Locale.
[wolnelektury.git] / src / search / index.py
index 31417ca..2d84cb4 100644 (file)
@@ -1,27 +1,34 @@
-# -*- coding: utf-8 -*-
 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 #
-from django.conf import settings
-
+from functools import reduce, total_ordering
+from itertools import chain
+import logging
+import operator
 import os
 import re
-import errno
+from django.conf import settings
 from librarian import dcparser
 from librarian.parser import WLDocument
 from lxml import etree
+import scorched
 import catalogue.models
+import picture.models
 from pdcounter.models import Author as PDCounterAuthor, BookStub as PDCounterBook
-from itertools import chain
-import traceback
-import logging
-log = logging.getLogger('search')
-import sunburnt
-import custom
-import operator
+from wolnelektury.utils import makedirs
+from . import custom
 
 log = logging.getLogger('search')
 
+
+if os.path.isfile(settings.SOLR_STOPWORDS):
+    stopwords = set(
+        line.strip()
+        for line in open(settings.SOLR_STOPWORDS) if not line.startswith('#'))
+else:
+    stopwords = set()
+
+
 class SolrIndex(object):
     def __init__(self, mode=None):
         self.index = custom.CustomSolrInterface(settings.SOLR, mode=mode)
@@ -36,20 +43,18 @@ class Snippets(object):
     SNIPPET_DIR = "snippets"
 
     def __init__(self, book_id, revision=None):
-        try:
-            os.makedirs(os.path.join(settings.SEARCH_INDEX, self.SNIPPET_DIR))
-        except OSError as exc:
-            if exc.errno == errno.EEXIST:
-                pass
-            else: raise
+        makedirs(os.path.join(settings.SEARCH_INDEX, self.SNIPPET_DIR))
         self.book_id = book_id
         self.revision = revision
         self.file = None
+        self.position = None
 
     @property
     def path(self):
-        if self.revision: fn = "%d.%d" % (self.book_id, self.revision)
-        else: fn = "%d" % self.book_id
+        if self.revision:
+            fn = "%d.%d" % (self.book_id, self.revision)
+        else:
+            fn = "%d" % self.book_id
 
         return os.path.join(settings.SEARCH_INDEX, self.SNIPPET_DIR, fn)
 
@@ -57,7 +62,7 @@ class Snippets(object):
         """
         Open the snippet file. Call .close() afterwards.
         """
-        if not 'b' in mode:
+        if 'b' not in mode:
             mode += 'b'
 
         if 'w' in mode:
@@ -124,7 +129,7 @@ class Index(SolrIndex):
         """
         uids = set()
         for q in queries:
-            if isinstance(q, sunburnt.search.LuceneQuery):
+            if isinstance(q, scorched.search.LuceneQuery):
                 q = self.index.query(q)
             q.field_limiter.update(['uid'])
             st = 0
@@ -137,7 +142,8 @@ class Index(SolrIndex):
                     uids.add(res['uid'])
                 st += rows
         if uids:
-            self.index.delete(uids)
+            # FIXME: With Solr API change, this doesn't work.
+            #self.index.delete(uids)
             return True
         else:
             return False
@@ -173,8 +179,9 @@ class Index(SolrIndex):
         if not remove_only:
             # then add them [all or just one passed]
             if not tags:
-                tags = chain(catalogue.models.Tag.objects.exclude(category='set'), \
-                    PDCounterAuthor.objects.all(), \
+                tags = chain(
+                    catalogue.models.Tag.objects.exclude(category='set'),
+                    PDCounterAuthor.objects.all(),
                     PDCounterBook.objects.all())
 
             for tag in tags:
@@ -211,11 +218,9 @@ class Index(SolrIndex):
         """
         Create a lucene document referring book id.
         """
-        doc = {
-            'book_id': int(book.id),
-            }
+        doc = {'book_id': int(book.id)}
         if book.parent is not None:
-            doc["parent_id"] = int(book.parent.id)
+            doc['parent_id'] = int(book.parent.id)
         return doc
 
     def remove_book(self, book_or_id, remove_snippets=True):
@@ -244,7 +249,8 @@ class Index(SolrIndex):
             self.remove_book(book, remove_snippets=False)
 
         book_doc = self.create_book_doc(book)
-        meta_fields = self.extract_metadata(book, book_info, dc_only=['source_name', 'authors', 'translators', 'title'])
+        meta_fields = self.extract_metadata(book, book_info, dc_only=[
+            'source_name', 'authors', 'translators', 'title', 'epochs', 'kinds', 'genres'])
         # let's not index it - it's only used for extracting publish date
         if 'source_name' in meta_fields:
             del meta_fields['source_name']
@@ -261,8 +267,9 @@ class Index(SolrIndex):
             'published_date': meta_fields['published_date']
             }
 
