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[wolnelektury.git] / apps / catalogue / models.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 namedtuple
6
7 from django.db import models
8 from django.db.models import permalink
9 import django.dispatch
10 from django.core.cache import get_cache
11 from django.utils.translation import ugettext_lazy as _
12 from django.contrib.auth.models import User
13 from django.template.loader import render_to_string
14 from django.utils.datastructures import SortedDict
15 from django.utils.safestring import mark_safe
16 from django.utils.translation import get_language
17 from django.core.urlresolvers import reverse
18 from django.db.models.signals import post_save, pre_delete, post_delete
19 import jsonfield
20
21 from django.conf import settings
22
23 from newtagging.models import TagBase, tags_updated
24 from newtagging import managers
25 from catalogue.fields import OverwritingFileField
26 from catalogue.utils import create_zip, split_tags, truncate_html_words
27 from catalogue import tasks
28 import re
29
30
31 # Those are hard-coded here so that makemessages sees them.
32 TAG_CATEGORIES = (
33     ('author', _('author')),
34     ('epoch', _('epoch')),
35     ('kind', _('kind')),
36     ('genre', _('genre')),
37     ('theme', _('theme')),
38     ('set', _('set')),
39     ('book', _('book')),
40 )
41
42
43 permanent_cache = get_cache('permanent')
44
45
46 class TagSubcategoryManager(models.Manager):
47     def __init__(self, subcategory):
48         super(TagSubcategoryManager, self).__init__()
49         self.subcategory = subcategory
50
51     def get_query_set(self):
52         return super(TagSubcategoryManager, self).get_query_set().filter(category=self.subcategory)
53
54
55 class Tag(TagBase):
56     """A tag attachable to books and fragments (and possibly anything).
57     
58     Used to represent searchable metadata (authors, epochs, genres, kinds),
59     fragment themes (motifs) and some book hierarchy related kludges."""
60     name = models.CharField(_('name'), max_length=50, db_index=True)
61     slug = models.SlugField(_('slug'), max_length=120, db_index=True)
62     sort_key = models.CharField(_('sort key'), max_length=120, db_index=True)
63     category = models.CharField(_('category'), max_length=50, blank=False, null=False,
64         db_index=True, choices=TAG_CATEGORIES)
65     description = models.TextField(_('description'), blank=True)
66
67     user = models.ForeignKey(User, blank=True, null=True)
68     book_count = models.IntegerField(_('book count'), blank=True, null=True)
69     gazeta_link = models.CharField(blank=True, max_length=240)
70     wiki_link = models.CharField(blank=True, max_length=240)
71
72     created_at    = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
73     changed_at    = models.DateTimeField(_('creation date'), auto_now=True, db_index=True)
74
75     class UrlDeprecationWarning(DeprecationWarning):
76         pass
77
78     categories_rev = {
79         'autor': 'author',
80         'epoka': 'epoch',
81         'rodzaj': 'kind',
82         'gatunek': 'genre',
83         'motyw': 'theme',
84         'polka': 'set',
85     }
86     categories_dict = dict((item[::-1] for item in categories_rev.iteritems()))
87
88     class Meta:
89         ordering = ('sort_key',)
90         verbose_name = _('tag')
91         verbose_name_plural = _('tags')
92         unique_together = (("slug", "category"),)
93
94     def __unicode__(self):
95         return self.name
96
97     def __repr__(self):
98         return "Tag(slug=%r)" % self.slug
99
100     @permalink
101     def get_absolute_url(self):
102         return ('catalogue.views.tagged_object_list', [self.url_chunk])
103
104     def has_description(self):
105         return len(self.description) > 0
106     has_description.short_description = _('description')
107     has_description.boolean = True
108
109     def get_count(self):
110         """Returns global book count for book tags, fragment count for themes."""
