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

#trunc
dt = Dates.Date(2012, 12, 21)
@test trunc(dt, Dates.Year) == Dates.Date(2012)
@test trunc(dt, Dates.Month) == Dates.Date(2012, 12)
@test trunc(dt, Dates.Day) == Dates.Date(2012, 12, 21)
dt = Dates.DateTime(2012, 12, 21, 16, 30, 20, 200)
@test trunc(dt, Dates.Year) == Dates.DateTime(2012)
@test trunc(dt, Dates.Month) == Dates.DateTime(2012, 12)
@test trunc(dt, Dates.Day) == Dates.DateTime(2012, 12, 21)
@test trunc(dt, Dates.Hour) == Dates.DateTime(2012, 12, 21, 16)
@test trunc(dt, Dates.Minute) == Dates.DateTime(2012, 12, 21, 16, 30)
@test trunc(dt, Dates.Second) == Dates.DateTime(2012, 12, 21, 16, 30, 20)
@test trunc(dt, Dates.Millisecond) == Dates.DateTime(2012, 12, 21, 16, 30, 20, 200)
t = Dates.Time(1, 2, 3, 4, 5, 6)
@test trunc(t, Dates.Hour) == Dates.Time(1)
@test trunc(t, Dates.Minute) == Dates.Time(1, 2)
@test trunc(t, Dates.Second) == Dates.Time(1, 2, 3)
@test trunc(t, Dates.Millisecond) == Dates.Time(1, 2, 3, 4)
@test trunc(t, Dates.Microsecond) == Dates.Time(1, 2, 3, 4, 5)
@test trunc(t, Dates.Nanosecond) == Dates.Time(1, 2, 3, 4, 5, 6)

# Date functions
Jan = Dates.DateTime(2013, 1, 1) #Tuesday
Feb = Dates.DateTime(2013, 2, 2) #Saturday
Mar = Dates.DateTime(2013, 3, 3) #Sunday
Apr = Dates.DateTime(2013, 4, 4) #Thursday
May = Dates.DateTime(2013, 5, 5) #Sunday
Jun = Dates.DateTime(2013, 6, 7) #Friday
Jul = Dates.DateTime(2013, 7, 7) #Sunday
Aug = Dates.DateTime(2013, 8, 8) #Thursday
Sep = Dates.DateTime(2013, 9, 9) #Monday
Oct = Dates.DateTime(2013, 10, 10) #Thursday
Nov = Dates.DateTime(2013, 11, 11) #Monday
Dec = Dates.DateTime(2013, 12, 11) #Wednesday

@test Dates.lastdayofmonth(Jan) == Dates.DateTime(2013, 1, 31)
@test Dates.lastdayofmonth(Feb) == Dates.DateTime(2013, 2, 28)
@test Dates.lastdayofmonth(Mar) == Dates.DateTime(2013, 3, 31)
@test Dates.lastdayofmonth(Apr) == Dates.DateTime(2013, 4, 30)
@test Dates.lastdayofmonth(May) == Dates.DateTime(2013, 5, 31)
@test Dates.lastdayofmonth(Jun) == Dates.DateTime(2013, 6, 30)
@test Dates.lastdayofmonth(Jul) == Dates.DateTime(2013, 7, 31)
@test Dates.lastdayofmonth(Aug) == Dates.DateTime(2013, 8, 31)
@test Dates.lastdayofmonth(Sep) == Dates.DateTime(2013, 9, 30)
@test Dates.lastdayofmonth(Oct) == Dates.DateTime(2013, 10, 31)
@test Dates.lastdayofmonth(Nov) == Dates.DateTime(2013, 11, 30)
@test Dates.lastdayofmonth(Dec) == Dates.DateTime(2013, 12, 31)