-        if 'translators' in meta_fields:
-            book_fields['translators'] = meta_fields['translators']
+        for tag_name in ('translators', 'epochs', 'kinds', 'genres'):
+            if tag_name in meta_fields:
+                book_fields[tag_name] = meta_fields[tag_name]
 
         self.index_content(book, book_fields=book_fields)
 
@@ -273,18 +280,19 @@ class Index(SolrIndex):
         'dramat_wierszowany_lp',
         'dramat_wspolczesny', 'liryka_l', 'liryka_lp',
         'wywiad',
-        ]
+    ]
 
     ignore_content_tags = [
-        'uwaga', 'extra',
+        'uwaga', 'extra', 'nota_red', 'abstrakt',
         'zastepnik_tekstu', 'sekcja_asterysk', 'separator_linia', 'zastepnik_wersu',
         'didaskalia',
         'naglowek_aktu', 'naglowek_sceny', 'naglowek_czesc',
-        ]
+    ]
 
     footnote_tags = ['pa', 'pt', 'pr', 'pe']
 
-    skip_header_tags = ['autor_utworu', 'nazwa_utworu', 'dzielo_nadrzedne', '{http://www.w3.org/1999/02/22-rdf-syntax-ns#}RDF']
+    skip_header_tags = ['autor_utworu', 'nazwa_utworu', 'dzielo_nadrzedne',
+                        '{http://www.w3.org/1999/02/22-rdf-syntax-ns#}RDF']
 
     published_date_re = re.compile("([0-9]+)[\]. ]*$")
 
@@ -298,7 +306,6 @@ class Index(SolrIndex):
             book_info = dcparser.parse(open(book.xml_file.path))
 
         fields['slug'] = book.slug
-        fields['tags'] = [t.name  for t in book.tags]
         fields['is_book'] = True
 
         # validator, name
@@ -318,9 +325,9 @@ class Index(SolrIndex):
                 elif type_indicator == dcparser.as_person:
                     p = getattr(book_info, field.name)
                     if isinstance(p, dcparser.Person):
-                        persons = unicode(p)
+                        persons = str(p)
                     else:
-                        persons = ', '.join(map(unicode, p))
+                        persons = ', '.join(map(str, p))
                     fields[field.name] = persons
                 elif type_indicator == dcparser.as_date:
                     dt = getattr(book_info, field.name)
@@ -332,7 +339,8 @@ class Index(SolrIndex):
             match = self.published_date_re.search(book_info.source_name)
             if match is not None:
                 pd = str(match.groups()[0])
-        if not pd: pd = ""
+        if not pd:
+            pd = ""
         fields["published_date"] = pd
 
         return fields
@@ -355,7 +363,7 @@ class Index(SolrIndex):
             if master.tag in self.master_tags:
                 return master
 
-    def index_content(self, book, book_fields={}):
+    def index_content(self, book, book_fields):
         """
         Walks the book XML and extract content from it.
         Adds parts for each header tag and for each fragment.
@@ -367,9 +375,8 @@ class Index(SolrIndex):
         if master is None:
             return []
 
-        def walker(node, ignore_tags=[]):
-
-            if node.tag not in ignore_tags:
+        def walker(node):
+            if node.tag not in self.ignore_content_tags:
                 yield node, None, None
                 if node.text is not None:
                     yield None, node.text, None
@@ -383,16 +390,16 @@ class Index(SolrIndex):
             return
 
         def fix_format(text):
-            #            separator = [u" ", u"\t", u".", u";", u","]
+            # separator = [" ", "\t", ".", ";", ","]
             if isinstance(text, list):
                 # need to join it first
                 text = filter(lambda s: s is not None, content)
-                text = u' '.join(text)
+                text = ' '.join(text)
                 # for i in range(len(text)):
                 #     if i > 0:
                 #         if text[i][0] not in separator\
                 #             and text[i - 1][-1] not in separator:
-                #          text.insert(i, u" ")
+                #          text.insert(i, " ")
 
             return re.sub("(?m)/$", "", text)
 
