Elevator Call Button

--Elevator Call Button
--Version 2.2
local updateCode = "7EusNXVa";

local elevatorNumberFile = fs.open("elevatorNumber.dat", "r"); --Gets the elevator number from file.
local elevatorNumber = tonumber(elevatorNumberFile.readAll());
elevatorNumberFile.close();

local floorNumberFile = fs.open("floorNumber.dat", "r"); --Gets the floor number from file.
local floorNumber = tonumber(floorNumberFile.readAll());
floorNumberFile.close();

local protocol = "ELEVATOR" .. elevatorNumber;
local hostname = "callbutton" .. floorNumber;
local elevatorController;

local uptime = 0;
while true do
    rednet.open("bottom");
    elevatorController = rednet.lookup(protocol, "elevator_controller");
    if elevatorController ~= nil then
        break;
    end
end

term.clear();
term.setCursorPos(1,1);


function update()
    shell.run("pastebin", "get", updateCode, "download");
    if fs.exists("download") then
        fs.delete("startup.lua");
        fs.copy("download", "startup.lua");
        fs.delete("download");
        return true;
    else
        return false;
    end
end

local status = "idle";

function exit()
    error("Exiting Program.")
end

function formatTime() --Format seconds into readable time
    local days = math.floor(uptime/86400)
    local hours = math.floor((uptime % 86400)/3600)
    local minutes = math.floor((uptime % 3600)/60)
    local seconds = math.floor((uptime % 60))
    return string.format("%02d:%02d:%02d:%02d",days,hours,minutes,seconds)
end

function countTime() --Function keeping track of uptime.
    while true do
        uptime = uptime + 1;
        sleep(1);
    end
end

function log(inputText) --print out message with timestamp
    print("[" .. formatTime(uptime) .. "] " .. inputText);
end

function alertLight()
    redstone.setOutput("back", true);
    sleep(.5);
    redstone.setOutput("back", false);
    sleep(.5);
end

function mainLoop()
    while true do
        if status == "idle" then
            if redstone.getInput("back") == true then
                status = "active";
                rednet.send(elevatorController, floorNumber, protocol);
            end
        end
        sleep(.5);
    end
end

function network()
    rednet.host(protocol, hostname)
    log("Started.")
    while true do
        local from, message = rednet.receive(protocol);
        if message == "status" then
            log("Recieved Request for Status.")
            rednet.send(from, true, protocol);
        elseif message == "idle" then
            log("Recieved Request to set to idle")
            status = "idle";
            rednet.send(from, true, protocol);
        elseif message == "active" then
            log("Recieved Request to set to active")
            status = "active";
            rednet.send(from, true, protocol);
        elseif message == "update" then
            rednet.send(from, true, protocol);
            rednet.send(from, update(), protocol);
            os.reboot();
        elseif message == "restart" then
            os.reboot();
        end
    end
end

parallel.waitForAll(mainLoop, network, countTime);