111
112         if self.category == 'book':
113             # never used
114             objects = Book.objects.none()
115         elif self.category == 'theme':
116             objects = Fragment.tagged.with_all((self,))
117         else:
118             objects = Book.tagged.with_all((self,)).order_by()
119             if self.category != 'set':
120                 # eliminate descendants
121                 l_tags = Tag.objects.filter(slug__in=[book.book_tag_slug() for book in objects.iterator()])
122                 descendants_keys = [book.pk for book in Book.tagged.with_any(l_tags).iterator()]
123                 if descendants_keys:
124                     objects = objects.exclude(pk__in=descendants_keys)
125         return objects.count()
126
127     @staticmethod
128     def get_tag_list(tags):
129         if isinstance(tags, basestring):
130             real_tags = []
131             ambiguous_slugs = []
132             category = None
133             deprecated = False
134             tags_splitted = tags.split('/')
135             for name in tags_splitted:
136                 if category:
137                     real_tags.append(Tag.objects.get(slug=name, category=category))
138                     category = None
139                 elif name in Tag.categories_rev:
140                     category = Tag.categories_rev[name]
141                 else:
142                     try:
143                         real_tags.append(Tag.objects.exclude(category='book').get(slug=name))
144                         deprecated = True 
145                     except Tag.MultipleObjectsReturned, e:
146                         ambiguous_slugs.append(name)
147
148             if category:
149                 # something strange left off
150                 raise Tag.DoesNotExist()
151             if ambiguous_slugs:
152                 # some tags should be qualified
153                 e = Tag.MultipleObjectsReturned()
154                 e.tags = real_tags
155                 e.ambiguous_slugs = ambiguous_slugs
156                 raise e
157             if deprecated:
158                 e = Tag.UrlDeprecationWarning()
159                 e.tags = real_tags
160                 raise e
161             return real_tags
162         else:
163             return TagBase.get_tag_list(tags)
164
165     @property
166     def url_chunk(self):
167         return '/'.join((Tag.categories_dict[self.category], self.slug))
168
169     @staticmethod
170     def tags_from_info(info):
171         from slughifi import slughifi
172         from sortify import sortify
173         meta_tags = []
174         categories = (('kinds', 'kind'), ('genres', 'genre'), ('authors', 'author'), ('epochs', 'epoch'))
175         for field_name, category in categories:
176             try:
177                 tag_names = getattr(info, field_name)
178             except:
179                 try:
180                     tag_names = [getattr(info, category)]
181                 except:
182                     # For instance, Pictures do not have 'genre' field.
183                     continue
184             for tag_name in tag_names:
185                 tag_sort_key = tag_name
186                 if category == 'author':
187                     tag_sort_key = tag_name.last_name
188                     tag_name = tag_name.readable()
189                 tag, created = Tag.objects.get_or_create(slug=slughifi(tag_name), category=category)
190                 if created:
191                     tag.name = tag_name
192                     tag.sort_key = sortify(tag_sort_key.lower())
193                     tag.save()
194                 meta_tags.append(tag)
195         return meta_tags
196
197
198
199 def get_dynamic_path(media, filename, ext=None, maxlen=100):
200     from slughifi import slughifi
201
202     # how to put related book's slug here?
203     if not ext:
204         # BookMedia case
205         ext = media.formats[media.type].ext
206     if media is None or not media.name:
207         name = slughifi(filename.split(".")[0])
208     else:
209         name = slughifi(media.name)
210     return 'book/%s/%s.%s' % (ext, name[:maxlen-len('book/%s/.%s' % (ext, ext))-4], ext)
211
212
213 # TODO: why is this hard-coded ?
214 def book_upload_path(ext=None, maxlen=100):
215     return lambda *args: get_dynamic_path(*args, ext=ext, maxlen=maxlen)
216
217
218 class BookMedia(models.Model):
219     """Represents media attached to a book."""
220     FileFormat = namedtuple("FileFormat", "name ext")
221     formats = SortedDict([
222         ('mp3', FileFormat(name='MP3', ext='mp3')),
223         ('ogg', FileFormat(name='Ogg Vorbis', ext='ogg')),
224         ('daisy', FileFormat(name='DAISY', ext='daisy.zip')),
225     ])
226     format_choices = [(k, _('%s file') % t.name)
227             for k, t in formats.items()]
228
229     type        = models.CharField(_('type'), choices=format_choices, max_length="100")
230     name        = models.CharField(_('name'), max_length="100")
231     file        = OverwritingFileField(_('file'), upload_to=book_upload_path())
232     uploaded_at = models.DateTimeField(_('creation date'), auto_now_add=True, editable=False)
233     extra_info  = jsonfield.JSONField(_('extra information'), default='{}', editable=False)
234     book = models.ForeignKey('Book', related_name='media')
235     source_sha1 = models.CharField(null=True, blank=True, max_length=40, editable=False)
236
237     def __unicode__(self):
238         return "%s (%s)" % (self.name, self.file.name.split("/")[-1])
239
240     class Meta:
241         ordering            = ('type', 'name')
242         verbose_name        = _('book media')
243         verbose_name_plural = _('book media')
244
245     def save(self, *args, **kwargs):
246         from slughifi import slughifi
247         from catalogue.utils import ExistingFile, remove_zip
248
249         try:
250             old = BookMedia.objects.get(pk=self.pk)
251         except BookMedia.DoesNotExist:
252             old = None
253         else:
254             # if name changed, change the file name, too
255             if slughifi(self.name) != slughifi(old.name):
256                 self.file.save(None, ExistingFile(self.file.path), save=False, leave=True)
257
258         super(BookMedia, self).save(*args, **kwargs)
259
260         # remove the zip package for book with modified media
261         if old:
262             remove_zip("%s_%s" % (old.book.slug, old.type))
263         remove_zip("%s_%s" % (self.book.slug, self.type))
264
265         extra_info = self.extra_info
266         extra_info.update(self.read_meta())
267         self.extra_info = extra_info
268         self.source_sha1 = self.read_source_sha1(self.file.path, self.type)
269         return super(BookMedia, self).save(*args, **kwargs)
270
271     def read_meta(self):
272         """
