-- Generate util/dnsregistry.lua from IANA HTTP status code registry

local xml = require "util.xml";

local registries = xml.parse(io.read("*a"), { allow_processing_instructions = true });

print("-- Source: https://www.iana.org/assignments/dns-parameters/dns-parameters.xml");

print(os.date("-- Generated on %Y-%m-%d"))

local registry_mapping = {

	["dns-parameters-2"] = "classes";

	["dns-parameters-4"] = "types";

	["dns-parameters-6"] = "errors";

};

print("return {");

for registry in registries:childtags("registry") do

	local registry_name = registry_mapping[registry.attr.id];

	if registry_name then

		print("\t" .. registry_name .. " = {");

		for record in registry:childtags("record") do

			local record_name = record:get_child_text("name");

			local record_type = record:get_child_text("type");

			local record_desc = record:get_child_text("description");

			local record_code = tonumber(record:get_child_text("value"));

			if tostring(record):lower():match("reserved") or tostring(record):lower():match("reserved") then

				record_code = nil;

			end

			if registry_name == "classes" and record_code then

				record_type = record_desc and record_desc:match("%((%w+)%)$")

				if record_type then

					print(("\t\t[%q] = %d; [%d] = %q;"):format(record_type, record_code, record_code, record_type))

				end

			elseif registry_name == "types" and record_type and record_code then

				print(("\t\t[%q] = %d; [%d] = %q;"):format(record_type, record_code, record_code, record_type))

			elseif registry_name == "errors" and record_code and record_name then

				print(("\t\t[%d] = %q; [%q] = %q;"):format(record_code, record_name, record_name, record_desc or record_name));

			end

		end

		print("\t};");

	end

end

print("};");