Funding: behave nicer with time conflicts.
[wolnelektury.git] / apps / search / index.py
index 050fc5b..85bcb61 100644 (file)
 # -*- coding: utf-8 -*-
+
 from django.conf import settings
-from lucene import SimpleFSDirectory, IndexWriter, File, Field, \
-    NumericField, Version, Document, JavaError, IndexSearcher, \
-    QueryParser, Term, PerFieldAnalyzerWrapper, \
-    SimpleAnalyzer, PolishAnalyzer, ArrayList, \
-    KeywordAnalyzer, NumericRangeQuery, BooleanQuery, \
-    BlockJoinQuery, BlockJoinCollector, TermsFilter, \
-    HashSet, BooleanClause, Term
-    # KeywordAnalyzer
+
 import os
+import re
 import errno
 from librarian import dcparser
 from librarian.parser import WLDocument
+from lxml import etree
 import catalogue.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
+
+log = logging.getLogger('search')
+
+class SolrIndex(object):
+    def __init__(self, mode=None):
+        self.index = custom.CustomSolrInterface(settings.SOLR, mode=mode)
+
+
+class Snippets(object):
+    """
+    This class manages snippet files for indexed object (book)
+    the snippets are concatenated together, and their positions and
+    lengths are kept in lucene index fields.
+    """
+    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
+        self.book_id = book_id
+        self.revision = revision
+        self.file = None
 
+    @property
+    def path(self):
+        if self.revision: fn = "%d.%d" % (self.book_id, self.revision)
+        else: fn = "%d" % self.book_id
 
-class WLAnalyzer(PerFieldAnalyzerWrapper):
-    def __init__(self):
-        polish = PolishAnalyzer(Version.LUCENE_34)
-        simple = SimpleAnalyzer(Version.LUCENE_34)
-        keyword = KeywordAnalyzer(Version.LUCENE_34)
-        # not sure if needed: there's NOT_ANALYZED meaning basically the same
-
-        PerFieldAnalyzerWrapper.__init__(self, polish)
+        return os.path.join(settings.SEARCH_INDEX, self.SNIPPET_DIR, fn)
 
-        self.addAnalyzer("tags", simple)
-        self.addAnalyzer("technical_editors", simple)
-        self.addAnalyzer("editors", simple)
-        self.addAnalyzer("url", keyword)
-        self.addAnalyzer("source_url", keyword)
-        self.addAnalyzer("source_name", simple)
-        self.addAnalyzer("publisher", simple)
-        self.addAnalyzer("author", simple)
-        self.addAnalyzer("is_book", keyword)
+    def open(self, mode='r'):
+        """
+        Open the snippet file. Call .close() afterwards.
+        """
+        if not 'b' in mode:
+            mode += 'b'
+
+        if 'w' in mode:
+            if os.path.exists(self.path):
+                self.revision = 1
+                while True:
+                    if not os.path.exists(self.path):
+                        break
+                    self.revision += 1
+
+        self.file = open(self.path, mode)
+        self.position = 0
+        return self
 
-        #self.addanalyzer("fragment_anchor", keyword)
+    def add(self, snippet):
+        """
+        Append a snippet (unicode) to the snippet file.
+        Return a (position, length) tuple
+        """
+        txt = snippet.encode('utf-8')
+        l = len(txt)
+        self.file.write(txt)
+        pos = (self.position, l)
+        self.position += l
+        return pos
+
+    def get(self, pos):
+        """
+        Given a tuple of (position, length) return an unicode
+        of the snippet stored there.
+        """
+        self.file.seek(pos[0], 0)
+        txt = self.file.read(pos[1]).decode('utf-8')
+        return txt
 
+    def close(self):
+        """Close snippet file"""
+        if self.file:
+            self.file.close()
 
