# -*- coding: utf-8 -*-
"""These test the utils.py functions."""

from functools import partial
from typing import Any, Callable, FrozenSet, Union

import pytest
from hypothesis import example, given
from hypothesis.strategies import floats, integers, text
from natsort.compat.fastnumbers import fast_float, fast_int
from natsort.compat.locale import get_strxfrm
from natsort.ns_enum import NSType, NS_DUMB, ns
from natsort.utils import groupletters, string_component_transform_factory

# There are some unicode values that are known failures with the builtin locale
# library on BSD systems that has nothing to do with natsort (a ValueError is
# raised by strxfrm). Let's filter them out.
try:
    bad_uni_chars = frozenset(chr(x) for x in range(0x10FEFD, 0x10FFFF + 1))
except ValueError:
    # Narrow unicode build... no worries.
    bad_uni_chars = frozenset()


def no_bad_uni_chars(x: str, _bad_chars: FrozenSet[str] = bad_uni_chars) -> bool:
    """Ensure text does not contain bad unicode characters"""
    return not any(y in _bad_chars for y in x)


def no_null(x: str) -> bool:
    """Ensure text does not contain a null character."""
    return "\0" not in x


@pytest.mark.parametrize(
    "alg, example_func",
    [
        (ns.INT, fast_int),
        (ns.DEFAULT, fast_int),
        (ns.FLOAT, partial(fast_float, nan=float("-inf"))),
        (ns.FLOAT | ns.NANLAST, partial(fast_float, nan=float("+inf"))),
        (ns.GROUPLETTERS, partial(fast_int, key=groupletters)),
        (ns.LOCALE, partial(fast_int, key=lambda x: get_strxfrm()(x))),
        (
            ns.GROUPLETTERS | ns.LOCALE,
            partial(fast_int, key=lambda x: get_strxfrm()(groupletters(x))),
        ),
        (
            NS_DUMB | ns.LOCALE,
            partial(fast_int, key=lambda x: get_strxfrm()(groupletters(x))),
        ),
        (
            ns.GROUPLETTERS | ns.LOCALE | ns.FLOAT | ns.NANLAST,
            partial(
                fast_float,
                key=lambda x: get_strxfrm()(groupletters(x)),
                nan=float("+inf"),
            ),
        ),
    ],
)
@example(x=float("nan"))
@given(
    x=integers()
    | floats()
    | text().filter(bool).filter(no_bad_uni_chars).filter(no_null)
)
@pytest.mark.usefixtures("with_locale_en_us")
def test_string_component_transform_factory(
    x: Union[str, float, int], alg: NSType, example_func: Callable[[str], Any]
) -> None:
    string_component_transform_func = string_component_transform_factory(alg)
    try:
        assert string_component_transform_func(str(x)) == example_func(str(x))
    except ValueError as e:  # handle broken locale lib on BSD.
        if "is not in range" not in str(e):
            raise
