search input field,
[wolnelektury.git] / apps / search / index.py
index a6d5cf6..cc478ee 100644 (file)
@@ -1,29 +1,47 @@
 # -*- coding: utf-8 -*-
 # -*- coding: utf-8 -*-
+
 from django.conf import settings
 from django.conf import settings
-from lucene import SimpleFSDirectory, IndexWriter, File, Field, \
+from lucene import SimpleFSDirectory, IndexWriter, CheckIndex, \
+    File, Field, Integer, \
     NumericField, Version, Document, JavaError, IndexSearcher, \
     NumericField, Version, Document, JavaError, IndexSearcher, \
-    QueryParser, Term, PerFieldAnalyzerWrapper, \
+    QueryParser, PerFieldAnalyzerWrapper, \
     SimpleAnalyzer, PolishAnalyzer, ArrayList, \
     SimpleAnalyzer, PolishAnalyzer, ArrayList, \
-    KeywordAnalyzer, NumericRangeQuery, BooleanQuery, \
-    BlockJoinQuery, BlockJoinCollector, TermsFilter, \
+    KeywordAnalyzer, NumericRangeQuery, NumericRangeFilter, BooleanQuery, \
+    BlockJoinQuery, BlockJoinCollector, Filter, TermsFilter, ChainedFilter, \
     HashSet, BooleanClause, Term, CharTermAttribute, \
     HashSet, BooleanClause, Term, CharTermAttribute, \
-    PhraseQuery, StringReader
+    PhraseQuery, MultiPhraseQuery, StringReader, TermQuery, \
+    FuzzyQuery, FuzzyTermEnum, PrefixTermEnum, Sort, Integer, \
+    SimpleHTMLFormatter, Highlighter, QueryScorer, TokenSources, TextFragment, \
+    BooleanFilter, TermsFilter, FilterClause, QueryWrapperFilter, \
+    initVM, CLASSPATH, JArray, JavaError
     # KeywordAnalyzer
     # KeywordAnalyzer
+
+# Initialize jvm
+JVM = initVM(CLASSPATH)
+
 import sys
 import os
 import sys
 import os
+import re
 import errno
 from librarian import dcparser
 from librarian.parser import WLDocument
 import catalogue.models
 from multiprocessing.pool import ThreadPool
 import errno
 from librarian import dcparser
 from librarian.parser import WLDocument
 import catalogue.models
 from multiprocessing.pool import ThreadPool
+from threading import current_thread
 import atexit
 import atexit
+import traceback
 
 
 class WLAnalyzer(PerFieldAnalyzerWrapper):
     def __init__(self):
         polish = PolishAnalyzer(Version.LUCENE_34)
 
 
 class WLAnalyzer(PerFieldAnalyzerWrapper):
     def __init__(self):
         polish = PolishAnalyzer(Version.LUCENE_34)
+        #        polish_gap.setPositionIncrementGap(999)
+
         simple = SimpleAnalyzer(Version.LUCENE_34)
         simple = SimpleAnalyzer(Version.LUCENE_34)
+        #        simple_gap.setPositionIncrementGap(999)
+
         keyword = KeywordAnalyzer(Version.LUCENE_34)
         keyword = KeywordAnalyzer(Version.LUCENE_34)
+
         # not sure if needed: there's NOT_ANALYZED meaning basically the same
 
         PerFieldAnalyzerWrapper.__init__(self, polish)
         # not sure if needed: there's NOT_ANALYZED meaning basically the same
 
         PerFieldAnalyzerWrapper.__init__(self, polish)
@@ -35,13 +53,31 @@ class WLAnalyzer(PerFieldAnalyzerWrapper):
         self.addAnalyzer("source_url", keyword)
         self.addAnalyzer("source_name", simple)
         self.addAnalyzer("publisher", simple)
         self.addAnalyzer("source_url", keyword)
         self.addAnalyzer("source_name", simple)
         self.addAnalyzer("publisher", simple)
-        self.addAnalyzer("author", simple)
+        self.addAnalyzer("authors", simple)
+        self.addAnalyzer("title", simple)
+
         self.addAnalyzer("is_book", keyword)
         self.addAnalyzer("is_book", keyword)
+        # shouldn't the title have two forms? _pl and simple?
+
+        self.addAnalyzer("themes", simple)
+        self.addAnalyzer("themes_pl", polish)
+
+        self.addAnalyzer("tag_name", simple)
+        self.addAnalyzer("tag_name_pl", polish)
+
+        self.addAnalyzer("translators", simple)
 
 
-        #self.addanalyzer("fragment_anchor", keyword)
+        self.addAnalyzer("KEYWORD", keyword)
+        self.addAnalyzer("SIMPLE", simple)
+        self.addAnalyzer("POLISH", polish)
 
 
 class IndexStore(object):
 
 
 class IndexStore(object):
+    """
+    Provides access to search index.
+
+    self.store - lucene index directory
+    """
     def __init__(self):
         self.make_index_dir()
         self.store = SimpleFSDirectory(File(settings.SEARCH_INDEX))
     def __init__(self):
         self.make_index_dir()
         self.store = SimpleFSDirectory(File(settings.SEARCH_INDEX))
@@ -55,9 +91,77 @@ class IndexStore(object):
             else: raise
 
