fix impovement for IT #3356 - workaround rare problem
[librarian.git] / librarian / epub.py
1 # -*- coding: utf-8 -*-
2 #
3 # This file is part of Librarian, licensed under GNU Affero GPLv3 or later.
4 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
5 #
6 from __future__ import with_statement
7
8 import os
9 import os.path
10 import re
11 import subprocess
12 from StringIO import StringIO
13 from copy import deepcopy
14 from lxml import etree
15 import zipfile
16 from tempfile import mkdtemp, NamedTemporaryFile
17 from shutil import rmtree
18
19 from librarian import RDFNS, WLNS, NCXNS, OPFNS, XHTMLNS, DCNS, OutputFile
20 from librarian.cover import DefaultEbookCover
21
22 from librarian import functions, get_resource
23
24 from librarian.hyphenator import Hyphenator
25
26 functions.reg_person_name()
27 functions.reg_lang_code_3to2()
28
29 def set_hyph_language(source_tree):
30     def get_short_lng_code(text):
31         result = ''
32         text = ''.join(text)
33         with open(get_resource('res/ISO-639-2_8859-1.txt'), 'rb') as f:
34             for line in f:
35                 list = line.strip().split('|')
36                 if list[0] == text:
37                     result=list[2]
38         if result == '':
39             return text
40         else:
41             return result
42     bibl_lng = etree.XPath('//dc:language//text()', namespaces = {'dc':str(DCNS)})(source_tree)
43     short_lng = get_short_lng_code(bibl_lng[0])   
44     try:
45         return Hyphenator(get_resource('res/hyph-dictionaries/hyph_' + short_lng + '.dic'))
46     except:
47         pass
48     
49 def hyphenate_and_fix_conjunctions(source_tree, hyph):
50     if hyph is not None:
51         texts = etree.XPath('/utwor/*[2]//text()')(source_tree)
52         for t in texts:
53             parent = t.getparent()
54             newt = ''
55             wlist = re.compile(r'\w+|[^\w]', re.UNICODE).findall(t)
56             for w in wlist:
57                 newt += hyph.inserted(w, u'\u00AD')       
58             newt = re.sub(r'(?<=\s\w)\s+', u'\u00A0', newt)
59             if t.is_text:
60                 parent.text = newt
61             elif t.is_tail:
62                 parent.tail = newt
63         
64 def inner_xml(node):
65     """ returns node's text and children as a string
66
67     >>> print inner_xml(etree.fromstring('<a>x<b>y</b>z</a>'))
68     x<b>y</b>z
69     """
70
71     nt = node.text if node.text is not None else ''
72     return ''.join([nt] + [etree.tostring(child) for child in node])
73
74 def set_inner_xml(node, text):
75     """ sets node's text and children from a string
76
77     >>> e = etree.fromstring('<a>b<b>x</b>x</a>')
78     >>> set_inner_xml(e, 'x<b>y</b>z')
79     >>> print etree.tostring(e)
80     <a>x<b>y</b>z</a>
81     """
82
83     p = etree.fromstring('<x>%s</x>' % text)
84     node.text = p.text
85     node[:] = p[:]
86
87
88 def node_name(node):
89     """ Find out a node's name
90
91     >>> print node_name(etree.fromstring('<a>X<b>Y</b>Z</a>'))
92     XYZ
93     """
94
95     tempnode = deepcopy(node)
96
97     for p in ('pe', 'pa', 'pt', 'pr', 'motyw'):
98         for e in tempnode.findall('.//%s' % p):
99             t = e.tail
100             e.clear()
101             e.tail = t
102     etree.strip_tags(tempnode, '*')
103     return tempnode.text
104
105
106 def xslt(xml, sheet):
107     if isinstance(xml, etree._Element):
108         xml = etree.ElementTree(xml)
109     with open(sheet) as xsltf:
110         return xml.xslt(etree.parse(xsltf))
111
112
113 def replace_characters(node):
114     def replace_chars(text):
115         if text is None:
116             return None
117         return text.replace(u"\ufeff", u"")\
118                    .replace("---", u"\u2014")\
119                    .replace("--", u"\u2013")\
120                    .replace(",,", u"\u201E")\
121                    .replace('"', u"\u201D")\
122                    .replace("'", u"\u2019")
123     if node.tag in ('uwaga', 'extra'):
124         t = node.tail
125         node.clear()
126         node.tail = t
127     node.text = replace_chars(node.text)
128     node.tail = replace_chars(node.tail)
129     for child in node:
130         replace_characters(child)
131
132
133 def find_annotations(annotations, source, part_no):
134     for child in source:
135         if child.tag in ('pe', 'pa', 'pt', 'pr'):
136             annotation = deepcopy(child)
137             number = str(len(annotations)+1)
138             annotation.set('number', number)
139             annotation.set('part', str(part_no))
140             annotation.tail = ''
141             annotations.append(annotation)
142             tail = child.tail
143             child.clear()
144             child.tail = tail
145             child.text = number
146         if child.tag not in ('extra', 'uwaga'):
147             find_annotations(annotations, child, part_no)
148
149
150 class Stanza(object):
151     """
