To get from Yokohama to San Francisco, keep going east.
[wolnelektury.git] / src / catalogue / models / book.py
1 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
2 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
3 #
4 from collections import OrderedDict
5 import json
6 from datetime import date, timedelta
7 from random import randint
8 import os.path
9 import re
10 from urllib.request import urlretrieve
11 from django.conf import settings
12 from django.db import connection, models, transaction
13 import django.dispatch
14 from django.contrib.contenttypes.fields import GenericRelation
15 from django.urls import reverse
16 from django.utils.translation import ugettext_lazy as _, get_language
17 from django.utils.deconstruct import deconstructible
18 from fnpdjango.storage import BofhFileSystemStorage
19
20 from librarian.cover import WLCover
21 from librarian.html import transform_abstrakt
22 from newtagging import managers
23 from catalogue import constants
24 from catalogue.fields import EbookField
25 from catalogue.models import Tag, Fragment, BookMedia
26 from catalogue.utils import create_zip, gallery_url, gallery_path, split_tags, get_random_hash
27 from catalogue.models.tag import prefetched_relations
28 from catalogue import app_settings
29 from catalogue import tasks
30 from wolnelektury.utils import makedirs, cached_render, clear_cached_renders
31
32 bofh_storage = BofhFileSystemStorage()
33
34
35 @deconstructible
36 class UploadToPath(object):
37     def __init__(self, path):
38         self.path = path
39
40     def __call__(self, instance, filename):
41         return self.path % instance.slug
42
43
44 _cover_upload_to = UploadToPath('book/cover/%s.jpg')
45 _cover_thumb_upload_to = UploadToPath('book/cover_thumb/%s.jpg')
46 _cover_api_thumb_upload_to = UploadToPath('book/cover_api_thumb/%s.jpg')
47 _simple_cover_upload_to = UploadToPath('book/cover_simple/%s.jpg')
48 _cover_ebookpoint_upload_to = UploadToPath('book/cover_ebookpoint/%s.jpg')
49
50
51 def _ebook_upload_to(upload_path):
52     return UploadToPath(upload_path)
53
54
55 class Book(models.Model):
56     """Represents a book imported from WL-XML."""
57     title = models.CharField(_('title'), max_length=32767)
58     sort_key = models.CharField(_('sort key'), max_length=120, db_index=True, editable=False)
59     sort_key_author = models.CharField(
60         _('sort key by author'), max_length=120, db_index=True, editable=False, default='')
61     slug = models.SlugField(_('slug'), max_length=120, db_index=True, unique=True)
62     common_slug = models.SlugField(_('slug'), max_length=120, db_index=True)
63     language = models.CharField(_('language code'), max_length=3, db_index=True, default=app_settings.DEFAULT_LANGUAGE)
64     description = models.TextField(_('description'), blank=True)
65     abstract = models.TextField(_('abstract'), blank=True)
66     created_at = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
67     changed_at = models.DateTimeField(_('change date'), auto_now=True, db_index=True)
68     parent_number = models.IntegerField(_('parent number'), default=0)
69     extra_info = models.TextField(_('extra information'), default='{}')
70     gazeta_link = models.CharField(blank=True, max_length=240)
71     wiki_link = models.CharField(blank=True, max_length=240)
72     print_on_demand = models.BooleanField(_('print on demand'), default=False)
73     recommended = models.BooleanField(_('recommended'), default=False)
74     audio_length = models.CharField(_('audio length'), blank=True, max_length=8)
75     preview = models.BooleanField(_('preview'), default=False)
76     preview_until = models.DateField(_('preview until'), blank=True, null=True)
77     preview_key = models.CharField(max_length=32, blank=True, null=True)
78     findable = models.BooleanField(_('findable'), default=True, db_index=True)
79
80     # files generated during publication
81     cover = EbookField(
82         'cover', _('cover'),
83         null=True, blank=True,
84         upload_to=_cover_upload_to,
85         storage=bofh_storage, max_length=255)
86     cover_etag = models.CharField(max_length=255, editable=False, default='', db_index=True)
87     # Cleaner version of cover for thumbs
88     cover_thumb = EbookField(
89         'cover_thumb', _('cover thumbnail'),
90         null=True, blank=True,
91         upload_to=_cover_thumb_upload_to,
92         max_length=255)
93     cover_thumb_etag = models.CharField(max_length=255, editable=False, default='', db_index=True)
94     cover_api_thumb = EbookField(
95         'cover_api_thumb', _('cover thumbnail for mobile app'),
96         null=True, blank=True,
97         upload_to=_cover_api_thumb_upload_to,