 
             else: raise
 
 
-class Index(IndexStore):
-    def __init__(self, analyzer=None):
+class IndexChecker(IndexStore):
+    def __init__(self):
         IndexStore.__init__(self)
         IndexStore.__init__(self)
+
+    def check(self):
+        checker = CheckIndex(self.store)
+        status = checker.checkIndex()
+        return status
+
+
+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):
+        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.file = None
+
+    def open(self, mode='r'):
+        """
+        Open the snippet file. Call .close() afterwards.
+        """
+        if not 'b' in mode:
+            mode += 'b'
+        self.file = open(os.path.join(settings.SEARCH_INDEX, self.SNIPPET_DIR, str(self.book_id)), mode)
+        self.position = 0
+        return self
+
+    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"""
+        self.file.close()
+
+
+class BaseIndex(IndexStore):
+    """
+    Base index class.
+    Provides basic operations on index: opening, closing, optimizing.
+    """
+    def __init__(self, analyzer=None):
+        super(BaseIndex, self).__init__()
         self.index = None
         if not analyzer:
             analyzer = WLAnalyzer()
         self.index = None
         if not analyzer:
             analyzer = WLAnalyzer()
@@ -70,28 +174,88 @@ class Index(IndexStore):
                                  IndexWriter.MaxFieldLength.LIMITED)
         return self.index
 
                                  IndexWriter.MaxFieldLength.LIMITED)
         return self.index
 
-    def close(self):
+    def optimize(self):
         self.index.optimize()
         self.index.optimize()
+
+    def close(self):
+        try:
+            self.index.optimize()
+        except JavaError, je:
+            print "Error during optimize phase, check index: %s" % je
+
         self.index.close()
         self.index = None
 
         self.index.close()
         self.index = None
 
+    def __enter__(self):
+        self.open()
+        return self
+
+    def __exit__(self, type, value, tb):
+        self.close()
+
+
+class Index(BaseIndex):
+    """
+    Class indexing books.
+    """
+    def __init__(self, analyzer=None):
+        super(Index, self).__init__(analyzer)
+
+    def index_tags(self):
+        """
+        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
+        """
+        q = NumericRangeQuery.newIntRange("tag_id", 0, Integer.MAX_VALUE, True, True)
+        self.index.deleteDocuments(q)
+
+        for tag in catalogue.models.Tag.objects.all():
+            doc = Document()
+            doc.add(NumericField("tag_id", Field.Store.YES, True).setIntValue(tag.id))
+            doc.add(Field("tag_name", tag.name, Field.Store.NO, Field.Index.ANALYZED))
+            doc.add(Field("tag_name_pl", tag.name, Field.Store.NO, Field.Index.ANALYZED))
+            doc.add(Field("tag_category", tag.category, Field.Store.NO, Field.Index.NOT_ANALYZED))
+            self.index.addDocument(doc)
+
+    def create_book_doc(self, book):
+        """
+        Create a lucene document referring book id.
+        """
+        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
+
     def remove_book(self, book):
     def remove_book(self, book):
-        q = NumericRangeQuery.newIntRange("book_id", book.id, book.id, True,True)
+        """Removes a book from search index.
+        book - Book instance."""
+        q = NumericRangeQuery.newIntRange("book_id", book.id, book.id, True, True)
         self.index.deleteDocuments(q)
 
         self.index.deleteDocuments(q)
 
-    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)
         if overwrite:
             self.remove_book(book)
-            
 
 
-        doc = self.extract_metadata(book)
-        parts = self.extract_content(book)
-        block = ArrayList().of_(Document)
+        book_doc = self.create_book_doc(book)
+        meta_fields = self.extract_metadata(book, book_info)
+        for f in meta_fields.values():
+            if isinstance(f, list) or isinstance(f, tuple):
+                for elem in f:
+                    book_doc.add(elem)
+            else:
+                book_doc.add(f)
 
 
-        for p in parts:
-            block.add(p)
-        block.add(doc)
-        self.index.addDocuments(block)
+        self.index.addDocument(book_doc)
+        del book_doc
+
+        self.index_content(book, book_fields=[meta_fields['title'], meta_fields['authors']])
 
     master_tags = [
         'opowiadanie',
 
     master_tags = [
         'opowiadanie',
@@ -102,25 +266,20 @@ class Index(IndexStore):
         'wywiad'
         ]
 
         'wywiad'
         ]
 
-    skip_header_tags = ['autor_utworu', 'nazwa_utworu']
+    skip_header_tags = ['autor_utworu', 'nazwa_utworu', 'dzielo_nadrzedne']
 
 
-    def create_book_doc(self, book):
+    def extract_metadata(self, book, book_info=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'] = Field("slug", book.slug, Field.Store.NO, Field.Index.ANALYZED_NO_NORMS)
+        fields['tags'] = self.add_gaps([Field("tags", t.name, Field.Store.NO, Field.Index.ANALYZED) for t in book.tags], 'tags')
+        fields['is_book'] = Field("is_book", 'true', Field.Store.NO, Field.Index.NOT_ANALYZED)
 