@test Dates.lastdayofmonth(Date(Jan)) == Dates.Date(2013, 1, 31)
@test Dates.lastdayofmonth(Date(Feb)) == Dates.Date(2013, 2, 28)
@test Dates.lastdayofmonth(Date(Mar)) == Dates.Date(2013, 3, 31)
@test Dates.lastdayofmonth(Date(Apr)) == Dates.Date(2013, 4, 30)
@test Dates.lastdayofmonth(Date(May)) == Dates.Date(2013, 5, 31)
@test Dates.lastdayofmonth(Date(Jun)) == Dates.Date(2013, 6, 30)
@test Dates.lastdayofmonth(Date(Jul)) == Dates.Date(2013, 7, 31)
@test Dates.lastdayofmonth(Date(Aug)) == Dates.Date(2013, 8, 31)
@test Dates.lastdayofmonth(Date(Sep)) == Dates.Date(2013, 9, 30)
@test Dates.lastdayofmonth(Date(Oct)) == Dates.Date(2013, 10, 31)
@test Dates.lastdayofmonth(Date(Nov)) == Dates.Date(2013, 11, 30)
@test Dates.lastdayofmonth(Date(Dec)) == Dates.Date(2013, 12, 31)

@test Dates.firstdayofmonth(Jan) == Dates.DateTime(2013, 1, 1)
@test Dates.firstdayofmonth(Feb) == Dates.DateTime(2013, 2, 1)
@test Dates.firstdayofmonth(Mar) == Dates.DateTime(2013, 3, 1)
@test Dates.firstdayofmonth(Apr) == Dates.DateTime(2013, 4, 1)
@test Dates.firstdayofmonth(May) == Dates.DateTime(2013, 5, 1)
@test Dates.firstdayofmonth(Jun) == Dates.DateTime(2013, 6, 1)
@test Dates.firstdayofmonth(Jul) == Dates.DateTime(2013, 7, 1)
@test Dates.firstdayofmonth(Aug) == Dates.DateTime(2013, 8, 1)
@test Dates.firstdayofmonth(Sep) == Dates.DateTime(2013, 9, 1)
@test Dates.firstdayofmonth(Oct) == Dates.DateTime(2013, 10, 1)
@test Dates.firstdayofmonth(Nov) == Dates.DateTime(2013, 11, 1)
@test Dates.firstdayofmonth(Dec) == Dates.DateTime(2013, 12, 1)

@test Dates.firstdayofmonth(Date(Jan)) == Dates.Date(2013, 1, 1)
@test Dates.firstdayofmonth(Date(Feb)) == Dates.Date(2013, 2, 1)
@test Dates.firstdayofmonth(Date(Mar)) == Dates.Date(2013, 3, 1)
@test Dates.firstdayofmonth(Date(Apr)) == Dates.Date(2013, 4, 1)
@test Dates.firstdayofmonth(Date(May)) == Dates.Date(2013, 5, 1)
@test Dates.firstdayofmonth(Date(Jun)) == Dates.Date(2013, 6, 1)
@test Dates.firstdayofmonth(Date(Jul)) == Dates.Date(2013, 7, 1)
@test Dates.firstdayofmonth(Date(Aug)) == Dates.Date(2013, 8, 1)
@test Dates.firstdayofmonth(Date(Sep)) == Dates.Date(2013, 9, 1)
@test Dates.firstdayofmonth(Date(Oct)) == Dates.Date(2013, 10, 1)
@test Dates.firstdayofmonth(Date(Nov)) == Dates.Date(2013, 11, 1)
@test Dates.firstdayofmonth(Date(Dec)) == Dates.Date(2013, 12, 1)

