#!/usr/libexec/flua

-- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
--
-- Copyright(c) 2022 Baptiste Daroussin <[email protected]>

local nuage = require("nuage")
local yaml = require("yaml")

if #arg ~= 2 then
	nuage.err("Usage ".. arg[0] .." <cloud-init directory> [config-2|nocloud]")
end
local path = arg[1]
local citype = arg[2]
local ucl = require("ucl")

local default_user = {
	name = "freebsd",
	homedir = "/home/freebsd",
	groups = "wheel",
	gecos = "FreeBSD User",
	shell = "/bin/sh",
	plain_text_passwd = "freebsd"
}

local root = os.getenv("NUAGE_FAKE_ROOTDIR")
if not root then
	root = ""
end

local function open_config(name)
	nuage.mkdir_p(root .. "/etc/rc.conf.d")
	local f,err = io.open(root .. "/etc/rc.conf.d/" .. name, "w")
	if not f then
		nuage.err("nuageinit: unable to open "..name.." config: " .. err)
	end
	return f
end

local function get_ifaces()
	local parser = ucl.parser()
	-- grab ifaces
	local ns  = io.popen('netstat -i --libxo json')
	local netres = ns:read("*a")
	ns:close()
	local res,err = parser:parse_string(netres)
	if not res then
		nuage.warn("Error parsing netstat -i --libxo json outout: " .. err)
		return nil
	end
	local ifaces = parser:get_object()
	local myifaces = {}
	for _,iface in pairs(ifaces["statistics"]["interface"]) do
		if iface["network"]:match("<Link#%d>") then
			local s = iface["address"]
			myifaces[s:lower()] = iface["name"]
		end
	end
	return myifaces
end

local function config2_network(p)
	local parser = ucl.parser()
	local f = io.open(p .. "/network_data.json")
	if not f then
		-- silently return no network configuration is provided
		return
	end
	f:close()
	local res,err = parser:parse_file(p .. "/network_data.json")
	if not res then
		nuage.warn("nuageinit: error parsing network_data.json: " .. err)
		return
	end
	local obj = parser:get_object()

	local ifaces = get_ifaces()
	if not ifaces then
		nuage.warn("nuageinit: no network interfaces found")
		return
	end
	local mylinks = {}
	for _,v in pairs(obj["links"]) do
		local s = v["ethernet_mac_address"]:lower()
		mylinks[v["id"]] = ifaces[s]
	end

	nuage.mkdir_p(root .. "/etc/rc.conf.d")
	local network = open_config("network")
	local routing = open_config("routing")
	local ipv6 = {}
	local ipv6_routes = {}
	local ipv4 = {}
	for _,v in pairs(obj["networks"]) do
		local interface = mylinks[v["link"]]
		if v["type"] == "ipv4_dhcp" then
			network:write("ifconfig_"..interface.."=\"DHCP\"\n")
		end
		if v["type"] == "ipv4" then
			network:write("ifconfig_"..interface.."=\"inet "..v["ip_address"].." netmask " .. v["netmask"] .. "\"\n")
			if v["gateway"] then
				routing:write("defaultrouter=\""..v["gateway"].."\"\n")
			end
			if v["routes"] then
				for i,r in ipairs(v["routes"]) do
					local rname = "cloudinit" .. i .. "_" .. interface
					if v["gateway"] and v["gateway"] == r["gateway"] then goto next end
					if r["network"] == "0.0.0.0" then
						routing:write("defaultrouter=\""..r["gateway"].."\"\n")
						goto next
					end
					routing:write("route_".. rname .. "=\"-net ".. r["network"] .. " ")
					routing:write(r["gateway"] .. " " .. r["netmask"] .. "\"\n")
					ipv4[#ipv4 + 1] = rname
					::next::
				end
			end
		end
		if v["type"] == "ipv6" then
			ipv6[#ipv6+1] = interface
			ipv6_routes[#ipv6_routes+1] = interface
			network:write("ifconfig_"..interface.."_ipv6=\"inet6 "..v["ip_address"].."\"\n")
			if v["gateway"] then
				routing:write("ipv6_defaultrouter=\""..v["gateway"].."\"\n")
				routing:write("ipv6_route_"..interface.."=\""..v["gateway"])
				routing:write(" -prefixlen 128 -interface "..interface.."\"\n")
			end
			-- TODO compute the prefixlen for the routes
			--if v["routes"] then
			--	for i,r in ipairs(v["routes"]) do
			--	local rname = "cloudinit" .. i .. "_" .. mylinks[v["link"]]
			--		-- skip all the routes which are already covered by the default gateway, some provider
			--		-- still list plenty of them.
			--		if v["gateway"] == r["gateway"] then goto next end
			--		routing:write("ipv6_route_" .. rname .. "\"\n")
			--		ipv6_routes[#ipv6_routes+1] = rname
			--		::next::
			--	end
			--end
		end
	end
	if #ipv4 > 0 then
		routing:write("static_routes=\"")
		routing:write(table.concat(ipv4, " ") .. "\"\n")
	end
	if #ipv6 > 0 then
		network:write("ipv6_network_interfaces=\"")
		network:write(table.concat(ipv6, " ") .. "\"\n")
		network:write("ipv6_default_interface=\""..ipv6[1].."\"\n")
	end
	if #ipv6_routes > 0 then
		routing:write("ipv6_static_routes=\"")
		routing:write(table.concat(ipv6, " ") .. "\"\n")
	end
	network:close()
	routing:close()
end

if citype == "config-2" then
	local parser = ucl.parser()
	local res,err = parser:parse_file(path..'/meta_data.json')

	if not res then
		nuage.err("nuageinit: error parsing config-2: meta_data.json: " .. err)
	end
	local obj = parser:get_object()
	nuage.sethostname(obj["hostname"])

