mobileinit parent fix

[wolnelektury.git] / apps / catalogue / models.py

diff --git a/apps/catalogue/models.py b/apps/catalogue/models.py
index 1d0b83b..2722286 100644 (file)
--- a/apps/catalogue/models.py
+++ b/apps/catalogue/models.py
@@ -2,25 +2,31 @@
 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 #
 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 #

+from datetime import datetime
+

 from django.db import models
 from django.db.models import permalink, Q
 from django.utils.translation import ugettext_lazy as _
 from django.contrib.auth.models import User
 from django.core.files import File
 from django.template.loader import render_to_string
 from django.db import models
 from django.db.models import permalink, Q
 from django.utils.translation import ugettext_lazy as _
 from django.contrib.auth.models import User
 from django.core.files import File
 from django.template.loader import render_to_string

-from django.template.defaultfilters import slugify

 from django.utils.safestring import mark_safe
 from django.utils.translation import get_language
 from django.core.urlresolvers import reverse
 from django.utils.safestring import mark_safe
 from django.utils.translation import get_language
 from django.core.urlresolvers import reverse

+from django.db.models.signals import post_save, m2m_changed, pre_delete

 
 from django.conf import settings
 
 from newtagging.models import TagBase, tags_updated
 from newtagging import managers
 
 from django.conf import settings
 
 from newtagging.models import TagBase, tags_updated
 from newtagging import managers

-from catalogue.fields import JSONField
+from catalogue.fields import JSONField, OverwritingFileField
+from catalogue.utils import ExistingFile

 
 from librarian import dcparser, html, epub, NoDublinCore
 
 from librarian import dcparser, html, epub, NoDublinCore

+import mutagen

 from mutagen import id3
 from mutagen import id3

+from slughifi import slughifi
+from sortify import sortify

 
 
 TAG_CATEGORIES = (
 
 
 TAG_CATEGORIES = (


@@ -59,10 +65,16 @@ class Tag(TagBase):
     main_page = models.BooleanField(_('main page'), default=False, db_index=True, help_text=_('Show tag on main page'))
 
     user = models.ForeignKey(User, blank=True, null=True)
     main_page = models.BooleanField(_('main page'), default=False, db_index=True, help_text=_('Show tag on main page'))
 
     user = models.ForeignKey(User, blank=True, null=True)

-    book_count = models.IntegerField(_('book count'), blank=False, null=True)
+    book_count = models.IntegerField(_('book count'), blank=True, null=True)

     gazeta_link = models.CharField(blank=True, max_length=240)
     wiki_link = models.CharField(blank=True, max_length=240)
 
     gazeta_link = models.CharField(blank=True, max_length=240)
     wiki_link = models.CharField(blank=True, max_length=240)
 

+    created_at    = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
+    changed_at    = models.DateTimeField(_('creation date'), auto_now=True, db_index=True)
+
+    class UrlDeprecationWarning(DeprecationWarning):
+        pass
+

     categories_rev = {
         'autor': 'author',
         'epoka': 'epoch',
     categories_rev = {
         'autor': 'author',
         'epoka': 'epoch',


@@ -121,19 +133,20 @@ class Tag(TagBase):
             real_tags = []
             ambiguous_slugs = []
             category = None
             real_tags = []
             ambiguous_slugs = []
             category = None

+            deprecated = False

             tags_splitted = tags.split('/')
             tags_splitted = tags.split('/')

-            for index, name in enumerate(tags_splitted):
-                if name in Tag.categories_rev:
+            for name in tags_splitted:
+                if category:
+                    real_tags.append(Tag.objects.get(slug=name, category=category))
+                    category = None
+                elif name in Tag.categories_rev:

                     category = Tag.categories_rev[name]
                 else:
                     category = Tag.categories_rev[name]
                 else:

-                    if category:
-                        real_tags.append(Tag.objects.get(slug=name, category=category))
-                        category = None
-                    else:
-                        try:
-                            real_tags.append(Tag.objects.exclude(category='book').get(slug=name))
-                        except Tag.MultipleObjectsReturned, e:
-                            ambiguous_slugs.append(name)
+                    try:
+                        real_tags.append(Tag.objects.exclude(category='book').get(slug=name))
+                        deprecated = True 
+                    except Tag.MultipleObjectsReturned, e:
+                        ambiguous_slugs.append(name)

 
             if category:
                 # something strange left off
 
             if category:
                 # something strange left off


@@ -144,8 +157,11 @@ class Tag(TagBase):
                 e.tags = real_tags
                 e.ambiguous_slugs = ambiguous_slugs
                 raise e
                 e.tags = real_tags
                 e.ambiguous_slugs = ambiguous_slugs
                 raise e

-            else:
-                return real_tags
+            if deprecated:
+                e = Tag.UrlDeprecationWarning()
+                e.tags = real_tags
+                raise e
+            return real_tags

         else:
             return TagBase.get_tag_list(tags)
 
         else:
             return TagBase.get_tag_list(tags)
 


@@ -155,24 +171,30 @@ class Tag(TagBase):
 
 
 # TODO: why is this hard-coded ?
 
 
 # TODO: why is this hard-coded ?

-def book_upload_path(ext=None):
+def book_upload_path(ext=None, maxlen=100):

     def get_dynamic_path(media, filename, ext=ext):
         # how to put related book's slug here?
         if not ext:
     def get_dynamic_path(media, filename, ext=ext):
         # how to put related book's slug here?
         if not ext:

-            ext = media.type
+            if media.type == 'daisy':
+                ext = 'daisy.zip'
+            else:
+                ext = media.type

         if not media.name:
         if not media.name:

-            name = slugify(filename.split(".")[0])
+            name = slughifi(filename.split(".")[0])

         else:
         else:

-            name = slugify(media.name)
-        return 'lektura/%s.%s' % (name, ext)
+            name = slughifi(media.name)
+        return 'book/%s/%s.%s' % (ext, name[:maxlen-len('book/%s/.%s' % (ext, ext))-4], ext)

     return get_dynamic_path
 
 
 class BookMedia(models.Model):
     type        = models.CharField(_('type'), choices=MEDIA_FORMATS, max_length="100")
     return get_dynamic_path
 
 
 class BookMedia(models.Model):
     type        = models.CharField(_('type'), choices=MEDIA_FORMATS, max_length="100")

-    name        = models.CharField(_('name'), max_length="100", blank=True)
-    file        = models.FileField(_('file'), upload_to=book_upload_path(), blank=True)    
+    name        = models.CharField(_('name'), max_length="100")
+    file        = OverwritingFileField(_('file'), upload_to=book_upload_path())

     uploaded_at = models.DateTimeField(_('creation date'), auto_now_add=True, editable=False)
     uploaded_at = models.DateTimeField(_('creation date'), auto_now_add=True, editable=False)

+    extra_info  = JSONField(_('extra information'), default='{}', editable=False)
+    book = models.ForeignKey('Book', related_name='media')
+    source_sha1 = models.CharField(null=True, blank=True, max_length=40, editable=False)

 
     def __unicode__(self):
         return "%s (%s)" % (self.name, self.file.name.split("/")[-1])
 
     def __unicode__(self):
         return "%s (%s)" % (self.name, self.file.name.split("/")[-1])


@@ -182,14 +204,87 @@ class BookMedia(models.Model):
         verbose_name        = _('book media')
         verbose_name_plural = _('book media')
 
         verbose_name        = _('book media')
         verbose_name_plural = _('book media')
 