# Test first day of week; 2014-01-06 is a Monday = 1st day of week
a = Dates.Date(2014, 1, 6)
b = Dates.Date(2014, 1, 7)
c = Dates.Date(2014, 1, 8)
d = Dates.Date(2014, 1, 9)
e = Dates.Date(2014, 1, 10)
f = Dates.Date(2014, 1, 11)
g = Dates.Date(2014, 1, 12)
@test Dates.firstdayofweek(a) == a
@test Dates.firstdayofweek(b) == a
@test Dates.firstdayofweek(c) == a
@test Dates.firstdayofweek(d) == a
@test Dates.firstdayofweek(e) == a
@test Dates.firstdayofweek(f) == a
@test Dates.firstdayofweek(g) == a
# Test firstdayofweek over the course of the year
dt = a
for i = 0:364
    @test Dates.firstdayofweek(dt) == a + Dates.Week(div(i, 7))
    dt += Dates.Day(1)
end
a = Dates.DateTime(2014, 1, 6)
b = Dates.DateTime(2014, 1, 7)
c = Dates.DateTime(2014, 1, 8)
d = Dates.DateTime(2014, 1, 9)
e = Dates.DateTime(2014, 1, 10)
f = Dates.DateTime(2014, 1, 11)
g = Dates.DateTime(2014, 1, 12)
@test Dates.firstdayofweek(a) == a
@test Dates.firstdayofweek(b) == a
@test Dates.firstdayofweek(c) == a
@test Dates.firstdayofweek(d) == a
@test Dates.firstdayofweek(e) == a
@test Dates.firstdayofweek(f) == a
@test Dates.firstdayofweek(g) == a
dt = a
for i = 0:364
    @test Dates.firstdayofweek(dt) == a + Dates.Week(div(i, 7))
    dt += Dates.Day(1)
end
@test Dates.firstdayofweek(Dates.DateTime(2013, 12, 24)) == Dates.DateTime(2013, 12, 23)
# Test last day of week; Sunday = last day of week
# 2014-01-12 is a Sunday
a = Dates.Date(2014, 1, 6)
b = Dates.Date(2014, 1, 7)
c = Dates.Date(2014, 1, 8)
d = Dates.Date(2014, 1, 9)
e = Dates.Date(2014, 1, 10)
f = Dates.Date(2014, 1, 11)
g = Dates.Date(2014, 1, 12)
@test Dates.lastdayofweek(a) == g
@test Dates.lastdayofweek(b) == g
@test Dates.lastdayofweek(c) == g
@test Dates.lastdayofweek(d) == g
@test Dates.lastdayofweek(e) == g
@test Dates.lastdayofweek(f) == g
@test Dates.lastdayofweek(g) == g
dt = a
for i = 0:364
    @test Dates.lastdayofweek(dt) == g + Dates.Week(div(i, 7))
    dt += Dates.Day(1)
end
a = Dates.DateTime(2014, 1, 6)
b = Dates.DateTime(2014, 1, 7)
c = Dates.DateTime(2014, 1, 8)
d = Dates.DateTime(2014, 1, 9)
e = Dates.DateTime(2014, 1, 10)
f = Dates.DateTime(2014, 1, 11)
g = Dates.DateTime(2014, 1, 12)
@test Dates.lastdayofweek(a) == g
@test Dates.lastdayofweek(b) == g
@test Dates.lastdayofweek(c) == g
@test Dates.lastdayofweek(d) == g
@test Dates.lastdayofweek(e) == g
@test Dates.lastdayofweek(f) == g
@test Dates.lastdayofweek(g) == g
dt = a
for i = 0:364
    @test Dates.lastdayofweek(dt) == g + Dates.Week(div(i, 7))
    dt += Dates.Day(1)
end
@test Dates.lastdayofweek(Dates.DateTime(2013, 12, 24)) == Dates.DateTime(2013, 12, 29)

@test Dates.firstdayofquarter(Dates.Date(2014, 2, 2)) == Dates.Date(2014, 1, 1)
@test Dates.firstdayofquarter(Dates.Date(2014, 5, 2)) == Dates.Date(2014, 4, 1)
@test Dates.firstdayofquarter(Dates.Date(2014, 8, 2)) == Dates.Date(2014, 7, 1)
@test Dates.firstdayofquarter(Dates.Date(2014, 12, 2)) == Dates.Date(2014, 10, 1)

@test Dates.firstdayofquarter(Dates.DateTime(2014, 2, 2)) == Dates.DateTime(2014, 1, 1)
@test Dates.firstdayofquarter(Dates.DateTime(2014, 5, 2)) == Dates.DateTime(2014, 4, 1)
@test Dates.firstdayofquarter(Dates.DateTime(2014, 8, 2)) == Dates.DateTime(2014, 7, 1)
@test Dates.firstdayofquarter(Dates.DateTime(2014, 12, 2)) == Dates.DateTime(2014, 10, 1)

@test Dates.lastdayofquarter(Dates.Date(2014, 2, 2)) == Dates.Date(2014, 3, 31)
@test Dates.lastdayofquarter(Dates.Date(2014, 5, 2)) == Dates.Date(2014, 6, 30)
@test Dates.lastdayofquarter(Dates.Date(2014, 8, 2)) == Dates.Date(2014, 9, 30)
@test Dates.lastdayofquarter(Dates.Date(2014, 12, 2)) == Dates.Date(2014, 12, 31)

