import datetime

from django.db import models
from django.db.models import BooleanField, CharField, DateField, IntegerField, Q
from markdownx.models import MarkdownxField
from solo.models import SingletonModel


class SiteConfiguration(SingletonModel):
    homepageText = MarkdownxField("Texte de la page d'accueil (Markdown)")
    writearticleText = MarkdownxField("Texte de la page « écrire » (Markdown)")
    email = CharField(
        "Adresse de contact du BOcal", max_length=128, help_text="Attention au spam…"
    )
    specialPublisDescr = MarkdownxField(
        "Texte de la page des " "publications spéciales (Markdown)"
    )

    def __str__(self):
        return "Configuration du site"

    class Meta:  # pyright: ignore
        verbose_name = "Configuration du site"


class Publication(models.Model):
    num = CharField("Numéro du BOcal", max_length=128)
    url = CharField("Adresse sur le site", max_length=512)
    # ^ This is not a URLField because we need internal URLS, eg `/static/blah`

    date = DateField("Publication")
    unknown_date = BooleanField(
        "Date inconnue",
        help_text=(
            "La date de publication du BOcal "
            "est inconnue parce qu'il est "
            "trop vieux. La date indiquée ne "
            "servira qu'à le ranger dans une "
            "année et à ordonner les BOcals."
        ),
        default=False,
    )
    is_special = BooleanField(
        "Numéro spécial", help_text="Numéro du BOcal non-numéroté", default=False
    )
    in_year_view_anyway = BooleanField(
        "Aussi dans l'année",
        help_text=(
            "Si le numéro est spécial, l'afficher quand même dans la "
            "page de l'année correspondante."
        ),
        default=False,
    )
    descr = CharField("Description (optionnelle)", max_length=512, blank=True)
    custom_name = CharField(
        "Nom customisé",
        help_text="Vide pour laisser le numéro seulement",
        max_length=128,
        blank=True,
    )

    class NoPublicationYear(Exception):
        def __str__(self):
            return "No matching publication year."

    @property
    def numericPublicationYear(self):
        startYear = self.date.year
        if self.date.month < 8:
            return startYear - 1
        return startYear

    def publicationYear(self):
        """Fetch corresponding publication year
        Raise `NoPublicationYear` if there is no such entry"""
        startYear = self.numericPublicationYear
        try:
            return PublicationYear.objects.get(startYear=startYear)
        except PublicationYear.DoesNotExist:
            raise self.NoPublicationYear

    def createPubYear(self):
        """Creates the corresponding publication year if needed."""
        if (
            PublicationYear.objects.filter(
                startYear=self.numericPublicationYear
            ).count()
        ) == 0:
            pubYear = PublicationYear(startYear=self.numericPublicationYear, descr="")
            pubYear.save()
            return True
        return False

    def __str__(self):
        if self.custom_name:
            return self.custom_name
        elif self.is_special:
            return self.num
        return "BOcal n°{}".format(self.num)

    @staticmethod
    def latest():
        return Publication.objects.order_by("-date")[0]

    class Meta:
        ordering = ["date"]


class PublicationYear(models.Model):
    startYear = IntegerField(
        "Année de début", help_text="Année scolaire à partir du 15/08", primary_key=True
    )
    descr = MarkdownxField("Accroche de l'année (Markdown)")

    def __str__(self):
        return "{}-{}".format(self.startYear, self.startYear + 1)

    def beg(self):
        """First day of this publication year (incl.)"""
        return datetime.date(self.startYear, 8, 15)

    def end(self):
        """Last day of this publication year (excl.)"""
        return datetime.date(self.startYear + 1, 8, 15)

    def inYear(self, date):
        return self.beg() <= date < self.end()

    def publis(self):
        """List of publications from this year"""
        return Publication.objects.filter(
            Q(is_special=False) | Q(in_year_view_anyway=True),
            date__gte=self.beg(),
            date__lt=self.end(),
        )

    @property
    def url(self):
        return "/{}/".format(self)

    @property
    def prettyName(self):
        return "{} – {}".format(self.startYear, self.startYear + 1)

    class Meta:
        ordering = ["-startYear"]