import datetime

from django.db import models
from django.utils import timezone
from django.utils.translation import gettext_lazy as _
from rules import is_superuser
from rules.contrib.models import RulesModel


class Season(RulesModel):
    start_date = models.DateField(_("start date"))
    end_date = models.DateField(_("end date"))

    class Meta:
        verbose_name = _("season")
        verbose_name_plural = _("seasons")
        ordering = ["start_date"]
        rules_permissions = {"add": is_superuser, "view": is_superuser, "change": is_superuser, "delete": is_superuser}
        constraints = [
            models.UniqueConstraint(fields=["start_date", "end_date"], name="season_start_date_end_date_unique", violation_error_message=_("Start and end date for a given season must be unique")),
            models.CheckConstraint(condition=models.Q(start_date__lt=models.F("end_date")), name="season_start_date_lt_end_date", violation_error_message=_("Start date must be before end date.")),
        ]

    def __str__(self):
        return _("Season '{start_date} - '{end_date}").format(start_date=self.start_date.strftime("%y"), end_date=self.end_date.strftime("%y"))

    @property
    def is_current(self) -> bool:
        return self.start_date <= timezone.now().date() <= self.end_date

    @property
    def date_range(self) -> tuple[datetime.date, datetime.date]:
        return self.start_date, self.end_date

    @classmethod
    def for_date(cls, current_date: datetime.date | None = None, values_only: bool = False) -> "tuple[datetime.date, datetime.date] | Season":
        if current_date is None:
            current_date = timezone.now().date()

        season = cls.objects.get(start_date__lte=current_date, end_date__gte=current_date)

        if values_only:
            return season.date_range
        return season