273             Reads some metadata from the audiobook.
274         """
275         import mutagen
276         from mutagen import id3
277
278         artist_name = director_name = project = funded_by = ''
279         if self.type == 'mp3':
280             try:
281                 audio = id3.ID3(self.file.path)
282                 artist_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE1'))
283                 director_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE3'))
284                 project = ", ".join([t.data for t in audio.getall('PRIV') 
285                         if t.owner=='wolnelektury.pl?project'])
286                 funded_by = ", ".join([t.data for t in audio.getall('PRIV') 
287                         if t.owner=='wolnelektury.pl?funded_by'])
288             except:
289                 pass
290         elif self.type == 'ogg':
291             try:
292                 audio = mutagen.File(self.file.path)
293                 artist_name = ', '.join(audio.get('artist', []))
294                 director_name = ', '.join(audio.get('conductor', []))
295                 project = ", ".join(audio.get('project', []))
296                 funded_by = ", ".join(audio.get('funded_by', []))
297             except:
298                 pass
299         else:
300             return {}
301         return {'artist_name': artist_name, 'director_name': director_name,
302                 'project': project, 'funded_by': funded_by}
303
304     @staticmethod
305     def read_source_sha1(filepath, filetype):
306         """
307             Reads source file SHA1 from audiobok metadata.
308         """
309         import mutagen
310         from mutagen import id3
311
312         if filetype == 'mp3':
313             try:
314                 audio = id3.ID3(filepath)
315                 return [t.data for t in audio.getall('PRIV') 
316                         if t.owner=='wolnelektury.pl?flac_sha1'][0]
317             except:
318                 return None
319         elif filetype == 'ogg':
320             try:
321                 audio = mutagen.File(filepath)
322                 return audio.get('flac_sha1', [None])[0] 
323             except:
324                 return None
325         else:
326             return None
327
328
329 class Book(models.Model):
330     """Represents a book imported from WL-XML."""
331     title         = models.CharField(_('title'), max_length=120)
332     sort_key = models.CharField(_('sort key'), max_length=120, db_index=True, editable=False)
333     slug = models.SlugField(_('slug'), max_length=120, db_index=True,
334             unique=True)
335     common_slug = models.SlugField(_('slug'), max_length=120, db_index=True)
336     language = models.CharField(_('language code'), max_length=3, db_index=True,
337                     default=settings.CATALOGUE_DEFAULT_LANGUAGE)
338     description   = models.TextField(_('description'), blank=True)
339     created_at    = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
340     changed_at    = models.DateTimeField(_('creation date'), auto_now=True, db_index=True)
341     parent_number = models.IntegerField(_('parent number'), default=0)
342     extra_info    = jsonfield.JSONField(_('extra information'), default='{}')
343     gazeta_link   = models.CharField(blank=True, max_length=240)
344     wiki_link     = models.CharField(blank=True, max_length=240)
345     # files generated during publication
346
347     cover = models.FileField(_('cover'), upload_to=book_upload_path('png'),
348                 null=True, blank=True)
349     ebook_formats = ['pdf', 'epub', 'mobi', 'txt']
350     formats = ebook_formats + ['html', 'xml']
351
352     parent        = models.ForeignKey('self', blank=True, null=True, related_name='children')
353
354     _related_info = jsonfield.JSONField(blank=True, null=True, editable=False)
355
