mygpo/core/podcasts.py

   1 from itertools import chain, islice
   2
   3 from mygpo.podcasts.models import Podcast, PodcastGroup
   4 from mygpo.core.proxy import proxy_object
   5 from mygpo.utils import sorted_chain
   6
   7
   8 # the default sort order for podcasts
   9 PODCAST_SORT=lambda p: p.display_title
  10
  11
  12 class PodcastSet(set):
  13     """ Represents a set of podcasts """
  14
  15     def __init__(self, podcasts=None):
  16         self.podcasts = podcasts or []
  17
  18
  19     def get_newest_episodes(self, max_date, num_episodes, max_per_podcast=5):
  20         """ Returns the newest episodes for a set of podcasts """
  21
  22         podcast_key = lambda p: p.latest_episode_timestamp
  23
  24         podcasts = filter(lambda p: p.latest_episode_timestamp, self.podcasts)
  25         podcasts = sorted(podcasts, key=podcast_key, reverse=True)
  26
  27         # we need at most num_episodes podcasts
  28         podcasts = podcasts[:num_episodes]
  29
  30         podcast_dict = dict((p.get_id(), p) for p in podcasts)
  31
  32         # TODO: max_per_podcast
  33         episodes = Episode.objects.filter(podcast__in=podcasts,
  34                                           released__isnull=False,
  35                                           released__lt=max_date,
  36                                          )
  37
  38         for episode in islice(episodes, num_episodes):
  39             p = podcast_dict.get(episode.podcast, None)
  40             yield proxy_object(episode, podcast=p)
  41
  42
  43 def lazy_call(f, *args, **kwargs):
  44     for x in f(*args, **kwargs):
  45         yield x
  46
  47
  48 def individual_podcasts(pg):
  49     """ returns individual podcasts for an iter of Podcast(Group) objects """
  50
  51     for p in pg:
  52         if isinstance(p, Podcast):
  53             yield p
  54
  55         elif isinstance(p, PodcastGroup):
  56             for x in p.podcast_set.all():
  57                 yield x