translation update
[wolnelektury.git] / src / social / utils.py
1 # -*- coding: utf-8 -*-
2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
4 #
5 from collections import defaultdict
6 from random import randint
7
8 from django.contrib.contenttypes.models import ContentType
9 from django.db.models import Q
10 from django.utils.functional import lazy
11 from catalogue.models import Book, Tag
12 from catalogue import utils
13 from catalogue.tasks import touch_tag
14 from social.models import Cite
15
16
17 def likes(user, work, request=None):
18     if not user.is_authenticated():
19         return False
20
21     if request is None:
22         return work.tags.filter(category='set', user=user).exists()
23
24     if not hasattr(request, 'social_likes'):
25         # tuple: unchecked, checked, liked
26         request.social_likes = defaultdict(lambda: (set(), set(), set()))
27
28     ct = ContentType.objects.get_for_model(type(work))
29     likes_t = request.social_likes[ct.pk]
30     if work.pk in likes_t[1]:
31         return work.pk in likes_t[2]
32     else:
33         likes_t[0].add(work.pk)
34
35         def _likes():
36             if likes_t[0]:
37                 ids = tuple(likes_t[0])
38                 likes_t[0].clear()
39                 likes_t[2].update(Tag.intermediary_table_model.objects.filter(
40                     content_type_id=ct.pk, tag__user_id=user.pk,
41                     object_id__in=ids
42                 ).distinct().values_list('object_id', flat=True))
43                 likes_t[1].update(ids)
44             return work.pk in likes_t[2]
45         return lazy(_likes, bool)()
46
47
48 def get_set(user, name):
49     """Returns a tag for use by the user. Creates it, if necessary."""
50     try:
51         tag = Tag.objects.get(category='set', user=user, name=name)
52     except Tag.DoesNotExist:
53         tag = Tag.objects.create(
54             category='set', user=user, name=name, slug=utils.get_random_hash(name), sort_key=name.lower())
55     return tag
56
57
58 def set_sets(user, work, sets):
59     """Set tags used for given work by a given user."""
60
61     old_sets = list(work.tags.filter(category='set', user=user))
62
63     work.tags = sets + list(
64             work.tags.filter(~Q(category='set') | ~Q(user=user)))
65
66     for shelf in [shelf for shelf in old_sets if shelf not in sets]:
67         touch_tag(shelf)
68     for shelf in [shelf for shelf in sets if shelf not in old_sets]:
69         touch_tag(shelf)
70
71     # delete empty tags
72     Tag.objects.filter(category='set', user=user, items=None).delete()
73
74     if isinstance(work, Book):
75         work.update_popularity()
76
77
78 def cites_for_tags(tags):
79     """Returns a QuerySet with all Cites for books with given tags."""
80     return Cite.objects.filter(book__in=Book.tagged.with_all(tags))
81
82
83 # tag_ids is never used
84 def choose_cite(book_id=None, tag_ids=None):
85     """Choose a cite for main page, for book or for set of tags."""
86     if book_id is not None:
87         cites = Cite.objects.filter(Q(book=book_id) | Q(book__ancestor=book_id))
88     elif tag_ids is not None:
89         tags = Tag.objects.filter(pk__in=tag_ids)
90         cites = cites_for_tags(tags)
91     else:
92         cites = Cite.objects.all()
93     stickies = cites.filter(sticky=True)
94     count = len(stickies)
95     if count:
96         cites = stickies
97     else:
98         count = len(cites)
99     if count:
100         cite = cites[randint(0, count - 1)]
101     else:
102         cite = None
103     return cite
104
105
106 def get_or_choose_cite(request, book_id=None, tag_ids=None):
107     try:
108         assert request.user.is_staff
109         assert 'choose_cite' in request.GET
110         return Cite.objects.get(pk=request.GET['choose_cite'])
111     except (AssertionError, Cite.DoesNotExist):
112         return choose_cite(book_id, tag_ids)