@test Dates.lastdayofquarter(Dates.DateTime(2014, 2, 2)) == Dates.DateTime(2014, 3, 31)
@test Dates.lastdayofquarter(Dates.DateTime(2014, 5, 2)) == Dates.DateTime(2014, 6, 30)
@test Dates.lastdayofquarter(Dates.DateTime(2014, 8, 2)) == Dates.DateTime(2014, 9, 30)
@test Dates.lastdayofquarter(Dates.DateTime(2014, 12, 2)) == Dates.DateTime(2014, 12, 31)

firstday = Dates.Date(2014, 1, 1)
lastday = Dates.Date(2014, 12, 31)
for i = 0:364
    dt = firstday + Dates.Day(i)

    @test Dates.firstdayofyear(dt) == firstday
    @test Dates.firstdayofyear(DateTime(dt)) == DateTime(firstday)

    @test Dates.lastdayofyear(dt) == lastday
    @test Dates.lastdayofyear(DateTime(dt)) == DateTime(lastday)
end

# Adjusters
# Adjuster Constructors
@test Dates.Date(Dates.ismonday, 2014) == Dates.Date(2014, 1, 6)
@test Dates.Date(Dates.ismonday, 2014, 5) == Dates.Date(2014, 5, 5)

@test Dates.DateTime(Dates.ismonday, 2014) == Dates.DateTime(2014, 1, 6)
@test Dates.DateTime(Dates.ismonday, 2014, 5) == Dates.DateTime(2014, 5, 5)
@test Dates.DateTime(x->Dates.hour(x)==12, 2014, 5, 21) == Dates.DateTime(2014, 5, 21, 12)
@test Dates.DateTime(x->Dates.minute(x)==30, 2014, 5, 21, 12) == Dates.DateTime(2014, 5, 21, 12, 30)
@test Dates.DateTime(x->Dates.second(x)==30, 2014, 5, 21, 12, 30) == Dates.DateTime(2014, 5, 21, 12, 30, 30)
@test Dates.DateTime(x->Dates.millisecond(x)==500, 2014, 5, 21, 12, 30, 30) == Dates.DateTime(2014, 5, 21, 12, 30, 30, 500)

# tonext, toprev, tofirst, tolast
dt = Dates.Date(2014, 5, 21)
@test Dates.tonext(dt, Dates.Wed) == Dates.Date(2014, 5, 28)
@test Dates.tonext(dt, Dates.Wed; same=true) == dt
@test Dates.tonext(dt, Dates.Thu) == Dates.Date(2014, 5, 22)
@test Dates.tonext(dt, Dates.Fri) == Dates.Date(2014, 5, 23)
@test Dates.tonext(dt, Dates.Sat) == Dates.Date(2014, 5, 24)
@test Dates.tonext(dt, Dates.Sun) == Dates.Date(2014, 5, 25)
@test Dates.tonext(dt, Dates.Mon) == Dates.Date(2014, 5, 26)
@test Dates.tonext(dt, Dates.Tue) == Dates.Date(2014, 5, 27)
# No dayofweek function for out of range values
@test_throws KeyError Dates.tonext(dt, 8)

@test Dates.tonext(Dates.Date(0), Dates.Mon) == Dates.Date(0, 1, 3)

#test func, diff steps, same
@test Dates.tonext(Dates.iswednesday, dt) == Dates.Date(2014, 5, 28)
@test Dates.tonext(Dates.iswednesday, dt; same=true) == dt
@test Dates.tonext(Dates.isthursday, dt) == Dates.Date(2014, 5, 22)
@test Dates.tonext(Dates.isfriday, dt) == Dates.Date(2014, 5, 23)
@test Dates.tonext(Dates.issaturday, dt) == Dates.Date(2014, 5, 24)
@test Dates.tonext(Dates.issunday, dt) == Dates.Date(2014, 5, 25)
@test Dates.tonext(Dates.ismonday, dt) == Dates.Date(2014, 5, 26)
@test Dates.tonext(Dates.istuesday, dt) == Dates.Date(2014, 5, 27)
@test Dates.tonext(Dates.ismonday, Dates.Date(0)) == Dates.Date(0, 1, 3)

@test Dates.tonext(!Dates.iswednesday, dt) == Dates.Date(2014, 5, 22)
@test Dates.tonext(!Dates.isthursday, dt) == Dates.Date(2014, 5, 23)