+    def save(self, *args, **kwargs):
+        try:
+            old = BookMedia.objects.get(pk=self.pk)
+        except BookMedia.DoesNotExist, e:
+            pass
+        else:
+            # if name changed, change the file name, too
+            if slughifi(self.name) != slughifi(old.name):
+                self.file.save(None, ExistingFile(self.file.path), save=False, leave=True)
+
+        super(BookMedia, self).save(*args, **kwargs)
+        extra_info = self.get_extra_info_value()
+        extra_info.update(self.read_meta())
+        self.set_extra_info_value(extra_info)
+        self.source_sha1 = self.read_source_sha1(self.file.path, self.type)
+        return super(BookMedia, self).save(*args, **kwargs)
+
+    def read_meta(self):
+        """
+            Reads some metadata from the audiobook.
+        """
+
+        artist_name = director_name = project = funded_by = ''
+        if self.type == 'mp3':
+            try:
+                audio = id3.ID3(self.file.path)
+                artist_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE1'))
+                director_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE3'))
+                project = ", ".join([t.data for t in audio.getall('PRIV') 
+                        if t.owner=='wolnelektury.pl?project'])
+                funded_by = ", ".join([t.data for t in audio.getall('PRIV') 
+                        if t.owner=='wolnelektury.pl?funded_by'])
+            except:
+                pass
+        elif self.type == 'ogg':
+            try:
+                audio = mutagen.File(self.file.path)
+                artist_name = ', '.join(audio.get('artist', []))
+                director_name = ', '.join(audio.get('conductor', []))
+                project = ", ".join(audio.get('project', []))
+                funded_by = ", ".join(audio.get('funded_by', []))
+            except:
+                pass
+        else:
+            return {}
+        return {'artist_name': artist_name, 'director_name': director_name,
+                'project': project, 'funded_by': funded_by}
+
+    @staticmethod
+    def read_source_sha1(filepath, filetype):
+        """
+            Reads source file SHA1 from audiobok metadata.
+        """
+
+        if filetype == 'mp3':
+            try:
+                audio = id3.ID3(filepath)
+                return [t.data for t in audio.getall('PRIV') 
+                        if t.owner=='wolnelektury.pl?flac_sha1'][0]
+            except:
+                return None
+        elif filetype == 'ogg':
+            try:
+                audio = mutagen.File(filepath)
+                return audio.get('flac_sha1', [None])[0] 
+            except:
+                return None
+        else:
+            return None
+
+

 class Book(models.Model):
     title         = models.CharField(_('title'), max_length=120)
 class Book(models.Model):
     title         = models.CharField(_('title'), max_length=120)

+    sort_key = models.CharField(_('sort_key'), max_length=120, db_index=True, editable=False)

     slug          = models.SlugField(_('slug'), max_length=120, unique=True, db_index=True)
     description   = models.TextField(_('description'), blank=True)
     slug          = models.SlugField(_('slug'), max_length=120, unique=True, db_index=True)
     description   = models.TextField(_('description'), blank=True)

-    created_at    = models.DateTimeField(_('creation date'), auto_now_add=True)
+    created_at    = models.DateTimeField(_('creation date'), auto_now_add=True, db_index=True)
+    changed_at    = models.DateTimeField(_('creation date'), auto_now=True, db_index=True)

     _short_html   = models.TextField(_('short HTML'), editable=False)
     parent_number = models.IntegerField(_('parent number'), default=0)
     _short_html   = models.TextField(_('short HTML'), editable=False)
     parent_number = models.IntegerField(_('parent number'), default=0)

-    extra_info    = JSONField(_('extra information'))
+    extra_info    = JSONField(_('extra information'), default='{}')

     gazeta_link   = models.CharField(blank=True, max_length=240)
     wiki_link     = models.CharField(blank=True, max_length=240)
     # files generated during publication
     gazeta_link   = models.CharField(blank=True, max_length=240)
     wiki_link     = models.CharField(blank=True, max_length=240)
     # files generated during publication