-class IndexStore(object):
+    def remove(self):
+        self.revision = None
+        try:
+            os.unlink(self.path)
+            self.revision = 0
+            while True:
+                self.revision += 1
+                os.unlink(self.path)
+        except OSError:
+            pass
+
+
+class Index(SolrIndex):
+    """
+    Class indexing books.
+    """
     def __init__(self):
-        self.make_index_dir()
-        self.store = SimpleFSDirectory(File(settings.SEARCH_INDEX))
+        super(Index, self).__init__(mode='rw')
 
-    def make_index_dir(self):
-        try:
-            os.makedirs(settings.SEARCH_INDEX)
-        except OSError as exc:
-            if exc.errno == errno.EEXIST:
-                pass
-            else: raise
+    def delete_query(self, *queries):
+        """
+        index.delete(queries=...) doesn't work, so let's reimplement it
+        using deletion of list of uids.
+        """
+        uids = set()
+        for q in queries:
+            if isinstance(q, sunburnt.search.LuceneQuery):
+                q = self.index.query(q)
+            q.field_limiter.update(['uid'])
+            st = 0
+            rows = 100
+            while True:
+                ids = q.paginate(start=st, rows=rows).execute()
+                if not len(ids):
+                    break
+                for res in ids:
+                    uids.add(res['uid'])
+                st += rows
+        if uids:
+            self.index.delete(uids)
+            return True
+        else:
+            return False
 
+    def index_tags(self, *tags, **kw):
+        """
+        Re-index global tag list.
+        Removes all tags from index, then index them again.
+        Indexed fields include: id, name (with and without polish stems), category
+        """
+        log.debug("Indexing tags")
+        remove_only = kw.get('remove_only', False)
+        # first, remove tags from index.
+        if tags:
+            tag_qs = []
+            for tag in tags:
+                q_id = self.index.Q(tag_id=tag.id)
+
+                if isinstance(tag, PDCounterAuthor):
+                    q_cat = self.index.Q(tag_category='pd_author')
+                elif isinstance(tag, PDCounterBook):
+                    q_cat = self.index.Q(tag_category='pd_book')
+                else:
+                    q_cat = self.index.Q(tag_category=tag.category)
+
+                q_id_cat = self.index.Q(q_id & q_cat)
+                tag_qs.append(q_id_cat)
+            self.delete_query(tag_qs)
+        else:  # all
+            q = self.index.Q(tag_id__any=True)
+            self.delete_query(q)
+
+        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(), \
+                    PDCounterBook.objects.all())
+
+            for tag in tags:
+                if isinstance(tag, PDCounterAuthor):
+                    doc = {
+                        "tag_id": int(tag.id),
+                        "tag_name": tag.name,
+                        "tag_name_pl": tag.name,
+                        "tag_category": 'pd_author',
+                        "is_pdcounter": True,
+                        "uid": "tag%d_pd_a" % tag.id
+                        }
+                elif isinstance(tag, PDCounterBook):
+                    doc = {
+                        "tag_id": int(tag.id),
+                        "tag_name": tag.title,
+                        "tag_name_pl": tag.title,
+                        "tag_category": 'pd_book',
+                        "is_pdcounter": True,
+                        "uid": "tag%d_pd_b" % tag.id
+                        }
+                else:
+                    doc = {
+                        "tag_id": int(tag.id),
+                        "tag_name": tag.name,
+                        "tag_name_pl": tag.name,
+                        "tag_category": tag.category,
+                        "is_pdcounter": False,
+                        "uid": "tag%d" % tag.id
+                        }
+                self.index.add(doc)
 
-class Index(IndexStore):
-    def __init__(self, analyzer=None):
-        IndexStore.__init__(self)
-        self.index = None
-        if not analyzer:
-            analyzer = WLAnalyzer()
-        self.analyzer = analyzer
+    def create_book_doc(self, book):
+        """
+        Create a lucene document referring book id.
+        """
+        doc = {
+            'book_id': int(book.id),
+            }
+        if book.parent is not None:
+            doc["parent_id"] = int(book.parent.id)
+        return doc
 