         # validator, name
         for field in dcparser.BookInfo.FIELDS:
 
         # validator, name
         for field in dcparser.BookInfo.FIELDS:
@@ -134,7 +293,7 @@ class Index(IndexStore):
                     if field.multiple:
                         s = ', '.join(s)
                     try:
                     if field.multiple:
                         s = ', '.join(s)
                     try:
-                        doc.add(Field(field.name, s, Field.Store.NO, Field.Index.ANALYZED))
+                        fields[field.name] = 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))
                 elif type_indicator == dcparser.as_person:
                     except JavaError as je:
                         raise Exception("failed to add field: %s = '%s', %s(%s)" % (field.name, s, je.message, je.args))
                 elif type_indicator == dcparser.as_person:
@@ -143,40 +302,43 @@ class Index(IndexStore):
                         persons = unicode(p)
                     else:
                         persons = ', '.join(map(unicode, p))
                         persons = unicode(p)
                     else:
                         persons = ', '.join(map(unicode, p))
-                    doc.add(Field(field.name, persons, Field.Store.NO, Field.Index.ANALYZED))
+                    fields[field.name] = Field(field.name, persons, Field.Store.NO, Field.Index.ANALYZED)
                 elif type_indicator == dcparser.as_date:
                     dt = getattr(book_info, field.name)
                 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] = Field(field.name, "%04d%02d%02d" %\
+                                               (dt.year, dt.month, dt.day), Field.Store.NO, Field.Index.NOT_ANALYZED)
+
+        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):
 
     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
 
         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()
 
         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 []
         master = self.get_master(root)
         if master is None:
             return []
-        
-        header_docs = []
-        for header, position in zip(list(master), range(len(master))):
-            if header.tag in self.skip_header_tags:
-                continue
-            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
 
         def walker(node):
             yield node, None
@@ -186,59 +348,119 @@ class Index(IndexStore):
             yield None, node
             return
 
             yield None, node
             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: [] }
-        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))
-
-                doc = self.create_book_doc(book)
-                doc.add(Field("fragment_anchor", fid,
+        def fix_format(text):
+            return re.sub("(?m)/$", "", text)
+
+        def add_part(snippets, **fields):
+            doc = self.create_book_doc(book)
+            for f in book_fields:
+                doc.add(f)
+
+            doc.add(NumericField('header_index', Field.Store.YES, True).setIntValue(fields["header_index"]))
+            doc.add(NumericField("header_span", Field.Store.YES, True)\
+                    .setIntValue('header_span' in fields and fields['header_span'] or 1))
+            doc.add(Field('header_type', fields["header_type"], Field.Store.YES, Field.Index.NOT_ANALYZED))
+
+            doc.add(Field('content', fields["content"], Field.Store.NO, Field.Index.ANALYZED, \
+                          Field.TermVector.WITH_POSITIONS_OFFSETS))
+
+            snip_pos = snippets.add(fields["content"])
+            doc.add(NumericField("snippets_position", Field.Store.YES, True).setIntValue(snip_pos[0]))
+            doc.add(NumericField("snippets_length", Field.Store.YES, True).setIntValue(snip_pos[1]))
+
+            if 'fragment_anchor' in fields:
+                doc.add(Field("fragment_anchor", fields['fragment_anchor'],
                               Field.Store.YES, Field.Index.NOT_ANALYZED))
                               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()
-        return self
+            if 'themes' in fields:
+                themes, themes_pl = zip(*[
+                    (Field("themes", theme, Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS),
+                     Field("themes_pl", theme, Field.Store.NO, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS))
+                     for theme in fields['themes']])
 
 
-    def __exit__(self, type, value, tb):
-        self.close()
+                themes = self.add_gaps(themes, 'themes')
+                themes_pl = self.add_gaps(themes_pl, 'themes_pl')
+
+                for t in themes:
+                    doc.add(t)
+                for t in themes_pl:
+                    doc.add(t)
+
+            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:
+            for header, position in zip(list(master), range(len(master))):
+
+                if header.tag in self.skip_header_tags:
+                    continue
+
+                content = u' '.join([t for t in header.itertext()])
+                content = fix_format(content)
+
+                doc = add_part(snippets, header_index=position, header_type=header.tag, content=content)
+
+                self.index.addDocument(doc)
+
+                for start, end in walker(header):
+                    if start is not None and start.tag == 'begin':
+                        fid = start.attrib['id'][1:]
+                        fragments[fid] = {'content': [], 'themes': [], 'start_section': position, 'start_header': header.tag}
+                        fragments[fid]['content'].append(start.tail)
+                    elif start is not None and start.tag == 'motyw':
+                        fid = start.attrib['id'][1:]
+                        if start.text is not None:
+                            fragments[fid]['themes'] += map(str.strip, map(give_me_utf8, start.text.split(',')))
+                        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]
+                        if frag['themes'] == []:
+                            continue  # empty themes list.
+                        del fragments[fid]
+
+                        def jstr(l):
+                            return u' '.join(map(
+                                lambda x: x == None and u'(none)' or unicode(x),
+                                l))
+
+                        doc = add_part(snippets,
+                                       header_type=frag['start_header'],
+                                       header_index=frag['start_section'],
+                                       header_span=position - frag['start_section'] + 1,
+                                       fragment_anchor=fid,
+                                       content=u' '.join(filter(lambda s: s is not None, frag['content'])),
+                                       themes=frag['themes'])
+
+                        self.index.addDocument(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)
+        finally:
+            snippets.close()
+
+
+def log_exception_wrapper(f):
+    def _wrap(*a):
+        try:
+            f(*a)
+        except Exception, e:
+            print("Error in indexing thread: %s" % e)
+            traceback.print_exc()
+            raise e
+    return _wrap
 
 
 class ReusableIndex(Index):
 
 
 class ReusableIndex(Index):
@@ -250,30 +472,23 @@ class ReusableIndex(Index):
     if you cannot rely on atexit, use ReusableIndex.close_reusable() yourself.
     """
     index = None
     if you cannot rely on atexit, use ReusableIndex.close_reusable() yourself.
     """
     index = None
-    pool = None
-    pool_jobs = None
 
     def open(self, analyzer=None, threads=4):
         if ReusableIndex.index is not None:
             self.index = ReusableIndex.index
         else:
 
     def open(self, analyzer=None, threads=4):
         if ReusableIndex.index is not None:
             self.index = ReusableIndex.index
         else:
-            ReusableIndex.pool = ThreadPool(threads)
-            ReusableIndex.pool_jobs = []
+            print("opening index")
             Index.open(self, analyzer)
             ReusableIndex.index = self.index
             atexit.register(ReusableIndex.close_reusable)
 
