vs

local diskDriveSide = "left"

function RandomString()
  length = 16
  if length < 1 then return nil end
  local array = {}
  for i=1, length do
    array[i] = string.char(math.random(32,126))
 end
  return table.concat(array)
end

function compare()
  local disk_f = io.open("disk/pw.txt", "r")
  if disk_f == nil then
    term.setCursorPos(1,4)
    print("File or code does not exist.")
    sleep(3)
   else
  local disk_pw = disk_f:read("*l")
  disk_f:close()
  local lastID_f = io.open("lastid.txt", "r")
  local lastID = lastID_f:read("*l")
  lastID_f:close()
  while true do
  term.setCursorPos(1,4)
  print("Checking..")
  sleep(0.3)
    for fileNumber = 1, lastID do
      print("Checking : "..fileNumber..".txt")
      local check_f = io.open(fileNumber..".txt","r")
      local line = check_f:read("*l")
      sleep(0.1)
    if line == disk_pw then
      local nick = check_f:read("*l")
      print("Username: " ..nick)
      print("Press any key to exit")
      os.pullEvent()
      return
    end
    end
    print("Invalid, press any key to exit.")
    os.pullEvent()
    return
end
end

function newID()
  local genCode = RandomString()
  if disk.isPresent(diskDriveSide) == false then
    term.setCursorPos(1,4)
    print("Insert Disk!")
    sleep(3)
   else
    term.setCursorPos(1,4)
    term.write("Please type in the player name : ")
    local playerName = read()
    disk.setLabel(diskDriveSide, "SPCard - " ..playerName)
    local disk_pw = io.open("disk/pw.txt", "w")
    disk_pw:write(genCode)
    disk_pw:close()
    local root_lastID = io.open("lastid.txt","r")
    local lastID = root_lastID:read("*l")
    root_lastID:close()
    root_lastID = io.open("lastid.txt","w")
    newID = lastID+1
    root_lastID:write(newID)
    root_lastID:close()
    local root_newID = io.open(newID..".txt","w")
    root_newID:write(genCode)
    root_newID:write("\n")
    root_newID:write(playerName)
    root_newID:close()
    term.setCursorPos(1,6)
    print("Generated!")
    sleep(2)
  end
  end
end

function mainMenu()
  term.clear()
  term.setCursorPos(1,1)
  print("1. Verify")
  print("2. Make New ID Card")
  local event, key = os.pullEvent("char")
  if key == "1" then
     if disk.isPresent(diskDriveSide) == false then
        term.setCursorPos(1,4)
        print("Insert Disk!")
        sleep(3)
      else
       compare()
     end
   elseif key == "2" then
     newID()
   else
     sleep(0.1)
 end
end

while true do
  mainMenu()
end