# These are no-regression tests for PR #13572

import numpy as np
import pytest
from numpy.testing import assert_allclose

import astropy.units as u
from astropy.coordinates import earth_orientation
from astropy.time import Time


@pytest.fixture
def tt_to_test():
    return Time("2022-08-25", scale="tt")


@pytest.mark.parametrize(
    "algorithm, result",
    [(2006, 23.43633313804873), (2000, 23.43634457995851), (1980, 23.436346167704045)],
)
def test_obliquity(tt_to_test, algorithm, result):
    assert_allclose(
        earth_orientation.obliquity(tt_to_test.jd, algorithm=algorithm),
        result,
        rtol=1e-13,
    )


def test_precession_matrix_Capitaine(tt_to_test):
    assert_allclose(
        earth_orientation.precession_matrix_Capitaine(
            tt_to_test, tt_to_test + 12.345 * u.yr
        ),
        np.array(
            [
                [9.99995470e-01, -2.76086535e-03, -1.19936388e-03],
                [2.76086537e-03, +9.99996189e-01, -1.64025847e-06],
                [1.19936384e-03, -1.67103117e-06, +9.99999281e-01],
            ]
        ),
        rtol=1e-6,
    )


def test_nutation_components2000B(tt_to_test):
    assert_allclose(
        earth_orientation.nutation_components2000B(tt_to_test.jd),
        (0.4090413775522035, -5.4418953539440996e-05, 3.176996651841667e-05),
        rtol=1e-13,
    )


def test_nutation_matrix(tt_to_test):
    assert_allclose(
        earth_orientation.nutation_matrix(tt_to_test),
        np.array(
            [
                [+9.99999999e-01, +4.99295268e-05, +2.16440489e-05],
                [-4.99288392e-05, +9.99999998e-01, -3.17705068e-05],
                [-2.16456351e-05, +3.17694261e-05, +9.99999999e-01],
            ]
        ),
        rtol=1e-6,
    )