356     objects  = models.Manager()
357     tagged   = managers.ModelTaggedItemManager(Tag)
358     tags     = managers.TagDescriptor(Tag)
359
360     html_built = django.dispatch.Signal()
361     published = django.dispatch.Signal()
362
363     class AlreadyExists(Exception):
364         pass
365
366     class Meta:
367         ordering = ('sort_key',)
368         verbose_name = _('book')
369         verbose_name_plural = _('books')
370
371     def __unicode__(self):
372         return self.title
373
374     def save(self, force_insert=False, force_update=False, reset_short_html=True, **kwargs):
375         from sortify import sortify
376
377         self.sort_key = sortify(self.title)
378
379         ret = super(Book, self).save(force_insert, force_update)
380
381         if reset_short_html:
382             self.reset_short_html()
383
384         return ret
385
386     @permalink
387     def get_absolute_url(self):
388         return ('catalogue.views.book_detail', [self.slug])
389
390     @property
391     def name(self):
392         return self.title
393
394     def book_tag_slug(self):
395         return ('l-' + self.slug)[:120]
396
397     def book_tag(self):
398         slug = self.book_tag_slug()
399         book_tag, created = Tag.objects.get_or_create(slug=slug, category='book')
400         if created:
401             book_tag.name = self.title[:50]
402             book_tag.sort_key = self.title.lower()
403             book_tag.save()
404         return book_tag
405
406     def has_media(self, type_):
407         if type_ in Book.formats:
408             return bool(getattr(self, "%s_file" % type_))
409         else:
410             return self.media.filter(type=type_).exists()
411
412     def get_media(self, type_):
413         if self.has_media(type_):
414             if type_ in Book.formats:
415                 return getattr(self, "%s_file" % type_)
416             else:                                             
417                 return self.media.filter(type=type_)
418         else:
419             return None
420
421     def get_mp3(self):
422         return self.get_media("mp3")
423     def get_odt(self):
424         return self.get_media("odt")
425     def get_ogg(self):
426         return self.get_media("ogg")
427     def get_daisy(self):
428         return self.get_media("daisy")                       
429
430     def reset_short_html(self):
431         if self.id is None:
432             return
433
434         type(self).objects.filter(pk=self.pk).update(_related_info=None)
435         # Fragment.short_html relies on book's tags, so reset it here too
436         for fragm in self.fragments.all().iterator():
437             fragm.reset_short_html()
438
439     def has_description(self):
440         return len(self.description) > 0
441     has_description.short_description = _('description')
442     has_description.boolean = True
443
444     # ugly ugly ugly
445     def has_mp3_file(self):
446         return bool(self.has_media("mp3"))
447     has_mp3_file.short_description = 'MP3'
448     has_mp3_file.boolean = True
449
450     def has_ogg_file(self):
451         return bool(self.has_media("ogg"))
452     has_ogg_file.short_description = 'OGG'
453     has_ogg_file.boolean = True
454
455     def has_daisy_file(self):
456         return bool(self.has_media("daisy"))
457     has_daisy_file.short_description = 'DAISY'
458     has_daisy_file.boolean = True
459
460     def wldocument(self, parse_dublincore=True):
461         from catalogue.import_utils import ORMDocProvider
462         from librarian.parser import WLDocument
463
464         return WLDocument.from_file(self.xml_file.path,
465                 provider=ORMDocProvider(self),
466                 parse_dublincore=parse_dublincore)
467
468     def build_cover(self, book_info=None):
469         """(Re)builds the cover image."""
