from django.db import models
from django.urls import reverse_lazy
from django.contrib.postgres.fields import HStoreField
from django.utils.translation import ugettext_lazy as _

from mptt import (
    models as mptt_models,
    managers as mptt_managers,
    register
)
from mptt.models import MPTTModel, TreeForeignKey
from autoslug import AutoSlugField

from core.models import AbstractStatusModel, AbstractDateTimeModel, STATUS_ACTIVE, STATUS_DELETED


class ProductAttribute(AbstractStatusModel):
    name = models.CharField(max_length=64, blank=True, null=True, default=None)
    slug = AutoSlugField(populate_from='name')
    main_attribute = models.BooleanField(default=False)

    def __str__(self):
        return self.name

    class Meta:
        ordering = ('slug',)
        verbose_name = _('Аттрибут продукта')
        verbose_name_plural = _('Аттрибуты продукта')


class Manufacturer(AbstractStatusModel):
    name = models.CharField(max_length=64, blank=True, null=True, default=None)
    slug = AutoSlugField(populate_from='name')
    image = models.ImageField(upload_to='producers', blank=True, verbose_name="image of producer")

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse_lazy('products:manufacturer', kwargs={'producer_slug': self.slug, 'path': ''})

    # @TODO: tranlsate into english and use traslation
    class Meta:
        verbose_name = _('Производитель')
        verbose_name_plural = _('Производители')


class ProductCategoryManager(mptt_managers.TreeManager):
    def get_root_categories(self):
        return self.get_queryset().all()


class ProductCategory(MPTTModel, AbstractDateTimeModel):
    name = models.CharField(db_index=True, unique=True, max_length=64, blank=True, null=True, default=None)
    slug = AutoSlugField(populate_from='name')
    parent = TreeForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, related_name='children')
    image = models.ImageField(upload_to='categories', blank=True, verbose_name="image of category")

    objects = ProductCategoryManager()

    def __str__(self):
        return self.name

    # @TODO: tranlsate into english and use traslation
    class Meta:
        verbose_name = _("Категория")
        verbose_name_plural = _("Категории")
        ordering = ('tree_id', 'level')

    class MPTTMeta:
        order_insertion_by = ['name']


register(ProductCategory, order_insertion_py=['name'])


class Product(AbstractStatusModel):
    name = models.CharField(max_length=64, db_index=True, blank=True, null=True, default=None)
    slug = AutoSlugField(populate_from='name')
    price = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)
    description = models.TextField(db_index=True, blank=True, null=True, default=None)
    manufacturer = models.ForeignKey(Manufacturer, on_delete=models.PROTECT)
    category = models.ForeignKey(ProductCategory, on_delete=models.SET_NULL, blank=True, null=True, default=None)
    attributes = models.ManyToManyField(ProductAttribute, blank=True)
    discount_policy = HStoreField(blank=True, null=True, default={})
    is_active = models.BooleanField(default=True)

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse_lazy('products:item', args=[self.slug])

    class Meta:
        indexes = [
            models.Index(fields=['id', 'slug'])
        ]
        verbose_name = _('Продукт')
        verbose_name_plural = _('Продукты')



        # def save(self, *args, **kwargs):
        #     if self.category:
        #         super(Product, self).save(*args, **kwargs)
        #
        #         for cp in ProductClass.objects.filter(category=self.product_class):
        #             pp = ProductProperty.objects.filter(category_property=cp,
        #                                                 products=self)
        #             if not pp:
        #                 pp = ProductProperty(category_property=cp, products=self, value="--")
        #                 pp.save()


class ProductAttributeValue(AbstractDateTimeModel):
    product = models.ForeignKey(Product, on_delete=models.PROTECT)
    name = models.CharField(max_length=64, blank=True, null=True, default=None)
    slug = AutoSlugField(populate_from='name')
    attribute = models.ForeignKey(ProductAttribute, on_delete=models.CASCADE, related_name='values')

    def __str__(self):
        return self.name

    class Meta:
        unique_together = ('name', 'attribute')
        verbose_name = 'Product attribute value'
        verbose_name_plural = 'Product attribute values'


# ----------------- PRODUCT IMAGE STATUS LIST ------------------

PRODUCT_IMAGE_STATUS_CHOICES = (
    (STATUS_ACTIVE, _('Активный')),
    (STATUS_DELETED, _('Удален')),
)

PRODUCT_IMAGE_DEFAULT_STATUS = STATUS_ACTIVE


class ProductImage(AbstractStatusModel):
    def get_file_path(self, filename):
        return "products/attachments/{product}/{filename}".format(**{
            'product': self.product.id,
            'filename': filename
        })

    product = models.ForeignKey(Product, on_delete=models.CASCADE)
    status = models.SmallIntegerField(_('Статус'), default=PRODUCT_IMAGE_DEFAULT_STATUS,
                                      choices=PRODUCT_IMAGE_STATUS_CHOICES)
    filename = models.CharField(_('Имя файла'), max_length=255)
    image = models.FileField(_('Изображение'), upload_to=get_file_path, max_length=500)
    is_default = models.BooleanField(_('По умолчанию'), default=False)

    @classmethod
    def create(cls, request, file):
        product_image = cls(request=request, file=file, filename=file.name)
        return product_image

    class Meta:
        verbose_name = _('Изображение продукта')
        verbose_name_plural = _('Изображения продуктов')

# class Offer(models.Model):
#     name = models.CharField(max_length=64, blank=True, null=True, default=None)
#     slug = AutoSlugField(populate_from='name')
#     price = models.DecimalField(max_digits=8, decimal_places=2, null=True, default=0.00)
#     # points = models.DecimalField(max_digits=8, decimal_places=2, null=True, default=0.00)
#     products = models.ForeignKey(Product, on_delete=models.CASCADE, blank=True, null=True, default=None,
#                                 related_name='variants')
#     is_active = models.BooleanField(default=True)
#     attributes = HStoreField(blank=True, null=True, default={})
#
#     def __str__(self):
#         return self.name
#
#     class Meta:
#         verbose_name = 'Offer'
#         verbose_name_plural = 'Offers'
#
#     def save(self, *args, **kwargs):
#         self.points = self.price * decimal.Decimal('0.1')
#         super(Offer, self).save(*args, **kwargs)