from django.conf import settings
from django.db import models
from django.utils.text import slugify


class CategoryType(models.TextChoices):
    PRODUCT = 'product', 'Товар'
    SERVICE = 'service', 'Услуга'


class ModerationStatus(models.TextChoices):
    DRAFT = 'draft', 'Черновик'
    PENDING = 'pending', 'На модерации'
    PUBLISHED = 'published', 'Опубликовано'
    REJECTED = 'rejected', 'Отклонено'


class VerificationStatus(models.TextChoices):
    PENDING = 'pending', 'На проверке'
    APPROVED = 'approved', 'Одобрен'
    REVISION = 'revision', 'На доработке'
    REJECTED = 'rejected', 'Отклонён'


class LegalStatus(models.TextChoices):
    SELF_EMPLOYED = 'self_employed', 'Самозанятый'
    IP = 'ip', 'ИП'
    LEGAL_ENTITY = 'legal', 'Юрлицо'


class Category(models.Model):
    """Двухуровневый справочник категорий (ТЗ §3.2)."""

    parent = models.ForeignKey(
        'self', null=True, blank=True, on_delete=models.CASCADE,
        related_name='children', verbose_name='Родитель',
    )
    name = models.CharField('Название', max_length=200)
    slug = models.SlugField('Slug', max_length=220, unique=True, blank=True)
    type = models.CharField(
        'Тип', max_length=10, choices=CategoryType.choices,
        default=CategoryType.PRODUCT,
    )
    sort_order = models.PositiveIntegerField('Порядок сортировки', default=0)

    class Meta:
        verbose_name = 'Категория'
        verbose_name_plural = 'Категории'
        ordering = ('sort_order', 'name')

    def __str__(self):
        return f'{self.parent.name} / {self.name}' if self.parent else self.name

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.name, allow_unicode=True)
        super().save(*args, **kwargs)


class Brand(models.Model):
    """Профиль продавца — «Бренд» (ТЗ §4: Brand / SellerProfile)."""

    user = models.OneToOneField(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE,
        related_name='brand', verbose_name='Владелец',
    )
    name = models.CharField('Название бренда', max_length=200)
    slug = models.SlugField('Slug', max_length=220, unique=True, blank=True)
    logo = models.ImageField('Логотип', upload_to='brands/logos/', blank=True, null=True)
    cover = models.ImageField('Обложка', upload_to='brands/covers/', blank=True, null=True)
    story = models.TextField('История бренда', max_length=3000, blank=True)

    legal_status = models.CharField(
        'Правовой статус', max_length=20,
        choices=LegalStatus.choices, default=LegalStatus.SELF_EMPLOYED,
    )
    inn = models.CharField('ИНН', max_length=12, blank=True)
    region = models.CharField('Регион', max_length=120, blank=True)
    city = models.CharField('Город', max_length=120, blank=True)
    socials = models.JSONField('Соцсети', default=dict, blank=True)

    verification_status = models.CharField(
        'Статус верификации', max_length=20,
        choices=VerificationStatus.choices, default=VerificationStatus.PENDING,
    )
    production_photo = models.ImageField(
        'Фото производства', upload_to='brands/verification/',
        blank=True, null=True,
    )
    statement_doc = models.FileField(
        'Выписка/справка', upload_to='brands/verification/',
        blank=True, null=True,
    )
    badges = models.JSONField('Знаки', default=list, blank=True)
    rating = models.DecimalField('Рейтинг', max_digits=3, decimal_places=2, default=0)

    created_at = models.DateTimeField('Дата создания', auto_now_add=True)

    class Meta:
        verbose_name = 'Бренд'
        verbose_name_plural = 'Бренды'
        ordering = ('name',)

    def __str__(self):
        return self.name

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.name, allow_unicode=True)
        super().save(*args, **kwargs)


class Product(models.Model):
    """Карточка товара (ТЗ §4: Product)."""