98         max_length=255)
99     cover_api_thumb_etag = models.CharField(max_length=255, editable=False, default='', db_index=True)
100     simple_cover = EbookField(
101         'simple_cover', _('cover for mobile app'),
102         null=True, blank=True,
103         upload_to=_simple_cover_upload_to,
104         max_length=255)
105     simple_cover_etag = models.CharField(max_length=255, editable=False, default='', db_index=True)
106     cover_ebookpoint = EbookField(
107         'cover_ebookpoint', _('cover for Ebookpoint'),
108         null=True, blank=True,
109         upload_to=_cover_ebookpoint_upload_to,
110         max_length=255)
111     cover_ebookpoint_etag = models.CharField(max_length=255, editable=False, default='', db_index=True)
112     ebook_formats = constants.EBOOK_FORMATS
113     formats = ebook_formats + ['html', 'xml']
114
115     parent = models.ForeignKey('self', models.CASCADE, blank=True, null=True, related_name='children')
116     ancestor = models.ManyToManyField('self', blank=True, editable=False, related_name='descendant', symmetrical=False)
117
118     cached_author = models.CharField(blank=True, max_length=240, db_index=True)
119     has_audience = models.BooleanField(default=False)
120
121     objects = models.Manager()
122     tagged = managers.ModelTaggedItemManager(Tag)
123     tags = managers.TagDescriptor(Tag)
124     tag_relations = GenericRelation(Tag.intermediary_table_model)
125
126     html_built = django.dispatch.Signal()
127     published = django.dispatch.Signal()
128
129     SORT_KEY_SEP = '$'
130
131     class AlreadyExists(Exception):
132         pass
133
134     class Meta:
135         ordering = ('sort_key_author', 'sort_key')
136         verbose_name = _('book')
137         verbose_name_plural = _('books')
138         app_label = 'catalogue'
139
140     def __str__(self):
141         return self.title
142
143     def get_extra_info_json(self):
144         return json.loads(self.extra_info or '{}')
145
146     def get_initial(self):
147         try:
148             return re.search(r'\w', self.title, re.U).group(0)
149         except AttributeError:
150             return ''
151
152     def authors(self):
153         return self.tags.filter(category='author')
154
155     def epochs(self):
156         return self.tags.filter(category='epoch')
157
158     def genres(self):
159         return self.tags.filter(category='genre')
160
161     def kinds(self):
162         return self.tags.filter(category='kind')
163
164     def tag_unicode(self, category):
165         relations = prefetched_relations(self, category)
166         if relations:
167             return ', '.join(rel.tag.name for rel in relations)
168         else:
169             return ', '.join(self.tags.filter(category=category).values_list('name', flat=True))
170
171     def tags_by_category(self):
172         return split_tags(self.tags.exclude(category__in=('set', 'theme')))
173
174     def author_unicode(self):
175         return self.cached_author
176
177     def kind_unicode(self):
178         return self.tag_unicode('kind')
179
180     def epoch_unicode(self):
181         return self.tag_unicode('epoch')
182
183     def genre_unicode(self):
184         return self.tag_unicode('genre')
185
186     def translators(self):
187         translators = self.get_extra_info_json().get('translators') or []
188         return [
189             '\xa0'.join(reversed(translator.split(', ', 1))) for translator in translators
190         ]
191
192     def translator(self):
193         translators = self.get_extra_info_json().get('translators')
194         if not translators:
195             return None
196         if len(translators) > 3:
197             translators = translators[:2]
198             others = ' i inni'
199         else:
200             others = ''
201         return ', '.join('\xa0'.join(reversed(translator.split(', ', 1))) for translator in translators) + others
202
203     def cover_source(self):
204         return self.get_extra_info_json().get('cover_source', self.parent.cover_source() if self.parent else '')
205
206     @property
207     def isbn_pdf(self):
208         return self.get_extra_info_json().get('isbn_pdf')
209
210     @property
211     def isbn_epub(self):
212         return self.get_extra_info_json().get('isbn_epub')
213
214     @property
215     def isbn_mobi(self):
216         return self.get_extra_info_json().get('isbn_mobi')
217
218
219     def save(self, force_insert=False, force_update=False, **kwargs):
220         from sortify import sortify
221
222         self.sort_key = sortify(self.title)[:120]
223         self.title = str(self.title)  # ???
