init-scripts 1.0

--[[
    init-scripts 1.0
    Written by Forairan

    init-scripts is a startup program that allows execution of several startup
    programs in different files, all without them interfering with each other.

    To write an init-script, just write a standard ComputerCraft Lua program,
    and stick it in /init-scripts/. Please follow the standard naming convention
    of "00_script", where "00" is the priority (lower numbered scripts get loaded
    earlier in the boot process), and "script" is the purpose/name of your script.
    Once put in the /init-scripts/ directory, the script will automatically run
    on any computer with init-scripts installed.

    To disable an init-script, you don't need to completely delete it - just append
    a ".disabled" suffix to it. For example, "00_script" will be executed, while
    "00_script.disabled" will not. The disabling functionality can be enabled/disabled
    using the configuration section below.

    Another security option is verbose mode, which prints the name of each
    script as it is being executed. You can also do an "interactive boot"
    by pressing ALT within 1 second of starting the computer. This allows you to select
    exactly what will be loaded and what will not be loaded.
    The interactive boot feature can be disabled via a configuration option below.
]]--

-- Configuration Section
--[[
    Allows or disallows script disabling.

    true: Allow script disabling
    false: Disallow script disabling
]]--
local allowScriptDisabling = true

--[[
    Enables or disables verbose mode, where init-scripts prints the name of each
    scripts as it is being executed.

    true: Enable verbose mode
    false: Disable verbose mode
]]--
local verboseMode = true

--[[
    Enables or disables the ability to boot interactively - as in, choose which scripts
    will execute and which will not.
    If this option is enabled, you can press "ALT" within 1 second while the computer boots
    to enter interactive mode.

    true: Allow entering interactive mode
    false: Disallow entering interactive mode
]]--
local allowInteractiveMode = true

-- END OF USER-MODIFIABLE CODE

os.pullEvent = os.pullEventRaw
local usingInteractiveMode = false

-- Check to see if /init-scripts/ exists first.
if fs.isDir("/init-scripts") ~= true then
    fs.makeDir("/init-scripts")
end

-- Get a listing of all the scripts
local oldDir = shell.dir()
shell.setDir("/init-scripts")
local scriptList = fs.list("/init-scripts")
local oldShellEnv = getfenv(shell.run)

-- Interactive mode prompt
if allowInteractiveMode then
    print("Press ALT now to enter interactive mode.")
    os.startTimer(1)
    local event, p1, p2, p3 = os.pullEvent()
    if event == "key" and p1 == 56 then
        print("Performing interactive boot.")
        usingInteractiveMode = true
    end
end

-- Iterate through the listing and execute the scripts
for _,file in ipairs(scriptList) do
    skipped = false
    if allowScriptDisabling and not usingInteractiveMode then
        if string.sub(file, -9) == ".disabled" then
            if verboseMode then
                print("Not executing ".. file .." because it is disabled.")
            end
            skipped = true
        end
    end

    if usingInteractiveMode then
        -- Ask the user if we want to execute it
        local function promptUser()
            write("Execute '" .. file .. "'? (y/n) ")
            input = read()

            if input == "Y" or input == "y" then
                skipped = false
            elseif input == "N" or input == "n" then
                skipped = true
                print("Skipping.")
            else
                print("Invalid response.")
                promptUser()
            end
        end
        promptUser()
    end

    if skipped ~= true then
        -- Actually execute it
        if verboseMode or usingInteractiveMode then
            print("Executing ".. file)
        end

        -- Set the environment so nothing nasty happens
        local tEnv = {}
        setmetatable(tEnv, {__index = _G})
        setfenv(shell.run, tEnv)
        shell.run(file)
    end
end

-- Reset the shell.run environment
setfenv(shell.run, oldShellEnv)

-- We're done!
if verboseMode then
    print("init-scripts execution complete.")
end
shell.setDir(oldDir)