    brand = models.ForeignKey(
        Brand, on_delete=models.CASCADE, related_name='products',
        verbose_name='Бренд',
    )
    category = models.ForeignKey(
        Category, on_delete=models.PROTECT, related_name='products',
        verbose_name='Категория',
    )
    name = models.CharField('Название', max_length=255)
    slug = models.SlugField('Slug', max_length=280, unique=True, blank=True)
    description = models.TextField('Описание', blank=True)
    price = models.DecimalField('Цена', max_digits=12, decimal_places=2)
    attributes = models.JSONField('Характеристики', default=dict, blank=True)
    stock = models.PositiveIntegerField('Остаток', default=0)
    lead_time_days = models.PositiveIntegerField('Срок изготовления, дней', default=0)

    moderation_status = models.CharField(
        'Статус модерации', max_length=20,
        choices=ModerationStatus.choices, default=ModerationStatus.DRAFT,
    )
    is_active = models.BooleanField('Активен', default=True)
    created_at = models.DateTimeField('Дата создания', auto_now_add=True)

    class Meta:
        verbose_name = 'Товар'
        verbose_name_plural = 'Товары'
        ordering = ('-created_at',)

    def __str__(self):
        return self.name

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.name, allow_unicode=True)
        super().save(*args, **kwargs)

    @property
    def is_available(self):
        return self.is_active and self.stock > 0


class ProductImage(models.Model):
    """Изображение товара (галерея до 10 фото, ТЗ §3.2)."""

    product = models.ForeignKey(
        Product, on_delete=models.CASCADE, related_name='images',
        verbose_name='Товар',
    )
    image = models.ImageField('Изображение', upload_to='products/')
    sort_order = models.PositiveIntegerField('Порядок', default=0)

    class Meta:
        verbose_name = 'Изображение товара'
        verbose_name_plural = 'Изображения товаров'
        ordering = ('sort_order', 'id')

    def __str__(self):
        return f'Фото #{self.pk} для {self.product}'


class ServiceFormat(models.TextChoices):
    ONLINE = 'online', 'Онлайн'
    OFFLINE = 'offline', 'Офлайн'


class Service(models.Model):
    """Карточка услуги (ТЗ §4: Service)."""

    brand = models.ForeignKey(
        Brand, on_delete=models.CASCADE, related_name='services',
        verbose_name='Бренд',
    )
    category = models.ForeignKey(
        Category, on_delete=models.PROTECT, related_name='services',
        verbose_name='Категория',
    )
    name = models.CharField('Название', max_length=255)
    slug = models.SlugField('Slug', max_length=280, unique=True, blank=True)
    description = models.TextField('Описание', blank=True)
    format = models.CharField(
        'Формат', max_length=10, choices=ServiceFormat.choices,
        default=ServiceFormat.OFFLINE,
    )
    duration_minutes = models.PositiveIntegerField('Длительность, мин', default=60)
    price = models.DecimalField('Цена', max_digits=12, decimal_places=2)

    moderation_status = models.CharField(
        'Статус модерации', max_length=20,
        choices=ModerationStatus.choices, default=ModerationStatus.DRAFT,
    )
    is_active = models.BooleanField('Активна', default=True)
    created_at = models.DateTimeField('Дата создания', auto_now_add=True)

    class Meta:
        verbose_name = 'Услуга'
        verbose_name_plural = 'Услуги'
        ordering = ('-created_at',)

    def __str__(self):
        return self.name

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.name, allow_unicode=True)
        super().save(*args, **kwargs)


class TimeSlot(models.Model):
    """Слот записи на услугу (ТЗ §3.4)."""

    service = models.ForeignKey(
        Service, on_delete=models.CASCADE, related_name='slots',
        verbose_name='Услуга',
    )
    start = models.DateTimeField('Начало')
    end = models.DateTimeField('Окончание')
    is_booked = models.BooleanField('Занят', default=False)

    class Meta:
        verbose_name = 'Слот записи'
        verbose_name_plural = 'Слоты записи'
        ordering = ('start',)

    def __str__(self):
        return f'{self.service} — {self.start:%d.%m.%Y %H:%M}'