Network Management Server

--DevelopedLogic's Network Management Server (NMS)
--This is the equivalent of a real DNS server, however may become much more

os.loadAPI("/dniconf")
modemSide = dniconf.modemSide
DNIPort = dniconf.DNIPort
networkName = dniconf.networkName

modem = peripheral.wrap(modemSide)

if modem.isWireless() then
    error("YOU MAY NOT USE NMS ON A WIRELESS NETWORK AS TOO MANY MODEM MESSAGES PASS BY!")
end

if not fs.exists("/domains") then
    fs.makeDir("/domains")
    print("Created domain directory")
end

if not fs.exists("/ids") then
    fs.makeDir("/ids")
    print("Created id directory")
end

termW, termH = term.getSize()

term.setPaletteColor(colours.blue, 0, 0, 1)

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

topBar = window.create(term.current(), 1, 1, termW, 1, true)
bottomBar = window.create(term.current(), 1, termH, termW, 1, true)
centre = window.create(term.current(), 1, 2, termW, termH-2, true)

topBar.setBackgroundColour(colours.lightGrey)
topBar.setTextColour(colours.blue)
topBar.clear()
bottomBar.setTextColour(colours.blue)
bottomBar.setBackgroundColour(colours.lightGrey)
bottomBar.clear()
centre.setTextColour(colours.lightGrey)
centre.setBackgroundColour(colours.blue)
centre.clear()

topBar.setCursorPos(1,1)
topBar.write("Network Management Server - "..networkName)
bottomBar.setCursorPos(1,1)
bottomBar.write("Run nmsconfig to manage domains")

term.redirect(centre)

modem.open(DNIPort)

function stok(data)
    if type(data) == "string" then
        return true
    else
        return false
    end
end

function numok(data)
    if type(data) == "number" then
        return true
    else
        return false
    end
end

function fail(gotoid)
    print("Fail from "..gotoid)
    print()
    data = {gotoid, "failed"}
    modem.transmit(DNIPort, DNIPort, textutils.serialise(data))
end

function pass(val, gotoid)
    print("Pass from "..gotoid)
    print()
    data = {gotoid, val}
    modem.transmit(DNIPort, DNIPort, textutils.serialise(data))
end

function getdomain(id, goto)
    print(goto.." Requested "..id)
    if not fs.exists("/domains/"..id) then
        fail(goto)
    else
        file = fs.open("/domains/"..id, "r")
        pass(file.readLine(), goto)
        file.close()
    end
end

function getid(domain, goto)
    print(goto.." Requested "..domain)
    if not fs.exists("/ids/"..domain) then
        fail(goto)
    else
        file = fs.open("/ids/"..domain, "r")
        pass(file.readLine(), goto)
        file.close()
    end
end

function run(msg)
    data = textutils.unserialise(msg)
    if data ~= nil and #data == 4 and stok(data[1]) and stok(data[2]) and stok(data[3]) and numok(data[4]) and data[1] == "nmsreq" then
        if data[2] == "domain" then
            getdomain(data[3], data[4])
        elseif data[2] == "id" then
            getid(data[3], data[4])
        end
    end
end

while true do
    message = { os.pullEvent("modem_message") }
    run(message[5])
end