224
225         try:
226             author = self.authors().first().sort_key
227         except AttributeError:
228             author = ''
229         self.sort_key_author = author
230
231         self.cached_author = self.tag_unicode('author')
232         self.has_audience = 'audience' in self.get_extra_info_json()
233
234         if self.preview and not self.preview_key:
235             self.preview_key = get_random_hash(self.slug)[:32]
236
237         ret = super(Book, self).save(force_insert, force_update, **kwargs)
238
239         return ret
240
241     def get_absolute_url(self):
242         return reverse('book_detail', args=[self.slug])
243
244     def gallery_path(self):
245         return gallery_path(self.slug)
246
247     def gallery_url(self):
248         return gallery_url(self.slug)
249
250     def get_first_text(self):
251         if self.html_file:
252             return self
253         child = self.children.all().order_by('parent_number').first()
254         if child is not None:
255             return child.get_first_text()
256
257     def get_last_text(self):
258         if self.html_file:
259             return self
260         child = self.children.all().order_by('parent_number').last()
261         if child is not None:
262             return child.get_last_text()
263
264     def get_prev_text(self):
265         if not self.parent:
266             return None
267         sibling = self.parent.children.filter(parent_number__lt=self.parent_number).order_by('-parent_number').first()
268         if sibling is not None:
269             return sibling.get_last_text()
270         return self.parent.get_prev_text()
271
272     def get_next_text(self):
273         if not self.parent:
274             return None
275         sibling = self.parent.children.filter(parent_number__gt=self.parent_number).order_by('parent_number').first()
276         if sibling is not None:
277             return sibling.get_first_text()
278         return self.parent.get_next_text()
279
280     def get_siblings(self):
281         if not self.parent:
282             return []
283         return self.parent.children.all().order_by('parent_number')
284
285     @property
286     def name(self):
287         return self.title
288
289     def language_code(self):
290         return constants.LANGUAGES_3TO2.get(self.language, self.language)
291
292     def language_name(self):
293         return dict(settings.LANGUAGES).get(self.language_code(), "")
294
295     def is_foreign(self):
296         return self.language_code() != settings.LANGUAGE_CODE
297
298     def set_audio_length(self):
299         length = self.get_audio_length()
300         if length > 0:
301             self.audio_length = self.format_audio_length(length)
302             self.save()
303
304     @staticmethod
305     def format_audio_length(seconds):
306         """
307         >>> Book.format_audio_length(1)
308         '0:01'
309         >>> Book.format_audio_length(3661)
310         '1:01:01'
311         """
312         if seconds < 60*60:
313             minutes = seconds // 60
314             seconds = seconds % 60
315             return '%d:%02d' % (minutes, seconds)
316         else:
317             hours = seconds // 3600
318             minutes = seconds % 3600 // 60
319             seconds = seconds % 60
320             return '%d:%02d:%02d' % (hours, minutes, seconds)
321
322     def get_audio_length(self):
323         total = 0
324         for media in self.get_mp3() or ():
325             total += app_settings.GET_MP3_LENGTH(media.file.path)
326         return int(total)
327
328     def has_media(self, type_):
329         if type_ in Book.formats:
330             return bool(getattr(self, "%s_file" % type_))
331         else:
332             return self.media.filter(type=type_).exists()
333
334     def has_audio(self):
335         return self.has_media('mp3')
336
337     def get_media(self, type_):
338         if self.has_media(type_):
339             if type_ in Book.formats:
340                 return getattr(self, "%s_file" % type_)
341             else:
342                 return self.media.filter(type=type_)
343         else:
344             return None
345
346     def get_mp3(self):
347         return self.get_media("mp3")
348
349     def get_odt(self):
350         return self.get_media("odt")
351
352     def get_ogg(self):
353         return self.get_media("ogg")
354
355     def get_daisy(self):
356         return self.get_media("daisy")
357
358     def media_url(self, format_):
359         media = self.get_media(format_)
360         if media:
361             if self.preview:
362                 return reverse('embargo_link', kwargs={'key': self.preview_key, 'slug': self.slug, 'format_': format_})
363             else:
364                 return media.url
365         else:
366             return None
367
368     def html_url(self):
369         return self.media_url('html')
370
371     def pdf_url(self):
372         return self.media_url('pdf')
373
374     def epub_url(self):
375         return self.media_url('epub')
376
377     def mobi_url(self):
378         return self.media_url('mobi')
379
380     def txt_url(self):
381         return self.media_url('txt')
382
383     def fb2_url(self):
384         return self.media_url('fb2')
385
386     def xml_url(self):
387         return self.media_url('xml')
388
389     def has_description(self):
390         return len(self.description) > 0
391     has_description.short_description = _('description')
392     has_description.boolean = True
393
394     def has_mp3_file(self):
395         return self.has_media("mp3")
396     has_mp3_file.short_description = 'MP3'
397     has_mp3_file.boolean = True
398
399     def has_ogg_file(self):
400         return self.has_media("ogg")
401     has_ogg_file.short_description = 'OGG'
402     has_ogg_file.boolean = True
403
404     def has_daisy_file(self):
405         return self.has_media("daisy")
406     has_daisy_file.short_description = 'DAISY'
407     has_daisy_file.boolean = True
408
409     def get_audiobooks(self):
410         ogg_files = {}
411         for m in self.media.filter(type='ogg').order_by().iterator():
412             ogg_files[m.name] = m
413
414         audiobooks = []
415         projects = set()
416         for mp3 in self.media.filter(type='mp3').iterator():
417             # ogg files are always from the same project
418             meta = mp3.get_extra_info_json()
419             project = meta.get('project')
420             if not project:
421                 # temporary fallback
422                 project = 'CzytamySłuchając'
423
424             projects.add((project, meta.get('funded_by', '')))
425
426             media = {'mp3': mp3}
427
428             ogg = ogg_files.get(mp3.name)
429             if ogg:
430                 media['ogg'] = ogg
431             audiobooks.append(media)
432
433         projects = sorted(projects)
434         return audiobooks, projects
435
436     def wldocument(self, parse_dublincore=True, inherit=True):
437         from catalogue.import_utils import ORMDocProvider
438         from librarian.parser import WLDocument
439
440         if inherit and self.parent:
441             meta_fallbacks = self.parent.cover_info()
442         else:
443             meta_fallbacks = None
444
445         return WLDocument.from_file(
446             self.xml_file.path,
447             provider=ORMDocProvider(self),
448             parse_dublincore=parse_dublincore,
449             meta_fallbacks=meta_fallbacks)
450
451     @staticmethod
452     def zip_format(format_):
453         def pretty_file_name(book):
454             return "%s/%s.%s" % (
455                 book.get_extra_info_json()['author'],
456                 book.slug,
457                 format_)
458
459         field_name = "%s_file" % format_
460         books = Book.objects.filter(parent=None).exclude(**{field_name: ""}).exclude(preview=True).exclude(findable=False)
461         paths = [(pretty_file_name(b), getattr(b, field_name).path) for b in books.iterator()]
462         return create_zip(paths, app_settings.FORMAT_ZIPS[format_])
463
464     def zip_audiobooks(self, format_):
465         bm = BookMedia.objects.filter(book=self, type=format_)
466         paths = map(lambda bm: (None, bm.file.path), bm)
467         return create_zip(paths, "%s_%s" % (self.slug, format_))
468
469     def search_index(self, book_info=None, index=None, index_tags=True, commit=True):
470         if not self.findable:
471             return
472         if index is None:
473             from search.index import Index
474             index = Index()
475         try:
476             index.index_book(self, book_info)
477             if index_tags:
478                 index.index_tags()
479             if commit:
480                 index.index.commit()
481         except Exception as e:
482             index.index.rollback()
483             raise e
484
485     # will make problems in conjunction with paid previews
486     def download_pictures(self, remote_gallery_url):
487         gallery_path = self.gallery_path()
488         # delete previous files, so we don't include old files in ebooks
