"""
This file tests the behavior of subclasses of Representation and Frames
"""

from copy import deepcopy

import astropy.coordinates
import astropy.units as u
from astropy.coordinates import ICRS, Latitude, Longitude
from astropy.coordinates.baseframe import RepresentationMapping, frame_transform_graph
from astropy.coordinates.representation import (
    REPRESENTATION_CLASSES,
    SphericalRepresentation,
    UnitSphericalRepresentation,
    get_reprdiff_cls_hash,
)
from astropy.coordinates.transformations import FunctionTransform

# Classes setup, borrowed from SunPy.

# Here we define the classes *inside* the tests to make sure that we can wipe
# the slate clean when the tests have finished running.


def setup_function(func):
    func.REPRESENTATION_CLASSES_ORIG = deepcopy(REPRESENTATION_CLASSES)


def teardown_function(func):
    REPRESENTATION_CLASSES.clear()
    REPRESENTATION_CLASSES.update(func.REPRESENTATION_CLASSES_ORIG)
    get_reprdiff_cls_hash.cache_clear()


def test_unit_representation_subclass():
    class Longitude180(Longitude):
        def __new__(cls, angle, unit=None, wrap_angle=180 * u.deg, **kwargs):
            self = super().__new__(
                cls, angle, unit=unit, wrap_angle=wrap_angle, **kwargs
            )
            return self

    class UnitSphericalWrap180Representation(UnitSphericalRepresentation):
        attr_classes = {"lon": Longitude180, "lat": Latitude}

    class SphericalWrap180Representation(SphericalRepresentation):
        attr_classes = {"lon": Longitude180, "lat": Latitude, "distance": u.Quantity}

        _unit_representation = UnitSphericalWrap180Representation

    class MyFrame(ICRS):
        default_representation = SphericalWrap180Representation
        frame_specific_representation_info = {
            "spherical": [
                RepresentationMapping("lon", "ra"),
                RepresentationMapping("lat", "dec"),
            ]
        }
        frame_specific_representation_info[
            "unitsphericalwrap180"
        ] = frame_specific_representation_info["sphericalwrap180"] = (
            frame_specific_representation_info["spherical"]
        )

    @frame_transform_graph.transform(
        FunctionTransform, MyFrame, astropy.coordinates.ICRS
    )
    def myframe_to_icrs(myframe_coo, icrs):
        return icrs.realize_frame(myframe_coo._data)

    f = MyFrame(10 * u.deg, 10 * u.deg)
    assert isinstance(f._data, UnitSphericalWrap180Representation)
    assert isinstance(f.ra, Longitude180)

    g = f.transform_to(astropy.coordinates.ICRS())
    assert isinstance(g, astropy.coordinates.ICRS)
    assert isinstance(g._data, UnitSphericalWrap180Representation)

    frame_transform_graph.remove_transform(MyFrame, astropy.coordinates.ICRS, None)