             Index.open(self, analyzer)
             ReusableIndex.index = self.index
             atexit.register(ReusableIndex.close_reusable)
 
-    def index_book(self, *args, **kw):
-        job = ReusableIndex.pool.apply_async(Index.index_book, (self,)+ args, kw)
-        ReusableIndex.pool_jobs.append(job)
+    def index_book(self, *args, **kw):
+    #     job = ReusableIndex.pool.apply_async(log_exception_wrapper(Index.index_book), (self,) + args, kw)
+        ReusableIndex.pool_jobs.append(job)
 
     @staticmethod
     def close_reusable():
         if ReusableIndex.index is not None:
 
     @staticmethod
     def close_reusable():
         if ReusableIndex.index is not None:
-            for job in ReusableIndex.pool_jobs:
-                job.wait()
-            ReusableIndex.pool.close()
-
             ReusableIndex.index.optimize()
             ReusableIndex.index.close()
             ReusableIndex.index = None
             ReusableIndex.index.optimize()
             ReusableIndex.index.close()
             ReusableIndex.index = None
@@ -282,20 +497,13 @@ class ReusableIndex(Index):
         pass
 
 
         pass
 
 
-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"))
-
-    def query(self, query):
-        return self.parser.parse(query)
+class JoinSearch(object):
+    """
+    This mixin could be used to handle block join queries.
+    (currently unused)
+    """
+    def __init__(self, *args, **kw):
+        super(JoinSearch, self).__init__(*args, **kw)
 
     def wrapjoins(self, query, fields=[]):
         """
 
     def wrapjoins(self, query, fields=[]):
         """
@@ -320,125 +528,647 @@ class Search(IndexStore):
             return BlockJoinQuery(query, self.parent_filter,
                                   BlockJoinQuery.ScoreMode.Total)
 
             return BlockJoinQuery(query, self.parent_filter,
                                   BlockJoinQuery.ScoreMode.Total)
 
-    def simple_search(self, query, max_results=50):
-        """Returns (books, total_hits)
-        """
+    def bsearch(self, query, max_results=50):
+        q = self.query(query)
+        bjq = BlockJoinQuery(q, self.parent_filter, BlockJoinQuery.ScoreMode.Avg)
 
 
-        tops = self.searcher.search(self.query(query), max_results)
+        tops = self.searcher.search(bjq, 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)
 
         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 search(self, query, max_results=50):
-        query = self.query(query)
-        query = self.wrapjoins(query, ["content", "themes"])
 
 
-        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)
+class SearchResult(object):
+    def __init__(self, searcher, scoreDocs, score=None, how_found=None, snippets=None):
+        if score:
+            self.score = score
+        else:
+            self.score = scoreDocs.score
 
 
-    def bsearch(self, query, max_results=50):
-        q = self.query(query)
-        bjq = BlockJoinQuery(q, self.parent_filter, BlockJoinQuery.ScoreMode.Avg)
+        self._hits = []
+        self.hits = None  # processed hits
 