489         if os.path.isdir(gallery_path):
490             for filename in os.listdir(gallery_path):
491                 file_path = os.path.join(gallery_path, filename)
492                 os.unlink(file_path)
493         ilustr_elements = list(self.wldocument().edoc.findall('//ilustr'))
494         if ilustr_elements:
495             makedirs(gallery_path)
496             for ilustr in ilustr_elements:
497                 ilustr_src = ilustr.get('src')
498                 ilustr_path = os.path.join(gallery_path, ilustr_src)
499                 urlretrieve('%s/%s' % (remote_gallery_url, ilustr_src), ilustr_path)
500
501     def load_abstract(self):
502         abstract = self.wldocument(parse_dublincore=False).edoc.getroot().find('.//abstrakt')
503         if abstract is not None:
504             self.abstract = transform_abstrakt(abstract)
505         else:
506             self.abstract = ''
507
508     @classmethod
509     def from_xml_file(cls, xml_file, **kwargs):
510         from django.core.files import File
511         from librarian import dcparser
512
513         # use librarian to parse meta-data
514         book_info = dcparser.parse(xml_file)
515
516         if not isinstance(xml_file, File):
517             xml_file = File(open(xml_file))
518
519         try:
520             return cls.from_text_and_meta(xml_file, book_info, **kwargs)
521         finally:
522             xml_file.close()
523
524     @classmethod
525     def from_text_and_meta(cls, raw_file, book_info, overwrite=False, dont_build=None, search_index=True,
526                            search_index_tags=True, remote_gallery_url=None, days=0, findable=True):
527         if dont_build is None:
528             dont_build = set()
529         dont_build = set.union(set(dont_build), set(app_settings.DONT_BUILD))
530
531         # check for parts before we do anything
532         children = []
533         if hasattr(book_info, 'parts'):
534             for part_url in book_info.parts:
535                 try:
536                     children.append(Book.objects.get(slug=part_url.slug))
537                 except Book.DoesNotExist:
538                     raise Book.DoesNotExist(_('Book "%s" does not exist.') % part_url.slug)
539
540         # Read book metadata
541         book_slug = book_info.url.slug
542         if re.search(r'[^a-z0-9-]', book_slug):
543             raise ValueError('Invalid characters in slug')
544         book, created = Book.objects.get_or_create(slug=book_slug)
545
546         if created:
547             book_shelves = []
548             old_cover = None
549             book.preview = bool(days)
550             if book.preview:
551                 book.preview_until = date.today() + timedelta(days)
552         else:
553             if not overwrite:
554                 raise Book.AlreadyExists(_('Book %s already exists') % book_slug)
555             # Save shelves for this book
556             book_shelves = list(book.tags.filter(category='set'))
557             old_cover = book.cover_info()
558
559         # Save XML file
560         book.xml_file.save('%s.xml' % book.slug, raw_file, save=False)
561         if book.preview:
562             book.xml_file.set_readable(False)
563
564         book.findable = findable
565         book.language = book_info.language
566         book.title = book_info.title
567         if book_info.variant_of:
568             book.common_slug = book_info.variant_of.slug
569         else:
570             book.common_slug = book.slug
571         book.extra_info = json.dumps(book_info.to_dict())
572         book.load_abstract()
573         book.save()
574
575         meta_tags = Tag.tags_from_info(book_info)
576
577         for tag in meta_tags:
578             if not tag.for_books:
579                 tag.for_books = True
580                 tag.save()
581
582         book.tags = set(meta_tags + book_shelves)
583         book.save()  # update sort_key_author
584
585         cover_changed = old_cover != book.cover_info()
586         obsolete_children = set(b for b in book.children.all()
587                                 if b not in children)
588         notify_cover_changed = []
589         for n, child_book in enumerate(children):
590             new_child = child_book.parent != book
591             child_book.parent = book
592             child_book.parent_number = n
593             child_book.save()
594             if new_child or cover_changed:
595                 notify_cover_changed.append(child_book)
596         # Disown unfaithful children and let them cope on their own.
