from django.contrib.auth.models import User
from django.core.exceptions import ValidationError
from django.db import models
from django.urls import reverse
from django.utils import timezone


class GroupedOrder(models.Model):
    name = models.CharField(
        max_length=100, null=True, verbose_name="Titre de la commande"
    )  # optionnal
    orga = models.ForeignKey(
        User, on_delete=models.CASCADE, verbose_name="Organisateur·ice"
    )
    delivery_date = models.DateField("Date de livraison")
    deadline = models.DateTimeField("Date limite de commande")

    def is_ongoing(self):
        """Returns True if the grouped order is open for new Orders - False if it's too late"""
        return self.deadline >= timezone.now()

    def is_to_be_delivered(self):
        """Returns True if the grouped order has not been delivered yet - False if it's old"""
        return self.delivery_date >= timezone.now().date()

    def get_absolute_url(self):
        return reverse("order:manage_items", kwargs={"pk": self.pk})

    def clean_fields(self, exclude=None):
        super().clean_fields(exclude=exclude)
        if self.delivery_date < timezone.now().date():
            raise ValidationError("La date de livraison ne doit pas être dans le passé")

        if self.delivery_date < self.deadline.date():
            raise ValidationError(
                "La date limite de commande doit être avant la date de livraison"
            )

    def __str__(self):  # pragma: no cover
        return (
            self.name
            if self.name
            else f"Commande groupée {self.pk} du {self.date} organisée par {self.orga}"
        )


class Order(models.Model):
    grouped_order = models.ForeignKey(
        GroupedOrder, on_delete=models.CASCADE, related_name="order_set"
    )
    author = models.CharField(
        max_length=100, verbose_name="Personne qui passe la commande"
    )  # a changer, utiliser ForeignKey de user

    def __str__(self):  # pragma: no cover
        return f"Commande de {self.author} pour la commande groupée {self.grouped_order.pk}"


class Item(models.Model):
    name = models.CharField(max_length=100)
    grouped_order = models.ForeignKey(
        GroupedOrder, on_delete=models.CASCADE
    )  # à transformer en manytomany quand il y aura un catalogue
    ordered_nb = models.IntegerField(default=0)

    def get_absolute_url(self):
        return reverse("order:manage_items", kwargs={"pk": self.grouped_order.pk})

    def __str__(self):  # pragma: no cover
        return f"{self.name} dans la commande groupée {self.grouped_order.pk}"


class OrderedItem(models.Model):
    """Item in one specific Order, and its number"""

    nb = models.PositiveSmallIntegerField(default=0)  # works up to 32767
    order = models.ForeignKey(
        Order, on_delete=models.CASCADE, related_name="ordered_items"
    )
    item = models.ForeignKey(Item, on_delete=models.CASCADE, related_name="orders")

    def __str__(self):  # pragma: no cover
        return f"{self.nb} {self.item}, dans la commande {self.order.pk}"