from django.db import models
from django.contrib.auth import get_user_model
from django.contrib.postgres.fields import HStoreField
from django.db.models import Avg
from django.utils.translation import ugettext_lazy as _

from autoslug import AutoSlugField

# Create your models here.
from core.models import AbstractStatusModel, AbstractDateTimeModel
from products.models import Product

OFFER_STATUS_ACTIVE = 25
OFFER_STATUS_INACTIVE = 50

OFFER_STATUS_CHOICES = (
    (OFFER_STATUS_ACTIVE, _('Активный')),
    (OFFER_STATUS_INACTIVE, _('Неактивный'))
)

OFFER_DEFAULT_CHOICE = OFFER_STATUS_INACTIVE


class SupplyType(AbstractDateTimeModel):
    name = models.CharField(max_length=255)
    term = models.ValueRange()


class Offer(AbstractStatusModel):
    product = models.OneToOneField(Product, on_delete=models.CASCADE, primary_key=True)
    price = models.DecimalField(max_digits=8, decimal_places=2, null=True, default=0.00)
    currency = models.CharField(max_length=64, blank=True, null=True, default=None)
    with_nds = models.BooleanField(default=False)
    # attributes = HStoreField(blank=True, null=True, default={})
    suply_type = models.ForeignKey(SupplyType, on_delete=models.SET_NULL, blank=True, null=True)
    note = models.TextField(blank=True, null=True)
    status = models.SmallIntegerField(_('статус'), default=OFFER_DEFAULT_CHOICE, choices=OFFER_STATUS_CHOICES)

    amount = models.IntegerField(blank=True, null=True)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = _('Позиция')
        verbose_name_plural = _('Позиции')


# ------------------------------------------ Buying status --------------------------------------------------- #
BUYING_STATUS_IN_CART = 25
BUYING_STATUS_PENDING = 50
BUYING_STATUS_BOUGHT = 75
BUYING_STATUS_CHOICES = (
    (BUYING_STATUS_IN_CART, _('В корзине')),
    (BUYING_STATUS_PENDING, _('Обрабатываеться')),
    (BUYING_STATUS_BOUGHT, _('Куплен'))
)

BUYING_DEFAULT_CHOICE = BUYING_STATUS_IN_CART


class Buying(AbstractStatusModel):
    user = models.ForeignKey(get_user_model(), verbose_name=_('пользователь'), on_delete=models.CASCADE)
    offer = models.ForeignKey(Offer, verbose_name=_('позиция'), on_delete=models.CASCADE)
    status = models.SmallIntegerField(_('статус'), default=BUYING_DEFAULT_CHOICE, choices=BUYING_STATUS_CHOICES)
    amount = models.SmallIntegerField(_('колличество'), default=0)

    class Meta:
        verbose_name = _('Покупка')
        verbose_name_plural = _('Покупки')


STATUS_GAINED = 0
STATUS_SPENT = 100
CASHBACK_STATUS_CHOICES = (
    (STATUS_GAINED, _('заработанный')),
    (STATUS_SPENT, _('потраченный')),
)

STATUS_DEFAULT = STATUS_GAINED


class CashBackManager(models.Manager):
    def get_gained_cashback_sum(self, user):
        return self.get_queryset().filter(user=user, status=STATUS_GAINED).aggregate(Avg('amount'))

    def get_spent_cashback_sum(self, user):
        return self.get_queryset().filter(user=user, status=STATUS_SPENT).aggregate(Avg('amount'))


class BuyingCashback(AbstractDateTimeModel):
    user = models.ForeignKey(get_user_model(), on_delete=models.CASCADE)
    buying = models.OneToOneField(Buying, on_delete=models.CASCADE)
    amount = models.DecimalField(_('Сумма'), 'cashback', 7, 2, default=0)
    status = models.SmallIntegerField(_('статус'), default=STATUS_DEFAULT, choices=CASHBACK_STATUS_CHOICES)

    objects = CashBackManager()

    class Meta:
        verbose_name_plural = _('cashback')
        verbose_name = _('cashback')