1 files changed, 48 insertions, 0 deletions
diff --git a/plugins/footnote-postprocess.lua b/plugins/footnote-postprocess.lua
new file mode 100644
index 0000000..5daaa65
--- /dev/null
+++ b/plugins/footnote-postprocess.lua
@@ -0,0 +1,48 @@
+-- Turn `markdown-it-footnote` output into Tufte-compatible sidenotes.
+
+footnotes = HTML.select(page, ".footnote-ref")
+
+index, footnote = next(footnotes)
+
+while index do
+  ahref = HTML.select_one(footnote, "a")
+  href = HTML.get_attribute(ahref, "href")
+  href = Regex.replace(href, "^\#", "")
+  footnote_contents = HTML.select_one(page, "li#" .. href)
+  HTML.delete(HTML.select_one(footnote_contents, ".footnote-backref"))
+
+  paragraphs = HTML.select(footnote_contents, "p")
+  i, p = next(paragraphs)
+
+  while i do
+    HTML.set_tag_name(p, "span")
+    HTML.add_class(p, "footnote-p")
+    i, p = next(paragraphs, i)
+  end
+
+  footnote_contents = HTML.inner_html(footnote_contents)
+
+  label = HTML.create_element("label")
+  HTML.add_class(label, "margin-toggle")
+  HTML.add_class(label, "sidenote-number")
+  HTML.set_attribute(label, "for", href)
+  HTML.insert_after(footnote, label)
+
+  input = HTML.create_element("input")
+  HTML.add_class(input, "margin-toggle")
+  HTML.set_attribute(input, "type", "checkbox")
+  HTML.set_attribute(input, "id", href)
+  HTML.insert_after(label, input)
+
+  contents_node = HTML.create_element("span")
+  HTML.add_class(contents_node, "note")
+  HTML.add_class(contents_node, "sidenote")
+  HTML.append_child(contents_node, HTML.parse(footnote_contents))
+  HTML.insert_after(input, contents_node)
+
+  HTML.delete(footnote)
+  index, footnote = next(footnotes, index)
+end
+
+HTML.delete(HTML.select_one(page, "hr.footnotes-sep"))
+HTML.delete(HTML.select_one(page, "section.footnotes"))