@@ -420,17 +427,10 @@ class Index(SolrIndex):
 
             if 'themes' in fields:
                 doc['themes'] = fields['themes']
-            doc['uid'] = "part%s%s%s" % (doc['header_index'],
-                                         doc['header_span'],
-                                         doc.get('fragment_anchor', ''))
+            doc['uid'] = "part%s-%s-%s-%s" % (
+                book.id, doc['header_index'], doc['header_span'], doc.get('fragment_anchor', ''))
             return doc
 
-        def give_me_utf8(s):
-            if isinstance(s, unicode):
-                return s.encode('utf-8')
-            else:
-                return s
-
         fragments = {}
         snippets = Snippets(book.id).open('w')
         try:
@@ -451,7 +451,7 @@ class Index(SolrIndex):
                     content.append(text)
                 handle_text = [all_content]
 
-                for start, text, end in walker(header, ignore_tags=self.ignore_content_tags):
+                for start, text, end in walker(header):
                     # handle footnotes
                     if start is not None and start.tag in self.footnote_tags:
                         footnote = []
@@ -463,7 +463,7 @@ class Index(SolrIndex):
                     elif end is not None and footnote is not [] and end.tag in self.footnote_tags:
                         handle_text.pop()
                         doc = add_part(snippets, header_index=position, header_type=header.tag,
-                                       text=u''.join(footnote),
+                                       text=''.join(footnote),
                                        is_footnote=True)
                         self.index.add(doc)
                         footnote = []
@@ -471,14 +471,15 @@ class Index(SolrIndex):
                     # handle fragments and themes.
                     if start is not None and start.tag == 'begin':
                         fid = start.attrib['id'][1:]
-                        fragments[fid] = {'text': [], 'themes': [], 'start_section': position, 'start_header': header.tag}
+                        fragments[fid] = {
+                            'text': [], 'themes': [], 'start_section': position, 'start_header': header.tag}
 
                     # themes for this fragment
                     elif start is not None and start.tag == 'motyw':
                         fid = start.attrib['id'][1:]
-                        handle_text.append(None)
+                        handle_text.append(lambda text: None)
                         if start.text is not None:
-                            fragments[fid]['themes'] += map(unicode.strip, map(unicode, (start.text.split(','))))
+                            fragments[fid]['themes'] += map(str.strip, map(str, (start.text.split(','))))
                     elif end is not None and end.tag == 'motyw':
                         handle_text.pop()
 
@@ -487,7 +488,7 @@ class Index(SolrIndex):
                         if fid not in fragments:
                             continue  # a broken <end> node, skip it
                         frag = fragments[fid]
-                        if frag['themes'] == []:
+                        if not frag['themes']:
                             continue  # empty themes list.
                         del fragments[fid]
 
@@ -504,8 +505,7 @@ class Index(SolrIndex):
 
                     if text is not None and handle_text is not []:
                         hdl = handle_text[-1]
-                        if hdl is not None:
-                            hdl(text)
+                        hdl(text)
 
                         # in the end, add a section text.
                 doc = add_part(snippets, header_index=position,
@@ -516,15 +516,57 @@ class Index(SolrIndex):
         finally:
             snippets.close()
 
+    def remove_picture(self, picture_or_id):
+        """Removes a picture from search index."""
+        if isinstance(picture_or_id, picture.models.Picture):
+            picture_id = picture_or_id.id
+        else:
+            picture_id = picture_or_id
+        self.delete_query(self.index.Q(picture_id=picture_id))
+
+    def index_picture(self, picture, picture_info=None, overwrite=True):
+        """
+        Indexes the picture.
+        Creates a lucene document for extracted metadata
+        and calls self.index_area() to index the contents of the picture.
+        """
+        if overwrite:
+            # we don't remove snippets, since they might be still needed by
+            # threads using not reopened index
+            self.remove_picture(picture)
+
+        picture_doc = {'picture_id': int(picture.id)}
+        meta_fields = self.extract_metadata(picture, picture_info, dc_only=[
+            'authors', 'title', 'epochs', 'kinds', 'genres'])
+
+        picture_doc.update(meta_fields)
 