-    def open(self, analyzer=None):
-        if self.index:
-            raise Exception("Index is already opened")
-        self.index = IndexWriter(self.store, self.analyzer,\
-                                 IndexWriter.MaxFieldLength.LIMITED)
-        return self.index
+    def remove_book(self, book_or_id, remove_snippets=True):
+        """Removes a book from search index.
+        book - Book instance."""
+        if isinstance(book_or_id, catalogue.models.Book):
+            book_id = book_or_id.id
+        else:
+            book_id = book_or_id
 
-    def close(self):
-        self.index.optimize()
-        self.index.close()
-        self.index = None
+        self.delete_query(self.index.Q(book_id=book_id))
 
-    def remove_book(self, book):
-        q = NumericRangeQuery.newIntRange("book_id", book.id, book.id, True,True)
-        self.index.deleteDocuments(q)
+        if remove_snippets:
+            snippets = Snippets(book_id)
+            snippets.remove()
 
-    def index_book(self, book, overwrite=True):
+    def index_book(self, book, book_info=None, overwrite=True):
+        """
+        Indexes the book.
+        Creates a lucene document for extracted metadata
+        and calls self.index_content() to index the contents of the book.
+        """
         if overwrite:
-            self.remove_book(book)
+            # we don't remove snippets, since they might be still needed by
+            # threads using not reopened index
+            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'])
+        # let's not index it - it's only used for extracting publish date
+        if 'source_name' in meta_fields:
+            del meta_fields['source_name']
+
+        for n, f in meta_fields.items():
+            book_doc[n] = f
+
+        book_doc['uid'] = "book%s" % book_doc['book_id']
+        self.index.add(book_doc)
+        del book_doc
+        book_fields = {
+            'title': meta_fields['title'],
+            'authors': meta_fields['authors'],
+            'published_date': meta_fields['published_date']
+            }
 
-        doc = self.extract_metadata(book)
-        parts = self.extract_content(book)
-        block = ArrayList().of_(Document)
+        if 'translators' in meta_fields:
+            book_fields['translators'] = meta_fields['translators']
 
-        for p in parts:
-            block.add(p)
-        block.add(doc)
-        self.index.addDocuments(block)
+        self.index_content(book, book_fields=book_fields)
 
     master_tags = [
         'opowiadanie',
@@ -94,29 +270,39 @@ class Index(IndexStore):
         'dramat_wierszowany_l',
         'dramat_wierszowany_lp',
         'dramat_wspolczesny', 'liryka_l', 'liryka_lp',
-        'wywiad'
+        'wywiad',
         ]
 
-    def create_book_doc(self, book):
+    ignore_content_tags = [
+        'uwaga', 'extra',
+        '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']
+
+    published_date_re = re.compile("([0-9]+)[\]. ]*$")
+
+    def extract_metadata(self, book, book_info=None, dc_only=None):
         """
-        Create a lucene document connected to the book
+        Extract metadata from book and returns a map of fields keyed by fieldname
         """
-        doc = Document()
-        doc.add(NumericField("book_id", Field.Store.YES, True).setIntValue(book.id))
-        if book.parent is not None:
-            doc.add(NumericField("parent_id", Field.Store.YES, True).setIntValue(book.parent.id))
-        return doc
+        fields = {}
 
-    def extract_metadata(self, book):
-        book_info = dcparser.parse(book.xml_file)
+        if book_info is None:
+            book_info = dcparser.parse(open(book.xml_file.path))
 
-        doc = self.create_book_doc(book)
-        doc.add(Field("slug", book.slug, Field.Store.NO, Field.Index.ANALYZED_NO_NORMS))
-        doc.add(Field("tags", ','.join([t.name for t in book.tags]), Field.Store.NO, Field.Index.ANALYZED))
-        doc.add(Field("is_book", 'true', Field.Store.NO, Field.Index.NOT_ANALYZED))
+        fields['slug'] = book.slug
+        fields['tags'] = [t.name  for t in book.tags]
+        fields['is_book'] = True
 
