Update lua FileSystem to use URI based parameters and allow opening o…

…f files and creation of directories

Rather than passing a Root field we use a URI, with either a "data" or "user" scheme to indicate where they are working

Add a MakeDirectory method
Add a Open method that returns a lua io file interface
Also add a redacted lua io interface.
Add a FileSystem.lua with meta stubs for lint/hinting.

data/meta/Constants.lua

@@ -64,9 +64,6 @@
 -- A <Constants.DetailLevel> string
 ---@class DetailLevel: string
 
--- A <Constants.FileSystemRoot> string
----@class FileSystemRoot: string
-
 -- A <Constants.PiGuiFaceFlags> string
 ---@class PiGuiFaceFlags: string
 
@@ -147,9 +144,6 @@ Constants.BodySuperType = {}
 ---@type DetailLevel[]
 Constants.DetailLevel = {}
 
----@type FileSystemRoot[]
-Constants.FileSystemRoot = {}
-
 ---@type PiGuiFaceFlags[]
 Constants.PiGuiFaceFlags = {}
 

data/meta/FileSystem.lua

@@ -0,0 +1,49 @@
+-- Copyright © 2008-2023 Pioneer Developers. See AUTHORS.txt for details
+-- Licensed under the terms of the GPL v3. See licenses/GPL-3.txt
+
+-- This file implements type information about C++ classes for Lua static analysis
+-- This is used in FileSyestem.lua whcih then extends that.
+
+---@meta
+
+---@class FileSystem
+local FileSystem = {}
+
+---@param path string The directory to read the contents of.
+---@return string[] files  A list of files as full paths from the root
+---@return string[] dirs   A list of dirs as full paths from the root
+---
+--- Example:
+---  > local files, dirs = FileSystem.ReadDirectory("user://savefiles")
+function FileSystem.ReadDirectory(path) end
+
+--- Join the passed arguments into a path, correctly handling separators and .
+--- and .. special dirs.
+---
+---@param arg string[]  A list of path elements to be joined
+---@return string       The joined path elements
+function FileSystem.JoinPath( ... ) end
+
+---@param dir_name string The name of the folder to create
+---@return boolean Success
+function FileSystem.MakeDirectory( dir_name ) end
+
+--- Wrapper for our patched io.open that ensures files are opened inside the sandbox.
+--- Prefer using this to io.open
+---
+--- Files in the user folder can be read or written to
+--- Files in the data folder are read only.
+---
+---
+---
+--- Example:
+--- > f = FileSystem.Open( "user://my_file.txt", "w" )
+--- > f:write( "file contents" )
+--- > f:close()
+--- 
+---@param filename string   The name of the file to open, must start either user:// or data://
+---@param mode string|nil   The mode to open the file in, defaults to read only. Only user location files can be written
+---@return file             A lua io file
+function FileSystem.Open( filename ) end
+
+return FileSystem

data/modules/AutoSave/AutoSave.lua

@@ -6,7 +6,7 @@ local FileSystem = require 'FileSystem'
 local max_autosaves = 9
 
 local function PickNextAutosave()
-	local ok, files, _ = pcall(FileSystem.ReadDirectory, 'USER', 'savefiles')
+	local ok, files, _ = pcall(FileSystem.ReadDirectory, 'user://savefiles')
 	if not ok then
 		print('Error picking auto-save')
 		return '_autosave1'

data/pigui/modules/saveloadgame.lua

@@ -105,7 +105,8 @@ local function displaySave(f)
 end
 
 local function showSaveFiles()
-	local ok, files, _ = pcall(FileSystem.ReadDirectory, "USER","savefiles")
+	-- TODO: This is reading the files of disc every frame, think about refactoring to not do this.
+	local ok, files, _ = pcall(FileSystem.ReadDirectory, "user://savefiles")
 	if not ok then
 		print('Error: ' .. files)
 		saveFileCache = {}

src/enum_table.cpp

@@ -238,12 +238,6 @@ const struct EnumItem ENUM_DetailLevel[] = {
 	{ 0, 0 },
 };
 
-const struct EnumItem ENUM_FileSystemRoot[] = {
-	{ "USER", int(LuaFileSystem::ROOT_USER) },
-	{ "DATA", int(LuaFileSystem::ROOT_DATA) },
-	{ 0, 0 },
-};
-
 const struct EnumItem ENUM_PiGuiFaceFlags[] = {
 	{ "RAND", int(PiGui::Face::RAND) },
 	{ "MALE", int(PiGui::Face::MALE) },
@@ -325,7 +319,6 @@ const struct EnumTable ENUM_TABLES[] = {
 	{ "BodyType", ENUM_BodyType },
 	{ "BodySuperType", ENUM_BodySuperType },
 	{ "DetailLevel", ENUM_DetailLevel },
-	{ "FileSystemRoot", ENUM_FileSystemRoot },
 	{ "PiGuiFaceFlags", ENUM_PiGuiFaceFlags },
 	{ "ModelDebugFlags", ENUM_ModelDebugFlags },
 	{ "CruiseDirection", ENUM_CruiseDirection },
@@ -355,7 +348,6 @@ const struct EnumTable ENUM_TABLES_PUBLIC[] = {
 	{ "BodyType", ENUM_BodyType },
 	{ "BodySuperType", ENUM_BodySuperType },
 	{ "DetailLevel", ENUM_DetailLevel },
-	{ "FileSystemRoot", ENUM_FileSystemRoot },
 	{ "PiGuiFaceFlags", ENUM_PiGuiFaceFlags },
 	{ "ModelDebugFlags", ENUM_ModelDebugFlags },
 	{ "CruiseDirection", ENUM_CruiseDirection },

src/enum_table.h

@@ -34,7 +34,6 @@ extern const struct EnumItem ENUM_PolitGovType[];
 extern const struct EnumItem ENUM_BodyType[];
 extern const struct EnumItem ENUM_BodySuperType[];
 extern const struct EnumItem ENUM_DetailLevel[];
-extern const struct EnumItem ENUM_FileSystemRoot[];
 extern const struct EnumItem ENUM_PiGuiFaceFlags[];
 extern const struct EnumItem ENUM_ModelDebugFlags[];
 extern const struct EnumItem ENUM_CruiseDirection[];