597         for child in obsolete_children:
598             child.parent = None
599             child.parent_number = 0
600             child.save()
601             if old_cover:
602                 notify_cover_changed.append(child)
603
604         cls.repopulate_ancestors()
605         tasks.update_counters.delay()
606
607         if remote_gallery_url:
608             book.download_pictures(remote_gallery_url)
609
610         # No saves beyond this point.
611
612         # Build cover.
613         if 'cover' not in dont_build:
614             book.cover.build_delay()
615             book.cover_thumb.build_delay()
616             book.cover_api_thumb.build_delay()
617             book.simple_cover.build_delay()
618             book.cover_ebookpoint.build_delay()
619
620         # Build HTML and ebooks.
621         book.html_file.build_delay()
622         if not children:
623             for format_ in constants.EBOOK_FORMATS_WITHOUT_CHILDREN:
624                 if format_ not in dont_build:
625                     getattr(book, '%s_file' % format_).build_delay()
626         for format_ in constants.EBOOK_FORMATS_WITH_CHILDREN:
627             if format_ not in dont_build:
628                 getattr(book, '%s_file' % format_).build_delay()
629
630         if not settings.NO_SEARCH_INDEX and search_index and findable:
631             tasks.index_book.delay(book.id, book_info=book_info, index_tags=search_index_tags)
632
633         for child in notify_cover_changed:
634             child.parent_cover_changed()
635
636         book.update_popularity()
637         tasks.update_references.delay(book.id)
638
639         cls.published.send(sender=cls, instance=book)
640         return book
641
642     def get_master(self):
643         master_tags = [
644             'opowiadanie',
645             'powiesc',
646             'dramat_wierszowany_l',
647             'dramat_wierszowany_lp',
648             'dramat_wspolczesny', 'liryka_l', 'liryka_lp',
649             'wywiad',
650         ]
651         from librarian.parser import WLDocument
652         wld = WLDocument.from_file(self.xml_file.path, parse_dublincore=False)
653         root = wld.edoc.getroot()
654         for master in root.iter():
655             if master.tag in master_tags:
656                 return master
657     
658     def update_references(self):
659         from references.models import Entity, Reference
660         master = self.get_master()
661         found = set()
662         for i, sec in enumerate(master):
663             for ref in sec.findall('.//ref'):
664                 href = ref.attrib.get('href', '')
665                 if not href or href in found:
666                     continue
667                 found.add(href)
668                 entity, created = Entity.objects.get_or_create(
669                     uri=href
670                 )
671                 ref, created = Reference.objects.get_or_create(
672                     book=self,
673                     entity=entity
674                 )
675                 ref.first_section = 'sec%d' % (i + 1)
676                 entity.populate()
677                 entity.save()
678         Reference.objects.filter(book=self).exclude(entity__uri__in=found).delete()
679     
680     @property
681     def references(self):
682         return self.reference_set.all().select_related('entity')
683
684     @classmethod
685     @transaction.atomic
686     def repopulate_ancestors(cls):
687         """Fixes the ancestry cache."""
688         # TODO: table names
689         cursor = connection.cursor()
690         if connection.vendor == 'postgres':
691             cursor.execute("TRUNCATE catalogue_book_ancestor")
692             cursor.execute("""
693                 WITH RECURSIVE ancestry AS (
694                     SELECT book.id, book.parent_id
695                     FROM catalogue_book AS book
696                     WHERE book.parent_id IS NOT NULL
697                     UNION
698                     SELECT ancestor.id, book.parent_id
699                     FROM ancestry AS ancestor, catalogue_book AS book
700                     WHERE ancestor.parent_id = book.id
701                         AND book.parent_id IS NOT NULL
702                     )
703                 INSERT INTO catalogue_book_ancestor
704                     (from_book_id, to_book_id)
705                     SELECT id, parent_id
706                     FROM ancestry
707                     ORDER BY id;
708                 """)
709         else:
710             cursor.execute("DELETE FROM catalogue_book_ancestor")
711             for b in cls.objects.exclude(parent=None):
712                 parent = b.parent
713                 while parent is not None:
714                     b.ancestor.add(parent)
715                     parent = parent.parent
716
717     def clear_cache(self):
718         clear_cached_renders(self.mini_box)
719         clear_cached_renders(self.mini_box_nolink)
720
721     def cover_info(self, inherit=True):
722         """Returns a dictionary to serve as fallback for BookInfo.