470         from StringIO import StringIO
471         from django.core.files.base import ContentFile
472         from librarian.cover import WLCover
473
474         if book_info is None:
475             book_info = self.wldocument().book_info
476
477         cover = WLCover(book_info).image()
478         imgstr = StringIO()
479         cover.save(imgstr, 'png')
480         self.cover.save(None, ContentFile(imgstr.getvalue()))
481
482     def build_html(self):
483         from django.core.files.base import ContentFile
484         from slughifi import slughifi
485         from librarian import html
486
487         meta_tags = list(self.tags.filter(
488             category__in=('author', 'epoch', 'genre', 'kind')))
489         book_tag = self.book_tag()
490
491         html_output = self.wldocument(parse_dublincore=False).as_html()
492         if html_output:
493             self.html_file.save('%s.html' % self.slug,
494                     ContentFile(html_output.get_string()))
495
496             # get ancestor l-tags for adding to new fragments
497             ancestor_tags = []
498             p = self.parent
499             while p:
500                 ancestor_tags.append(p.book_tag())
501                 p = p.parent
502
503             # Delete old fragments and create them from scratch
504             self.fragments.all().delete()
505             # Extract fragments
506             closed_fragments, open_fragments = html.extract_fragments(self.html_file.path)
507             for fragment in closed_fragments.values():
508                 try:
509                     theme_names = [s.strip() for s in fragment.themes.split(',')]
510                 except AttributeError:
511                     continue
512                 themes = []
513                 for theme_name in theme_names:
514                     if not theme_name:
515                         continue
516                     tag, created = Tag.objects.get_or_create(slug=slughifi(theme_name), category='theme')
517                     if created:
518                         tag.name = theme_name
519                         tag.sort_key = theme_name.lower()
520                         tag.save()
521                     themes.append(tag)
522                 if not themes:
523                     continue
524
525                 text = fragment.to_string()
526                 short_text = truncate_html_words(text, 15)
527                 if text == short_text:
528                     short_text = ''
529                 new_fragment = Fragment.objects.create(anchor=fragment.id, book=self,
530                     text=text, short_text=short_text)
531
532                 new_fragment.save()
533                 new_fragment.tags = set(meta_tags + themes + [book_tag] + ancestor_tags)
534             self.save()
535             self.html_built.send(sender=self)
536             return True
537         return False
538
539     # Thin wrappers for builder tasks
540     def build_pdf(self, *args, **kwargs):
541         """(Re)builds PDF."""
542         return tasks.build_pdf.delay(self.pk, *args, **kwargs)
543     def build_epub(self, *args, **kwargs):
544         """(Re)builds EPUB."""
545         return tasks.build_epub.delay(self.pk, *args, **kwargs)
546     def build_mobi(self, *args, **kwargs):
547         """(Re)builds MOBI."""
548         return tasks.build_mobi.delay(self.pk, *args, **kwargs)
549     def build_txt(self, *args, **kwargs):
550         """(Re)builds TXT."""
551         return tasks.build_txt.delay(self.pk, *args, **kwargs)
552
553     @staticmethod
554     def zip_format(format_):
555         def pretty_file_name(book):
556             return "%s/%s.%s" % (
557                 b.extra_info['author'],
558                 b.slug,
559                 format_)
560
561         field_name = "%s_file" % format_
562         books = Book.objects.filter(parent=None).exclude(**{field_name: ""})
563         paths = [(pretty_file_name(b), getattr(b, field_name).path)
564                     for b in books.iterator()]
565         return create_zip(paths,
566                     getattr(settings, "ALL_%s_ZIP" % format_.upper()))
567
568     def zip_audiobooks(self, format_):
569         bm = BookMedia.objects.filter(book=self, type=format_)
570         paths = map(lambda bm: (None, bm.file.path), bm)
571         return create_zip(paths, "%s_%s" % (self.slug, format_))
572
573     def search_index(self, book_info=None, reuse_index=False, index_tags=True):
574         import search
575         if reuse_index:
576             idx = search.ReusableIndex()
577         else:
578             idx = search.Index()
579             
580         idx.open()
581         try:
582             idx.index_book(self, book_info)
583             if index_tags:
584                 idx.index_tags()
585         finally:
586             idx.close()
587
588     @classmethod
589     def from_xml_file(cls, xml_file, **kwargs):
590         from django.core.files import File
591         from librarian import dcparser
592
593         # use librarian to parse meta-data
594         book_info = dcparser.parse(xml_file)
595
596         if not isinstance(xml_file, File):
597             xml_file = File(open(xml_file))
598
599         try:
600             return cls.from_text_and_meta(xml_file, book_info, **kwargs)
601         finally:
602             xml_file.close()
603
604     @classmethod
605     def from_text_and_meta(cls, raw_file, book_info, overwrite=False,
606             build_epub=True, build_txt=True, build_pdf=True, build_mobi=True,
607             search_index=True, search_index_tags=True, search_index_reuse=False):
608
