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, OutputFile
  20 from librarian.cover import DefaultEbookCover
  21
  22 from librarian import functions, get_resource
  23
  24 functions.reg_person_name()
  25 functions.reg_lang_code_3to2()
  26
  27
  28 def inner_xml(node):
  29     """ returns node's text and children as a string
  30
  31     >>> print inner_xml(etree.fromstring('<a>x<b>y</b>z</a>'))
  32     x<b>y</b>z
  33     """
  34
  35     nt = node.text if node.text is not None else ''
  36     return ''.join([nt] + [etree.tostring(child) for child in node])
  37
  38 def set_inner_xml(node, text):
  39     """ sets node's text and children from a string
  40
  41     >>> e = etree.fromstring('<a>b<b>x</b>x</a>')
  42     >>> set_inner_xml(e, 'x<b>y</b>z')
  43     >>> print etree.tostring(e)
  44     <a>x<b>y</b>z</a>
  45     """
  46
  47     p = etree.fromstring('<x>%s</x>' % text)
  48     node.text = p.text
  49     node[:] = p[:]
  50
  51
  52 def node_name(node):
  53     """ Find out a node's name
  54
  55     >>> print node_name(etree.fromstring('<a>X<b>Y</b>Z</a>'))
  56     XYZ
  57     """
  58
  59     tempnode = deepcopy(node)
  60
  61     for p in ('pe', 'pa', 'pt', 'pr', 'motyw'):
  62         for e in tempnode.findall('.//%s' % p):
  63             t = e.tail
  64             e.clear()
  65             e.tail = t
  66     etree.strip_tags(tempnode, '*')
  67     return tempnode.text
  68
  69
  70 def xslt(xml, sheet):
  71     if isinstance(xml, etree._Element):
  72         xml = etree.ElementTree(xml)
  73     with open(sheet) as xsltf:
  74         return xml.xslt(etree.parse(xsltf))
  75
  76
  77 def replace_characters(node):
  78     def replace_chars(text):
  79         if text is None:
  80             return None
  81         #text = re.sub(r"(?<=\s\w)\s+", u"\u00a0", text) #fix for hanging single letter conjunctions – for future use.
  82         return text.replace(u"\ufeff", u"")\
  83                    .replace("---", u"\u2014")\
  84                    .replace("--", u"\u2013")\
  85                    .replace(",,", u"\u201E")\
  86                    .replace('"', u"\u201D")\
  87                    .replace("'", u"\u2019")
  88     if node.tag in ('uwaga', 'extra'):
  89         t = node.tail
  90         node.clear()
  91         node.tail = t
  92     node.text = replace_chars(node.text)
  93     node.tail = replace_chars(node.tail)
  94     for child in node:
  95         replace_characters(child)
  96
  97
  98 def find_annotations(annotations, source, part_no):
  99     for child in source:
 100         if child.tag in ('pe', 'pa', 'pt', 'pr'):
 101             annotation = deepcopy(child)
 102             number = str(len(annotations)+1)
 103             annotation.set('number', number)
 104             annotation.set('part', str(part_no))
 105             annotation.tail = ''
 106             annotations.append(annotation)
 107             tail = child.tail
 108             child.clear()
 109             child.tail = tail
 110             child.text = number
 111         if child.tag not in ('extra', 'uwaga'):
 112             find_annotations(annotations, child, part_no)
 113
 114
 115 class Stanza(object):
 116     """
 117     Converts / verse endings into verse elements in a stanza.
 118
 119     Slashes may only occur directly in the stanza. Any slashes in subelements
 120     will be ignored, and the subelements will be put inside verse elements.