 
-        tops = self.searcher.search(bjq, max_results)
+        stored = searcher.doc(scoreDocs.doc)
+        self.book_id = int(stored.get("book_id"))
+
+        header_type = stored.get("header_type")
+        if not header_type:
+            return
+
+        sec = (header_type, int(stored.get("header_index")))
+        header_span = stored.get('header_span')
+        header_span = header_span is not None and int(header_span) or 1
+
+        fragment = stored.get("fragment_anchor")
+
+        hit = (sec + (header_span,), fragment, scoreDocs.score, {'how_found': how_found, 'snippets': snippets and [snippets] or []})
+
+        self._hits.append(hit)
+
+    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 get_book(self):
+        return catalogue.models.Book.objects.get(id=self.book_id)
+
+    book = property(get_book)
+
+    def process_hits(self):
+        POSITION = 0
+        FRAGMENT = 1
+        POSITION_INDEX = 1
+        POSITION_SPAN = 2
+        SCORE = 2
+        OTHER = 3
+
+        # to sections and fragments
+        frags = filter(lambda r: r[FRAGMENT] is not None, self._hits)
+        sect = filter(lambda r: r[FRAGMENT] is None, self._hits)
+        sect = filter(lambda s: 0 == len(filter(
+            lambda f: s[POSITION][POSITION_INDEX] >= f[POSITION][POSITION_INDEX]
+            and s[POSITION][POSITION_INDEX] < f[POSITION][POSITION_INDEX] + f[POSITION][POSITION_SPAN],
+            frags)), sect)
+
+        hits = []
+
+        # remove duplicate fragments
+        fragments = {}
+        for f in frags:
+            fid = f[FRAGMENT]
+            if fid in fragments:
+                if fragments[fid][SCORE] >= f[SCORE]:
+                    continue
+            fragments[fid] = f
+        frags = fragments.values()
+
+        # remove duplicate sections
+        sections = {}
+
+        for s in sect:
+            si = s[POSITION][POSITION_INDEX]
+            # skip existing
+            if si in sections:
+                if sections[si]['score'] >= s[SCORE]:
+                    continue
+
+            m = {'score': s[SCORE],
+                 'section_number': s[POSITION][POSITION_INDEX] + 1,
+                 }
+            m.update(s[OTHER])
+            sections[si] = m
+
+        hits = sections.values()
+
+        for f in frags:
+            frag = catalogue.models.Fragment.objects.get(anchor=f[FRAGMENT])
+            m = {'score': f[SCORE],
+                 'fragment': frag,
+                 'themes': frag.tags.filter(category='theme')
+                 }
+            m.update(f[OTHER])
+            hits.append(m)
+
+        hits.sort(lambda a, b: cmp(a['score'], b['score']), reverse=True)
+
+        self.hits = hits
+
+        return self
+
+    def __unicode__(self):
+        return u'SearchResult(book_id=%d, score=%d)' % (self.book_id, self.score)
+
+    @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)
+                    #print(u"already have one with score %f, and this one has score %f" % (books[book.id][0], found.score))
+                else:
+                    books[r.book_id] = r
+        return books.values()
+
+    def __cmp__(self, other):
+        return cmp(self.score, other.score)
+
+
+class Hint(object):
+    """
+    Given some hint information (information we already know about)
+    our search target - like author, title (specific book), epoch, genre, kind
+    we can narrow down search using filters.
+    """
+    def __init__(self, search):
+        """
+        Accepts a Searcher instance.
+        """
+        self.search = search
+        self.book_tags = {}
+        self.part_tags = []
+        self._books = []
+
+    def books(self, *books):
+        """
+        Give a hint that we search these books.
+        """
+        self._books = books
+
+    def tags(self, tags):
+        """
+        Give a hint that these Tag objects (a list of)
+        is necessary.
+        """
+        for t in tags:
+            if t.category in ['author', 'title', 'epoch', 'genre', 'kind']:
+                lst = self.book_tags.get(t.category, [])
+                lst.append(t)
+                self.book_tags[t.category] = lst
+            if t.category in ['theme', 'theme_pl']:
+                self.part_tags.append(t)
+
+    def tag_filter(self, tags, field='tags'):
+        """
+        Given a lsit of tags and an optional field (but they are normally in tags field)
+        returns a filter accepting only books with specific tags.
+        """
+        q = BooleanQuery()
+
+        for tag in tags:
+            toks = self.search.get_tokens(tag.name, field=field)
+            tag_phrase = PhraseQuery()
+            for tok in toks:
+                tag_phrase.add(Term(field, tok))
+            q.add(BooleanClause(tag_phrase, BooleanClause.Occur.MUST))
+
+        return QueryWrapperFilter(q)
+
+    def book_filter(self):
+        """
+        Filters using book tags (all tag kinds except a theme)
+        """
+        tags = reduce(lambda a, b: a + b, self.book_tags.values(), [])
+        if tags:
+            return self.tag_filter(tags)
+        else:
+            return None
+
+    def part_filter(self):
+        """
+        This filter can be used to look for book parts.
+        It filters on book id and/or themes.
+        """
+        fs = []
+        if self.part_tags:
+            fs.append(self.tag_filter(self.part_tags, field='themes'))
+
+        if self._books != []:
+            bf = BooleanFilter()
+            for b in self._books:
+                id_filter = NumericRangeFilter.newIntRange('book_id', b.id, b.id, True, True)
+                bf.add(FilterClause(id_filter, BooleanClause.Occur.SHOULD))
+            fs.append(bf)
+
+        return Search.chain_filters(fs)
+
+    def should_search_for_book(self):
+        return self._books == []
+
+    def just_search_in(self, all):
+        """Holds logic to figure out which indexes should be search, when we have some hinst already"""
+        some = []
+        for field in all:
+            if field == 'authors' and 'author' in self.book_tags:
+                continue
+            if field == 'title' and self._books != []:
+                continue
+            if (field == 'themes' or field == 'themes_pl') and self.part_tags:
+                continue
+            some.append(field)
+        return some
+
+
+class Search(IndexStore):
+    """
+    Search facilities.
+    """
+    def __init__(self, default_field="content"):
+        IndexStore.__init__(self)
+        self.analyzer = WLAnalyzer()  # 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"))
+
+    def query(self, query):
+        """Parse query in default Lucene Syntax. (for humans)
+        """
+        return self.parser.parse(query)
+
+    def simple_search(self, query, max_results=50):
+        """Runs a query for books using lucene syntax. (for humans)
+        Returns (books, total_hits)
+        """
+
+        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)
 
         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)
 
-# TokenStream tokenStream = analyzer.tokenStream(fieldName, reader);
-# OffsetAttribute offsetAttribute = tokenStream.getAttribute(OffsetAttribute.class);
-# CharTermAttribute charTermAttribute = tokenStream.getAttribute(CharTermAttribute.class);
-
-# while (tokenStream.incrementToken()) {
-#     int startOffset = offsetAttribute.startOffset();
-#     int endOffset = offsetAttribute.endOffset();
-#     String term = charTermAttribute.toString();
-# }
-
+    def get_tokens(self, searched, field='content'):
+        """returns tokens analyzed by a proper (for a field) analyzer
+        argument can be: StringReader, string/unicode, or tokens. In the last case
+        they will just be returned (so we can reuse tokens, if we don't change the analyzer)
+        """
+        if isinstance(searched, str) or isinstance(searched, unicode):
+            searched = StringReader(searched)
+        elif isinstance(searched, list):
+            return searched
 