         # validator, name
         for field in dcparser.BookInfo.FIELDS:
+            if dc_only and field.name not in dc_only:
+                continue
             if hasattr(book_info, field.name):
                 if not getattr(book_info, field.name):
                     continue
@@ -126,183 +312,629 @@ class Index(IndexStore):
                     s = getattr(book_info, field.name)
                     if field.multiple:
                         s = ', '.join(s)
-                    try:
-                        doc.add(Field(field.name, s, Field.Store.NO, Field.Index.ANALYZED))
-                    except JavaError as je:
-                        raise Exception("failed to add field: %s = '%s', %s(%s)" % (field.name, s, je.message, je.args))
+                    fields[field.name] = s
                 elif type_indicator == dcparser.as_person:
                     p = getattr(book_info, field.name)
                     if isinstance(p, dcparser.Person):
                         persons = unicode(p)
                     else:
                         persons = ', '.join(map(unicode, p))
-                    doc.add(Field(field.name, persons, Field.Store.NO, Field.Index.ANALYZED))
+                    fields[field.name] = persons
                 elif type_indicator == dcparser.as_date:
                     dt = getattr(book_info, field.name)
-                    doc.add(Field(field.name, "%04d%02d%02d" % (dt.year, dt.month, dt.day), Field.Store.NO, Field.Index.NOT_ANALYZED))
-        return doc
+                    fields[field.name] = dt
+
+        # get published date
+        pd = None
+        if hasattr(book_info, 'source_name') and book_info.source_name:
+            match = self.published_date_re.search(book_info.source_name)
+            if match is not None:
+                pd = str(match.groups()[0])
+        if not pd: pd = ""
+        fields["published_date"] = pd
+
+        return fields
+
+    # def add_gaps(self, fields, fieldname):
+    #     """
+    #     Interposes a list of fields with gap-fields, which are indexed spaces and returns it.
+    #     This allows for doing phrase queries which do not overlap the gaps (when slop is 0).
+    #     """
+    #     def gap():
+    #         while True:
+    #             yield Field(fieldname, ' ', Field.Store.NO, Field.Index.NOT_ANALYZED)
+    #     return reduce(lambda a, b: a + b, zip(fields, gap()))[0:-1]
 
     def get_master(self, root):
+        """
+        Returns the first master tag from an etree.
+        """
         for master in root.iter():
             if master.tag in self.master_tags:
                 return master
 
-    def extract_content(self, book):
-        wld = WLDocument.from_file(book.xml_file.path)
+    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.
+        """
+        wld = WLDocument.from_file(book.xml_file.path, parse_dublincore=False)
         root = wld.edoc.getroot()
 
-        # first we build a sequence of top-level items.
-        # book_id
-        # header_index - the 0-indexed position of header element.
-        # content
         master = self.get_master(root)
         if master is None:
             return []
-        
-        header_docs = []
-        for header, position in zip(list(master), range(len(master))):
-            doc = self.create_book_doc(book)
-            doc.add(NumericField("header_index", Field.Store.YES, True).setIntValue(position))
-            doc.add(Field("header_type", header.tag, Field.Store.YES, Field.Index.NOT_ANALYZED))
-            content = u' '.join([t for t in header.itertext()])
-            doc.add(Field("content", content, Field.Store.NO, Field.Index.ANALYZED))
-            header_docs.append(doc)
-
-        def walker(node):
-            yield node, None
-            for child in list(node):
-                for b, e in walker(child):
-                    yield b, e
-            yield None, node
+
+        def walker(node, ignore_tags=[]):
+
+            if node.tag not in ignore_tags:
+                yield node, None, None
+                if node.text is not None:
+                    yield None, node.text, None
+                for child in list(node):
+                    for b, t, e in walker(child):
+                        yield b, t, e
+                yield None, None, node
+
+            if node.tail is not None:
+                yield None, node.tail, None
             return
 
