{# Recursively render a page's headings table of contents #}
{%- macro render_book_page_toc(children, indents) -%}
	{%- set tabs = "" -%}
	{%- for i in range(end = indents) -%}
		{%- set_global tabs = tabs ~ "	" -%}
	{%- endfor -%}

	{%- if children | length > 0 %}
	{{ tabs }}<ul>
	{%- for child in children %}
	{{ tabs }}	<li><a href="#{{ child.id }}" title="{{ child.title | safe }}">{{ child.title }}</a></li>
	{{- self::render_book_page_toc(children = child.children, indents = indents + 1) -}}
	{%- endfor %}
	{{ tabs }}</ul>
	{%- endif -%}
{%- endmacro render_book_page_toc -%}

{# Recursively render a book's chapters table of contents #}
{%- macro render_book_outline(parent, current_path, index, indents) -%}
	{#- Setup -#}
	{%- set chapters = parent.pages | default(value = []) -%}
	{%- if index == 0 -%}
		{%- set_global chapters = [parent] -%}
	{%- else -%}
	{%- for subsection_path in parent.subsections -%}
		{%- set_global chapters = chapters | concat(with = get_section(path = subsection_path)) -%}
	{%- endfor -%}
	{%- endif -%}
	{%- if index > 0 -%}
	{%- set_global chapters = chapters | sort(attribute = "extra.order") -%}
	{%- endif -%}
	{#- End of setup -#}

	{%- set tabs = "" -%}
	{%- for i in range(end = indents) -%}
		{%- set_global tabs = tabs ~ "	" -%}
	{%- endfor -%}

	{%- if chapters | length > 0 %}
	{{ tabs }}<ul>
		{%- for chapter in chapters %}
		{%- set children = chapter.pages or chapter.subsections | default(value = []) -%}
		{%- set_global classes = [] -%}
		{%- if index == 0 -%}
			{%- set_global classes = classes | concat(with = "title") -%}
		{%- endif -%}
		{%- if index == 1 -%}
			{%- set_global classes = classes | concat(with = "chapter") -%}
		{%- endif -%}
		{%- if current_path == chapter.path -%}
			{%- set_global classes = classes | concat(with = "active") -%}
		{%- endif %}
		{{ tabs }}<li {%- if classes | length > 0 %} class="{{ classes | join(sep = " ") }}"{% endif %}>
			{{ tabs }}<label>{% if children and not index == 0 %}<input type="checkbox" {%- if current_path is starting_with(chapter.path) %} checked{% endif %} />{% endif %}</label>
			{{ tabs }}<a href="{{ chapter.path | safe }}" title="{{ chapter.title | safe }}">{{ chapter.title }}</a>
		{{ tabs }}</li>
		{%- if children -%}
		{{ self::render_book_outline(parent = chapter, current_path = current_path, index = index + 1, indents = indents + 1) }}
		{%- endif %}
		{%- endfor %}
	{{ tabs }}</ul>
	{%- endif -%}
{%- endmacro render_book_outline -%}

{# Recursively flatten the book outline to a string for sequential navigation #}
{%- macro flatten_book_outline(section) -%}
	{#- Setup -#}
	{%- set items = [] -%}
	{%- if section.pages -%}
		{%- set_global items = items | concat(with = section.pages) -%}
	{%- endif -%}
	{%- if section.subsections -%}
		{%- for subsection_path in section.subsections -%}
			{%- set subsection = get_section(path = subsection_path) -%}
			{%- set_global items = items | concat(with = subsection) -%}
		{%- endfor -%}
	{%- endif -%}
	{%- set items = items | sort(attribute = "extra.order") -%}
	{#- End of setup -#}

	{%- for item in items -%}
		{{ item.path }},,,,,{{ item.title }};;;;;
		{%- if item.pages or item.subsections -%}
			{{ self::flatten_book_outline(section = item) }}
		{%- endif -%}
	{%- endfor -%}
{%- endmacro flatten_book_outline -%}