152     Converts / verse endings into verse elements in a stanza.
153
154     Slashes may only occur directly in the stanza. Any slashes in subelements
155     will be ignored, and the subelements will be put inside verse elements.
156
157     >>> s = etree.fromstring("<strofa>a <b>c</b> <b>c</b>/\\nb<x>x/\\ny</x>c/ \\nd</strofa>")
158     >>> Stanza(s).versify()
159     >>> print etree.tostring(s)
160     <strofa><wers_normalny>a <b>c</b> <b>c</b></wers_normalny><wers_normalny>b<x>x/
161     y</x>c</wers_normalny><wers_normalny>d</wers_normalny></strofa>
162     
163     """
164     def __init__(self, stanza_elem):
165         self.stanza = stanza_elem
166         self.verses = []
167         self.open_verse = None
168
169     def versify(self):
170         self.push_text(self.stanza.text)
171         for elem in self.stanza:
172             self.push_elem(elem)
173             self.push_text(elem.tail)
174         tail = self.stanza.tail
175         self.stanza.clear()
176         self.stanza.tail = tail
177         self.stanza.extend(self.verses)
178
179     def open_normal_verse(self):
180         self.open_verse = self.stanza.makeelement("wers_normalny")
181         self.verses.append(self.open_verse)
182
183     def get_open_verse(self):
184         if self.open_verse is None:
185             self.open_normal_verse()
186         return self.open_verse
187
188     def push_text(self, text):
189         if not text:
190             return
191         for i, verse_text in enumerate(re.split(r"/\s*\n", text)):
192             if i:
193                 self.open_normal_verse()
194             verse = self.get_open_verse()
195             if len(verse):
196                 verse[-1].tail = (verse[-1].tail or "") + verse_text
197             else:
198                 verse.text = (verse.text or "") + verse_text
199
200     def push_elem(self, elem):
201         if elem.tag.startswith("wers"):
202             verse = deepcopy(elem)
203             verse.tail = None
204             self.verses.append(verse)
205             self.open_verse = verse
206         else:
207             appended = deepcopy(elem)
208             appended.tail = None
209             self.get_open_verse().append(appended)
210
211
212 def replace_by_verse(tree):
213     """ Find stanzas and create new verses in place of a '/' character """
214
215     stanzas = tree.findall('.//' + WLNS('strofa'))
216     for stanza in stanzas:
217         Stanza(stanza).versify()
218
219
220 def add_to_manifest(manifest, partno):
221     """ Adds a node to the manifest section in content.opf file """
222
223     partstr = 'part%d' % partno
224     e = manifest.makeelement(OPFNS('item'), attrib={
225                                  'id': partstr,
226                                  'href': partstr + '.html',
227                                  'media-type': 'application/xhtml+xml',
228                              })
229     manifest.append(e)
230
231
232 def add_to_spine(spine, partno):
233     """ Adds a node to the spine section in content.opf file """
234
235     e = spine.makeelement(OPFNS('itemref'), attrib={'idref': 'part%d' % partno});
236     spine.append(e)
237
238
239 class TOC(object):
240     def __init__(self, name=None, part_href=None):
241         self.children = []
242         self.name = name
243         self.part_href = part_href
244         self.sub_number = None
245
246     def add(self, name, part_href, level=0, is_part=True, index=None):
247         assert level == 0 or index is None
248         if level > 0 and self.children:
249             return self.children[-1].add(name, part_href, level-1, is_part)
250         else:
251             t = TOC(name)
252             t.part_href = part_href
253             if index is not None:
254                 self.children.insert(index, t)
255             else:
256                 self.children.append(t)
257             if not is_part:
258                 t.sub_number = len(self.children) + 1
259                 return t.sub_number
260
261     def append(self, toc):
262         self.children.append(toc)
263
264     def extend(self, toc):
265         self.children.extend(toc.children)
266
267     def depth(self):
268         if self.children:
269             return max((c.depth() for c in self.children)) + 1
270         else:
271             return 0
272
273     def href(self):
274         src = self.part_href
