#model Book
class Book(models.Model):


    #book types and placed
    BIOGRAPHY = 1
    FANTASY = 2
    HISTORICAL = 3
    HORROR = 4
    CLASSIC = 5
    YOUTH_LITHERATURE = 6
    NON_FICTION = 7
    MODERN_LITERATURE = 8
    POETRY = 9
    ADVENTURE = 10
    ESSAYS = 11
    ROMANCE = 12
    SATIRE = 13
    THRILLER = 14
    DRAMA = 15
    NONE = 0

    B00K_CHOICES = (
        (BIOGRAPHY,'Biography'),
        (FANTASY, 'Fantasy/Sci-Fi'),
        (HISTORICAL, 'Historical'),
        (HORROR, 'Horror'),
        (CLASSIC, 'Classic'),
        (YOUTH_LITHERATURE, 'Youth Litherature'),
        (NON_FICTION, 'Non-Fiction'),
        (MODERN_LITERATURE, 'Modern Literature'),
        (POETRY, 'Poetry'),
        (ADVENTURE, 'Adventure'),
        (ESSAYS, 'Essays'),
        (ROMANCE, 'Romance'),
        (SATIRE, 'Satire'),
        (THRILLER, 'Thriller'),
        (DRAMA, 'Drama'),
        (NONE, 'No Information'),
    )




    book_image = models.ImageField(upload_to='book_image', blank=True, null=True)
    book_name = models.CharField(max_length=255, unique=True)
    book_author = models.ForeignKey(Author, on_delete=models.CASCADE)
    book_types = models.IntegerField(choices=B00K_CHOICES, default= NONE)
    book_description = models.TextField(null=True, blank=True)
    book_pages = models.PositiveIntegerField(null=True, blank=True)
    book_published = models.DateField(null=True, blank=True)
    book_ratings = GenericRelation(Rating, related_query_name='book', default=NONE)


    def __str__(self):
        return '{}'.format(self.book_name)