"""Freezes calcul.py's notion of "today" for deterministic tests."""
import datetime as dt_module

import pytest

import calcul


class FrozenDatetime(dt_module.datetime):
    _frozen = dt_module.datetime(2026, 7, 17, 10, 30)  # vendredi

    @classmethod
    def today(cls):
        return cls._frozen

    @classmethod
    def now(cls, tz=None):
        return cls._frozen


@pytest.fixture
def freeze_today(monkeypatch):
    monkeypatch.setattr(calcul, "datetime", FrozenDatetime)
    return FrozenDatetime._frozen