723
724         For now, the only thing inherited is the cover image.
725         """
726         need = False
727         info = {}
728         for field in ('cover_url', 'cover_by', 'cover_source'):
729             val = self.get_extra_info_json().get(field)
730             if val:
731                 info[field] = val
732             else:
733                 need = True
734         if inherit and need and self.parent is not None:
735             parent_info = self.parent.cover_info()
736             parent_info.update(info)
737             info = parent_info
738         return info
739
740     def related_themes(self):
741         return Tag.objects.usage_for_queryset(
742             Fragment.objects.filter(models.Q(book=self) | models.Q(book__ancestor=self)),
743             counts=True).filter(category='theme')
744
745     def parent_cover_changed(self):
746         """Called when parent book's cover image is changed."""
747         if not self.cover_info(inherit=False):
748             if 'cover' not in app_settings.DONT_BUILD:
749                 self.cover.build_delay()
750                 self.cover_thumb.build_delay()
751                 self.cover_api_thumb.build_delay()
752                 self.simple_cover.build_delay()
753             for format_ in constants.EBOOK_FORMATS_WITH_COVERS:
754                 if format_ not in app_settings.DONT_BUILD:
755                     getattr(self, '%s_file' % format_).build_delay()
756             for child in self.children.all():
757                 child.parent_cover_changed()
758
759     def other_versions(self):
760         """Find other versions (i.e. in other languages) of the book."""
761         return type(self).objects.filter(common_slug=self.common_slug, findable=True).exclude(pk=self.pk)
762
763     def parents(self):
764         books = []
765         parent = self.parent
766         while parent is not None:
767             books.insert(0, parent)
768             parent = parent.parent
769         return books
770
771     def pretty_title(self, html_links=False):
772         names = [(tag.name, tag.get_absolute_url()) for tag in self.authors().only('name', 'category', 'slug')]
773         books = self.parents() + [self]
774         names.extend([(b.title, b.get_absolute_url()) for b in books])
775
776         if html_links:
777             names = ['<a href="%s">%s</a>' % (tag[1], tag[0]) for tag in names]
778         else:
779             names = [tag[0] for tag in names]
780         return ', '.join(names)
781
782     def publisher(self):
783         publisher = self.get_extra_info_json()['publisher']
784         if isinstance(publisher, str):
785             return publisher
786         elif isinstance(publisher, list):
787             return ', '.join(publisher)
788
789     @classmethod
790     def tagged_top_level(cls, tags):
791         """ Returns top-level books tagged with `tags`.
792
793         It only returns those books which don't have ancestors which are
794         also tagged with those tags.
795
796         """
797         objects = cls.tagged.with_all(tags)
798         return objects.filter(findable=True).exclude(ancestor__in=objects)
799
800     @classmethod
801     def book_list(cls, book_filter=None):
802         """Generates a hierarchical listing of all books.