275         if self.sub_number is not None:
276             src += '#sub%d' % self.sub_number
277         return src
278
279     def write_to_xml(self, nav_map, counter=1):
280         for child in self.children:
281             nav_point = nav_map.makeelement(NCXNS('navPoint'))
282             nav_point.set('id', 'NavPoint-%d' % counter)
283             nav_point.set('playOrder', str(counter))
284
285             nav_label = nav_map.makeelement(NCXNS('navLabel'))
286             text = nav_map.makeelement(NCXNS('text'))
287             if child.name is not None:
288                 text.text = re.sub(r'\n', ' ', child.name)
289             else:
290                 text.text = child.name
291             nav_label.append(text)
292             nav_point.append(nav_label)
293
294             content = nav_map.makeelement(NCXNS('content'))
295             content.set('src', child.href())
296             nav_point.append(content)
297             nav_map.append(nav_point)
298             counter = child.write_to_xml(nav_point, counter + 1)
299         return counter
300
301     def html_part(self, depth=0):
302         texts = []
303         for child in self.children:
304             texts.append(
305                 "<div style='margin-left:%dem;'><a href='%s'>%s</a></div>" %
306                 (depth, child.href(), child.name))
307             texts.append(child.html_part(depth+1))
308         return "\n".join(texts)
309
310     def html(self):
311         with open(get_resource('epub/toc.html')) as f:
312             t = unicode(f.read(), 'utf-8')
313         return t % self.html_part()
314
315
316 def used_chars(element):
317     """ Lists characters used in an ETree Element """
318     chars = set((element.text or '') + (element.tail or ''))
319     for child in element:
320         chars = chars.union(used_chars(child))
321     return chars
322
323
324 def chop(main_text):
325     """ divide main content of the XML file into chunks """
326
327     # prepare a container for each chunk
328     part_xml = etree.Element('utwor')
329     etree.SubElement(part_xml, 'master')
330     main_xml_part = part_xml[0] # master
331
332     last_node_part = False
333     
334     # the below loop are workaround for a problem with epubs in drama ebooks without acts
335     is_scene = False
336     is_act = False
337     for one_part in main_text:
338         name = one_part.tag
339         if name == 'naglowek_scena':
340             is_scene = True
341         elif name == 'naglowek_akt':
342             is_act = True
343     
344     for one_part in main_text:
345         name = one_part.tag
346         if is_act is False and is_scene is True:
347             if name == 'naglowek_czesc':
348                 yield part_xml
349                 last_node_part = True
350                 main_xml_part[:] = [deepcopy(one_part)]
351             elif not last_node_part and name == "naglowek_scena":
352                 yield part_xml
353                 main_xml_part[:] = [deepcopy(one_part)]
354             else:
355                 main_xml_part.append(deepcopy(one_part))
356                 last_node_part = False
357         else:
358             if name == 'naglowek_czesc':
359                 yield part_xml
360                 last_node_part = True
361                 main_xml_part[:] = [deepcopy(one_part)]
362             elif not last_node_part and name in ("naglowek_rozdzial", "naglowek_akt", "srodtytul"):
363                 yield part_xml
364                 main_xml_part[:] = [deepcopy(one_part)]
365             else:
366                 main_xml_part.append(deepcopy(one_part))
367                 last_node_part = False            
368     yield part_xml
369
370
371 def transform_chunk(chunk_xml, chunk_no, annotations, empty=False, _empty_html_static=[]):
372     """ transforms one chunk, returns a HTML string, a TOC object and a set of used characters """
373
374     toc = TOC()
375     for element in chunk_xml[0]:
376         if element.tag == "naglowek_czesc":
377             toc.add(node_name(element), "part%d.html#book-text" % chunk_no)
378         elif element.tag in ("naglowek_rozdzial", "naglowek_akt", "srodtytul"):
379             toc.add(node_name(element), "part%d.html" % chunk_no)
380         elif element.tag in ('naglowek_podrozdzial', 'naglowek_scena'):
381             subnumber = toc.add(node_name(element), "part%d.html" % chunk_no, level=1, is_part=False)