+        picture_doc['uid'] = "picture%s" % picture_doc['picture_id']
+        self.index.add(picture_doc)
+        del picture_doc['is_book']
+        for area in picture.areas.all():
+            self.index_area(area, picture_fields=picture_doc)
+
+    def index_area(self, area, picture_fields):
+        """
+        Indexes themes and objects on the area.
+        """
+        doc = dict(picture_fields)
+        doc['area_id'] = area.id
+        doc['themes'] = list(area.tags.filter(category__in=('theme', 'thing')).values_list('name', flat=True))
+        doc['uid'] = 'area%s' % area.id
+        self.index.add(doc)
+
+
+@total_ordering
 class SearchResult(object):
-    def __init__(self, doc, how_found=None, query=None, query_terms=None):
-        #        self.search = search
+    def __init__(self, doc, how_found=None, query_terms=None):
         self.boost = 1.0
         self._hits = []
         self._processed_hits = None  # processed hits
         self.snippets = []
         self.query_terms = query_terms
+        self._book = None
 
         if 'score' in doc:
             self._score = doc['score']
@@ -559,12 +601,25 @@ class SearchResult(object):
 
             self._hits.append(hit)
 
-    def __unicode__(self):
-        return u"<SR id=%d %d(%d) hits score=%f %d snippets>" % \
-            (self.book_id, len(self._hits), self._processed_hits and len(self._processed_hits) or -1, self._score, len(self.snippets))
+    @classmethod
+    def from_book(cls, book, how_found=None, query_terms=None):
+        doc = {
+            'score': book.popularity.count,
+            'book_id': book.id,
+            'published_date': 0,
+        }
+        result = cls(doc, how_found=how_found, query_terms=query_terms)
+        result._book = book
+        return result
 
     def __str__(self):
-        return unicode(self).encode('utf-8')
+        return "<SR id=%d %d(%d) hits score=%f %d snippets>" % \
+            (self.book_id, len(self._hits),
+             len(self._processed_hits) if self._processed_hits else -1,
+             self._score, len(self.snippets))
+
+    def __bytes__(self):
+        return str(self).encode('utf-8')
 
     @property
     def score(self):
@@ -572,16 +627,18 @@ class SearchResult(object):
 
     def merge(self, other):
         if self.book_id != other.book_id:
-            raise ValueError("this search result is or book %d; tried to merge with %d" % (self.book_id, other.book_id))
+            raise ValueError("this search result is for book %d; tried to merge with %d" % (self.book_id, other.book_id))
         self._hits += other._hits
-        if other.score > self.score:
-            self._score = other._score
+        self._score += max(other._score, 0)
         return self
 
     def get_book(self):
-        if hasattr(self, '_book'):
+        if self._book is not None:
             return self._book
-        self._book = catalogue.models.Book.objects.get(id=self.book_id)
+        try:
+            self._book = catalogue.models.Book.objects.get(id=self.book_id)
+        except catalogue.models.Book.DoesNotExist:
+            self._book = None
         return self._book
 
     book = property(get_book)
@@ -601,30 +658,25 @@ class SearchResult(object):
         # to sections and fragments
         frags = filter(lambda r: r[self.FRAGMENT] is not None, self._hits)
 
-        sect = filter(lambda r: r[self.FRAGMENT] is None, self._hits)
+        sect = [hit for hit in self._hits if hit[self.FRAGMENT] is None]
 
         # sections not covered by fragments
-        sect = filter(lambda s: 0 == len(filter(
-            lambda f: s[self.POSITION][self.POSITION_INDEX] >= f[self.POSITION][self.POSITION_INDEX]
-            and s[self.POSITION][self.POSITION_INDEX] < f[self.POSITION][self.POSITION_INDEX] + f[self.POSITION][self.POSITION_SPAN],
-            frags)), sect)
+        sect = filter(lambda s: 0 == len(list(filter(
+            lambda f: f[self.POSITION][self.POSITION_INDEX] <= s[self.POSITION][self.POSITION_INDEX] <
+                      f[self.POSITION][self.POSITION_INDEX] + f[self.POSITION][self.POSITION_SPAN], frags))), sect)
 