@@ -198,9 +293,7 @@ class Book(models.Model):
     pdf_file      = models.FileField(_('PDF file'), upload_to=book_upload_path('pdf'), blank=True)
     epub_file     = models.FileField(_('EPUB file'), upload_to=book_upload_path('epub'), blank=True)    
     txt_file      = models.FileField(_('TXT file'), upload_to=book_upload_path('txt'), blank=True)        
     pdf_file      = models.FileField(_('PDF file'), upload_to=book_upload_path('pdf'), blank=True)
     epub_file     = models.FileField(_('EPUB file'), upload_to=book_upload_path('epub'), blank=True)    
     txt_file      = models.FileField(_('TXT file'), upload_to=book_upload_path('txt'), blank=True)        

-    # other files
-    medias        = models.ManyToManyField(BookMedia, blank=True)
-    
+

     parent        = models.ForeignKey('self', blank=True, null=True, related_name='children')
     objects  = models.Manager()
     tagged   = managers.ModelTaggedItemManager(Tag)
     parent        = models.ForeignKey('self', blank=True, null=True, related_name='children')
     objects  = models.Manager()
     tagged   = managers.ModelTaggedItemManager(Tag)


@@ -213,14 +306,16 @@ class Book(models.Model):
         pass
 
     class Meta:
         pass
 
     class Meta:

-        ordering = ('title',)
+        ordering = ('sort_key',)

         verbose_name = _('book')
         verbose_name_plural = _('books')
 
     def __unicode__(self):
         return self.title
 
         verbose_name = _('book')
         verbose_name_plural = _('books')
 
     def __unicode__(self):
         return self.title
 

-    def save(self, force_insert=False, force_update=False, reset_short_html=True, refresh_mp3=True, **kwargs):
+    def save(self, force_insert=False, force_update=False, reset_short_html=True, **kwargs):
+        self.sort_key = sortify(self.title)
+

         if reset_short_html:
             # Reset _short_html during save
             update = {}
         if reset_short_html:
             # Reset _short_html during save
             update = {}


@@ -230,16 +325,7 @@ class Book(models.Model):
             # Fragment.short_html relies on book's tags, so reset it here too
             self.fragments.all().update(**update)
 
             # Fragment.short_html relies on book's tags, so reset it here too
             self.fragments.all().update(**update)
 

-        book = super(Book, self).save(force_insert, force_update)
-
-        if refresh_mp3 and self.has_media('mp3'):
-            file = self.get_media('mp3')[0]
-            #print file, file.path
-            extra_info = self.get_extra_info_value()
-            extra_info.update(self.get_mp3_info())
-            self.set_extra_info_value(extra_info)
-            book = super(Book, self).save(force_insert, force_update)
-        return book
+        return super(Book, self).save(force_insert, force_update)

 
     @permalink
     def get_absolute_url(self):
 
     @permalink
     def get_absolute_url(self):


@@ -288,7 +374,7 @@ class Book(models.Model):
             else:
                 return False                          
         else:
             else:
                 return False                          
         else:

-            if self.medias.filter(book=self, type=type).count() > 0:
+            if self.media.filter(type=type).exists():

                 return True
             else:
                 return False
                 return True
             else:
                 return False


@@ -300,13 +386,13 @@ class Book(models.Model):
             elif type == "html":
                 return self.html_file
             elif type == "epub":
             elif type == "html":
                 return self.html_file
             elif type == "epub":

-                return self.html_file                
+                return self.epub_file

             elif type == "txt":
                 return self.txt_file
             elif type == "pdf":
                 return self.pdf_file
             else:                                             
             elif type == "txt":
                 return self.txt_file
             elif type == "pdf":
                 return self.pdf_file
             else:                                             

-                return self.medias.filter(book=self, type=type)
+                return self.media.filter(type=type)

         else:
             return None
 
         else:
             return None
 


@@ -337,13 +423,11 @@ class Book(models.Model):
                 formats.append(u'<a href="%s">PDF</a>' % self.get_media('pdf').url)
             if self.root_ancestor.has_media("epub"):
                 formats.append(u'<a href="%s">EPUB</a>' % self.root_ancestor.get_media('epub').url)
                 formats.append(u'<a href="%s">PDF</a>' % self.get_media('pdf').url)
             if self.root_ancestor.has_media("epub"):
                 formats.append(u'<a href="%s">EPUB</a>' % self.root_ancestor.get_media('epub').url)

