import numpy as np
from pytz import UTC

from pandas._libs.tslibs.tzconversion import tz_localize_to_utc

from .tslib import (
    _sizes,
    _tzs,
    tzlocal_obj,
)

try:
    old_sig = False
    from pandas._libs.tslibs import tz_convert_from_utc
except ImportError:
    try:
        old_sig = False
        from pandas._libs.tslibs.tzconversion import tz_convert_from_utc
    except ImportError:
        old_sig = True
        from pandas._libs.tslibs.tzconversion import tz_convert as tz_convert_from_utc


class TimeTZConvert:
    params = [
        _sizes,
        [x for x in _tzs if x is not None],
    ]
    param_names = ["size", "tz"]

    def setup(self, size, tz):
        if size == 10**6 and tz is tzlocal_obj:
            # tzlocal is cumbersomely slow, so skip to keep runtime in check
            raise NotImplementedError

        arr = np.random.randint(0, 10, size=size, dtype="i8")
        self.i8data = arr

    def time_tz_convert_from_utc(self, size, tz):
        # effectively:
        #  dti = DatetimeIndex(self.i8data, tz=tz)
        #  dti.tz_localize(None)
        if old_sig:
            tz_convert_from_utc(self.i8data, UTC, tz)
        else:
            tz_convert_from_utc(self.i8data, tz)

    def time_tz_localize_to_utc(self, size, tz):
        # effectively:
        #  dti = DatetimeIndex(self.i8data)
        #  dti.tz_localize(tz, ambiguous="NaT", nonexistent="NaT")
        tz_localize_to_utc(self.i8data, tz, ambiguous="NaT", nonexistent="NaT")