-        hits = []
-
-        def remove_duplicates(lst, keyfn, compare):
+        def remove_duplicates(lst, keyfn, larger):
             els = {}
             for e in lst:
                 eif = keyfn(e)
                 if eif in els:
-                    if compare(els[eif], e) >= 1:
+                    if larger(els[eif], e):
                         continue
                 els[eif] = e
             return els.values()
 
         # remove fragments with duplicated fid's and duplicated snippets
-        frags = remove_duplicates(frags, lambda f: f[self.FRAGMENT], lambda a, b: cmp(a[self.SCORE], b[self.SCORE]))
-        # frags = remove_duplicates(frags, lambda f: f[OTHER]['snippet_pos'] and f[OTHER]['snippet_pos'] or f[FRAGMENT],
-        #                           lambda a, b: cmp(a[SCORE], b[SCORE]))
+        frags = remove_duplicates(frags, lambda f: f[self.FRAGMENT], lambda a, b: a[self.SCORE] > b[self.SCORE])
 
         # remove duplicate sections
         sections = {}
@@ -642,7 +694,7 @@ class SearchResult(object):
             m.update(s[self.OTHER])
             sections[si] = m
 
-        hits = sections.values()
+        hits = list(sections.values())
 
         for f in frags:
             try:
@@ -656,19 +708,19 @@ class SearchResult(object):
             if self.query_terms is not None:
                 for i in range(0, len(f[self.OTHER]['themes'])):
                     tms = f[self.OTHER]['themes'][i].split(r' +') + f[self.OTHER]['themes_pl'][i].split(' ')
-                    tms = map(unicode.lower, tms)
+                    tms = map(str.lower, tms)
                     for qt in self.query_terms:
                         if qt in tms:
                             themes_hit.add(f[self.OTHER]['themes'][i])
                             break
 
             def theme_by_name(n):
-                th = filter(lambda t: t.name == n, themes)
+                th = list(filter(lambda t: t.name == n, themes))
                 if th:
                     return th[0]
                 else:
                     return None
-            themes_hit = filter(lambda a: a is not None, map(theme_by_name, themes_hit))
+            themes_hit = list(filter(lambda a: a is not None, map(theme_by_name, themes_hit)))
 
             m = {'score': f[self.SCORE],
                  'fragment': frag,
@@ -679,7 +731,7 @@ class SearchResult(object):
             m.update(f[self.OTHER])
             hits.append(m)
 
-        hits.sort(lambda a, b: cmp(a['score'], b['score']), reverse=True)
+        hits.sort(key=lambda h: h['score'], reverse=True)
 
         self._processed_hits = hits
 
@@ -696,13 +748,17 @@ class SearchResult(object):
                     books[r.book_id] = r
         return books.values()
 
-    def __cmp__(self, other):
-        c = cmp(self.score, other.score)
-        if c == 0:
-            # this is inverted, because earlier date is better
-            return cmp(other.published_date, self.published_date)
-        else:
-            return c
+    def get_sort_key(self):
+        return (-self.score,
+                self.published_date,
+                self.book.sort_key_author if self.book else '',
+                self.book.sort_key if self.book else '')
+
+    def __lt__(self, other):
+        return self.get_sort_key() > other.get_sort_key()
+
+    def __eq__(self, other):
+        return self.get_sort_key() == other.get_sort_key()
 
     def __len__(self):
         return len(self.hits)
@@ -713,93 +769,183 @@ class SearchResult(object):
     def snippet_revision(self, idx=0):
         try:
             return self.hits[idx]['snippets_revision']
-        except:
+        except (IndexError, KeyError):
             return None
 
 
-class Search(SolrIndex):
-    """
-    Search facilities.
-    """
-    def __init__(self, default_field="text"):
-        super(Search, self).__init__(mode='r')
+@total_ordering
+class PictureResult(object):
+    def __init__(self, doc, how_found=None, query_terms=None):
+        self.boost = 1.0
+        self.query_terms = query_terms
+        self._picture = None
+        self._hits = []
+        self._processed_hits = None
 