609         # check for parts before we do anything
610         children = []
611         if hasattr(book_info, 'parts'):
612             for part_url in book_info.parts:
613                 try:
614                     children.append(Book.objects.get(slug=part_url.slug))
615                 except Book.DoesNotExist:
616                     raise Book.DoesNotExist(_('Book "%s" does not exist.') %
617                             part_url.slug)
618
619
620         # Read book metadata
621         book_slug = book_info.url.slug
622         if re.search(r'[^a-z0-9-]', book_slug):
623             raise ValueError('Invalid characters in slug')
624         book, created = Book.objects.get_or_create(slug=book_slug)
625
626         if created:
627             book_shelves = []
628         else:
629             if not overwrite:
630                 raise Book.AlreadyExists(_('Book %s already exists') % (
631                         book_slug))
632             # Save shelves for this book
633             book_shelves = list(book.tags.filter(category='set'))
634
635         book.language = book_info.language
636         book.title = book_info.title
637         if book_info.variant_of:
638             book.common_slug = book_info.variant_of.slug
639         else:
640             book.common_slug = book.slug
641         book.extra_info = book_info.to_dict()
642         book.save()
643
644         meta_tags = Tag.tags_from_info(book_info)
645
646         book.tags = set(meta_tags + book_shelves)
647
648         book_tag = book.book_tag()
649
650         for n, child_book in enumerate(children):
651             child_book.parent = book
652             child_book.parent_number = n
653             child_book.save()
654
655         # Save XML and HTML files
656         book.xml_file.save('%s.xml' % book.slug, raw_file, save=False)
657
658         # delete old fragments when overwriting
659         book.fragments.all().delete()
660
661         if book.build_html():
662             if not settings.NO_BUILD_TXT and build_txt:
663                 book.build_txt()
664
665         book.build_cover(book_info)
666
667         if not settings.NO_BUILD_EPUB and build_epub:
668             book.build_epub()
669
670         if not settings.NO_BUILD_PDF and build_pdf:
671             book.build_pdf()
672
673         if not settings.NO_BUILD_MOBI and build_mobi:
674             book.build_mobi()
675
676         if not settings.NO_SEARCH_INDEX and search_index:
677             book.search_index(index_tags=search_index_tags, reuse_index=search_index_reuse)
678             #index_book.delay(book.id, book_info)
679
680         book_descendants = list(book.children.all())
681         descendants_tags = set()
682         # add l-tag to descendants and their fragments
683         while len(book_descendants) > 0:
684             child_book = book_descendants.pop(0)
685             descendants_tags.update(child_book.tags)
686             child_book.tags = list(child_book.tags) + [book_tag]
687             child_book.save()
688             for fragment in child_book.fragments.all().iterator():
689                 fragment.tags = set(list(fragment.tags) + [book_tag])
690             book_descendants += list(child_book.children.all())
691
692         for tag in descendants_tags:
693             tasks.touch_tag(tag)
694
695         book.save()
696
697         # refresh cache
698         book.reset_tag_counter()
699         book.reset_theme_counter()
700
701         cls.published.send(sender=book)
702         return book
703
704     def related_info(self):
705         """Keeps info about related objects (tags, media) in cache field."""
706         if self._related_info is not None:
707             return self._related_info
708         else:
709             rel = {'tags': {}, 'media': {}}
710
711             tags = self.tags.filter(category__in=(
712                     'author', 'kind', 'genre', 'epoch'))
713             tags = split_tags(tags)
714             for category in tags:
715                 rel['tags'][category] = [
716                         (t.name, t.slug) for t in tags[category]]
717
718             for media_format in BookMedia.formats:
719                 rel['media'][media_format] = self.has_media(media_format)
720
721             book = self
722             parents = []
723             while book.parent:
724                 parents.append((book.parent.title, book.parent.slug))
725                 book = book.parent
726             parents = parents[::-1]
727             if parents:
728                 rel['parents'] = parents
729
730             if self.pk:
731                 type(self).objects.filter(pk=self.pk).update(_related_info=rel)
732             return rel
733
734     def related_themes(self):
735         theme_counter = self.theme_counter
736         book_themes = list(Tag.objects.filter(pk__in=theme_counter.keys()))
737         for tag in book_themes:
738             tag.count = theme_counter[tag.pk]
739         return book_themes
740
741     def reset_tag_counter(self):
742         if self.id is None:
743             return
744
745         cache_key = "Book.tag_counter/%d" % self.id
746         permanent_cache.delete(cache_key)
747         if self.parent:
748             self.parent.reset_tag_counter()
749
750     @property
751     def tag_counter(self):
752         if self.id:
753             cache_key = "Book.tag_counter/%d" % self.id
754             tags = permanent_cache.get(cache_key)
755         else:
756             tags = None
757
758         if tags is None:
759             tags = {}
760             for child in self.children.all().order_by().iterator():
