Unworking door lock/unlock

-- Passlock v0
-- (C) 2012 User 'Advert' at http://www.computercraft.info/forums2/
-- X11/mit licence (use/modify at your will, but please, leave credit where due)

-- Settings.
local dConfig = {} -- Marking defaults, so we can revert to them easily.

do -- Because I like do statements.
    dConfig["sUserPassword"]    = "open"
    dConfig["sRootPassword"]    = "2good4u"
    dConfig["nOpenTime"]        = 3 -- Number of seconds to keep the door open.
    dConfig["nUserPassFailLock"]= 3 -- Number of user password fails before lock. (0 = disable, 1 = 1 fail, 2 = 2 fails, etc.) Reset at success (root can still login)
    dConfig["nUserPassFailLockDuration"] = 15 -- Number of seconds to lock after nUserPassFailLock password fails
    dConfig["bRootForceOpen"] = false -- Door is forced open by Root user.
    dConfig["bLockAtStartup"] = true -- This will lock the computer for nUserPassFailLockDuration seconds at startup, to prevent bypassing of nUserLockPassFailLock.
    dConfig["sRedstoneSide"] = "back" -- The side the redstone is at.
    -- Stuff not stored here: door state, etc.
end
-- small helper function ;_;
local function copyTable(o)
    -- Will simply copy a table, non-recursively.
    local t = {}
    for k, v in pairs(o) do t[k] = v end
end

local config = copyTable(dConfig)

-- Misc functions

local function mergeTable(t1, t2)
    -- This function puts everyting in t2 into t1.
    for k, v in pairs(t2) do
        t1[k] = v
    end
    return t1 -- We return t1 because that's the table you'll want afterwards (even though it doesn't make a new table)
end

-- Major functions
-- Making functions local (I don't like messing up _G)
local renderDisplay, checkEvents, loadFromFile, saveToFile

-- Core loop components
function renderDisplay()
    term.clear()
    term.setCursorPos(1,1)
    --TODO
end

--
function checkEvents()
    -- Used in our loop to check for new OS events.
    local event, p1, p2 = os.pullEvent()
    --TODO
    print("Event: ", event, "\n p1 & p2: ", p1, ",", p2)
    if event == "char" then
        if p1 == "x" then
            error("User pressed 'x'. 'x' is a bad key to press.")
        elseif p1 == "s" then
            saveToFile()
            loadFromFile()
        end
    end

end

function checkDoorTimer()

end

function checkUserLockTimer()

end

-- Door toggler.
function toggleDoor(bState)
    -- This will toggle the door, or set it's state to bState
    if bState ~= nil then
        bDoorState = bState
    else
        bDoorState = not bDoorState -- not negates the state in boolean: true, any data not nil -> false; false, nil -> true
    end
    return bDoorState -- Good practice to return result, in this case the door's state.
end



-- Saving/loading
do -- This just to make the code neater, really. (And so I can easily collapse the code in ScITE)

    function loadFromFile()
        if not fs.exists("passlock-data") then return end -- We can't load nothing.
        local err, res = pcall(dofile, "passlock-data") -- Yes, I'm doing this the easy and hard way.
        if err then
            print("Error loading configuration: \n", res)
            print("Enter to continue...")
            read()
        end
        mergeTable(config, res) -- This will ensure the defaults are there if a field is missing.
    end

    -- Saving helper format strings
    local saveAs = {}
    saveAs.boolean = [[config[%q] = %s]]
    saveAs.string = [[config[%q] = %q]]
    saveAs.number = [[config[%q] = %d]]

    -- Saving function
    function saveToFile()
        -- This is the 'harder' part of the two :(

        local sData = [[local config = {} -- This file, generated by Passlock. Edit at your own risk.\n]]

        for k, v in pairs(config) do
            local sDataType = type(v)
            local sSaveHelper = saveHelper[sDataType]
            if not sSaveHelper then
                -- We have problem, let's just print it, and continue without saving it.
                print("Warning: (saveToFile) unknown data type, in key: " .. k)
            else
                -- No errors, save it.
                sData = sData .. string.format(sSaveHelper, k, v) .. "\n"
            end
        end

        sData = sData .. [[return config]] -- We need to return the config in order to retrieve it.

        -- Delete and save.
        if fs.exists("passlock-data") then
            fs.delete("passlock-data")
        end
        local hHandle = fs.open("passlock-data", "w")
        if not hHandle then
            -- We're pissed, let's error.
            error("Unable to open file handle; call to saveToFile", 2)
        end
        hHandle:write(sData)
        hHandle:close()
    end
end

-- Looping function

function doImportantStuff()
    while true do
        if bRootExit then -- Quit if user logged in as Root wishes to.
            break
        end
        checkDoorTimer() -- Lock the door if it has been open long enough
        checkUserLockTimer() -- Allow user to login again, if enough time has passed.
        --renderDisplay() -- We need to see something.
        checkEvents() -- Get our user input, or yet another timer event for updating the screen.
        -- Doesn't seem like much, does it? D:
    end
end




-- Loop
while true do
    local err, res = pcall(doImportantStuff)
    if bRootExit then -- Quit if user logged in as Root wishes to.
        break
    end
    if err ~= true then
        print("error: ", string.format("%q", res))
        print("enter to continue... (ctrl-t is SUPER EFFECTIVE right now!)")
        read()
    end
end