from datetime import datetime
from zoneinfo import ZoneInfo

from timedeltacal import timedeltacal

# Some basic tests. These serve as a specification. All the tests use timezone
# aware datetimes in a timezone with DST, since this is the most complex case.
# Naive datetimes and dates should work analogously.

def test_create_from_datetimes():
    t0 = datetime(2022, 4, 17,  10, 37, 21,  tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 4, 17,  10, 37, 51,  tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    assert d.months == 0
    assert d.days == 0
    assert d.hours == 0
    assert d.minutes == 0
    assert d.seconds == 30
    assert d.microseconds == 0

# Subtract two datetimes - various combinations

def test_sub_same_day():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 4, 17,  13, 12, 17,  789000, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_next_day():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 4, 18,   0, 12, 17,  789000, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_days():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 4, 18,  10, 37, 21,       0, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_days_to_next_month():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 5,  7,  10, 37, 21,       0, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_months():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 5, 17,  10, 37, 21,       0, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_years():
    t0 = datetime(2022, 4, 17,  10, 37, 21,          tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2023, 4, 17,  10, 37, 21,       0, tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2

def test_sub_same_day_dst():
    t0 = datetime(2022, 3, 27,  1, 37, 21,  tzinfo=ZoneInfo("Europe/Vienna"))
    t1 = datetime(2022, 3, 27,  5, 12, 17,  tzinfo=ZoneInfo("Europe/Vienna"))
    d = timedeltacal(t0=t0, t1=t1)
    t2 = t0 + d
    assert t1 == t2