 121
 122     >>> s = etree.fromstring("<strofa>a <b>c</b> <b>c</b>/\\nb<x>x/\\ny</x>c/ \\nd</strofa>")
 123     >>> Stanza(s).versify()
 124     >>> print etree.tostring(s)
 125     <strofa><wers_normalny>a <b>c</b> <b>c</b></wers_normalny><wers_normalny>b<x>x/
 126     y</x>c</wers_normalny><wers_normalny>d</wers_normalny></strofa>
 127
 128     """
 129     def __init__(self, stanza_elem):
 130         self.stanza = stanza_elem
 131         self.verses = []
 132         self.open_verse = None
 133
 134     def versify(self):
 135         self.push_text(self.stanza.text)
 136         for elem in self.stanza:
 137             self.push_elem(elem)
 138             self.push_text(elem.tail)
 139         tail = self.stanza.tail
 140         self.stanza.clear()
 141         self.stanza.tail = tail
 142         self.stanza.extend(self.verses)
 143
 144     def open_normal_verse(self):
 145         self.open_verse = self.stanza.makeelement("wers_normalny")
 146         self.verses.append(self.open_verse)
 147
 148     def get_open_verse(self):
 149         if self.open_verse is None:
 150             self.open_normal_verse()
 151         return self.open_verse
 152
 153     def push_text(self, text):
 154         if not text:
 155             return
 156         for i, verse_text in enumerate(re.split(r"/\s*\n", text)):
 157             if i:
 158                 self.open_normal_verse()
 159             verse = self.get_open_verse()
 160             if len(verse):
 161                 verse[-1].tail = (verse[-1].tail or "") + verse_text
 162             else:
 163                 verse.text = (verse.text or "") + verse_text
 164
 165     def push_elem(self, elem):
 166         if elem.tag.startswith("wers"):
 167             verse = deepcopy(elem)
 168             verse.tail = None
 169             self.verses.append(verse)
 170             self.open_verse = verse
 171         else:
 172             appended = deepcopy(elem)
 173             appended.tail = None
 174             self.get_open_verse().append(appended)
 175
 176
 177 def replace_by_verse(tree):
 178     """ Find stanzas and create new verses in place of a '/' character """
 179
 180     stanzas = tree.findall('.//' + WLNS('strofa'))
 181     for stanza in stanzas:
 182         Stanza(stanza).versify()
 183
 184
 185 def add_to_manifest(manifest, partno):
 186     """ Adds a node to the manifest section in content.opf file """
 187
 188     partstr = 'part%d' % partno
 189     e = manifest.makeelement(OPFNS('item'), attrib={
 190                                  'id': partstr,
 191                                  'href': partstr + '.html',
 192                                  'media-type': 'application/xhtml+xml',
 193                              })
 194     manifest.append(e)
 195
 196
 197 def add_to_spine(spine, partno):
 198     """ Adds a node to the spine section in content.opf file """
 199
 200     e = spine.makeelement(OPFNS('itemref'), attrib={'idref': 'part%d' % partno});
 201     spine.append(e)
 202
 203
 204 class TOC(object):
 205     def __init__(self, name=None, part_href=None):
 206         self.children = []
 207         self.name = name
 208         self.part_href = part_href
 209         self.sub_number = None
 210
 211     def add(self, name, part_href, level=0, is_part=True, index=None):
 212         assert level == 0 or index is None
 213         if level > 0 and self.children:
 214             return self.children[-1].add(name, part_href, level-1, is_part)
 215         else:
 216             t = TOC(name)
 217             t.part_href = part_href
 218             if index is not None:
 219                 self.children.insert(index, t)
 220             else:
 221                 self.children.append(t)
 222             if not is_part:
 223                 t.sub_number = len(self.children) + 1
 224                 return t.sub_number
 225
 226     def append(self, toc):
 227         self.children.append(toc)
 228
 229     def extend(self, toc):
 230         self.children.extend(toc.children)
 231
 232     def depth(self):
 233         if self.children:
 234             return max((c.depth() for c in self.children)) + 1
 235         else:
 236             return 0
 237
 238     def href(self):
 239         src = self.part_href
 240         if self.sub_number is not None:
 241             src += '#sub%d' % self.sub_number
 242         return src
