Add "SEE ALSO" section to manual pages where applicable

1 files changed, 73 insertions, 0 deletions

diff --git a/assets/manual/filter_man.lua b/assets/manual/filter_man.lua
new file mode 100644
index 0000000..0178462
--- /dev/null
+++ b/assets/manual/filter_man.lua
@@ -0,0 +1,73 @@
+local filters = {}
+
+local function add_filter(x)
+	table.insert(filters, x)
+end
+
+local is_latex = FORMAT:match "latex"
+local is_man = FORMAT:match "man"
+
+add_filter {
+	Pandoc = function(elem)
+		local seealso = elem.meta.seealso
+		if not seealso then
+			return
+		end
+		local blocks = elem.blocks
+		blocks:insert(pandoc.Header(1, pandoc.Str("SEE ALSO")))
+		if is_man then
+			for k, v in pairs(seealso) do
+				seealso[k] = v[1].text
+			end
+			blocks:insert(pandoc.Str(table.concat(seealso, ", ")))
+		else
+			local list = {}
+			for _, i in ipairs(seealso) do
+				local page = i[1].text
+				local pgname, pgsection = string.match(page, "^([^%)]+)%(([^%)]+)%)$")
+				local item = pandoc.Str(page)
+				if is_latex and pgname and pgsection then
+					pgname = pgname:gsub("_","\\string_")
+					item = pandoc.RawInline("latex", string.format("\\manref{%s}{%s}", pgname, pgsection))
+				end
+				table.insert(list, item)
+			end
+			blocks:insert(pandoc.BulletList(list))
+		end
+		return elem
+	end
+}
+
+if is_latex then
+	add_filter {
+		Str = function(elem)
+			if elem.tex == "Advtrains" then
+				return pandoc.RawInline("latex", "\\advtrains{}")
+			end
+		end
+	}
+	add_filter {
+		Header = function(elem)
+			local attr = {
+				class = "unnumbered unlisted",
+			}
+			return pandoc.Header(elem.level+1, elem.content, attr)
+		end,
+	}
+	add_filter {
+		Pandoc = function(elem)
+			local outputfn = PANDOC_STATE.output_file or error("No output file specified")
+			local pgname, pgsection = outputfn:match("([^%./\\]+)%.([^%.]+)%.tex$")
+			assert(pgname and pgsection, "Cannot fetch manpage name and section")
+			local blocks = elem.blocks
+			local titlestr = string.format("%s(%s)", pgname, pgsection)
+			local titleid = string.format("man:%s.%s", pgname, pgsection)
+			local titleobj = pandoc.Header(1, pandoc.Code(titlestr))
+			titleobj.identifier = titleid
+			blocks:insert(1, titleobj)
+			return elem
+		end,
+	}
+end
+
+return filters