local p = {}

local units = {
	year = "^%d*$",
	year_bc = "^%d* BC$",
	year_ad = "^AD %d*$",
	decade = "^%d*0s$",
	decade_bc = "^%d*0s BC$",
	century = "^%d*[snrt][tdh].century$",
	century_bc = "^%d*[snrt][tdh].century BC$",
	millennium = "^%d*[snrt][tdh].millennium$",
	millennium_bc = "^%d*[snrt][tdh].millennium BC$",
}

function p.main(frame)
	local title = mw.title.getCurrentTitle().text

	for unit, pattern in pairs(units) do
		if string.match(title, pattern) then
			return unit
		end
	end

	return -1
end

return p