+        if 'score' in doc:
+            self._score = doc['score']
+        else:
+            self._score = 0
 
-    def make_term_query(self, query, field='text', modal=operator.or_):
-        """
-        Returns term queries joined by boolean query.
-        modal - applies to boolean query
-        fuzzy - should the query by fuzzy.
-        """
-        if query is None: query = ''
-        q = self.index.Q()
-        q = reduce(modal, map(lambda s: self.index.Q(**{field: s}),
-                        query.split(r" ")), q)
+        self.picture_id = int(doc["picture_id"])
 
-        return q
+        if doc.get('area_id'):
+            hit = (self._score, {
+                'how_found': how_found,
+                'area_id': doc['area_id'],
+                'themes': doc.get('themes', []),
+                'themes_pl': doc.get('themes_pl', []),
+            })
 
-    def search_phrase(self, searched, field='text', book=False,
-                      filters=None,
-                      snippets=False):
-        if filters is None: filters = []
-        if book: filters.append(self.index.Q(is_book=True))
+            self._hits.append(hit)
 
-        q = self.index.query(**{field: searched})
-        q = self.apply_filters(q, filters).field_limit(score=True, all_fields=True)
-        res = q.execute()
-        return [SearchResult(found, how_found=u'search_phrase') for found in res]
+    def __str__(self):
+        return "<PR id=%d score=%f >" % (self.picture_id, self._score)
 
-    def search_some(self, searched, fields, book=True,
-                    filters=None, snippets=True, query_terms=None):
-        assert isinstance(fields, list)
-        if filters is None: filters = []
-        if book: filters.append(self.index.Q(is_book=True))
+    def __repr__(self):
+        return str(self)
 
-        query = self.index.Q()
+    @property
+    def score(self):
+        return self._score * self.boost
 
-        for fld in fields:
-            query = self.index.Q(query | self.make_term_query(searched, fld))
+    def merge(self, other):
+        if self.picture_id != other.picture_id:
+            raise ValueError(
+                "this search result is for picture %d; tried to merge with %d" % (self.picture_id, other.picture_id))
+        self._hits += other._hits
+        self._score += max(other._score, 0)
+        return self
 
-        query = self.index.query(query)
-        query = self.apply_filters(query, filters).field_limit(score=True, all_fields=True)
-        res = query.execute()
-        return [SearchResult(found, how_found='search_some', query_terms=query_terms) for found in res]
+    SCORE = 0
+    OTHER = 1
 
+    @property
+    def hits(self):
+        if self._processed_hits is not None:
+            return self._processed_hits
 
-    def search_everywhere(self, searched, query_terms=None):
-        """
-        Tries to use search terms to match different fields of book (or its parts).
-        E.g. one word can be an author survey, another be a part of the title, and the rest
-        are some words from third chapter.
-        """
-        books = []
-        # content only query : themes x content
-        q = self.make_term_query(searched, 'text')
-        q_themes = self.make_term_query(searched, 'themes_pl')
+        hits = []
+        for hit in self._hits:
+            try:
+                area = picture.models.PictureArea.objects.get(id=hit[self.OTHER]['area_id'])
+            except picture.models.PictureArea.DoesNotExist:
+                # stale index
+                continue
+            # Figure out if we were searching for a token matching some word in theme name.
+            themes_hit = set()
+            if self.query_terms is not None:
+                for i in range(0, len(hit[self.OTHER]['themes'])):
+                    tms = hit[self.OTHER]['themes'][i].split(r' +') + hit[self.OTHER]['themes_pl'][i].split(' ')
+                    tms = map(str.lower, tms)
+                    for qt in self.query_terms:
+                        if qt in tms:
+                            themes_hit.add(hit[self.OTHER]['themes'][i])
+                            break
 
-        query = self.index.query(q).query(q_themes).field_limit(score=True, all_fields=True)
-        res = query.execute()
+            m = {
+                'score': hit[self.SCORE],
+                'area': area,
+                'themes_hit': themes_hit,
+            }
+            m.update(hit[self.OTHER])
+            hits.append(m)
 