# Reach adjust limit
@test_throws ArgumentError Dates.tonext(Dates.iswednesday, dt; limit=6)

@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(2)) == Dates.Date(2014, 6, 4)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(3)) == Dates.Date(2014, 6, 11)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(4)) == Dates.Date(2014, 6, 18)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(5)) == Dates.Date(2014, 6, 25)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(6)) == Dates.Date(2014, 7, 2)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Day(7)) == Dates.Date(2014, 5, 28)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(1)) == Dates.Date(2014, 5, 28)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(2)) == Dates.Date(2014, 6, 4)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(3)) == Dates.Date(2014, 6, 11)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(4)) == Dates.Date(2014, 6, 18)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(5)) == Dates.Date(2014, 6, 25)
@test Dates.tonext(Dates.iswednesday, dt;step=Dates.Week(6)) == Dates.Date(2014, 7, 2)

@test Dates.tonext(Dates.iswednesday, dt; same=true) == dt
@test Dates.tonext(Dates.isthursday, dt) == Dates.Date(2014, 5, 22)

#toprev
@test Dates.toprev(dt, Dates.Wed) == Dates.Date(2014, 5, 14)
@test Dates.toprev(dt, Dates.Wed; same=true) == dt
@test Dates.toprev(dt, Dates.Thu) == Dates.Date(2014, 5, 15)
@test Dates.toprev(dt, Dates.Fri) == Dates.Date(2014, 5, 16)
@test Dates.toprev(dt, Dates.Sat) == Dates.Date(2014, 5, 17)
@test Dates.toprev(dt, Dates.Sun) == Dates.Date(2014, 5, 18)
@test Dates.toprev(dt, Dates.Mon) == Dates.Date(2014, 5, 19)
@test Dates.toprev(dt, Dates.Tue) == Dates.Date(2014, 5, 20)
# No dayofweek function for out of range values
@test_throws KeyError Dates.toprev(dt, 8)

@test Dates.toprev(Dates.Date(0), Dates.Mon) == Dates.Date(-1, 12, 27)

#tofirst
@test Dates.tofirst(dt, Dates.Mon) == Dates.Date(2014, 5, 5)
@test Dates.tofirst(dt, Dates.Tue) == Dates.Date(2014, 5, 6)
@test Dates.tofirst(dt, Dates.Wed) == Dates.Date(2014, 5, 7)
@test Dates.tofirst(dt, Dates.Thu) == Dates.Date(2014, 5, 1)
@test Dates.tofirst(dt, Dates.Fri) == Dates.Date(2014, 5, 2)
@test Dates.tofirst(dt, Dates.Sat) == Dates.Date(2014, 5, 3)
@test Dates.tofirst(dt, Dates.Sun) == Dates.Date(2014, 5, 4)

@test Dates.tofirst(dt, Dates.Mon, of=Dates.Year) == Dates.Date(2014, 1, 6)
@test Dates.tofirst(dt, Dates.Tue, of=Dates.Year) == Dates.Date(2014, 1, 7)
@test Dates.tofirst(dt, Dates.Wed, of=Dates.Year) == Dates.Date(2014, 1, 1)
@test Dates.tofirst(dt, Dates.Thu, of=Dates.Year) == Dates.Date(2014, 1, 2)
@test Dates.tofirst(dt, Dates.Fri, of=Dates.Year) == Dates.Date(2014, 1, 3)
@test Dates.tofirst(dt, Dates.Sat, of=Dates.Year) == Dates.Date(2014, 1, 4)
@test Dates.tofirst(dt, Dates.Sun, of=Dates.Year) == Dates.Date(2014, 1, 5)

@test Dates.tofirst(Dates.Date(0), Dates.Mon) == Dates.Date(0, 1, 3)

#tolast
@test Dates.tolast(dt, Dates.Mon) == Dates.Date(2014, 5, 26)
@test Dates.tolast(dt, Dates.Tue) == Dates.Date(2014, 5, 27)
@test Dates.tolast(dt, Dates.Wed) == Dates.Date(2014, 5, 28)
@test Dates.tolast(dt, Dates.Thu) == Dates.Date(2014, 5, 29)
@test Dates.tolast(dt, Dates.Fri) == Dates.Date(2014, 5, 30)
@test Dates.tolast(dt, Dates.Sat) == Dates.Date(2014, 5, 31)
@test Dates.tolast(dt, Dates.Sun) == Dates.Date(2014, 5, 25)