761                 for tag_pk, value in child.tag_counter.iteritems():
762                     tags[tag_pk] = tags.get(tag_pk, 0) + value
763             for tag in self.tags.exclude(category__in=('book', 'theme', 'set')).order_by().iterator():
764                 tags[tag.pk] = 1
765
766             if self.id:
767                 permanent_cache.set(cache_key, tags)
768         return tags
769
770     def reset_theme_counter(self):
771         if self.id is None:
772             return
773
774         cache_key = "Book.theme_counter/%d" % self.id
775         permanent_cache.delete(cache_key)
776         if self.parent:
777             self.parent.reset_theme_counter()
778
779     @property
780     def theme_counter(self):
781         if self.id:
782             cache_key = "Book.theme_counter/%d" % self.id
783             tags = permanent_cache.get(cache_key)
784         else:
785             tags = None
786
787         if tags is None:
788             tags = {}
789             for fragment in Fragment.tagged.with_any([self.book_tag()]).order_by().iterator():
790                 for tag in fragment.tags.filter(category='theme').order_by().iterator():
791                     tags[tag.pk] = tags.get(tag.pk, 0) + 1
792
793             if self.id:
794                 permanent_cache.set(cache_key, tags)
795         return tags
796
797     def pretty_title(self, html_links=False):
798         book = self
799         names = list(book.tags.filter(category='author'))
800
801         books = []
802         while book:
803             books.append(book)
804             book = book.parent
805         names.extend(reversed(books))
806
807         if html_links:
808             names = ['<a href="%s">%s</a>' % (tag.get_absolute_url(), tag.name) for tag in names]
809         else:
810             names = [tag.name for tag in names]
811
812         return ', '.join(names)
813
814     @classmethod
815     def tagged_top_level(cls, tags):
816         """ Returns top-level books tagged with `tags`.
817
818         It only returns those books which don't have ancestors which are
819         also tagged with those tags.
820
821         """
822         # get relevant books and their tags
823         objects = cls.tagged.with_all(tags)
824         # eliminate descendants
825         l_tags = Tag.objects.filter(category='book',
826             slug__in=[book.book_tag_slug() for book in objects.iterator()])
827         descendants_keys = [book.pk for book in cls.tagged.with_any(l_tags).iterator()]
828         if descendants_keys:
829             objects = objects.exclude(pk__in=descendants_keys)
830
831         return objects
832
833     @classmethod
834     def book_list(cls, filter=None):
835         """Generates a hierarchical listing of all books.
836
837         Books are optionally filtered with a test function.
838
839         """
840
841         books_by_parent = {}
842         books = cls.objects.all().order_by('parent_number', 'sort_key').only(
843                 'title', 'parent', 'slug')
844         if filter:
845             books = books.filter(filter).distinct()
846             
847             book_ids = set(b['pk'] for b in books.values("pk").iterator())
848             for book in books.iterator():
849                 parent = book.parent_id
850                 if parent not in book_ids:
851                     parent = None
852                 books_by_parent.setdefault(parent, []).append(book)
853         else:
854             for book in books.iterator():
855                 books_by_parent.setdefault(book.parent_id, []).append(book)
856
857         orphans = []
858         books_by_author = SortedDict()
859         for tag in Tag.objects.filter(category='author').iterator():
860             books_by_author[tag] = []
861
862         for book in books_by_parent.get(None,()):
863             authors = list(book.tags.filter(category='author'))
864             if authors:
865                 for author in authors:
866                     books_by_author[author].append(book)
867             else:
868                 orphans.append(book)
869
870         return books_by_author, orphans, books_by_parent
871
872     _audiences_pl = {
873         "SP1": (1, u"szkoła podstawowa"),
874         "SP2": (1, u"szkoła podstawowa"),
875         "P": (1, u"szkoła podstawowa"),
876         "G": (2, u"gimnazjum"),
877         "L": (3, u"liceum"),
878         "LP": (3, u"liceum"),
879     }
880     def audiences_pl(self):
881         audiences = self.extra_info.get('audiences', [])
882         audiences = sorted(set([self._audiences_pl[a] for a in audiences]))
883         return [a[1] for a in audiences]
884
885     def choose_fragment(self):
886         tag = self.book_tag()
887         fragments = Fragment.tagged.with_any([tag])
888         if fragments.exists():
889             return fragments.order_by('?')[0]
890         elif self.parent:
891             return self.parent.choose_fragment()
892         else:
893             return None
894
895
896 def _has_factory(ftype):
897     has = lambda self: bool(getattr(self, "%s_file" % ftype))
898     has.short_description = ftype.upper()
899     has.__doc__ = None
900     has.boolean = True
901     has.__name__ = "has_%s_file" % ftype
902     return has
903
904     
905 # add the file fields
906 for t in Book.formats:
907     field_name = "%s_file" % t
908     models.FileField(_("%s file" % t.upper()),
909             upload_to=book_upload_path(t),
910             blank=True).contribute_to_class(Book, field_name)
911
912     setattr(Book, "has_%s_file" % t, _has_factory(t))
913
914
915 class Fragment(models.Model):
916     """Represents a themed fragment of a book."""