-        # Then we create a document for each fragments
-        # fragment_anchor - the anchor
-        # themes - list of themes [not indexed]
-        fragment_docs = []
-        # will contain (framgent id -> { content: [], themes: [] }
+        def fix_format(text):
+            #            separator = [u" ", u"\t", u".", u";", u","]
+            if isinstance(text, list):
+                # need to join it first
+                text = filter(lambda s: s is not None, content)
+                text = u' '.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" ")
+
+            return re.sub("(?m)/$", "", text)
+
+        def add_part(snippets, **fields):
+            doc = self.create_book_doc(book)
+            for n, v in book_fields.items():
+                doc[n] = v
+
+            doc['header_index'] = fields["header_index"]
+            doc['header_span'] = 'header_span' in fields and fields['header_span'] or 1
+            doc['header_type'] = fields['header_type']
+
+            doc['text'] = fields['text']
+
+            # snippets
+            snip_pos = snippets.add(fields["text"])
+
+            doc['snippets_position'] = snip_pos[0]
+            doc['snippets_length'] = snip_pos[1]
+            if snippets.revision:
+                doc["snippets_revision"] = snippets.revision
+
+            if 'fragment_anchor' in fields:
+                doc["fragment_anchor"] = fields['fragment_anchor']
+
+            if 'themes' in fields:
+                doc['themes'] = fields['themes']
+            doc['uid'] = "part%s%s%s" % (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 = {}
-        for start, end in walker(master):
-            if start is not None and start.tag == 'begin':
-                fid = start.attrib['id'][1:]
-                fragments[fid] = {'content': [], 'themes': []}
-                fragments[fid]['content'].append(start.tail)
-            elif start is not None and start.tag == 'motyw':
-                fid = start.attrib['id'][1:]
-                fragments[fid]['themes'].append(start.text)
-                fragments[fid]['content'].append(start.tail)
-            elif start is not None and start.tag == 'end':
-                fid = start.attrib['id'][1:]
-                if fid not in fragments:
-                    continue  # a broken <end> node, skip it
-                frag = fragments[fid]
-                del fragments[fid]
-
-                def jstr(l):
-                    return u' '.join(map(
-                        lambda x: x == None and u'(none)' or unicode(x),
-                        l))
-                s = u"Fragment %s complete, themes: %s contents: %s" % \
-                      (fid, jstr(frag['themes']), jstr(frag['content']))
-                print(s.encode('utf-8'))
-
-                doc = self.create_book_doc(book)
-                doc.add(Field("fragment_anchor", fid,
-                              Field.Store.YES, Field.Index.NOT_ANALYZED))
-                doc.add(Field("content",
-                              u' '.join(filter(lambda s: s is not None, frag['content'])),
-                              Field.Store.NO, Field.Index.ANALYZED))
-                doc.add(Field("themes",
-                              u' '.join(filter(lambda s: s is not None, frag['themes'])),
-                              Field.Store.NO, Field.Index.ANALYZED))
-
-                fragment_docs.append(doc)
-            elif start is not None:
-                for frag in fragments.values():
-                    frag['content'].append(start.text)
-            elif end is not None:
-                for frag in fragments.values():
-                    frag['content'].append(end.tail)
-
-        return header_docs + fragment_docs
-
-    def __enter__(self):
-        self.open()
+        snippets = Snippets(book.id).open('w')
+        try:
+            for header, position in zip(list(master), range(len(master))):
+
+                if header.tag in self.skip_header_tags:
+                    continue
+                if header.tag is etree.Comment:
+                    continue
+
+                # section content
+                content = []
+                footnote = []
+
+                def all_content(text):
+                    for frag in fragments.values():
+                        frag['text'].append(text)
+                    content.append(text)
+                handle_text = [all_content]
+
+                for start, text, end in walker(header, ignore_tags=self.ignore_content_tags):
+                    # handle footnotes
