{% assign documents = site.documents | where: "collection", site.theme-settings.collection | where_exp: "page", "page.chapnum != null" %} {% if page.subsite %} {% assign documents = documents | where: "subsite", page.subsite %} {% endif %} {% assign pages = documents | where_exp: "page", "page.pagenum != null" | sort: "pagenum" %} {% assign indices = documents | where_exp: "page", "page.pagenum == null" | sort: "chapnum" %} {% assign sorted = "" | split: "" %} {% for index in indices %} {% assign chapter_pages = pages | where: "chapnum", index.chapnum %} {% assign sorted = sorted | concat: chapter_pages %} {% endfor %} {% assign previous = nil %} {% for p in sorted %} {% if p.chapnum < page.chapnum or (p.chapnum == page.chapnum and p.pagenum < page.pagenum) %} {% assign previous = p %} {% endif %} {% endfor %} {% assign sorted = sorted | reverse %} {% assign next = nil %} {% for p in sorted %} {% if p.chapnum > page.chapnum or (p.chapnum == page.chapnum and p.pagenum > page.pagenum) %} {% assign next = p %} {% endif %} {% endfor %}
{% if previous != nil %} {% endif %} {% if next != nil %} {% endif %}