mygpo/podcastlists/models.py

   1 from django.db import models
   2 from django.urls import reverse
   3 from django.conf import settings
   4 from django.contrib.contenttypes.models import ContentType
   5 from django.contrib.contenttypes.fields import GenericForeignKey
   6
   7 from mygpo.core.models import UpdateInfoModel, OrderedModel, UUIDModel
   8 from mygpo.podcasts.models import Podcast
   9 from mygpo.votes.models import VoteMixin
  10 from mygpo.utils import set_ordered_entries
  11
  12
  13 class PodcastList(UUIDModel, VoteMixin, UpdateInfoModel):
  14     """ A user-curated collection of podcasts """
  15
  16     # the user that created (and owns) the list
  17     user = models.ForeignKey(settings.AUTH_USER_MODEL,
  18                              on_delete=models.CASCADE)
  19
  20     # the user-assigned title of the list
  21     title = models.CharField(max_length=512)
  22
  23     # the slug (unique for the user) that is derived from the title
  24     slug = models.SlugField(max_length=128)
  25
  26     class Meta:
  27         unique_together = [
  28             # a slug is unique for a user
  29             ('user', 'slug'),
  30         ]
  31
  32     @property
  33     def max_order(self):
  34         return max([-1] + [e.order for e in self.entries.all()])
  35
  36     @property
  37     def num_entries(self):
  38         return self.entries.count()
  39
  40     def add_entry(self, obj):
  41         entry, created = PodcastListEntry.objects.get_or_create(
  42             podcastlist=self,
  43             content_type=ContentType.objects.get_for_model(obj),
  44             object_id=obj.id,
  45             defaults={
  46                 'order': self.max_order + 1,
  47             },
  48         )
  49
  50     def set_entries(self, podcasts):
  51         """ Updates the list to include the given podcast, removes others """
  52
  53         existing = {e.content_object: e for e in self.entries.all()}
  54         set_ordered_entries(self, podcasts, existing, PodcastListEntry,
  55                             'content_object', 'podcastlist')
  56
  57
  58 class PodcastListEntry(UpdateInfoModel, OrderedModel):
  59     """ An entry in a Podcast List """
  60
  61     # the list that the entry belongs to
  62     podcastlist = models.ForeignKey(PodcastList,
  63                                     related_name='entries',
  64                                     on_delete=models.CASCADE,
  65                                    )
  66
  67     # the object (Podcast or PodcastGroup) that is in the list
  68     content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
  69     object_id = models.UUIDField()
  70     content_object = GenericForeignKey('content_type', 'object_id')
  71
  72     class Meta(OrderedModel.Meta):
  73         unique_together = [
  74             ('podcastlist', 'order'),
  75             ('podcastlist', 'content_type', 'object_id'),
  76         ]