+                    if start is not None and start.tag in self.footnote_tags:
+                        footnote = []
+
+                        def collect_footnote(t):
+                            footnote.append(t)
+
+                        handle_text.append(collect_footnote)
+                    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),
+                                       is_footnote=True)
+                        self.index.add(doc)
+                        footnote = []
+
+                    # 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}
+
+                    # themes for this fragment
+                    elif start is not None and start.tag == 'motyw':
+                        fid = start.attrib['id'][1:]
+                        handle_text.append(None)
+                        if start.text is not None:
+                            fragments[fid]['themes'] += map(unicode.strip, map(unicode, (start.text.split(','))))
+                    elif end is not None and end.tag == 'motyw':
+                        handle_text.pop()
+
+                    elif start is not None and start.tag == 'end':
+                        fid = start.attrib['id'][1:]
+                        if fid not in fragments:
+                            continue  # a broken <end> node, skip it
+                        frag = fragments[fid]
+                        if frag['themes'] == []:
+                            continue  # empty themes list.
+                        del fragments[fid]
+
+                        doc = add_part(snippets,
+                                       header_type=frag['start_header'],
+                                       header_index=frag['start_section'],
+                                       header_span=position - frag['start_section'] + 1,
+                                       fragment_anchor=fid,
+                                       text=fix_format(frag['text']),
+                                       themes=frag['themes'])
+                        self.index.add(doc)
+
+                        # Collect content.
+
+                    if text is not None and handle_text is not []:
+                        hdl = handle_text[-1]
+                        if hdl is not None:
+                            hdl(text)
+
+                        # in the end, add a section text.
+                doc = add_part(snippets, header_index=position,
+                               header_type=header.tag, text=fix_format(content))
+
+                self.index.add(doc)
+
+        finally:
+            snippets.close()
+
+
+class SearchResult(object):
+    def __init__(self, doc, how_found=None, query=None, query_terms=None):
+        #        self.search = search
+        self.boost = 1.0
+        self._hits = []
+        self._processed_hits = None  # processed hits
+        self.snippets = []
+        self.query_terms = query_terms
+
+        if 'score' in doc:
+            self._score = doc['score']
+        else:
+            self._score = 0
+
+        self.book_id = int(doc["book_id"])
+
+        try:
+            self.published_date = int(doc.get("published_date"))
+        except ValueError:
+            self.published_date = 0
+
+        # content hits
+        header_type = doc.get("header_type", None)
+        # we have a content hit in some header of fragment
+        if header_type is not None:
+            sec = (header_type, int(doc["header_index"]))
+            header_span = doc['header_span']
+            header_span = header_span is not None and int(header_span) or 1
+            fragment = doc.get("fragment_anchor", None)
+            snippets_pos = (doc['snippets_position'], doc['snippets_length'])
+            snippets_rev = doc.get('snippets_revision', None)
+
+            hit = (sec + (header_span,), fragment, self._score, {
+                'how_found': how_found,
+                'snippets_pos': snippets_pos,
+                'snippets_revision': snippets_rev,
+                'themes': doc.get('themes', []),
+                'themes_pl': doc.get('themes_pl', [])
+                })
+
+            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))
+
+    def __str__(self):
+        return unicode(self).encode('utf-8')
+
+    @property
+    def score(self):
+        return self._score * self.boost
+
+    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))
+        self._hits += other._hits
+        if other.score > self.score:
+            self._score = other._score
         return self
 