382             element.set('sub', str(subnumber))
383     if empty:
384         if not _empty_html_static:
385             _empty_html_static.append(open(get_resource('epub/emptyChunk.html')).read())
386         chars = set()
387         output_html = _empty_html_static[0]
388     else:
389         find_annotations(annotations, chunk_xml, chunk_no)
390         replace_by_verse(chunk_xml)
391         html_tree = xslt(chunk_xml, get_resource('epub/xsltScheme.xsl'))
392         chars = used_chars(html_tree.getroot())
393         output_html = etree.tostring(html_tree, method="html", pretty_print=True)
394     return output_html, toc, chars
395
396
397 def transform(wldoc, verbose=False,
398               style=None, html_toc=False,
399               sample=None, cover=None, flags=None):
400     """ produces a EPUB file
401
402     sample=n: generate sample e-book (with at least n paragraphs)
403     cover: a cover.Cover factory or True for default
404     flags: less-advertising, without-fonts, working-copy, with-full-fonts
405     """
406
407     def transform_file(wldoc, chunk_counter=1, first=True, sample=None):
408         """ processes one input file and proceeds to its children """
409
410         replace_characters(wldoc.edoc.getroot())
411         
412         hyphenator = set_hyph_language(wldoc.edoc.getroot())
413         hyphenate_and_fix_conjunctions(wldoc.edoc.getroot(), hyphenator)
414         
415         
416         # every input file will have a TOC entry,
417         # pointing to starting chunk
418         toc = TOC(wldoc.book_info.title, "part%d.html" % chunk_counter)
419         chars = set()
420         if first:
421             # write book title page
422             html_tree = xslt(wldoc.edoc, get_resource('epub/xsltTitle.xsl'))
423             chars = used_chars(html_tree.getroot())
424             zip.writestr('OPS/title.html',
425                  etree.tostring(html_tree, method="html", pretty_print=True))
426             # add a title page TOC entry
427             toc.add(u"Strona tytułowa", "title.html")
428         elif wldoc.book_info.parts:
429             # write title page for every parent
430             if sample is not None and sample <= 0:
431                 chars = set()
432                 html_string = open(get_resource('epub/emptyChunk.html')).read()
433             else:
434                 html_tree = xslt(wldoc.edoc, get_resource('epub/xsltChunkTitle.xsl'))
435                 chars = used_chars(html_tree.getroot())
436                 html_string = etree.tostring(html_tree, method="html", pretty_print=True)
437             zip.writestr('OPS/part%d.html' % chunk_counter, html_string)
438             add_to_manifest(manifest, chunk_counter)
439             add_to_spine(spine, chunk_counter)
440             chunk_counter += 1
441
442         if len(wldoc.edoc.getroot()) > 1:
443             # rdf before style master
444             main_text = wldoc.edoc.getroot()[1]
445         else:
446             # rdf in style master
447             main_text = wldoc.edoc.getroot()[0]
448             if main_text.tag == RDFNS('RDF'):
449                 main_text = None
450
451         if main_text is not None:
452             for chunk_xml in chop(main_text):
453                 empty = False
454                 if sample is not None:
455                     if sample <= 0:
456                         empty = True
457                     else:
458                         sample -= len(chunk_xml.xpath('//strofa|//akap|//akap_cd|//akap_dialog'))
459                 chunk_html, chunk_toc, chunk_chars = transform_chunk(chunk_xml, chunk_counter, annotations, empty)
460
461                 toc.extend(chunk_toc)
462                 chars = chars.union(chunk_chars)
463                 zip.writestr('OPS/part%d.html' % chunk_counter, chunk_html)
464                 add_to_manifest(manifest, chunk_counter)
465                 add_to_spine(spine, chunk_counter)
466                 chunk_counter += 1
467
468         for child in wldoc.parts():
469             child_toc, chunk_counter, chunk_chars, sample = transform_file(
470                 child, chunk_counter, first=False, sample=sample)
471             toc.append(child_toc)
472             chars = chars.union(chunk_chars)
473
474         return toc, chunk_counter, chars, sample
475
476
477     document = deepcopy(wldoc)
478     del wldoc
479
480     if flags:
481         for flag in flags:
482             document.edoc.getroot().set(flag, 'yes')
483
484     # add editors info
485     document.edoc.getroot().set('editors', u', '.join(sorted(
486         editor.readable() for editor in document.editors())))
487     if document.book_info.funders:
488         document.edoc.getroot().set('funders', u', '.join(
489             document.book_info.funders))
490     if document.book_info.thanks:
491         document.edoc.getroot().set('thanks', document.book_info.thanks)
492
493     opf = xslt(document.book_info.to_etree(), get_resource('epub/xsltContent.xsl'))
494     manifest = opf.find('.//' + OPFNS('manifest'))
495     guide = opf.find('.//' + OPFNS('guide'))
496     spine = opf.find('.//' + OPFNS('spine'))
497
498     output_file = NamedTemporaryFile(prefix='librarian', suffix='.epub', delete=False)
499     zip = zipfile.ZipFile(output_file, 'w', zipfile.ZIP_DEFLATED)
500
501     # write static elements
502     mime = zipfile.ZipInfo()
503     mime.filename = 'mimetype'
504     mime.compress_type = zipfile.ZIP_STORED
505     mime.extra = ''
506     zip.writestr(mime, 'application/epub+zip')
507     zip.writestr('META-INF/container.xml', '<?xml version="1.0" ?><container version="1.0" ' \
508                        'xmlns="urn:oasis:names:tc:opendocument:xmlns:container">' \
509                        '<rootfiles><rootfile full-path="OPS/content.opf" ' \
510                        'media-type="application/oebps-package+xml" />' \
511                        '</rootfiles></container>')
512     zip.write(get_resource('res/wl-logo-small.png'), os.path.join('OPS', 'logo_wolnelektury.png'))
513     zip.write(get_resource('res/jedenprocent.png'), os.path.join('OPS', 'jedenprocent.png'))
514     if not style:
515         style = get_resource('epub/style.css')
516     zip.write(style, os.path.join('OPS', 'style.css'))
517
518     if cover:
519         if cover is True:
520             cover = DefaultEbookCover
521
522         cover_file = StringIO()
523         bound_cover = cover(document.book_info)
524         bound_cover.save(cover_file)
525         cover_name = 'cover.%s' % bound_cover.ext()
526         zip.writestr(os.path.join('OPS', cover_name), cover_file.getvalue())
527         del cover_file
528
529         cover_tree = etree.parse(get_resource('epub/cover.html'))
530         cover_tree.find('//' + XHTMLNS('img')).set('src', cover_name)
531         zip.writestr('OPS/cover.html', etree.tostring(
532                         cover_tree, method="html", pretty_print=True))
533
534         if bound_cover.uses_dc_cover:
535             if document.book_info.cover_by:
536                 document.edoc.getroot().set('data-cover-by', document.book_info.cover_by)
537             if document.book_info.cover_source:
538                 document.edoc.getroot().set('data-cover-source', document.book_info.cover_source)
539
540         manifest.append(etree.fromstring(
541             '<item id="cover" href="cover.html" media-type="application/xhtml+xml" />'))
542         manifest.append(etree.fromstring(
543             '<item id="cover-image" href="%s" media-type="%s" />' % (cover_name, bound_cover.mime_type())))
544         spine.insert(0, etree.fromstring('<itemref idref="cover"/>'))
545         opf.getroot()[0].append(etree.fromstring('<meta name="cover" content="cover-image"/>'))
546         guide.append(etree.fromstring('<reference href="cover.html" type="cover" title="Okładka"/>'))
547
548
549     annotations = etree.Element('annotations')
550
551     toc_file = etree.fromstring('<?xml version="1.0" encoding="utf-8"?><!DOCTYPE ncx PUBLIC ' \
552                                '"-//NISO//DTD ncx 2005-1//EN" "http://www.daisy.org/z3986/2005/ncx-2005-1.dtd">' \
553                                '<ncx xmlns="http://www.daisy.org/z3986/2005/ncx/" xml:lang="pl" ' \
554                                'version="2005-1"><head></head><docTitle></docTitle><navMap>' \
555                                '</navMap></ncx>')
556     nav_map = toc_file[-1]
557
558     if html_toc:
559         manifest.append(etree.fromstring(
560             '<item id="html_toc" href="toc.html" media-type="application/xhtml+xml" />'))
561         spine.append(etree.fromstring(
562             '<itemref idref="html_toc" />'))
563         guide.append(etree.fromstring('<reference href="toc.html" type="toc" title="Spis treści"/>'))
564