 243
 244     def write_to_xml(self, nav_map, counter=1):
 245         for child in self.children:
 246             nav_point = nav_map.makeelement(NCXNS('navPoint'))
 247             nav_point.set('id', 'NavPoint-%d' % counter)
 248             nav_point.set('playOrder', str(counter))
 249
 250             nav_label = nav_map.makeelement(NCXNS('navLabel'))
 251             text = nav_map.makeelement(NCXNS('text'))
 252             text.text = re.sub(r'\n', ' ', child.name)
 253             nav_label.append(text)
 254             nav_point.append(nav_label)
 255
 256             content = nav_map.makeelement(NCXNS('content'))
 257             content.set('src', child.href())
 258             nav_point.append(content)
 259             nav_map.append(nav_point)
 260             counter = child.write_to_xml(nav_point, counter + 1)
 261         return counter
 262
 263     def html_part(self, depth=0):
 264         texts = []
 265         for child in self.children:
 266             texts.append(
 267                 "<div style='margin-left:%dem;'><a href='%s'>%s</a></div>" %
 268                 (depth, child.href(), child.name))
 269             texts.append(child.html_part(depth+1))
 270         return "\n".join(texts)
 271
 272     def html(self):
 273         with open(get_resource('epub/toc.html')) as f:
 274             t = unicode(f.read(), 'utf-8')
 275         return t % self.html_part()
 276
 277
 278 def used_chars(element):
 279     """ Lists characters used in an ETree Element """
 280     chars = set((element.text or '') + (element.tail or ''))
 281     for child in element:
 282         chars = chars.union(used_chars(child))
 283     return chars
 284
 285
 286 def chop(main_text):
 287     """ divide main content of the XML file into chunks """
 288
 289     # prepare a container for each chunk
 290     part_xml = etree.Element('utwor')
 291     etree.SubElement(part_xml, 'master')
 292     main_xml_part = part_xml[0] # master
 293
 294     last_node_part = False
 295
 296     # the below loop are workaround for a problem with epubs in drama ebooks without acts
 297     is_scene = False
 298     is_act = False
 299     for one_part in main_text:
 300         name = one_part.tag
 301         if name == 'naglowek_scena':
 302             is_scene = True
 303         elif name == 'naglowek_akt':
 304             is_act = True
 305
 306     for one_part in main_text:
 307         name = one_part.tag
 308         if is_act is False and is_scene is True:
 309             if name == 'naglowek_czesc':
 310                 yield part_xml
 311                 last_node_part = True
 312                 main_xml_part[:] = [deepcopy(one_part)]
 313             elif not last_node_part and name in ("naglowek_scena"):
 314                 yield part_xml
 315                 main_xml_part[:] = [deepcopy(one_part)]
 316             else:
 317                 main_xml_part.append(deepcopy(one_part))
 318                 last_node_part = False
 319         else:
 320             if name == 'naglowek_czesc':
 321                 yield part_xml
 322                 last_node_part = True
 323                 main_xml_part[:] = [deepcopy(one_part)]
 324             elif not last_node_part and name in ("naglowek_rozdzial", "naglowek_akt", "srodtytul"):
 325                 yield part_xml
 326                 main_xml_part[:] = [deepcopy(one_part)]
 327             else:
 328                 main_xml_part.append(deepcopy(one_part))
 329                 last_node_part = False
 330     yield part_xml
 331
 332
 333 def transform_chunk(chunk_xml, chunk_no, annotations, empty=False, _empty_html_static=[]):
 334     """ transforms one chunk, returns a HTML string, a TOC object and a set of used characters """
 335
 336     toc = TOC()
 337     for element in chunk_xml[0]:
 338         if element.tag in ("naglowek_czesc"):
 339             toc.add(node_name(element), "part%d.html#book-text" % chunk_no)
 340         elif element.tag in ("naglowek_rozdzial", "naglowek_akt", "srodtytul"):
 341             toc.add(node_name(element), "part%d.html" % chunk_no)
 342         elif element.tag in ('naglowek_podrozdzial', 'naglowek_scena'):
 343             subnumber = toc.add(node_name(element), "part%d.html" % chunk_no, level=1, is_part=False)
 344             element.set('sub', str(subnumber))
 345     if empty:
 346         if not _empty_html_static:
 347             _empty_html_static.append(open(get_resource('epub/emptyChunk.html')).read())
 348         chars = set()
 349         output_html = _empty_html_static[0]
 350     else:
 351         find_annotations(annotations, chunk_xml, chunk_no)
 352         replace_by_verse(chunk_xml)
 353         html_tree = xslt(chunk_xml, get_resource('epub/xsltScheme.xsl'))
 354         chars = used_chars(html_tree.getroot())
 355         output_html = etree.tostring(html_tree, method="html", pretty_print=True)
 356     return output_html, toc, chars
 357
 358
 359 def transform(wldoc, verbose=False,
 360               style=None, html_toc=False,
 361               sample=None, cover=None, flags=None):
 362     """ produces a EPUB file
 363
 364     sample=n: generate sample e-book (with at least n paragraphs)
 365     cover: a cover.Cover factory or True for default
 366     flags: less-advertising, without-fonts, working-copy, with-full-fonts
 367     """
 368
 369     def transform_file(wldoc, chunk_counter=1, first=True, sample=None):
 370         """ processes one input file and proceeds to its children """
 371
 372         replace_characters(wldoc.edoc.getroot())
 373
 374         # every input file will have a TOC entry,
 375         # pointing to starting chunk
 376         toc = TOC(wldoc.book_info.title, "part%d.html" % chunk_counter)
 377         chars = set()
 378         if first:
 379             # write book title page
 380             html_tree = xslt(wldoc.edoc, get_resource('epub/xsltTitle.xsl'))
 381             chars = used_chars(html_tree.getroot())
 382             zip.writestr('OPS/title.html',
 383                  etree.tostring(html_tree, method="html", pretty_print=True))
 384             # add a title page TOC entry
 385             toc.add(u"Strona tytułowa", "title.html")
 386         elif wldoc.book_info.parts:
 387             # write title page for every parent
 388             if sample is not None and sample <= 0:
 389                 chars = set()
 390                 html_string = open(get_resource('epub/emptyChunk.html')).read()
 391             else:
 392                 html_tree = xslt(wldoc.edoc, get_resource('epub/xsltChunkTitle.xsl'))
 393                 chars = used_chars(html_tree.getroot())
 394                 html_string = etree.tostring(html_tree, method="html", pretty_print=True)
 395             zip.writestr('OPS/part%d.html' % chunk_counter, html_string)
 396             add_to_manifest(manifest, chunk_counter)
 397             add_to_spine(spine, chunk_counter)
 398             chunk_counter += 1
 399
 400         if len(wldoc.edoc.getroot()) > 1:
 401             # rdf before style master
 402             main_text = wldoc.edoc.getroot()[1]
 403         else:
 404             # rdf in style master
 405             main_text = wldoc.edoc.getroot()[0]
 406             if main_text.tag == RDFNS('RDF'):
 407                 main_text = None
 408
 409         if main_text is not None:
 410             for chunk_xml in chop(main_text):
 411                 empty = False
 412                 if sample is not None:
 413                     if sample <= 0:
 414                         empty = True
 415                     else:
 416                         sample -= len(chunk_xml.xpath('//strofa|//akap|//akap_cd|//akap_dialog'))
 417                 chunk_html, chunk_toc, chunk_chars = transform_chunk(chunk_xml, chunk_counter, annotations, empty)
 418
 419                 toc.extend(chunk_toc)
 420                 chars = chars.union(chunk_chars)
 421                 zip.writestr('OPS/part%d.html' % chunk_counter, chunk_html)
 422                 add_to_manifest(manifest, chunk_counter)
 423                 add_to_spine(spine, chunk_counter)
 424                 chunk_counter += 1
 425
 426         for child in wldoc.parts():
 427             child_toc, chunk_counter, chunk_chars, sample = transform_file(
 428                 child, chunk_counter, first=False, sample=sample)
 429             toc.append(child_toc)
 430             chars = chars.union(chunk_chars)
 431
 432         return toc, chunk_counter, chars, sample
 433
 434
 435     document = deepcopy(wldoc)
 436     del wldoc
 437
 438     if flags:
 439         for flag in flags:
 440             document.edoc.getroot().set(flag, 'yes')
 441
 442     # add editors info
 443     document.edoc.getroot().set('editors', u', '.join(sorted(