	-- network
	config2_network(path)
elseif citype == "nocloud" then
	local f,err = io.open(path.."/meta-data")
	if err then
		nuage.err("nuageinit: error parsing nocloud meta-data: ".. err)
	end
	local obj = yaml.eval(f:read("*a"))
	f:close()
	if not obj then
		nuage.err("nuageinit: error parsing nocloud meta-data")
	end
	local hostname = obj['local-hostname']
	if not hostname then
		hostname = obj['hostname']
	end
	if hostname then
		nuage.sethostname(hostname)
	end
else
	nuage.err("Unknown cloud init type: ".. citype)
end

-- deal with user-data
local f = io.open(path..'/user-data', "r")
if not f then
	os.exit(0)
end
local line = f:read('*l')
f:close()
if line == "#cloud-config" then
	f = io.open(path.."/user-data")
	local obj = yaml.eval(f:read("*a"))
	f:close()
	if not obj then
		nuage.err("nuageinit: error parsing cloud-config file: user-data")
	end
	if obj.groups then
		for n,g in pairs(obj.groups) do
			if (type(g) == "string") then
				local r = nuage.addgroup({name = g})
				if not r then
					nuage.warn("nuageinit: failed to add group: ".. g)
				end
			elseif type(g) == "table" then
				for k,v in pairs(g) do
					nuage.addgroup({name = k, members = v})
				end
			else
				nuage.warn("nuageinit: invalid type : "..type(g).." for users entry number "..n);
			end
		end
	end
	if obj.users then
		for n,u in pairs(obj.users) do
			if type(u) == "string" then
				if u == "default" then
					nuage.adduser(default_user)
				else
					nuage.adduser({name = u})
				end
			elseif type(u) == "table" then
				-- ignore users without a username
				if u.name == nil then
					goto unext
				end
				local homedir = nuage.adduser(u)
				if u.ssh_authorized_keys then
					for _,v in ipairs(u.ssh_authorized_keys) do
						nuage.addsshkey(homedir, v)
					end
				end
			else
				nuage.warn("nuageinit: invalid type : "..type(u).." for users entry number "..n);
			end
			::unext::
		end
	else
	-- default user if none are defined
		nuage.adduser(default_user)
	end
	if obj.ssh_authorized_keys then
		local homedir = nuage.adduser(default_user)
		for _,k in ipairs(obj.ssh_authorized_keys) do
			nuage.addsshkey(homedir, k)
		end
	end
	if obj.network then
		local ifaces = get_ifaces()
		nuage.mkdir_p(root .. "/etc/rc.conf.d")
		local network = open_config("network")
		local routing = open_config("routing")
		local ipv6={}
		for _,v in pairs(obj.network.ethernets) do
			if not v.match then goto next end
			if not v.match.macaddress then goto next end
			if not ifaces[v.match.macaddress] then
				nuage.warn("nuageinit: not interface matching: "..v.match.macaddress)
				goto next
			end
			local interface = ifaces[v.match.macaddress]
			if v.dhcp4 then
				network:write("ifconfig_"..interface.."=\"DHCP\"\n")
			elseif v.addresses then
				for _,a in pairs(v.addresses) do
					if a:match("^(%d+)%.(%d+)%.(%d+)%.(%d+)") then
						network:write("ifconfig_"..interface.."=\"inet "..a.."\"\n")
					else
						network:write("ifconfig_"..interface.."_ipv6=\"inet6 "..a.."\"\n")
						ipv6[#ipv6 +1] = interface
					end
				end
			end
			if v.gateway4 then
				routing:write("defaultrouter=\""..v.gateway4.."\"\n")
			end
			if v.gateway6 then
				routing:write("ipv6_defaultrouter=\""..v.gateway6.."\"\n")
				routing:write("ipv6_route_"..interface.."=\""..v.gateway6)
				routing:write(" -prefixlen 128 -interface "..interface.."\"\n")
			end
			::next::
		end
		if #ipv6 > 0 then
			network:write("ipv6_network_interfaces=\"")
			network:write(table.concat(ipv6, " ") .. "\"\n")
			network:write("ipv6_default_interface=\""..ipv6[1].."\"\n")
		end
		network:close()
		routing:close()
	end
else
	local res,err = os.execute(path..'/user-data')
	if not res then
		nuage.err("nuageinit: error executing user-data script: ".. err)
	end
end