from pybind11_tests import chrono as m

import datetime

def test_chrono_system_clock():

    # Get the time from both c++ and datetime

    date1 = m.test_chrono1()

    date2 = datetime.datetime.today()

    # The returned value should be a datetime

    assert isinstance(date1, datetime.datetime)

    # The numbers should vary by a very small amount (time it took to execute)

    diff = abs(date1 - date2)

    # There should never be a days/seconds difference

    assert diff.days == 0

    assert diff.seconds == 0

    # We test that no more than about 0.5 seconds passes here

    # This makes sure that the dates created are very close to the same

    # but if the testing system is incredibly overloaded this should still pass

    assert diff.microseconds < 500000

def test_chrono_system_clock_roundtrip():

    date1 = datetime.datetime.today()

    # Roundtrip the time

    date2 = m.test_chrono2(date1)

    # The returned value should be a datetime

    assert isinstance(date2, datetime.datetime)

    # They should be identical (no information lost on roundtrip)

    diff = abs(date1 - date2)

    assert diff.days == 0

    assert diff.seconds == 0

    assert diff.microseconds == 0

def test_chrono_system_clock_roundtrip_date():

    date1 = datetime.date.today()

    # Roundtrip the time

    datetime2 = m.test_chrono2(date1)

    date2 = datetime2.date()

    time2 = datetime2.time()

    # The returned value should be a datetime

    assert isinstance(datetime2, datetime.datetime)

    assert isinstance(date2, datetime.date)

    assert isinstance(time2, datetime.time)

    # They should be identical (no information lost on roundtrip)

    diff = abs(date1 - date2)

    assert diff.days == 0

    assert diff.seconds == 0

    assert diff.microseconds == 0

    # Year, Month & Day should be the same after the round trip

    assert date1.year == date2.year

    assert date1.month == date2.month

    assert date1.day == date2.day

    # There should be no time information

    assert time2.hour == 0

    assert time2.minute == 0

    assert time2.second == 0

    assert time2.microsecond == 0

def test_chrono_system_clock_roundtrip_time():

    time1 = datetime.datetime.today().time()

    # Roundtrip the time

    datetime2 = m.test_chrono2(time1)

    date2 = datetime2.date()

    time2 = datetime2.time()

    # The returned value should be a datetime

    assert isinstance(datetime2, datetime.datetime)

    assert isinstance(date2, datetime.date)

    assert isinstance(time2, datetime.time)

    # Hour, Minute, Second & Microsecond should be the same after the round trip

    assert time1.hour == time2.hour

    assert time1.minute == time2.minute

    assert time1.second == time2.second

    assert time1.microsecond == time2.microsecond

    # There should be no date information (i.e. date = python base date)

    assert date2.year == 1970

    assert date2.month == 1

    assert date2.day == 1

def test_chrono_duration_roundtrip():

    # Get the difference between two times (a timedelta)

    date1 = datetime.datetime.today()

    date2 = datetime.datetime.today()

    diff = date2 - date1

    # Make sure this is a timedelta

    assert isinstance(diff, datetime.timedelta)

    cpp_diff = m.test_chrono3(diff)

    assert cpp_diff.days == diff.days

    assert cpp_diff.seconds == diff.seconds

    assert cpp_diff.microseconds == diff.microseconds

def test_chrono_duration_subtraction_equivalence():

    date1 = datetime.datetime.today()

    date2 = datetime.datetime.today()

    diff = date2 - date1

    cpp_diff = m.test_chrono4(date2, date1)

    assert cpp_diff.days == diff.days

    assert cpp_diff.seconds == diff.seconds

    assert cpp_diff.microseconds == diff.microseconds

def test_chrono_duration_subtraction_equivalence_date():

    date1 = datetime.date.today()

    date2 = datetime.date.today()

    diff = date2 - date1

    cpp_diff = m.test_chrono4(date2, date1)

    assert cpp_diff.days == diff.days

    assert cpp_diff.seconds == diff.seconds

    assert cpp_diff.microseconds == diff.microseconds

def test_chrono_steady_clock():

    time1 = m.test_chrono5()

    assert isinstance(time1, datetime.timedelta)

def test_chrono_steady_clock_roundtrip():

    time1 = datetime.timedelta(days=10, seconds=10, microseconds=100)

    time2 = m.test_chrono6(time1)

    assert isinstance(time2, datetime.timedelta)

    # They should be identical (no information lost on roundtrip)

    assert time1.days == time2.days

    assert time1.seconds == time2.seconds

    assert time1.microseconds == time2.microseconds

def test_floating_point_duration():

    # Test using a floating point number in seconds

    time = m.test_chrono7(35.525123)

    assert isinstance(time, datetime.timedelta)

    assert time.seconds == 35

    assert 525122 <= time.microseconds <= 525123

    diff = m.test_chrono_float_diff(43.789012, 1.123456)

    assert diff.seconds == 42

    assert 665556 <= diff.microseconds <= 665557

def test_nano_timepoint():

    time = datetime.datetime.now()

    time1 = m.test_nano_timepoint(time, datetime.timedelta(seconds=60))

    assert(time1 == time + datetime.timedelta(seconds=60))