settings.lua

local expect = require "cc.expect"
local fs = require "fs"
local textutils = require "textutils"

local settings = {}

local store = {}
local definitions = {}

function settings.get(name, default)
    expect(1, name, "string")
    if store[name] ~= nil then return store[name]
    elseif default ~= nil then return default
    else return definitions[name] and definitions[name].default end
end

function settings.set(name, value)
    expect(1, name, "string")
    if value == nil then error("bad argument #2 (expected value, got nil)", 2) end
    if definitions[name] and definitions[name].type then expect(2, value, definitions[name].value) end
    store[name] = value
end

function settings.unset(name)
    expect(1, name, "string")
    store[name] = nil
end

function settings.define(name, opts)
    expect(1, name, "string")
    if opts ~= nil then
        expect(2, opts, "table")
        expect.field(opts, "description", "string", "nil")
        expect.field(opts, "type", "string", "nil")
        if opts.type then expect.field(opts, "default", opts.type, "nil") end
    end
    definitions[name] = opts or {}
end

function settings.undefine(name)
    expect(1, name, "string")
    definitions[name] = nil
end

function settings.getDetails(name)
    expect(1, name, "string")
    local t = definitions[name]
    if t then return {description = t.description, default = t.default, type = t.type, value = store[name]}
    else return {value = store[name]} end
end

function settings.clear()
    store = {}
end

function settings.getNames()
    local retval = {}
    for k in pairs(definitions) do retval[#retval+1] = k end
    table.sort(retval)
    return retval
end

function settings.load(path)
    path = expect(1, path, "string", "nil") or "/etc/settings"
    if not fs.exists(path) then return false end
    local file = fs.open(path, "r")
    if not file then return false end
    local ok, data = pcall(textutils.unserialize, file.readAll())
    file.close()
    if not ok or type(data) ~= "table" then return false end
    for k, v in pairs(data) do store[k] = v end
    return true
end

function settings.save(path)
    path = expect(1, path, "string", "nil") or "/etc/settings"
    local file = fs.open(path, "r")
    if not file then return false end
    file.write(textutils.serialize(store))
    file.close()
    return true
end

-- Set default settings
settings.define("shell.allow_startup", {
    default = true,
    description = "Run startup files when the computer turns on.",
    type = "boolean",
})
settings.define("shell.allow_disk_startup", {
    default = true,
    description = "Run startup files from disk drives when the computer turns on.",
    type = "boolean",
})

settings.define("shell.autocomplete", {
    default = false,
    description = "Autocomplete program and arguments in the shell.",
    type = "boolean",
})
settings.define("edit.autocomplete", {
    default = false,
    description = "Autocomplete API and function names in the editor.",
    type = "boolean",
})
settings.define("lua.autocomplete", {
    default = false,
    description = "Autocomplete API and function names in the Lua REPL.",
    type = "boolean",
})

settings.define("edit.default_extension", {
    default = "lua",
    description = [[The file extension the editor will use if none is given. Set to "" to disable.]],
    type = "string",
})
settings.define("paint.default_extension", {
    default = "nfp",
    description = [[The file extension the paint program will use if none is given. Set to "" to disable.]],
    type = "string",
})

settings.define("list.show_hidden", {
    default = false,
    description = [[Show hidden files (those starting with "." in the Lua REPL).]],
    type = "boolean",
})

settings.define("motd.enable", {
    default = true,
    description = "Display a random message when the computer starts up.",
    type = "boolean",
})
settings.define("motd.path", {
    default = "/rom/motd.txt:/motd.txt",
    description = [[The path to load random messages from. Should be a colon (":") separated string of file paths.]],
    type = "string",
})

settings.define("lua.warn_against_use_of_local", {
    default = true,
    description = [[Print a message when input in the Lua REPL starts with the word 'local'. Local variables defined in the Lua REPL are be inaccessable on the next input.]],
    type = "boolean",
})
settings.define("lua.function_args", {
    default = true,
    description = "Show function arguments when printing functions.",
    type = "boolean",
})
settings.define("lua.function_source", {
    default = false,
    description = "Show where a function was defined when printing functions.",
    type = "boolean",
})
settings.define("bios.strict_globals", {
    default = false,
    description = "Prevents assigning variables into a program's environment. Make sure you use the local keyword or assign to _G explicitly.",
    type = "boolean",
})
settings.define("shell.autocomplete_hidden", {
    default = false,
    description = [[Autocomplete hidden files and folders (those starting with ".").]],
    type = "boolean",
})
settings.define("bios.use_multishell", {
    default = true,
    description = [[Allow running multiple programs at once, through the use of the "fg" and "bg" programs.]],
    type = "boolean",
})

settings.load()

return settings