 
-class MultiSearch(Search):
-    """Class capable of IMDb-like searching"""
-    def get_tokens(self, queryreader):
-        if isinstance(queryreader, str):
-            queryreader = StringReader(queryreader)
-        queryreader.reset()
-        tokens = self.analyzer.reusableTokenStream('content', queryreader)
+        searched.reset()
+        tokens = self.analyzer.reusableTokenStream(field, searched)
         toks = []
         while tokens.incrementToken():
             cta = tokens.getAttribute(CharTermAttribute.class_)
         toks = []
         while tokens.incrementToken():
             cta = tokens.getAttribute(CharTermAttribute.class_)
-            toks.append(cta)
+            toks.append(cta.toString())
         return toks
 
         return toks
 
-    def make_phrase(self, tokens, field='content', joined=False):
-        phrase = PhraseQuery()
-        for t in tokens:
-            term = Term(field, t)
-            phrase.add(term)
-        if joined:
-            phrase = self.content_query(phrase)
+    def fuzziness(self, fuzzy):
+        """Helper method to sanitize fuzziness"""
+        if not fuzzy:
+            return None
+        if isinstance(fuzzy, float) and fuzzy > 0.0 and fuzzy <= 1.0:
+            return fuzzy
+        else:
+            return 0.5
+
+    def make_phrase(self, tokens, field='content', slop=2, fuzzy=False):
+        """
+        Return a PhraseQuery with a series of tokens.
+        """
+        if fuzzy:
+            phrase = MultiPhraseQuery()
+            for t in tokens:
+                term = Term(field, t)
+                fuzzterm = FuzzyTermEnum(self.searcher.getIndexReader(), term, self.fuzziness(fuzzy))
+                fuzzterms = []
+
+                while True:
+                    #                    print("fuzz %s" % unicode(fuzzterm.term()).encode('utf-8'))
+                    ft = fuzzterm.term()
+                    if ft:
+                        fuzzterms.append(ft)
+                    if not fuzzterm.next(): break
+                if fuzzterms:
+                    phrase.add(JArray('object')(fuzzterms, Term))
+                else:
+                    phrase.add(term)
+        else:
+            phrase = PhraseQuery()
+            phrase.setSlop(slop)
+            for t in tokens:
+                term = Term(field, t)
+                phrase.add(term)
         return phrase
 
         return phrase
 
-    def make_term_query(self, tokens, field='content', modal=BooleanClause.Occur.SHOULD, joined=False):
+    def make_term_query(self, tokens, field='content', modal=BooleanClause.Occur.SHOULD, fuzzy=False):
+        """
+        Returns term queries joined by boolean query.
+        modal - applies to boolean query
+        fuzzy - should the query by fuzzy.
+        """
         q = BooleanQuery()
         for t in tokens:
             term = Term(field, t)
         q = BooleanQuery()
         for t in tokens:
             term = Term(field, t)
+            if fuzzy:
+                term = FuzzyQuery(term, self.fuzziness(fuzzy))
+            else:
+                term = TermQuery(term)
             q.add(BooleanClause(term, modal))
             q.add(BooleanClause(term, modal))
-        if joined:
-            self.content_query(q)
         return q
 
         return q
 
-    def content_query(self, query):
-        return BlockJoinQuery(query, self.parent_filter,
-                              BlockJoinQuery.ScoreMode.Total)
+    def content_query(self, query):
+        return BlockJoinQuery(query, self.parent_filter,
+                              BlockJoinQuery.ScoreMode.Total)
 
 
-    def multiseach(self, query, max_results=50):
+    def search_perfect_book(self, searched, max_results=20, fuzzy=False, hint=None):
         """
         """
-        Search strategy:
-        - (phrase) OR -> content
-                      -> title
-                      -> author
-        - (keywords)  -> author
-                      -> motyw
-                      -> tags
-                      -> content
+        Search for perfect book matches. Just see if the query matches with some author or title,
+        taking hints into account.
         """
         """
-        queryreader = StringReader(query)
-        tokens = self.get_tokens(queryreader)
+        fields_to_search = ['authors', 'title']
+        only_in = None
+        if hint:
+            if not hint.should_search_for_book():
+                return []
+            fields_to_search = hint.just_search_in(fields_to_search)
+            only_in = hint.book_filter()
+
+        qrys = [self.make_phrase(self.get_tokens(searched, field=fld), field=fld, fuzzy=fuzzy) for fld in fields_to_search]
+
+        books = []
+        for q in qrys:
+            top = self.searcher.search(q,
+                self.chain_filters([only_in, self.term_filter(Term('is_book', 'true'))]),
+                max_results)
+            for found in top.scoreDocs:
+                books.append(SearchResult(self.searcher, found))
+        return books
+
+    def search_book(self, searched, max_results=20, fuzzy=False, hint=None):
+        fields_to_search = ['tags', 'authors', 'title']
+
+        only_in = None
+        if hint:
+            if not hint.should_search_for_book():
+                return []
+            fields_to_search = hint.just_search_in(fields_to_search)
+            only_in = hint.book_filter()
+
+        tokens = self.get_tokens(searched, field='SIMPLE')
 
