urfs.lua

-- Copyright (C) 2022 Ross Grams
--
-- This module is free software; you can redistribute it and/or
-- modify it under the terms of the MIT license.

local M = {}

local ffi = require "ffi"
local C = ffi.os == "Windows" and ffi.load("love") or ffi.C

ffi.cdef[[
int          PHYSFS_mount(const char *newDir, const char *mountPoint, int appendToPath);
int          PHYSFS_unmount(const char * oldDir);
const char * PHYSFS_getWriteDir(void);
int          PHYSFS_setWriteDir(const char * newDir);
const char * PHYSFS_getLastError(void);
]]

local mountedAs = {}

local function getLastErrorMessage()
	return ffi.string(C.PHYSFS_getLastError())
end

function M.mount(archive, mountPoint, appendToPath)
	if C.PHYSFS_mount(archive, mountPoint, appendToPath and 1 or 0) == 0 then
		return false, getLastErrorMessage()
	end
	if not mountedAs[archive] then
		mountedAs[archive] = mountPoint or ""
	end
	return true
end

function M.unmount(archive)
	if C.PHYSFS_unmount(archive) == 0 then
		return false, getLastErrorMessage()
	end
	mountedAs[archive] = nil
	return true
end

function M.getMountPoint(archive)
	return mountedAs[archive]
end

function M.setWriteDir(dir)
	if C.PHYSFS_setWriteDir(dir) == 0 then
		return false, getLastErrorMessage()
	end
	return true
end

function M.getWriteDir()
	local r = C.PHYSFS_getWriteDir()
	if r == nil then -- A NULL pointer returned from FFI is not falsy, but == nil.
		return love.filesystem.getSaveDirectory()
	end
	return ffi.string(r)
end

return M