-            if self.has_media("odt"):
-                formats.append(u'<a href="%s">ODT</a>' % self.get_media('odt').url)

             if self.has_media("txt"):
                 formats.append(u'<a href="%s">TXT</a>' % self.get_media('txt').url)
             # other files
             if self.has_media("txt"):
                 formats.append(u'<a href="%s">TXT</a>' % self.get_media('txt').url)
             # other files

-            for m in self.medias.order_by('type'):
-                formats.append(u'<a href="%s">%s</a>' % m.type, m.file.url)
+            for m in self.media.order_by('type'):
+                formats.append(u'<a href="%s">%s</a>' % (m.file.url, m.type.upper()))

 
             formats = [mark_safe(format) for format in formats]
 
 
             formats = [mark_safe(format) for format in formats]
 


@@ -365,13 +449,6 @@ class Book(models.Model):
         return self._root_ancestor
 
 
         return self._root_ancestor
 
 

-    def get_mp3_info(self):
-        """Retrieves artist and director names from audio ID3 tags."""
-        audio = id3.ID3(self.get_media('mp3')[0].file.path)
-        artist_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE1'))
-        director_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE3'))
-        return {'artist_name': artist_name, 'director_name': director_name}
-

     def has_description(self):
         return len(self.description) > 0
     has_description.short_description = _('description')
     def has_description(self):
         return len(self.description) > 0
     has_description.short_description = _('description')


@@ -388,6 +465,11 @@ class Book(models.Model):
     has_epub_file.short_description = 'EPUB'
     has_epub_file.boolean = True
 
     has_epub_file.short_description = 'EPUB'
     has_epub_file.boolean = True
 

+    def has_txt_file(self):
+        return bool(self.txt_file)
+    has_txt_file.short_description = 'HTML'
+    has_txt_file.boolean = True
+

     def has_html_file(self):
         return bool(self.html_file)
     has_html_file.short_description = 'HTML'
     def has_html_file(self):
         return bool(self.html_file)
     has_html_file.short_description = 'HTML'


@@ -442,9 +524,8 @@ class Book(models.Model):
 
         epub_file = StringIO()
         try:
 
         epub_file = StringIO()
         try:

-            epub.transform(BookImportDocProvider(self), self.slug, epub_file)
-            self.epub_file.save('%s.epub' % self.slug, ContentFile(epub_file.getvalue()), save=False)
-            self.save(refresh_mp3=False)
+            epub.transform(BookImportDocProvider(self), self.slug, output_file=epub_file)
+            self.epub_file.save('%s.epub' % self.slug, ContentFile(epub_file.getvalue()))

             FileRecord(slug=self.slug, type='epub', sha1=sha1(epub_file.getvalue()).hexdigest()).save()
         except NoDublinCore:
             pass
             FileRecord(slug=self.slug, type='epub', sha1=sha1(epub_file.getvalue()).hexdigest()).save()
         except NoDublinCore:
             pass


@@ -455,12 +536,22 @@ class Book(models.Model):
             if remove_descendants and child_book.has_epub_file():
                 child_book.epub_file.delete()
             # save anyway, to refresh short_html
             if remove_descendants and child_book.has_epub_file():
                 child_book.epub_file.delete()
             # save anyway, to refresh short_html

-            child_book.save(refresh_mp3=False)
+            child_book.save()

             book_descendants += list(child_book.children.all())
 
             book_descendants += list(child_book.children.all())
 

+    def build_txt(self):
+        from StringIO import StringIO
+        from django.core.files.base import ContentFile
+        from librarian import text
+
+        out = StringIO()
+        text.transform(open(self.xml_file.path), out)
+        self.txt_file.save('%s.txt' % self.slug, ContentFile(out.getvalue()))
+        self.save()
+