-        for found in res:
-            books.append(SearchResult(found, how_found='search_everywhere_themesXcontent', query_terms=query_terms))
+        hits.sort(key=lambda h: h['score'], reverse=True)
+        hits = hits[:1]
+        self._processed_hits = hits
+        return hits
 
-        # query themes/content x author/title/tags
-        in_content = self.index.Q()
-        in_meta = self.index.Q()
+    def get_picture(self):
+        if self._picture is None:
+            self._picture = picture.models.Picture.objects.get(id=self.picture_id)
+        return self._picture
 
-        for fld in ['themes_pl', 'text']:
-            in_content |= self.make_term_query(searched, field=fld)
+    picture = property(get_picture)
 
-        for fld in ['tags', 'authors', 'title']:
-            in_meta |= self.make_term_query(searched, field=fld)
+    @staticmethod
+    def aggregate(*result_lists):
+        books = {}
+        for rl in result_lists:
+            for r in rl:
+                if r.picture_id in books:
+                    books[r.picture_id].merge(r)
+                else:
+                    books[r.picture_id] = r
+        return books.values()
+
+    def __lt__(self, other):
+        return self.score < other.score
+
+    def __eq__(self, other):
+        return self.score == other.score
 
-        q = in_content & in_meta
-        res = self.index.query(q).field_limit(score=True, all_fields=True).execute()
 
-        for found in res:
-            books.append(SearchResult(found, how_found='search_everywhere', query_terms=query_terms))
+class Search(SolrIndex):
+    """
+    Search facilities.
+    """
+    def __init__(self, default_field="text"):
+        super(Search, self).__init__(mode='r')
+
+    def make_term_query(self, query, field='text', modal=operator.or_):
+        """
+        Returns term queries joined by boolean query.
+        modal - applies to boolean query
+        fuzzy - should the query by fuzzy.
+        """
+        if query is None:
+            query = ''
+        q = self.index.Q()
+        q = reduce(modal, map(lambda s: self.index.Q(**{field: s}), query.split(r" ")), q)
+
+        return q
 
-        return books
+    def search_by_author(self, words):
+        from catalogue.models import Book
+        books = Book.objects.filter(parent=None).order_by('-popularity__count')
+        for word in words:
+            books = books.filter(cached_author__iregex='\m%s\M' % word).select_related('popularity__count')
+        return [SearchResult.from_book(book, how_found='search_by_author', query_terms=words) for book in books[:30]]
+
+    def search_words(self, words, fields, required=None, book=True, picture=False):
+        if book and not picture and fields == ['authors']:
+            return self.search_by_author(words)
+        filters = []
+        for word in words:
+            if book or picture or (word not in stopwords):
+                word_filter = None
+                for field in fields:
+                    q = self.index.Q(**{field: word})
+                    if word_filter is None:
+                        word_filter = q
+                    else:
+                        word_filter |= q
+                filters.append(word_filter)
+        if required:
+            required_filter = None
+            for field in required:
+                for word in words:
+                    if book or picture or (word not in stopwords):
+                        q = self.index.Q(**{field: word})
+                        if required_filter is None:
+                            required_filter = q
+                        else:
+                            required_filter |= q
+            filters.append(required_filter)
+        if not filters:
+            return []
+        params = {}
+        if book:
+            params['is_book'] = True
+        if picture:
+            params['picture_id__gt'] = 0
+        else:
+            params['book_id__gt'] = 0
+        query = self.index.query(**params)
+        query = self.apply_filters(query, filters).field_limit(score=True, all_fields=True)
+        result_class = PictureResult if picture else SearchResult
+        return [result_class(found, how_found='search_words', query_terms=words) for found in query.execute()]
 
     def get_snippets(self, searchresult, query, field='text', num=1):
         """
@@ -822,120 +968,38 @@ class Search(SolrIndex):
                 text = snippets.get((int(position),
                                      int(length)))
                 snip = self.index.highlight(text=text, field=field, q=query)
-                snips[idx] = snip
-                if snip:
-                    num -= 1
+                if not snip and field == 'text':
+                    snip = self.index.highlight(text=text, field='text_nonstem', q=query)
+                if snip not in snips:
+                    snips[idx] = snip
+                    if snip:
+                        num -= 1
                 idx += 1
 
