import unittest
from icalendar.prop import vPeriod
from datetime import datetime, timedelta
import pytest


class TestProp(unittest.TestCase):

    def test_one_day(self):
        # One day in exact datetimes
        per = (datetime(2000, 1, 1), datetime(2000, 1, 2))
        self.assertEqual(vPeriod(per).to_ical(),
                         b'20000101T000000/20000102T000000')

        per = (datetime(2000, 1, 1), timedelta(days=31))
        self.assertEqual(vPeriod(per).to_ical(), b'20000101T000000/P31D')

    def test_roundtrip(self):
        p = vPeriod.from_ical('20000101T000000/20000102T000000')
        self.assertEqual(
            p,
            (datetime(2000, 1, 1, 0, 0), datetime(2000, 1, 2, 0, 0))
        )
        self.assertEqual(vPeriod(p).to_ical(),
                         b'20000101T000000/20000102T000000')

        self.assertEqual(vPeriod.from_ical('20000101T000000/P31D'),
                         (datetime(2000, 1, 1, 0, 0), timedelta(31)))

    def test_round_trip_with_absolute_time(self):
        p = vPeriod.from_ical('20000101T000000Z/20000102T000000Z')
        self.assertEqual(vPeriod(p).to_ical(),
                         b'20000101T000000Z/20000102T000000Z')

    def test_bad_input(self):
        self.assertRaises(ValueError,
                          vPeriod.from_ical, '20000101T000000/Psd31D')


def test_timezoned(tzp):
    start = tzp.localize(datetime(2000, 1, 1), 'Europe/Copenhagen')
    end = tzp.localize(datetime(2000, 1, 2), 'Europe/Copenhagen')
    per = (start, end)
    assert vPeriod(per).to_ical() == b'20000101T000000/20000102T000000'
    assert vPeriod(per).params['TZID'] == 'Europe/Copenhagen'


def test_timezoned_with_timedelta(tzp):
    p = vPeriod((tzp.localize(datetime(2000, 1, 1), 'Europe/Copenhagen'), timedelta(days=31)))
    assert p.to_ical() == b'20000101T000000/P31D'


@pytest.mark.parametrize(
    "params",
    [
        ('20000101T000000', datetime(2000, 1, 2)),
        (datetime(2000, 1, 1), '20000102T000000'),
        (datetime(2000, 1, 2), datetime(2000, 1, 1)),
        (datetime(2000, 1, 2), timedelta(-1)),
    ]
)
def test_invalid_parameters(params):
    """The parameters are of wrong type or of wrong order."""
    with pytest.raises(ValueError):
        vPeriod(params)