Jekyll automatic page navigation

navigation.liquid

{% comment %}
	This snippet spits out the HTML navigation derived from the front matter settings in your markdown files.
	https://gist.github.com/dominikwilkowski/c7d916c9b36e4eebbc90

	Usage:
		{% include navigation.liquid %}

	Return:
		HTML direct output

	Required:
		Front matter needs this element:
			---
			weight: "010.030.020"
			---
{% endcomment %}


{% assign pages = site.pages | sort: "weight" %}
{% assign levels = 0 %}

<nav class="navigation-wrapper">
	<ul class="navigation">
		{% for thisPage in pages %}


			{% comment %}
				GETTING CURRENT LEVEL
			{% endcomment %}
			{% assign thisLevels = thisPage.weight | split: "." %}
			{% assign thisLevels = thisLevels.size %}


			{% comment %}
				SAME LEVEL
			{% endcomment %}
			{% if level == thisLevels %}
				</li>
			{% endif %}


			{% comment %}
				NEXT HIGHER LEVEL
			{% endcomment %}
			{% if level < thisLevels %}
				<ul class="navigation-subnav">
			{% endif %}


			{% comment %}
				NEXT LOWER LEVEL
			{% endcomment %}
			{% if level > thisLevels %}
					</li>
				</ul>
			{% endif %}

			{% comment %}
				OUTPUT THE LINK
			{% endcomment %}
			<li class="navigation-item">
				<a class="navigation-link{% if page.url == thisPage.url %} is-active{% endif %}" href="{{ thisPage.url }}">
					{{ thisPage.title }}
				</a>


			{% comment %}
				ASSIGNING CURRENT LEVEL
			{% endcomment %}
			{% assign level = thisLevels %}

		{% endfor %}

		</li>
	</ul>
</nav>

page1.md

layout	weight
default	010

Page 1

page2.md

layout	weight
default	020

Page 2

page3.md

layout	weight
default	030

Page 3

subpage1.md

layout	weight
default	020.10

Subpage 1