 
     @classmethod
 
     @classmethod

-    def from_xml_file(cls, xml_file, overwrite=False):
+    def from_xml_file(cls, xml_file, **kwargs):

         # use librarian to parse meta-data
         book_info = dcparser.parse(xml_file)
 
         # use librarian to parse meta-data
         book_info = dcparser.parse(xml_file)
 


@@ -468,14 +559,14 @@ class Book(models.Model):
             xml_file = File(open(xml_file))
 
         try:
             xml_file = File(open(xml_file))
 
         try:

-            return cls.from_text_and_meta(xml_file, book_info, overwrite)
+            return cls.from_text_and_meta(xml_file, book_info, **kwargs)

         finally:
             xml_file.close()
 
     @classmethod
         finally:
             xml_file.close()
 
     @classmethod

-    def from_text_and_meta(cls, raw_file, book_info, overwrite=False):
+    def from_text_and_meta(cls, raw_file, book_info, overwrite=False, build_epub=True, build_txt=True):
+        import re

         from tempfile import NamedTemporaryFile
         from tempfile import NamedTemporaryFile

-        from slughifi import slughifi

         from markupstring import MarkupString
         from django.core.files.storage import default_storage
 
         from markupstring import MarkupString
         from django.core.files.storage import default_storage
 


@@ -492,6 +583,8 @@ class Book(models.Model):
 
         # Read book metadata
         book_base, book_slug = book_info.url.rsplit('/', 1)
 
         # Read book metadata
         book_base, book_slug = book_info.url.rsplit('/', 1)

+        if re.search(r'[^a-zA-Z0-9-]', book_slug):
+            raise ValueError('Invalid characters in slug')

         book, created = Book.objects.get_or_create(slug=book_slug)
 
         if created:
         book, created = Book.objects.get_or_create(slug=book_slug)
 
         if created:


@@ -522,11 +615,11 @@ class Book(models.Model):
                 tag, created = Tag.objects.get_or_create(slug=slughifi(tag_name), category=category)
                 if created:
                     tag.name = tag_name
                 tag, created = Tag.objects.get_or_create(slug=slughifi(tag_name), category=category)
                 if created:
                     tag.name = tag_name

-                    tag.sort_key = tag_sort_key.lower()
+                    tag.sort_key = sortify(tag_sort_key.lower())

                     tag.save()
                 book_tags.append(tag)
 
                     tag.save()
                 book_tags.append(tag)
 

-        book.tags = book_tags + book_shelves
+        book.tags = set(book_tags + book_shelves)

 
         book_tag = book.book_tag()
 
 
         book_tag = book.book_tag()
 


@@ -582,8 +675,11 @@ class Book(models.Model):
                 new_fragment.save()
                 new_fragment.tags = set(book_tags + themes + [book_tag] + ancestor_tags)
 
                 new_fragment.save()
                 new_fragment.tags = set(book_tags + themes + [book_tag] + ancestor_tags)
 

-        if not settings.NO_BUILD_EPUB:
-            book.root_ancestor().build_epub()
+            if not settings.NO_BUILD_TXT and build_txt:
+                book.build_txt()
+
+        if not settings.NO_BUILD_EPUB and build_epub:
+            book.root_ancestor.build_epub()

 
         book_descendants = list(book.children.all())
         # add l-tag to descendants and their fragments
 
         book_descendants = list(book.children.all())
         # add l-tag to descendants and their fragments


@@ -612,12 +708,12 @@ class Book(models.Model):
         for tag in self.tags.exclude(category__in=('book', 'theme', 'set')).order_by():
             tags[tag.pk] = 1
         self.set__tag_counter_value(tags)
         for tag in self.tags.exclude(category__in=('book', 'theme', 'set')).order_by():
             tags[tag.pk] = 1
         self.set__tag_counter_value(tags)