565     toc, chunk_counter, chars, sample = transform_file(document, sample=sample)
566
567     if len(toc.children) < 2:
568         toc.add(u"Początek utworu", "part1.html")
569
570     # Last modifications in container files and EPUB creation
571     if len(annotations) > 0:
572         toc.add("Przypisy", "annotations.html")
573         manifest.append(etree.fromstring(
574             '<item id="annotations" href="annotations.html" media-type="application/xhtml+xml" />'))
575         spine.append(etree.fromstring(
576             '<itemref idref="annotations" />'))
577         replace_by_verse(annotations)
578         html_tree = xslt(annotations, get_resource('epub/xsltAnnotations.xsl'))
579         chars = chars.union(used_chars(html_tree.getroot()))
580         zip.writestr('OPS/annotations.html', etree.tostring(
581                             html_tree, method="html", pretty_print=True))
582
583     toc.add("Wesprzyj Wolne Lektury", "support.html")
584     manifest.append(etree.fromstring(
585         '<item id="support" href="support.html" media-type="application/xhtml+xml" />'))
586     spine.append(etree.fromstring(
587         '<itemref idref="support" />'))
588     html_string = open(get_resource('epub/support.html')).read()
589     chars.update(used_chars(etree.fromstring(html_string)))
590     zip.writestr('OPS/support.html', html_string)
591
592     toc.add("Strona redakcyjna", "last.html")
593     manifest.append(etree.fromstring(
594         '<item id="last" href="last.html" media-type="application/xhtml+xml" />'))
595     spine.append(etree.fromstring(
596         '<itemref idref="last" />'))
597     html_tree = xslt(document.edoc, get_resource('epub/xsltLast.xsl'))
598     chars.update(used_chars(html_tree.getroot()))
599     zip.writestr('OPS/last.html', etree.tostring(
600                         html_tree, method="html", pretty_print=True))
601
602     if not flags or not 'without-fonts' in flags:
603         # strip fonts
604         tmpdir = mkdtemp('-librarian-epub')
605         try:
606             cwd = os.getcwd()
607         except OSError:
608             cwd = None
609
610         os.chdir(os.path.join(os.path.dirname(os.path.realpath(__file__)), 'font-optimizer'))
611         for fname in 'DejaVuSerif.ttf', 'DejaVuSerif-Bold.ttf', 'DejaVuSerif-Italic.ttf', 'DejaVuSerif-BoldItalic.ttf':
612             if not flags or not 'with-full-fonts' in flags:
613                 optimizer_call = ['perl', 'subset.pl', '--chars', ''.join(chars).encode('utf-8'),
614                               get_resource('fonts/' + fname), os.path.join(tmpdir, fname)]              
615                 if verbose:
616                     print "Running font-optimizer"
617                     subprocess.check_call(optimizer_call)
618                 else:
619                     subprocess.check_call(optimizer_call, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
620                     zip.write(os.path.join(tmpdir, fname), os.path.join('OPS', fname))
621             else:
622                 zip.write(get_resource('fonts/' + fname), os.path.join('OPS', fname))
623             manifest.append(etree.fromstring(
624                 '<item id="%s" href="%s" media-type="application/x-font-truetype" />' % (fname, fname)))
625         rmtree(tmpdir)
626         if cwd is not None:
627             os.chdir(cwd)
628     zip.writestr('OPS/content.opf', etree.tostring(opf, pretty_print=True, xml_declaration = True, encoding='UTF-8'))
629     title = document.book_info.title
630     attributes = "dtb:uid", "dtb:depth", "dtb:totalPageCount", "dtb:maxPageNumber"
631     for st in attributes:
632         meta = toc_file.makeelement(NCXNS('meta'))
633         meta.set('name', st)
634         meta.set('content', '0')
635         toc_file[0].append(meta)
636     toc_file[0][0].set('content', str(document.book_info.url))
637     toc_file[0][1].set('content', str(toc.depth()))
638     set_inner_xml(toc_file[1], ''.join(('<text>', title, '</text>')))
639
640     # write TOC
641     if html_toc:
642         toc.add(u"Spis treści", "toc.html", index=1)
643         zip.writestr('OPS/toc.html', toc.html().encode('utf-8'))
644     toc.write_to_xml(nav_map)
645     zip.writestr('OPS/toc.ncx', etree.tostring(toc_file, pretty_print=True, xml_declaration = True, encoding='UTF-8'))
646     zip.close()
647
648     return OutputFile.from_filename(output_file.name)