803
804         Books are optionally filtered with a test function.
805
806         """
807
808         books_by_parent = {}
809         books = cls.objects.filter(findable=True).order_by('parent_number', 'sort_key').only('title', 'parent', 'slug', 'extra_info')
810         if book_filter:
811             books = books.filter(book_filter).distinct()
812
813             book_ids = set(b['pk'] for b in books.values("pk").iterator())
814             for book in books.iterator():
815                 parent = book.parent_id
816                 if parent not in book_ids:
817                     parent = None
818                 books_by_parent.setdefault(parent, []).append(book)
819         else:
820             for book in books.iterator():
821                 books_by_parent.setdefault(book.parent_id, []).append(book)
822
823         orphans = []
824         books_by_author = OrderedDict()
825         for tag in Tag.objects.filter(category='author').iterator():
826             books_by_author[tag] = []
827
828         for book in books_by_parent.get(None, ()):
829             authors = list(book.authors().only('pk'))
830             if authors:
831                 for author in authors:
832                     books_by_author[author].append(book)
833             else:
834                 orphans.append(book)
835
836         return books_by_author, orphans, books_by_parent
837
838     _audiences_pl = {
839         "SP": (1, "szkoła podstawowa"),
840         "SP1": (1, "szkoła podstawowa"),
841         "SP2": (1, "szkoła podstawowa"),
842         "SP3": (1, "szkoła podstawowa"),
843         "P": (1, "szkoła podstawowa"),
844         "G": (2, "gimnazjum"),
845         "L": (3, "liceum"),
846         "LP": (3, "liceum"),
847     }
848
849     def audiences_pl(self):
850         audiences = self.get_extra_info_json().get('audiences', [])
851         audiences = sorted(set([self._audiences_pl.get(a, (99, a)) for a in audiences]))
852         return [a[1] for a in audiences]
853
854     def stage_note(self):
855         stage = self.get_extra_info_json().get('stage')
856         if stage and stage < '0.4':
857             return (_('This work needs modernisation'),
858                     reverse('infopage', args=['wymagajace-uwspolczesnienia']))
859         else:
860             return None, None
861
862     def choose_fragment(self):
863         fragments = self.fragments.order_by()
864         fragments_count = fragments.count()
865         if not fragments_count and self.children.exists():
866             fragments = Fragment.objects.filter(book__ancestor=self).order_by()
867             fragments_count = fragments.count()
868         if fragments_count:
869             return fragments[randint(0, fragments_count - 1)]
870         elif self.parent:
871             return self.parent.choose_fragment()
872         else:
873             return None
874
875     def fragment_data(self):
876         fragment = self.choose_fragment()
877         if fragment:
878             return {
879                 'title': fragment.book.pretty_title(),
880                 'html': re.sub('</?blockquote[^>]*>', '', fragment.get_short_text()),
881             }
882         else:
883             return None
884
885     def update_popularity(self):
886         count = self.tags.filter(category='set').values('user').order_by('user').distinct().count()
887         try:
888             pop = self.popularity
889             pop.count = count
890             pop.save()
891         except BookPopularity.DoesNotExist:
892             BookPopularity.objects.create(book=self, count=count)
893
894     def ridero_link(self):
895         return 'https://ridero.eu/%s/books/wl_%s/' % (get_language(), self.slug.replace('-', '_'))
896
897     def like(self, user):
898         from social.utils import likes, get_set, set_sets
899         if not likes(user, self):
900             tag = get_set(user, '')
901             set_sets(user, self, [tag])
902
903     def unlike(self, user):
904         from social.utils import likes, set_sets
905         if likes(user, self):
906             set_sets(user, self, [])
907
908     def full_sort_key(self):
909         return self.SORT_KEY_SEP.join((self.sort_key_author, self.sort_key, str(self.id)))
910
911     def cover_color(self):
912         return WLCover.epoch_colors.get(self.get_extra_info_json().get('epoch'), '#000000')
913
914     @cached_render('catalogue/book_mini_box.html')
915     def mini_box(self):
916         return {
917             'book': self
918         }
919
920     @cached_render('catalogue/book_mini_box.html')
921     def mini_box_nolink(self):
922         return {
923             'book': self,
924             'no_link': True,
925         }
926
927 def add_file_fields():
928     for format_ in Book.formats:
929         field_name = "%s_file" % format_
930         # This weird globals() assignment makes Django migrations comfortable.
931         _upload_to = _ebook_upload_to('book/%s/%%s.%s' % (format_, format_))
932         _upload_to.__name__ = '_%s_upload_to' % format_
933         globals()[_upload_to.__name__] = _upload_to
934
935         EbookField(
936             format_, _("%s file" % format_.upper()),
937             upload_to=_upload_to,
938             storage=bofh_storage,
939             max_length=255,
940             blank=True,
941             default=''
942         ).contribute_to_class(Book, field_name)
943         if format_ != 'xml':
944             models.CharField(max_length=255, editable=False, default='', db_index=True).contribute_to_class(Book, f'{field_name}_etag')
945
946
947 add_file_fields()
948
949
950 class BookPopularity(models.Model):
951     book = models.OneToOneField(Book, models.CASCADE, related_name='popularity')
952     count = models.IntegerField(default=0, db_index=True)