django-ram/ram/bookshelf/models.py

import os
import shutil
from django.db import models
from django.conf import settings
from django.urls import reverse
from django_countries.fields import CountryField

from tinymce import models as tinymce

from metadata.models import Tag
from ram.utils import DeduplicatedStorage
from ram.models import BaseModel, Image, Document, PropertyInstance
from metadata.models import Scale, Manufacturer


class Publisher(models.Model):
    name = models.CharField(max_length=200)
    country = CountryField(blank=True)
    website = models.URLField(blank=True)

    class Meta:
        ordering = ["name"]

    def __str__(self):
        return self.name


class Author(models.Model):
    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)

    class Meta:
        ordering = ["last_name", "first_name"]

    def __str__(self):
        return f"{self.last_name}, {self.first_name}"

    @property
    def short_name(self):
        return f"{self.last_name} {self.first_name[0]}."


class BaseBook(BaseModel):
    ISBN = models.CharField(max_length=17, blank=True)  # 13 + dashes
    language = models.CharField(
        max_length=7,
        choices=settings.LANGUAGES,
        default='en'
    )
    number_of_pages = models.SmallIntegerField(null=True, blank=True)
    publication_year = models.SmallIntegerField(null=True, blank=True)
    description = tinymce.HTMLField(blank=True)
    price = models.DecimalField(
        max_digits=10,
        decimal_places=2,
        null=True,
        blank=True,
    )
    purchase_date = models.DateField(null=True, blank=True)
    tags = models.ManyToManyField(
        Tag, related_name="bookshelf", blank=True
    )

    def delete(self, *args, **kwargs):
        shutil.rmtree(
            os.path.join(
                settings.MEDIA_ROOT, "images", "books", str(self.uuid)
            ),
            ignore_errors=True
        )
        super(BaseBook, self).delete(*args, **kwargs)


def book_image_upload(instance, filename):
    return os.path.join(
        "images",
        "books",
        str(instance.book.uuid),
        filename
    )


class BaseBookImage(Image):
    book = models.ForeignKey(
        BaseBook, on_delete=models.CASCADE, related_name="image"
    )
    image = models.ImageField(
        upload_to=book_image_upload,
        storage=DeduplicatedStorage,
    )


class BaseBookDocument(Document):
    book = models.ForeignKey(
        BaseBook, on_delete=models.CASCADE, related_name="document"
    )

    class Meta:
        verbose_name_plural = "Documents"
        constraints = [
            models.UniqueConstraint(
                fields=["book", "file"],
                name="unique_book_file"
            )
        ]


class BaseBookProperty(PropertyInstance):
    book = models.ForeignKey(
        BaseBook,
        on_delete=models.CASCADE,
        null=False,
        blank=False,
        related_name="property",
    )


class Book(BaseBook):
    title = models.CharField(max_length=200)
    authors = models.ManyToManyField(Author, blank=True)
    publisher = models.ForeignKey(Publisher, on_delete=models.CASCADE)

    class Meta:
        ordering = ["title"]

    def __str__(self):
        return self.title

    @property
    def publisher_name(self):
        return self.publisher.name

    @property
    def authors_list(self):
        return ", ".join(a.short_name for a in self.authors.all())

    def get_absolute_url(self):
        return reverse(
            "bookshelf_item",
            kwargs={"selector": "book", "uuid": self.uuid}
        )


class Catalog(BaseBook):
    manufacturer = models.ForeignKey(
        Manufacturer,
        on_delete=models.CASCADE,
    )
    years = models.CharField(max_length=12)
    scales = models.ManyToManyField(Scale)

    class Meta:
        ordering = ["manufacturer", "publication_year"]

    def __str__(self):
        scales = self.get_scales()
        return "%s %s %s" % (self.manufacturer.name, self.years, scales)

    def get_absolute_url(self):
        return reverse(
            "bookshelf_item",
            kwargs={"selector": "catalog", "uuid": self.uuid}
        )

    def get_scales(self):
        return "/".join([s.scale for s in self.scales.all()])
    get_scales.short_description = "Scales"