init.lua

--[[
 Whiter List mod by Jordan Irwin (AntumDeluge)
 License: MIT

 Original Whitelist mod by ShadowNinja
 License: WTFPL
--]]

local world_path = core.get_worldpath()
local admin = core.settings:get("name")
local whitelist = {}

local S = core.get_translator(core.get_current_modname())

-- Enabled by default
local enabled = core.settings:get_bool("whitelist.enable", true)
local deny_message = core.settings:get("whitelist.message") or "Server access is restricted to whitelisted players only."
deny_message = S(deny_message)


--- Loads whitelisted names into memory.
local function load_whitelist()
	local file, err = io.open(world_path .. "/whitelist.txt", "r")
	if err then return end

	-- FIXME: error if "whitelist.txt" is a directory

	-- reset for session in case names have been manually removed
	whitelist = {}

	for line in file:lines() do
		-- ignore lines with whitespace only
		if line:gsub("%s+", "") ~= "" then
			whitelist[line] = true
		end
	end

	file:close()
end


--- Writes whitelisted names to file.
local function save_whitelist()
	local file, err = io.open(world_path .. "/whitelist.txt", "w")
	if err then
		core.log("error", S("Could not open whitelist file for writing: @1", err))
		return
	end

	for item in pairs(whitelist) do
		file:write(item .. "\n")
	end

	file:close()
end


if enabled then
	core.register_on_prejoinplayer(function(name, ip)
		load_whitelist()
		if core.is_singleplayer() or name == admin or whitelist[name] then
			return
		end

		return deny_message
	end)
end

core.register_chatcommand("whitelist", {
	params = "[{add|remove} <" .. S("name") .. ">]",
	description = S("Manage the whitelist."),
	privs = {ban=true},
	func = function(name, param)
		local action, whitename
		if param:find(" ") then
			action, whitename = param:match("^([^ ]+) ([^ ]+)$")
		else
			action = param
		end

		-- update whitelist from file before performing actions
		load_whitelist()

		if action == "" then
			local names = {}
			for k, v in pairs(whitelist) do
				table.insert(names, k)
			end

			return true, S("Whitelisted names: @1", table.concat(names, ", "))
		end

		if not whitename then
			return false, S("Must supply name parameter.")
		end

		if action == "query" then
			local msg
			if whitelist[whitename] then
				msg = S("@1 is already on the whitelist.", whitename)
			else
				msg = S("@1 is not on the whitelist.", whitename)
			end

			return true, msg
		elseif action == "add" then
			if whitelist[whitename] then
				return false, S("@1 is already on the whitelist.", whitename)
			end

			whitelist[whitename] = true
			save_whitelist()
			return true, S("Added @1 to the whitelist.", whitename)
		elseif action == "remove" then
			if not whitelist[whitename] then
				return false, S("@1 is not on the whitelist.", whitename)
			end

			whitelist[whitename] = nil
			save_whitelist()
			return true, S("Removed @1 from the whitelist.", whitename)
		end

		return false, S("Invalid action: @1", action)
	end,
})