Ad brother episodes for episode view to allow nav

panikdb/emissions/views.py

@@ -122,6 +122,30 @@ class EpisodeDetailView(DetailView):
         context['add_soundfile_form'] = SoundFileForm(initial={'episode': self.object})
         context['add_diffusion_form'] = DiffusionForm(initial={'episode': self.object})
         context['emission'] = Emission.objects.get(slug=self.kwargs.get('emission_slug'))
+        # get all episodes, with an additional attribute to get the date of
+        # their first diffusion
+        context['episodes'] = \
+                Episode.objects.filter(emission=context['emission']
+                    ).extra(select={
+                        'first_diffusion': 'emissions_diffusion.datetime',
+                        },
+                        select_params=(False, True),
+                        where=['''datetime = (SELECT MIN(datetime)
+                                                FROM emissions_diffusion
+                                               WHERE episode_id = emissions_episode.id)'''],
+                        tables=['emissions_diffusion'],
+                    ).order_by('-first_diffusion')
+
+        # get all related soundfiles in a single query
+        soundfiles = {}
+        for soundfile in SoundFile.objects.filter(podcastable=True,
+                fragment=False, episode__emission=self.object):
+            soundfiles[soundfile.episode_id] = soundfile
+
+        # replace dynamic property by a static attribute, to avoid database
+        # lookups
+        for episode in context['episodes']:
+            episode.main_sound = soundfiles.get(episode.id)
         return context