+def add_table_of_contents(root):
+ sections = []
+ counter = 1
+ for element in root.iterdescendants():
+ if element.tag in ('h2', 'h3'):
+ if any_ancestor(element, lambda e: e.get('id') in ('footnotes',)):
+ continue
+
+ if element.tag == 'h3' and len(sections) and sections[-1][1] == 'h2':
+ sections[-1][3].append((counter, element.tag, ''.join(element.xpath('text()')), []))
+ else:
+ sections.append((counter, element.tag, ''.join(element.xpath('text()')), []))
+ add_anchor(element, "s%d" % counter, with_link=False)
+ counter += 1
+
+ toc = etree.Element('div')
+ toc.set('id', 'toc')
+ toc_header = etree.SubElement(toc, 'h2')
+ toc_header.text = u'Spis treści'
+ toc_list = etree.SubElement(toc, 'ol')
+
+ for n, section, text, subsections in sections:
+ section_element = etree.SubElement(toc_list, 'li')
+ add_anchor(section_element, "s%d" % n, with_target=False, link_text=text)
+
+ if len(subsections):
+ subsection_list = etree.SubElement(section_element, 'ol')
+ for n, subsection, text, _ in subsections:
+ subsection_element = etree.SubElement(subsection_list, 'li')
+ add_anchor(subsection_element, "s%d" % n, with_target=False, link_text=text)
+
+ root.insert(0, toc)
+