Using cache middleware instead of various caching micro-strategies,
[wolnelektury.git] / apps / lesmianator / models.py
index 74aecfe..5db02c2 100644 (file)
@@ -9,24 +9,22 @@ from StringIO import StringIO
 
 from django.core.files.base import ContentFile
 from django.db import models
-from django.db.models import permalink
+from django.utils.timezone import utc
 from django.utils.translation import ugettext_lazy as _
 from django.core.urlresolvers import reverse
-from django.db.models.signals import m2m_changed
 from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
-from django.contrib.contenttypes import generic
+from django.contrib.contenttypes.fields import GenericForeignKey
 from django.conf import settings
 
-from librarian import text
-from catalogue.fields import JSONField
+from jsonfield import JSONField
 from catalogue.models import Book, Tag
 
 
 class Poem(models.Model):
     slug = models.SlugField(_('slug'), max_length=120, db_index=True)
     text = models.TextField(_('text'))
-    created_by = models.ForeignKey(User)
+    created_by = models.ForeignKey(User, null=True)
     created_from = JSONField(_('extra information'), null=True, blank=True)
     created_at = models.DateTimeField(_('creation date'), auto_now_add=True, editable=False)
     seen_at = models.DateTimeField(_('last view date'), auto_now_add=True, editable=False)
@@ -41,52 +39,59 @@ class Poem(models.Model):
 
     def visit(self):
         self.view_count += 1
-        self.seen_at = datetime.now()
+        self.seen_at = datetime.utcnow().replace(tzinfo=utc)
         self.save()
 
     def __unicode__(self):
         return "%s (%s...)" % (self.slug, self.text[:20])
 
-    @classmethod
-    def write(cls, continuations=None, length=3, maxlen=1000):
-        def choose_word(word, continuations):
-            try:
-                choices = sum((continuations[word][post] for post in continuations[word]))
-                r = randint(0, choices - 1)
+    @staticmethod
+    def choose_letter(word, continuations):
+        if word not in continuations:
+            return u'\n'
 
-                for post in continuations[word]:
-                    r -= continuations[word][post]
-                    if r < 0:
-                        return post
-            except KeyError:
-                return ''
+        choices = sum((continuations[word][letter]
+                       for letter in continuations[word]))
+        r = randint(0, choices - 1)
 
+        for letter in continuations[word]:
+            r -= continuations[word][letter]
+            if r < 0:
+                return letter
 
+    @classmethod
+    def write(cls, continuations=None, length=3, min_lines=2, maxlen=1000):
         if continuations is None:
             continuations = cls.global_dictionary
+        if not continuations:
+            return ''
 
         letters = []
         word = u''
-        empty = -10
-        lines = 0
-        if not continuations:
-            maxlen = 0
-        # want at least two lines, but let Lesmianator end his stanzas
-        while (empty < 2 or lines < 2) and maxlen:
-            letter = choose_word(word, continuations)
+
+        finished_stanza_verses = 0
+        current_stanza_verses = 0
+        verse_start = True
+
+        char_count = 0
+
+        # do `min_lines' non-empty verses and then stop,
+        # but let Lesmianator finish his last stanza.
+        while finished_stanza_verses < min_lines and char_count < maxlen:
+            letter = cls.choose_letter(word, continuations)
             letters.append(letter)
-            word = word[-length+1:] + letter
+            word = word[-length + 1:] + letter
+            char_count += 1
+
             if letter == u'\n':
-                # count non-empty lines
-                if empty == 0:
-                    lines += 1
-                # 
-                if lines >= 2:
-                    empty += 1
-                lines += 1
+                if verse_start:
+                    finished_stanza_verses += current_stanza_verses
+                    current_stanza_verses = 0
+                else:
+                    current_stanza_verses += 1
+                    verse_start = True
             else:
-                empty = 0
-            maxlen -= 1
+                verse_start = False
 
         return ''.join(letters).strip()
 
@@ -98,7 +103,10 @@ class Continuations(models.Model):
     pickle = models.FileField(_('Continuations file'), upload_to='lesmianator')
     content_type = models.ForeignKey(ContentType)
     object_id = models.PositiveIntegerField()
-    content_object = generic.GenericForeignKey('content_type', 'object_id')
+    content_object = GenericForeignKey('content_type', 'object_id')
+
+    class Meta:
+        unique_together = (('content_type', 'object_id'), )
 
     def __unicode__(self):
         return "Continuations for: %s" % unicode(self.content_object)
@@ -115,33 +123,27 @@ class Continuations(models.Model):
     @classmethod
     def for_book(cls, book, length=3):
         # count from this book only
-        print 'for_book', book
         output = StringIO()
-        f = open(book.xml_file.path)
-        text.transform(f, output, False, ('raw-text',))
-        f.close()
+        wldoc = book.wldocument(parse_dublincore=False)
+        output = wldoc.as_text(('raw-text',)).get_string()
+        del wldoc
+
         conts = {}
         last_word = ''
-        for letter in output.getvalue().decode('utf-8').strip().lower():
+        for letter in output.decode('utf-8').strip().lower():
             mydict = conts.setdefault(last_word, {})
             mydict.setdefault(letter, 0)
             mydict[letter] += 1
             last_word = last_word[-length+1:] + letter
         # add children
-        return reduce(cls.join_conts, 
-                      (cls.get(child) for child in book.children.all()),
+        return reduce(cls.join_conts,
+                      (cls.get(child) for child in book.children.all().iterator()),
                       conts)
 
     @classmethod
     def for_set(cls, tag):
-        # book contains its descendants, we don't want them twice
-        books = Book.tagged.with_any((tag,))
-        l_tags = Tag.objects.filter(category='book', slug__in=[book.book_tag_slug() for book in books])
-        descendants_keys = [book.pk for book in Book.tagged.with_any(l_tags)]
-        if descendants_keys:
-            books = books.exclude(pk__in=descendants_keys)
-
-        cont_tabs = (cls.get(b) for b in books)
+        books = Book.tagged_top_level([tag])
+        cont_tabs = (cls.get(b) for b in books.iterator())
         return reduce(cls.join_conts, cont_tabs)
 
     @classmethod
@@ -149,14 +151,15 @@ class Continuations(models.Model):
         object_type = ContentType.objects.get_for_model(sth)
         should_keys = set([sth.id])
         if isinstance(sth, Tag):
-            should_keys = set(b.pk for b in Book.tagged.with_any((sth,)))
+            should_keys = set(b.pk for b in Book.tagged.with_any((sth,)).iterator())
         try:
             obj = cls.objects.get(content_type=object_type, object_id=sth.id)
+            if not obj.pickle:
+                raise cls.DoesNotExist
             f = open(obj.pickle.path)
             keys, conts = cPickle.load(f)
             f.close()
             if set(keys) != should_keys:
-                obj.delete()
                 raise cls.DoesNotExist
             return conts
         except cls.DoesNotExist:
@@ -165,9 +168,9 @@ class Continuations(models.Model):
             elif isinstance(sth, Tag):
                 conts = cls.for_set(sth)
             else:
-                raise NotImplemented('Lesmianator continuations: only Book and Tag supported')
+                raise NotImplementedError('Lesmianator continuations: only Book and Tag supported')
 
-            c = cls(content_object=sth)
+            c, created = cls.objects.get_or_create(content_type=object_type, object_id=sth.id)
             c.pickle.save(sth.slug+'.p', ContentFile(cPickle.dumps((should_keys, conts))))
             c.save()
             return conts