 444         editor.readable() for editor in document.editors())))
 445     if document.book_info.funders:
 446         document.edoc.getroot().set('funders', u', '.join(
 447             document.book_info.funders))
 448     if document.book_info.thanks:
 449         document.edoc.getroot().set('thanks', document.book_info.thanks)
 450
 451     opf = xslt(document.book_info.to_etree(), get_resource('epub/xsltContent.xsl'))
 452     manifest = opf.find('.//' + OPFNS('manifest'))
 453     guide = opf.find('.//' + OPFNS('guide'))
 454     spine = opf.find('.//' + OPFNS('spine'))
 455
 456     output_file = NamedTemporaryFile(prefix='librarian', suffix='.epub', delete=False)
 457     zip = zipfile.ZipFile(output_file, 'w', zipfile.ZIP_DEFLATED)
 458
 459     # write static elements
 460     mime = zipfile.ZipInfo()
 461     mime.filename = 'mimetype'
 462     mime.compress_type = zipfile.ZIP_STORED
 463     mime.extra = ''
 464     zip.writestr(mime, 'application/epub+zip')
 465     zip.writestr('META-INF/container.xml', '<?xml version="1.0" ?><container version="1.0" ' \
 466                        'xmlns="urn:oasis:names:tc:opendocument:xmlns:container">' \
 467                        '<rootfiles><rootfile full-path="OPS/content.opf" ' \
 468                        'media-type="application/oebps-package+xml" />' \
 469                        '</rootfiles></container>')
 470     zip.write(get_resource('res/wl-logo-small.png'), os.path.join('OPS', 'logo_wolnelektury.png'))
 471     zip.write(get_resource('res/jedenprocent.png'), os.path.join('OPS', 'jedenprocent.png'))
 472     if not style:
 473         style = get_resource('epub/style.css')
 474     zip.write(style, os.path.join('OPS', 'style.css'))
 475
 476     if cover:
 477         if cover is True:
 478             cover = DefaultEbookCover
 479
 480         cover_file = StringIO()
 481         bound_cover = cover(document.book_info)
 482         bound_cover.save(cover_file)
 483         cover_name = 'cover.%s' % bound_cover.ext()
 484         zip.writestr(os.path.join('OPS', cover_name), cover_file.getvalue())
 485         del cover_file
 486
 487         cover_tree = etree.parse(get_resource('epub/cover.html'))
 488         cover_tree.find('//' + XHTMLNS('img')).set('src', cover_name)
 489         zip.writestr('OPS/cover.html', etree.tostring(
 490                         cover_tree, method="html", pretty_print=True))
 491
 492         if bound_cover.uses_dc_cover:
 493             if document.book_info.cover_by:
 494                 document.edoc.getroot().set('data-cover-by', document.book_info.cover_by)
 495             if document.book_info.cover_source:
 496                 document.edoc.getroot().set('data-cover-source', document.book_info.cover_source)
 497
 498         manifest.append(etree.fromstring(
 499             '<item id="cover" href="cover.html" media-type="application/xhtml+xml" />'))
 500         manifest.append(etree.fromstring(
 501             '<item id="cover-image" href="%s" media-type="%s" />' % (cover_name, bound_cover.mime_type())))
 502         spine.insert(0, etree.fromstring('<itemref idref="cover"/>'))
 503         opf.getroot()[0].append(etree.fromstring('<meta name="cover" content="cover-image"/>'))
 504         guide.append(etree.fromstring('<reference href="cover.html" type="cover" title="Okładka"/>'))
 505
 506
 507     annotations = etree.Element('annotations')
 508
 509     toc_file = etree.fromstring('<?xml version="1.0" encoding="utf-8"?><!DOCTYPE ncx PUBLIC ' \
 510                                '"-//NISO//DTD ncx 2005-1//EN" "http://www.daisy.org/z3986/2005/ncx-2005-1.dtd">' \
 511                                '<ncx xmlns="http://www.daisy.org/z3986/2005/ncx/" xml:lang="pl" ' \
 512                                'version="2005-1"><head></head><docTitle></docTitle><navMap>' \
 513                                '</navMap></ncx>')
 514     nav_map = toc_file[-1]
 515
 516     if html_toc:
 517         manifest.append(etree.fromstring(
 518             '<item id="html_toc" href="toc.html" media-type="application/xhtml+xml" />'))
 519         spine.append(etree.fromstring(
 520             '<itemref idref="html_toc" />'))
 521         guide.append(etree.fromstring('<reference href="toc.html" type="toc" title="Spis treści"/>'))
 522
 523     toc, chunk_counter, chars, sample = transform_file(document, sample=sample)