 
-        top_level = BooleanQuery()
-        Should = BooleanClause.Occur.SHOULD
+        q = BooleanQuery()
+
+        for fld in fields_to_search:
+            q.add(BooleanClause(self.make_term_query(tokens, field=fld,
+                                fuzzy=fuzzy), BooleanClause.Occur.SHOULD))
+
+        books = []
+        top = self.searcher.search(q,
+                                   self.chain_filters([only_in, self.term_filter(Term('is_book', 'true'))]),
+            max_results)
+        for found in top.scoreDocs:
+            books.append(SearchResult(self.searcher, found))
+
+        return books
+
+    def search_perfect_parts(self, searched, max_results=20, fuzzy=False, hint=None):
+        """
+        Search for book parts which containt a phrase perfectly matching (with a slop of 2, default for make_phrase())
+        some part/fragment of the book.
+        """
+        qrys = [self.make_phrase(self.get_tokens(searched), field=fld, fuzzy=fuzzy) for fld in ['content']]
+
+        flt = None
+        if hint:
+            flt = hint.part_filter()
+
+        books = []
+        for q in qrys:
+            top = self.searcher.search(q,
+                                       self.chain_filters([self.term_filter(Term('is_book', 'true'), inverse=True),
+                                                           flt]),
+                                       max_results)
+            for found in top.scoreDocs:
+                books.append(SearchResult(self.searcher, found, snippets=self.get_snippets(found, q)))
+
+        return books
+
+    def search_everywhere(self, searched, max_results=20, fuzzy=False, hint=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 = []
+        only_in = None
+
+        if hint:
+            only_in = hint.part_filter()
+
+        # content only query : themes x content
+        q = BooleanQuery()
+
+        tokens_pl = self.get_tokens(searched, field='content')
+        tokens = self.get_tokens(searched, field='SIMPLE')
+
+        # only search in themes when we do not already filter by themes
+        if hint is None or hint.just_search_in(['themes']) != []:
+            q.add(BooleanClause(self.make_term_query(tokens_pl, field='themes_pl',
+                                                     fuzzy=fuzzy), BooleanClause.Occur.MUST))
+
+        q.add(BooleanClause(self.make_term_query(tokens_pl, field='content',
+                                                 fuzzy=fuzzy), BooleanClause.Occur.SHOULD))
+
+        topDocs = self.searcher.search(q, only_in, max_results)
+        for found in topDocs.scoreDocs:
+            books.append(SearchResult(self.searcher, found))
+            print "* %s theme x content: %s" % (searched, books[-1]._hits)
+
+        # query themes/content x author/title/tags
+        q = BooleanQuery()
+        in_content = BooleanQuery()
+        in_meta = BooleanQuery()
+
+        for fld in ['themes_pl', 'content']:
+            in_content.add(BooleanClause(self.make_term_query(tokens_pl, field=fld, fuzzy=False), BooleanClause.Occur.SHOULD))
+
+        for fld in ['tags', 'authors', 'title']:
+            in_meta.add(BooleanClause(self.make_term_query(tokens, field=fld, fuzzy=False), BooleanClause.Occur.SHOULD))
+
+        q.add(BooleanClause(in_content, BooleanClause.Occur.MUST))
+        q.add(BooleanClause(in_meta, BooleanClause.Occur.SHOULD))
+
+        topDocs = self.searcher.search(q, only_in, max_results)
+        for found in topDocs.scoreDocs:
+            books.append(SearchResult(self.searcher, found))
+            print "* %s scatter search: %s" % (searched, books[-1]._hits)
+
+        return books
+
+    # def multisearch(self, query, max_results=50):
+    #     """
+    #     Search strategy:
+    #     - (phrase) OR -> content
+    #                   -> title
+    #                   -> authors
+    #     - (keywords)  -> authors
+    #                   -> motyw
+    #                   -> tags
+    #                   -> content
+    #     """
+        # queryreader = StringReader(query)
+        # tokens = self.get_tokens(queryreader)
+
+        # top_level = BooleanQuery()
+        # Should = BooleanClause.Occur.SHOULD
+
+        # phrase_level = BooleanQuery()
+        # phrase_level.setBoost(1.3)
+
+        # p_content = self.make_phrase(tokens, joined=True)
+        # p_title = self.make_phrase(tokens, 'title')
+        # p_author = self.make_phrase(tokens, 'author')
+
+        # phrase_level.add(BooleanClause(p_content, Should))
+        # phrase_level.add(BooleanClause(p_title, Should))
+        # phrase_level.add(BooleanClause(p_author, Should))
+
+        # kw_level = BooleanQuery()
+
+        # kw_level.add(self.make_term_query(tokens, 'author'), Should)
+        # j_themes = self.make_term_query(tokens, 'themes', joined=True)
+        # kw_level.add(j_themes, Should)
+        # kw_level.add(self.make_term_query(tokens, 'tags'), Should)
+        # j_con = self.make_term_query(tokens, joined=True)
+        # kw_level.add(j_con, Should)
+
+        # top_level.add(BooleanClause(phrase_level, Should))
+        # top_level.add(BooleanClause(kw_level, Should))
+
+        # return None
+
+    def get_snippets(self, scoreDoc, query, field='content'):
+        """
+        Returns a snippet for found scoreDoc.
+        """
+        htmlFormatter = SimpleHTMLFormatter()
+        highlighter = Highlighter(htmlFormatter, QueryScorer(query))
 