-    def __exit__(self, type, value, tb):
-        self.close()
+    def get_book(self):
+        if hasattr(self, '_book'):
+            return self._book
+        self._book = catalogue.models.Book.objects.get(id=self.book_id)
+        return self._book
+
+    book = property(get_book)
+
+    POSITION = 0
+    FRAGMENT = 1
+    POSITION_INDEX = 1
+    POSITION_SPAN = 2
+    SCORE = 2
+    OTHER = 3
+
+    @property
+    def hits(self):
+        if self._processed_hits is not None:
+            return self._processed_hits
+
+        # 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)
+
+        # 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)
+
+        hits = []
+
+        def remove_duplicates(lst, keyfn, compare):
+            els = {}
+            for e in lst:
+                eif = keyfn(e)
+                if eif in els:
+                    if compare(els[eif], e) >= 1:
+                        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]))
+
+        # remove duplicate sections
+        sections = {}
+
+        for s in sect:
+            si = s[self.POSITION][self.POSITION_INDEX]
+            # skip existing
+            if si in sections:
+                if sections[si]['score'] >= s[self.SCORE]:
+                    continue
+
+            m = {'score': s[self.SCORE],
+                 'section_number': s[self.POSITION][self.POSITION_INDEX] + 1,
+                 }
+            m.update(s[self.OTHER])
+            sections[si] = m
+
+        hits = sections.values()
+
+        for f in frags:
+            try:
+                frag = catalogue.models.Fragment.objects.get(anchor=f[self.FRAGMENT], book__id=self.book_id)
+            except catalogue.models.Fragment.DoesNotExist:
+                # stale index
+                continue
+            # Figure out if we were searching for a token matching some word in theme name.
+            themes = frag.tags.filter(category='theme')
+            themes_hit = set()
+            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)
+                    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)
+                if th:
+                    return th[0]
+                else:
+                    return None
+            themes_hit = filter(lambda a: a is not None, map(theme_by_name, themes_hit))
+
+            m = {'score': f[self.SCORE],
+                 'fragment': frag,
+                 'section_number': f[self.POSITION][self.POSITION_INDEX] + 1,
+                 'themes': themes,
+                 'themes_hit': themes_hit
+                 }
+            m.update(f[self.OTHER])
+            hits.append(m)
+
+        hits.sort(lambda a, b: cmp(a['score'], b['score']), reverse=True)
+
+        self._processed_hits = hits
+
+        return hits
+
+    @staticmethod
+    def aggregate(*result_lists):
+        books = {}
+        for rl in result_lists:
+            for r in rl:
+                if r.book_id in books:
+                    books[r.book_id].merge(r)
+                else:
+                    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 __len__(self):
+        return len(self.hits)
 