@test Dates.tolast(dt, Dates.Mon, of=Dates.Year) == Dates.Date(2014, 12, 29)
@test Dates.tolast(dt, Dates.Tue, of=Dates.Year) == Dates.Date(2014, 12, 30)
@test Dates.tolast(dt, Dates.Wed, of=Dates.Year) == Dates.Date(2014, 12, 31)
@test Dates.tolast(dt, Dates.Thu, of=Dates.Year) == Dates.Date(2014, 12, 25)
@test Dates.tolast(dt, Dates.Fri, of=Dates.Year) == Dates.Date(2014, 12, 26)
@test Dates.tolast(dt, Dates.Sat, of=Dates.Year) == Dates.Date(2014, 12, 27)
@test Dates.tolast(dt, Dates.Sun, of=Dates.Year) == Dates.Date(2014, 12, 28)

@test Dates.tolast(Dates.Date(0), Dates.Mon) == Dates.Date(0, 1, 31)

# filter (was recur)
startdate = Dates.Date(2014, 1, 1)
stopdate = Dates.Date(2014, 2, 1)
@test length(filter(x->true, startdate:stopdate)) == 32
@test length(filter(x->true, stopdate:Dates.Day(-1):startdate)) == 32

Januarymondays2014 = [Dates.Date(2014, 1, 6), Dates.Date(2014, 1, 13), Dates.Date(2014, 1, 20), Dates.Date(2014, 1, 27)]
@test filter(Dates.ismonday, startdate:stopdate) == Januarymondays2014

@test_throws MethodError filter((x, y)->x + y, Dates.Date(2013):Dates.Date(2014))
@test_throws MethodError Dates.DateFunction((x, y)->x + y, Date(0))
@test_throws ArgumentError Dates.DateFunction((dt)->2, Date(0))
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 2))) == 32
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 1))) == 1
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 2))) == 2
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 3))) == 3
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 4))) == 4
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 5))) == 5
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 6))) == 6
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 7))) == 7
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2013, 1, 8))) == 8
@test length(filter(x->true, Dates.Date(2013):Dates.Month(1):Dates.Date(2013, 1, 1))) == 1
@test length(filter(x->true, Dates.Date(2013):Dates.Day(-1):Dates.Date(2012, 1, 1))) == 367

# Empty range
@test length(filter(x->true, Dates.Date(2013):Dates.Date(2012, 1, 1))) == 0

# All leap days in 20th century
@test length(filter(Dates.Date(1900):Dates.Date(2000)) do x
    Dates.month(x) == Dates.Feb && Dates.day(x) == 29
end) == 24

# Thanksgiving: 4th Thursday of November
thanksgiving = x->Dates.dayofweek(x) == Dates.Thu &&
                      Dates.month(x) == Dates.Nov &&
           Dates.dayofweekofmonth(x) == 4

d = Dates.Date(2014, 6, 5)

@test Dates.tonext(d) do x
    thanksgiving(x)
end == Dates.Date(2014, 11, 27)

@test Dates.toprev(d) do x
    thanksgiving(x)
end == Dates.Date(2013, 11, 28)

# Pittsburgh street cleaning
dr = Dates.Date(2014):Dates.Date(2015)
@test length(filter(dr) do x
    Dates.dayofweek(x) == Dates.Tue &&
    Dates.April < Dates.month(x) < Dates.Nov &&
    Dates.dayofweekofmonth(x) == 2
end) == 6

# U.S. Federal Holidays
newyears(y) = (y, 1, 1)
independenceday(y) = (y, 7, 4)
veteransday(y) = (y, 11, 11)
christmas(y) = (y, 12, 25)