 
-        phrase_level = BooleanQuery()
+        stored = self.searcher.doc(scoreDoc.doc)
 
 
-        p_content = self.make_phrase(tokens, joined=True)
-        p_title = self.make_phrase(tokens, 'title')
-        p_author = self.make_phrase(tokens, 'author')
+        # locate content.
+        snippets = Snippets(stored.get('book_id')).open()
+        try:
+            text = snippets.get((int(stored.get('snippets_position')),
+                                 int(stored.get('snippets_length'))))
+        finally:
+            snippets.close()
+
+        tokenStream = TokenSources.getAnyTokenStream(self.searcher.getIndexReader(), scoreDoc.doc, field, self.analyzer)
+        #  highlighter.getBestTextFragments(tokenStream, text, False, 10)
+        snip = highlighter.getBestFragments(tokenStream, text, 3, "...")
+
+        return snip
+
+    @staticmethod
+    def enum_to_array(enum):
+        """
+        Converts a lucene TermEnum to array of Terms, suitable for
+        addition to queries
+        """
+        terms = []
+
+        while True:
+            t = enum.term()
+            if t:
+                terms.append(t)
+            if not enum.next(): break
 
 
-        phrase_level.add(BooleanClause(p_content, Should))
-        phrase_level.add(BooleanClause(p_title, Should))
-        phrase_level.add(BooleanClause(p_author, Should))
+        if terms:
+            return JArray('object')(terms, Term)
 
 
-        kw_level = BooleanQuery()
+    def search_tags(self, query, filter=None, max_results=40):
+        """
+        Search for Tag objects using query.
+        """
+        tops = self.searcher.search(query, filter, max_results)
 
 
-        kw_level.add(self.make_term_query(tokens, 'author'), Should)
-        kw_level.add(self.make_term_query(tokens, 'themes', joined=True), Should)
-        kw_level.add(self.make_term_query(tokens, 'tags'), Should)
-        kw_level.add(self.make_term_query(tokens, joined=True), Should)
+        tags = []
+        for found in tops.scoreDocs:
+            doc = self.searcher.doc(found.doc)
+            tag = catalogue.models.Tag.objects.get(id=doc.get("tag_id"))
+            tags.append(tag)
+            print "%s (%d) -> %f" % (tag, tag.id, found.score)
 
 
-        top_level.add(BooleanClause(phrase_level, Should))
-        top_level.add(BooleanClause(kw_level, Should))
+        return tags
 
 
-        tops = self.searcher.search(top_level, max_results)
+    def search_books(self, query, filter=None, max_results=10):
+        """
+        Searches for Book objects using query
+        """
         bks = []
         bks = []
+        tops = self.searcher.search(query, filter, max_results)
         for found in tops.scoreDocs:
             doc = self.searcher.doc(found.doc)
             bks.append(catalogue.models.Book.objects.get(id=doc.get("book_id")))
         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)
+        return bks
+
+    def create_prefix_phrase(self, toks, field):
+        q = MultiPhraseQuery()
+        for i in range(len(toks)):
+            t = Term(field, toks[i])
+            if i == len(toks) - 1:
+                pterms = Search.enum_to_array(PrefixTermEnum(self.searcher.getIndexReader(), t))
+                if pterms:
+                    q.add(pterms)
+                else:
+                    q.add(t)
+            else:
+                q.add(t)
+        return q
+
+    @staticmethod
+    def term_filter(term, inverse=False):
+        only_term = TermsFilter()
+        only_term.addTerm(term)
+
+        if inverse:
+            neg = BooleanFilter()
+            neg.add(FilterClause(only_term, BooleanClause.Occur.MUST_NOT))
+            only_term = neg
+
+        return only_term
+
+    def hint_tags(self, string, max_results=50):
+        """
+        Return auto-complete hints for tags
+        using prefix search.
+        """
+        toks = self.get_tokens(string, field='SIMPLE')
+        top = BooleanQuery()
+
+        for field in ['tag_name', 'tag_name_pl']:
+            q = self.create_prefix_phrase(toks, field)
+            top.add(BooleanClause(q, BooleanClause.Occur.SHOULD))
+
+        no_book_cat = self.term_filter(Term("tag_category", "book"), inverse=True)
+
+        return self.search_tags(top, no_book_cat, max_results=max_results)
+
+    def hint_books(self, string, max_results=50):
+        """
+        Returns auto-complete hints for book titles
+        Because we do not index 'pseudo' title-tags.
+        Prefix search.
+        """
+        toks = self.get_tokens(string, field='SIMPLE')
+
+        q = self.create_prefix_phrase(toks, 'title')
+
+        return self.search_books(q, self.term_filter(Term("is_book", "true")), max_results=max_results)
+
+    @staticmethod
+    def chain_filters(filters, op=ChainedFilter.AND):
+        """
+        Chains a filter list together
+        """
+        filters = filter(lambda x: x is not None, filters)
+        if not filters:
+            return None
+        chf = ChainedFilter(JArray('object')(filters, Filter), op)
+        return chf
+
+    def filtered_categories(self, tags):
+        """
+        Return a list of tag categories, present in tags list.
+        """
+        cats = {}
+        for t in tags:
+            cats[t.category] = True
+        return cats.keys()
+
+    def hint(self):
+        return Hint(self)