-        except IOError, e:
-            log.error("Cannot open snippet file for book id = %d [rev=%s], %s" % (book_id, revision, e))
+        except IOError as e:
+            book = catalogue.models.Book.objects.filter(id=book_id)
+            if not book:
+                log.error("Book does not exist for book id = %d" % book_id)
+            elif not book.get().children.exists():
+                log.error("Cannot open snippet file for book id = %d [rev=%s], %s" % (book_id, revision, e))
             return []
         finally:
             snippets.close()
 
-            # remove verse end markers..
-        snips = map(lambda s: s and s.replace("/\n", "\n"), snips)
+        # remove verse end markers..
+        snips = [s.replace("/\n", "\n") if s else s for s in snips]
 
         searchresult.snippets = snips
 
         return snips
 
-    def hint_tags(self, query, pdcounter=True, prefix=True):
-        """
-        Return auto-complete hints for tags
-        using prefix search.
-        """
-        q = self.index.Q()
-        query = query.strip()
-        for field in ['tag_name', 'tag_name_pl']:
-            if prefix:
-                q |= self.index.Q(**{field: query + "*"})
-            else:
-                q |= self.make_term_query(query, field=field)
-        qu = self.index.query(q)
-
-        return self.search_tags(qu, pdcounter=pdcounter)
-
-    def search_tags(self, query, filters=None, pdcounter=False):
-        """
-        Search for Tag objects using query.
-        """
-        if not filters: filters = []
-        if not pdcounter:
-            filters.append(~self.index.Q(is_pdcounter=True))
-        res = self.apply_filters(query, filters).execute()
-
-        tags = []
-        pd_tags = []
-
-        for doc in res:
-            is_pdcounter = doc.get('is_pdcounter', False)
-            category = doc.get('tag_category')
-            try:
-                if is_pdcounter == True:
-                    if category == 'pd_author':
-                        tag = PDCounterAuthor.objects.get(id=doc.get('tag_id'))
-                    elif category == 'pd_book':
-                        tag = PDCounterBook.objects.get(id=doc.get('tag_id'))
-                        tag.category = 'pd_book'  # make it look more lik a tag.
-                    else:
-                        print ("Warning. cannot get pdcounter tag_id=%d from db; cat=%s" % (int(doc.get('tag_id')), category)).encode('utf-8')
-                    pd_tags.append(tag)
-                else:
-                    tag = catalogue.models.Tag.objects.get(id=doc.get("tag_id"))
-                    tags.append(tag)
-
-            except catalogue.models.Tag.DoesNotExist: pass
-            except PDCounterAuthor.DoesNotExist: pass
-            except PDCounterBook.DoesNotExist: pass
-
-        tags_slugs = set(map(lambda t: t.slug, tags))
-        tags = tags + filter(lambda t: not t.slug in tags_slugs, pd_tags)
-
-        log.debug('search_tags: %s' % tags)
-
-        return tags
-
-    def hint_books(self, query, prefix=True):
-        """
-        Returns auto-complete hints for book titles
-        Because we do not index 'pseudo' title-tags.
-        Prefix search.
-        """
-        q = self.index.Q()
-        query = query.strip()
-        if prefix:
-            q |= self.index.Q(title=query + "*")
-        else:
-            q |= self.make_term_query(query, field='title')
-        qu = self.index.query(q)
-        only_books = self.index.Q(is_book=True)
-        return self.search_books(qu, [only_books])
-
-    def search_books(self, query, filters=None, max_results=10):
-        """
-        Searches for Book objects using query
-        """
-        bks = []
-        bks_found = set()
-        query = query.query(is_book=True)
-        res = self.apply_filters(query, filters).field_limit(['book_id'])
-        for r in res:
-            try:
-                bid = r['book_id']
-                if not bid in bks_found:
-                    bks.append(catalogue.models.Book.objects.get(id=bid))
-                    bks_found.add(bid)
-            except catalogue.models.Book.DoesNotExist: pass
-        return bks
-
     @staticmethod
     def apply_filters(query, filters):
         """
         Apply filters to a query
         """
-        if filters is None: filters = []
+        if filters is None:
+            filters = []
         filters = filter(lambda x: x is not None, filters)
         for f in filters:
             query = query.query(f)