isnewyears(dt) = Dates.yearmonthday(dt) == newyears(Dates.year(dt))
isindependenceday(dt) = Dates.yearmonthday(dt) == independenceday(Dates.year(dt))
isveteransday(dt) = Dates.yearmonthday(dt) == veteransday(Dates.year(dt))
ischristmas(dt) = Dates.yearmonthday(dt) == christmas(Dates.year(dt))
ismartinlutherking(dt) = Dates.dayofweek(dt) == Dates.Mon &&
    Dates.month(dt) == Dates.Jan && Dates.dayofweekofmonth(dt) == 3
ispresidentsday(dt) = Dates.dayofweek(dt) == Dates.Mon &&
    Dates.month(dt) == Dates.Feb && Dates.dayofweekofmonth(dt) == 3
# Last Monday of May
ismemorialday(dt) = Dates.dayofweek(dt) == Dates.Mon &&
                    Dates.month(dt) == Dates.May &&
                    Dates.dayofweekofmonth(dt) == Dates.daysofweekinmonth(dt)
islaborday(dt) = Dates.dayofweek(dt) == Dates.Mon &&
    Dates.month(dt) == Dates.Sep && Dates.dayofweekofmonth(dt) == 1
iscolumbusday(dt) = Dates.dayofweek(dt) == Dates.Mon &&
    Dates.month(dt) == Dates.Oct && Dates.dayofweekofmonth(dt) == 2
isthanksgiving(dt) = Dates.dayofweek(dt) == Dates.Thu &&
    Dates.month(dt) == Dates.Nov && Dates.dayofweekofmonth(dt) == 4

function easter(y)
    # Butcher's Algorithm: http://www.smart.net/~mmontes/butcher.html
    a = y % 19
    b = div(y, 100)
    c = y % 100
    d = div(b, 4)
    e = b % 4
    f = div(b + 8, 25)
    g = div(b - f + 1, 3)
    h = (19 * a + b - d - g + 15) % 30
    i = div(c, 4)
    k = c % 4
    l = (32 + 2 * e + 2 * i - h - k) % 7
    m = div(a + 11 * h + 22 * l, 451)
    month = div(h + l - 7 * m + 114, 31)
    p = (h + l - 7 * m + 114) % 31
    return (y, month, p + 1)
end
iseaster(dt) = Dates.yearmonthday(dt) == easter(Dates.year(dt))

const HOLIDAYS = x->isnewyears(x) || isindependenceday(x) ||
                    isveteransday(x) || ischristmas(x) ||
                    ismartinlutherking(x) || ispresidentsday(x) ||
                    ismemorialday(x) || islaborday(x) ||
                    iscolumbusday(x) || isthanksgiving(x)

@test length(filter(HOLIDAYS, dr)) == 11

const OBSERVEDHOLIDAYS = x->begin
    # If the holiday is on a weekday
    if HOLIDAYS(x) && Dates.dayofweek(x) < Dates.Saturday
        return true
    # Holiday is observed Monday if falls on Sunday
    elseif Dates.dayofweek(x) == 1 && HOLIDAYS(x - Dates.Day(1))
        return true
    # Holiday is observed Friday if falls on Saturday
    elseif Dates.dayofweek(x) == 5 && HOLIDAYS(x + Dates.Day(1))
        return true
    else
        return false
    end
end

observed = filter(OBSERVEDHOLIDAYS, Dates.Date(1999):Dates.Date(2000))
@test length(observed) == 11
@test observed[10] == Dates.Date(1999, 12, 24)
@test observed[11] == Dates.Date(1999, 12, 31)

# Get all business/working days of 2014
# Since we have already defined observed holidays,
# we just look at weekend days and negate the result
@test length(filter(Dates.Date(2014):Dates.Date(2015)) do x
    !(OBSERVEDHOLIDAYS(x) ||
    Dates.dayofweek(x) > 5)
end) == 251

# First day of the next month for each day of 2014
@test length([Dates.firstdayofmonth(i + Dates.Month(1))
    for i in Dates.Date(2014):Dates.Date(2014, 12, 31)]) == 365

# From those goofy email forwards claiming a "special, lucky month"
# that has 5 Fridays, 5 Saturdays, and 5 Sundays and that it only
# occurs every 823 years
@test length(filter(Date(2000):Dates.Month(1):Date(2016)) do dt
    sum = 0
    for i = 1:7
        sum += Dates.dayofweek(dt) > 4 ? Dates.daysofweekinmonth(dt) : 0
        dt += Dates.Day(1)
    end
    return sum == 15
end) == 15 # On average, there's one of those months every year

r = Dates.Time(x->Dates.second(x) == 5, 1)
@test r == Dates.Time(1, 0, 5)

r = filter(x->Dates.second(x) == 5, Dates.Time(0):Dates.Time(10))
@test length(r) == 600
@test first(r) == Dates.Time(0, 0, 5)
@test last(r) == Dates.Time(9, 59, 5)