917     text = models.TextField()
918     short_text = models.TextField(editable=False)
919     anchor = models.CharField(max_length=120)
920     book = models.ForeignKey(Book, related_name='fragments')
921
922     objects = models.Manager()
923     tagged = managers.ModelTaggedItemManager(Tag)
924     tags = managers.TagDescriptor(Tag)
925
926     class Meta:
927         ordering = ('book', 'anchor',)
928         verbose_name = _('fragment')
929         verbose_name_plural = _('fragments')
930
931     def get_absolute_url(self):
932         return '%s#m%s' % (reverse('book_text', args=[self.book.slug]), self.anchor)
933
934     def reset_short_html(self):
935         if self.id is None:
936             return
937
938         cache_key = "Fragment.short_html/%d/%s"
939         for lang, langname in settings.LANGUAGES:
940             permanent_cache.delete(cache_key % (self.id, lang))
941
942     def get_short_text(self):
943         """Returns short version of the fragment."""
944         return self.short_text if self.short_text else self.text
945
946     def short_html(self):
947         if self.id:
948             cache_key = "Fragment.short_html/%d/%s" % (self.id, get_language())
949             short_html = permanent_cache.get(cache_key)
950         else:
951             short_html = None
952
953         if short_html is not None:
954             return mark_safe(short_html)
955         else:
956             short_html = unicode(render_to_string('catalogue/fragment_short.html',
957                 {'fragment': self}))
958             if self.id:
959                 permanent_cache.set(cache_key, short_html)
960             return mark_safe(short_html)
961
962
963 class Collection(models.Model):
964     """A collection of books, which might be defined before publishing them."""
965     title = models.CharField(_('title'), max_length=120, db_index=True)
966     slug = models.SlugField(_('slug'), max_length=120, primary_key=True)
967     description = models.TextField(_('description'), null=True, blank=True)
968
969     models.SlugField(_('slug'), max_length=120, unique=True, db_index=True)
970     book_slugs = models.TextField(_('book slugs'))
971
972     class Meta:
973         ordering = ('title',)
974         verbose_name = _('collection')
975         verbose_name_plural = _('collections')
976
977     def __unicode__(self):
978         return self.title
979
980
981 ###########
982 #
983 # SIGNALS
984 #
985 ###########
986
987
988 def _tags_updated_handler(sender, affected_tags, **kwargs):
989     # reset tag global counter
990     # we want Tag.changed_at updated for API to know the tag was touched
991     for tag in affected_tags:
992         tasks.touch_tag(tag)
993
994     # if book tags changed, reset book tag counter
995     if isinstance(sender, Book) and \
996                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
997                     exclude(category__in=('book', 'theme', 'set')).count():
998         sender.reset_tag_counter()
999     # if fragment theme changed, reset book theme counter
1000     elif isinstance(sender, Fragment) and \
1001                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
1002                     filter(category='theme').count():
1003         sender.book.reset_theme_counter()
1004 tags_updated.connect(_tags_updated_handler)
1005
1006
1007 def _pre_delete_handler(sender, instance, **kwargs):
1008     """ refresh Book on BookMedia delete """
1009     if sender == BookMedia:
1010         instance.book.save()
1011 pre_delete.connect(_pre_delete_handler)
1012
1013
1014 def _post_save_handler(sender, instance, **kwargs):
1015     """ refresh all the short_html stuff on BookMedia update """
1016     if sender == BookMedia:
1017         instance.book.save()
1018 post_save.connect(_post_save_handler)
1019
1020
1021 if not settings.NO_SEARCH_INDEX:
1022     @django.dispatch.receiver(post_delete, sender=Book)
1023     def _remove_book_from_index_handler(sender, instance, **kwargs):
1024         """ remove the book from search index, when it is deleted."""
1025         import search
1026         search.JVM.attachCurrentThread()
1027         idx = search.Index()
1028         idx.open(timeout=10000)  # 10 seconds timeout.
1029         try:
1030             idx.remove_book(instance)
1031             idx.index_tags()
1032         finally:
1033             idx.close()