 524
 525     if len(toc.children) < 2:
 526         toc.add(u"Początek utworu", "part1.html")
 527
 528     # Last modifications in container files and EPUB creation
 529     if len(annotations) > 0:
 530         toc.add("Przypisy", "annotations.html")
 531         manifest.append(etree.fromstring(
 532             '<item id="annotations" href="annotations.html" media-type="application/xhtml+xml" />'))
 533         spine.append(etree.fromstring(
 534             '<itemref idref="annotations" />'))
 535         replace_by_verse(annotations)
 536         html_tree = xslt(annotations, get_resource('epub/xsltAnnotations.xsl'))
 537         chars = chars.union(used_chars(html_tree.getroot()))
 538         zip.writestr('OPS/annotations.html', etree.tostring(
 539                             html_tree, method="html", pretty_print=True))
 540
 541     toc.add("Wesprzyj Wolne Lektury", "support.html")
 542     manifest.append(etree.fromstring(
 543         '<item id="support" href="support.html" media-type="application/xhtml+xml" />'))
 544     spine.append(etree.fromstring(
 545         '<itemref idref="support" />'))
 546     html_string = open(get_resource('epub/support.html')).read()
 547     chars.update(used_chars(etree.fromstring(html_string)))
 548     zip.writestr('OPS/support.html', html_string)
 549
 550     toc.add("Strona redakcyjna", "last.html")
 551     manifest.append(etree.fromstring(
 552         '<item id="last" href="last.html" media-type="application/xhtml+xml" />'))
 553     spine.append(etree.fromstring(
 554         '<itemref idref="last" />'))
 555     html_tree = xslt(document.edoc, get_resource('epub/xsltLast.xsl'))
 556     chars.update(used_chars(html_tree.getroot()))
 557     zip.writestr('OPS/last.html', etree.tostring(
 558                         html_tree, method="html", pretty_print=True))
 559
 560     if not flags or not 'without-fonts' in flags:
 561         # strip fonts
 562         tmpdir = mkdtemp('-librarian-epub')
 563         try:
 564             cwd = os.getcwd()
 565         except OSError:
 566             cwd = None
 567
 568         os.chdir(os.path.join(os.path.dirname(os.path.realpath(__file__)), 'font-optimizer'))
 569         for fname in 'DejaVuSerif.ttf', 'DejaVuSerif-Bold.ttf', 'DejaVuSerif-Italic.ttf', 'DejaVuSerif-BoldItalic.ttf':
 570             if not flags or not 'with-full-fonts' in flags:
 571                 optimizer_call = ['perl', 'subset.pl', '--chars', ''.join(chars).encode('utf-8'),
 572                               get_resource('fonts/' + fname), os.path.join(tmpdir, fname)]
 573                 if verbose:
 574                     print "Running font-optimizer"
 575                     subprocess.check_call(optimizer_call)
 576                 else:
 577                     subprocess.check_call(optimizer_call, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 578                     zip.write(os.path.join(tmpdir, fname), os.path.join('OPS', fname))
 579             else:
 580                 zip.write(get_resource('fonts/' + fname), os.path.join('OPS', fname))
 581             manifest.append(etree.fromstring(
 582                 '<item id="%s" href="%s" media-type="application/x-font-truetype" />' % (fname, fname)))
 583         rmtree(tmpdir)
 584         if cwd is not None:
 585             os.chdir(cwd)
 586     zip.writestr('OPS/content.opf', etree.tostring(opf, pretty_print=True, xml_declaration = True, encoding='UTF-8'))
 587     title = document.book_info.title
 588     attributes = "dtb:uid", "dtb:depth", "dtb:totalPageCount", "dtb:maxPageNumber"
 589     for st in attributes:
 590         meta = toc_file.makeelement(NCXNS('meta'))
 591         meta.set('name', st)
 592         meta.set('content', '0')
 593         toc_file[0].append(meta)
 594     toc_file[0][0].set('content', str(document.book_info.url))
 595     toc_file[0][1].set('content', str(toc.depth()))
 596     set_inner_xml(toc_file[1], ''.join(('<text>', title, '</text>')))
 597
 598     # write TOC
 599     if html_toc:
 600         toc.add(u"Spis treści", "toc.html", index=1)
 601         zip.writestr('OPS/toc.html', toc.html().encode('utf-8'))
 602     toc.write_to_xml(nav_map)
 603     zip.writestr('OPS/toc.ncx', etree.tostring(toc_file, pretty_print=True, xml_declaration = True, encoding='UTF-8'))
 604     zip.close()
 605
 606     return OutputFile.from_filename(output_file.name)