muistox/gallery/models/photo.py

import os
from datetime import datetime

from django.db import models
from django.urls import reverse
from imagekit.models import ImageSpecField
from imagekit.processors import ResizeToFit

from gallery.exif import Exif
from gallery.models import Album


class Photo(models.Model):

    def _get_upload_path(instance, filename):
        return os.path.join('albums', str(instance.album.slug), filename)

    def _generate_unique_slug(self, datetime_taken=datetime.now()):
        slug = int(datetime_taken.strftime('%y%m%d%H%M%S'))
        while Photo.objects.filter(album=self.album, slug=slug).exists():
            slug += 1
        return str(slug)

    album = models.ForeignKey(Album, on_delete=models.CASCADE, related_name='photos', verbose_name="Album")
    slug = models.CharField(max_length=15, editable=False, verbose_name="Photo Slug")
    photo = models.ImageField(upload_to=_get_upload_path, height_field='height', width_field='width', verbose_name="Photo")
    photo_sm = ImageSpecField(source='photo', processors=[ResizeToFit(320, 320)], format='JPEG', options={'quality': 70})
    photo_md = ImageSpecField(source='photo', processors=[ResizeToFit(720, 720)], format='JPEG', options={'quality': 80})
    photo_bg = ImageSpecField(source='photo', processors=[ResizeToFit(1920, 1920)], format='JPEG', options={'quality': 90})
    width = models.PositiveIntegerField(default=0, editable=False, verbose_name="Photo Width")
    height = models.PositiveIntegerField(default=0, editable=False, verbose_name="Photo Height")
    taken_at = models.DateTimeField(blank=True, null=True, editable=False, verbose_name="Taken at")
    exif = models.JSONField(blank=True, null=True, editable=False, verbose_name="Exif Metadata")
    is_favorite = models.BooleanField(default=False, verbose_name="Is Favorite")
    views = models.PositiveIntegerField(default=0, verbose_name="Views")
    likes = models.PositiveIntegerField(default=0, verbose_name="Likes")

    @property
    def orientation(self):
        return "Portrait" if self.height > self.width else "Landscape"

    def add_like(self):
        self.likes += 1
        self.save()

    def add_view(self):
        self.views += 1
        self.save()

    def get_next(self):
        return self.__class__.objects.filter(taken_at__gt=self.taken_at, album=self.album.id).order_by('taken_at').first()

    def get_prev(self):
        return self.__class__.objects.filter(taken_at__lt=self.taken_at, album=self.album.id).order_by('-taken_at').first()

    def save(self, *args, **kwargs):
        self.exif_data = Exif(self.photo.path)
        datetime_taken = getattr(self.exif_data, 'datetimeoriginal', datetime.now)()
        self.slug = self.slug or self._generate_unique_slug(datetime_taken)
        self.taken_at = self.taken_at or datetime_taken
        self.exif = getattr(self.exif_data, 'data', None)
        super().save(*args, **kwargs)

    def get_absolute_url(self):
        return reverse('gallery:photo_url', kwargs={'album_slug': self.album.slug, 'photo_slug': self.slug})

    class Meta:
        verbose_name_plural = "Photos"
        ordering = ('-taken_at',)

    def __str__(self):
        return f'{self.slug} ({self.orientation}) {self.is_favorite}'