+    def snippet_pos(self, idx=0):
+        return self.hits[idx]['snippets_pos']
+
+    def snippet_revision(self, idx=0):
+        try:
+            return self.hits[idx]['snippets_revision']
+        except:
+            return None
 
-class Search(IndexStore):
-    def __init__(self, default_field="content"):
-        IndexStore.__init__(self)
-        self.analyzer = PolishAnalyzer(Version.LUCENE_34)
-        ## self.analyzer = WLAnalyzer()
-        self.searcher = IndexSearcher(self.store, True)
-        self.parser = QueryParser(Version.LUCENE_34, default_field,
-                                  self.analyzer)
 
-        self.parent_filter = TermsFilter()
-        self.parent_filter.addTerm(Term("is_book", "true"))
+class Search(SolrIndex):
+    """
+    Search facilities.
+    """
+    def __init__(self, default_field="text"):
+        super(Search, self).__init__(mode='r')
 
-    def query(self, query):
-        return self.parser.parse(query)
 
-    def wrapjoins(self, query, fields=[]):
+    def make_term_query(self, query, field='text', modal=operator.or_):
         """
-        This functions modifies the query in a recursive way,
-        so Term and Phrase Queries contained, which match
-        provided fields are wrapped in a BlockJoinQuery,
-        and so delegated to children documents.
+        Returns term queries joined by boolean query.
+        modal - applies to boolean query
+        fuzzy - should the query by fuzzy.
         """
-        if BooleanQuery.instance_(query):
-            qs = BooleanQuery.cast_(query)
-            for clause in qs:
-                clause = BooleanClause.cast_(clause)
-                clause.setQuery(self.wrapjoins(clause.getQuery(), fields))
-            return qs
-        else:
-            termset = HashSet()
-            query.extractTerms(termset)
-            for t in termset:
-                t = Term.cast_(t)
-                if t.field() not in fields:
-                    return query
-            return BlockJoinQuery(query, self.parent_filter,
-                                  BlockJoinQuery.ScoreMode.Total)
+        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
+
+    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))
+
+        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 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))
+
+        query = self.index.Q()
 
-    def simple_search(self, query, max_results=50):
-        """Returns (books, total_hits)
+        for fld in fields:
+            query = self.index.Q(query | self.make_term_query(searched, fld))
+
+        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]
+
+
+    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')
 
-        tops = self.searcher.search(self.query(query), max_results)
-        bks = []
-        for found in tops.scoreDocs:
-            doc = self.searcher.doc(found.doc)
-            bks.append(catalogue.models.Book.objects.get(id=doc.get("book_id")))
-        return (bks, tops.totalHits)
+        query = self.index.query(q).query(q_themes).field_limit(score=True, all_fields=True)
+        res = query.execute()
 
-    def search(self, query, max_results=50):
-        query = self.query(query)
-        query = self.wrapjoins(query, ["content", "themes"])
+        for found in res:
+            books.append(SearchResult(found, how_found='search_everywhere_themesXcontent', query_terms=query_terms))
 
-        tops = self.searcher.search(query, max_results)
-        bks = []
-        for found in tops.scoreDocs:
-            doc = self.searcher.doc(found.doc)
-            bks.append(catalogue.models.Book.objects.get(id=doc.get("book_id")))
-        return (bks, tops.totalHits)
-
-    def bsearch(self, query, max_results=50):
-        q = self.query(query)
-        f = TermsFilter()
-        f.addTerm(Term("is_book", "true"))
-        bjq = BlockJoinQuery(q, f, BlockJoinQuery.ScoreMode.Avg)
-
-        tops = self.searcher.search(bjq, max_results)
+        # query themes/content x author/title/tags
+        in_content = self.index.Q()
+        in_meta = self.index.Q()
+
+        for fld in ['themes_pl', 'text']:
+            in_content |= self.make_term_query(searched, field=fld)
+
+        for fld in ['tags', 'authors', 'title']:
+            in_meta |= self.make_term_query(searched, field=fld)
+
+        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))
+
+        return books
+
+    def get_snippets(self, searchresult, query, field='text', num=1):
+        """
+        Returns a snippet for found scoreDoc.
+        """
+        maxnum = len(searchresult)
+        if num is None or num < 0 or num > maxnum:
+            num = maxnum
+        book_id = searchresult.book_id
+        revision = searchresult.snippet_revision()
+        snippets = Snippets(book_id, revision=revision)
+        snips = [None] * maxnum
+        try:
+            snippets.open()
+            idx = 0
+            while idx < maxnum and num > 0:
+                position, length = searchresult.snippet_pos(idx)
+                if position is None or length is None:
+                    continue
+                text = snippets.get((int(position),
+                                     int(length)))
+                snip = self.index.highlight(text=text, field=field, q=query)
+                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))
+            return []
+        finally:
+            snippets.close()
+
+            # remove verse end markers..
+        snips = map(lambda s: s and s.replace("/\n", "\n"), 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).exclude(tag_category="book")
+
+        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 = []
-        for found in tops.scoreDocs:
-            doc = self.searcher.doc(found.doc)
-            bks.append(catalogue.models.Book.objects.get(id=doc.get("book_id")))
-        return (bks, tops.totalHits)
+        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 = []
+        filters = filter(lambda x: x is not None, filters)
+        for f in filters:
+            query = query.query(f)
+        return query