-        self.save(reset_short_html=False, refresh_mp3=False)
+        self.save(reset_short_html=False)

         return tags
 
     def reset_tag_counter(self):
         self._tag_counter = None
         return tags
 
     def reset_tag_counter(self):
         self._tag_counter = None

-        self.save(reset_short_html=False, refresh_mp3=False)
+        self.save(reset_short_html=False)

         if self.parent:
             self.parent.reset_tag_counter()
 
         if self.parent:
             self.parent.reset_tag_counter()
 


@@ -633,12 +729,12 @@ class Book(models.Model):
             for tag in fragment.tags.filter(category='theme').order_by():
                 tags[tag.pk] = tags.get(tag.pk, 0) + 1
         self.set__theme_counter_value(tags)
             for tag in fragment.tags.filter(category='theme').order_by():
                 tags[tag.pk] = tags.get(tag.pk, 0) + 1
         self.set__theme_counter_value(tags)

-        self.save(reset_short_html=False, refresh_mp3=False)
+        self.save(reset_short_html=False)

         return tags
 
     def reset_theme_counter(self):
         self._theme_counter = None
         return tags
 
     def reset_theme_counter(self):
         self._theme_counter = None

-        self.save(reset_short_html=False, refresh_mp3=False)
+        self.save(reset_short_html=False)

         if self.parent:
             self.parent.reset_theme_counter()
 
         if self.parent:
             self.parent.reset_theme_counter()
 


@@ -665,6 +761,24 @@ class Book(models.Model):
 
         return ', '.join(names)
 
 
         return ', '.join(names)
 

+    @classmethod
+    def tagged_top_level(cls, tags):
+        """ Returns top-level books tagged with `tags'.
+
+        It only returns those books which don't have ancestors which are
+        also tagged with those tags.
+
+        """
+        # get relevant books and their tags
+        objects = cls.tagged.with_all(tags)
+        # eliminate descendants
+        l_tags = Tag.objects.filter(category='book', slug__in=[book.book_tag_slug() for book in objects])
+        descendants_keys = [book.pk for book in cls.tagged.with_any(l_tags)]
+        if descendants_keys:
+            objects = objects.exclude(pk__in=descendants_keys)
+
+        return objects
+

 
 class Fragment(models.Model):
     text = models.TextField()
 
 class Fragment(models.Model):
     text = models.TextField()


@@ -711,10 +825,17 @@ class FileRecord(models.Model):
     def __unicode__(self):
         return "%s %s.%s" % (self.sha1,  self.slug, self.type)
 
     def __unicode__(self):
         return "%s %s.%s" % (self.sha1,  self.slug, self.type)
 

+###########
+#
+# SIGNALS
+#
+###########
+

 
 def _tags_updated_handler(sender, affected_tags, **kwargs):
     # reset tag global counter
 
 def _tags_updated_handler(sender, affected_tags, **kwargs):
     # reset tag global counter

-    Tag.objects.filter(pk__in=[tag.pk for tag in affected_tags]).update(book_count=None)
+    # we want Tag.changed_at updated for API to know the tag was touched
+    Tag.objects.filter(pk__in=[tag.pk for tag in affected_tags]).update(book_count=None, changed_at=datetime.now())

 
     # if book tags changed, reset book tag counter
     if isinstance(sender, Book) and \
 
     # if book tags changed, reset book tag counter
     if isinstance(sender, Book) and \


@@ -728,3 +849,15 @@ def _tags_updated_handler(sender, affected_tags, **kwargs):
         sender.book.reset_theme_counter()
 tags_updated.connect(_tags_updated_handler)
 
         sender.book.reset_theme_counter()
 tags_updated.connect(_tags_updated_handler)
 

+
+def _pre_delete_handler(sender, instance, **kwargs):
+    """ refresh Book on BookMedia delete """
+    if sender == BookMedia:
+        instance.book.save()
+pre_delete.connect(_pre_delete_handler)
+
+def _post_save_handler(sender, instance, **kwargs):
+    """ refresh all the short_html stuff on BookMedia update """
+    if sender == BookMedia:
+        instance.book.save()
+post_save.connect(_post_save_handler)