init empty files if there's no one present

* provide a way to initialize files if there is not one
  currently doe snot touch the auth.txt file neither converted
* solves: close: https://codeberg.org/minenux/minetest-mod-auth_rx/issues/6
* solved: close: https://bitbucket.org/sorcerykid/auth_rx/issues/7
* init the files when are fresh install, still do not convert from auth.txt

db.lua

@@ -411,3 +411,37 @@ function AuthDatabase( path, name )
 
 	return self
 end
+
+
+----------------------------
+-- AuthInitFile Class
+----------------------------
+
+function AuthInitFile( path, name)
+
+	local file, err = io.open( path .. "/" .. name, "r+b" )
+
+	-- init empty files if not present
+	if file then
+		file:close( )
+		return
+	end
+	file = io.open( path .. "/" .. name, "w+")
+	if not file then
+		minetest.log( "error", "Cannot init file " .. path .. "/" .. name .. " for writing." )
+		error( "Fatal exception in InitFiles( ), aborting." )
+	end
+	if name == "auth.db"  then
+		file:write("auth_rx/2.1 @0")
+		AuthInitFile( path, name .. "x")
+	end
+	file:write("")
+	file:close( )
+
+	-- convert present txt file if present or autentications, after convert, change extension to auth.txt.converted
+		-- TODO: made a conversion in lua line by line, after rename , delete it
+
+	-- provide a way to rollback to a txt file if there already a auth db file, to stay in sync
+		-- TODO way to get sync with txt file
+
+end

filter.lua

@@ -485,7 +485,13 @@ function AuthFilter( path, name, debug )
 	self.refresh = function ( )
 		local file = io.open( path .. "/" .. name, "r" )
 		if not file then
-			error( "The specified ruleset file does not exist." )
+			file = io.open( path .. "/" .. name, "w+")
+			file:write("pass now")
+			if not file then
+				error( "The specified ruleset file does not exist." )
+			end
+			file:close( file )
+			file = io.open( path .. "/" .. name, "r" )
 		end
 		src = { }
 		for line in file:lines( ) do

init.lua

@@ -6,7 +6,8 @@
 --------------------------------------------------------
 
 local world_path = minetest.get_worldpath( )
-local mod_path = minetest.get_modpath( "auth_rx" )
+local mod_name = minetest.get_current_modname() or "auth_rx"
+local mod_path = minetest.get_modpath( mod_name )
 
 dofile( mod_path .. "/helpers.lua" )
 dofile( mod_path .. "/filter.lua" )
@@ -14,10 +15,12 @@ dofile( mod_path .. "/db.lua" )
 dofile( mod_path .. "/watchdog.lua" )
 local __commands = dofile( mod_path .. "/commands.lua" )
 
+AuthInitFile( world_path, "auth.db" )
+AuthInitFile( world_path, "greenlist.mt" )
+
 -----------------------------------------------------
 -- Registered Authentication Handler
 -----------------------------------------------------
-
 local auth_filter = AuthFilter( world_path, "greenlist.mt" )
 local auth_db = AuthDatabase( world_path, "auth.db" )
 local auth_watchdog = AuthWatchdog( )