
b = Dates.Date(2000)
@test Dates.value(b) == 730120
@test Dates.value(a) == 63082368000000
@test convert(Dates.DateTime, Dates.Millisecond(63082368000000)) == a
@test convert(Dates.Millisecond, a) == Dates.Millisecond(63082368000000)
@test Dates.DateTime(Dates.UTM(63082368000000)) == a
@test Dates.DateTime(Dates.UTM(63082368000000.0)) == a
@test convert(Dates.Date, Dates.Day(730120)) == b
@test convert(Dates.Day, b) == Dates.Day(730120)
@test Dates.Date(Dates.UTD(730120)) == b
@test Dates.Date(Dates.UTD(730120.0)) == b
@test Dates.Date(Dates.UTD(Int32(730120))) == b

dt = Dates.DateTime(2000, 1, 1, 23, 59, 59, 50)
t = Dates.Time(dt)
@test Dates.hour(t) == 23
@test Dates.minute(t) == 59
@test Dates.second(t) == 59
@test Dates.millisecond(t) == 50
@test Dates.microsecond(t) == 0
@test Dates.nanosecond(t) == 0