check

-- Config
local iLevel = 5           -- Securitylevel of this station
local iLevelLength = 6     -- length of a security level key
local sRsOutput = "bottom" -- Redstone output for the door
local iOpenTime = 3        -- amount of seconds the door should be open when opened from within
-- End of config

term.clear()
term.setCursorPos(1,1)
local hMKey = fs.open("masterkey", "r")
local sMKey = hMKey.readAll()
local sLevelMasterKey = string.sub(sMKey, iLevel*iLevelLength, (iLevel*iLevelLength) + iLevelLength)
local iCurrentOpenTime = 0

local bDebug = true
local tTID = os.startTimer(1)

hMKey.close()

function clear()
  term.clear()
  term.setCursorPos(1,1)
  print("Press enter to open the door")
  print(sLevelMasterKey)
end

clear()
while (true) do
  local eEvent, cParam1, cParam2 = os.pullEvent ()
  clear()

  if (bDebug) then
    print("---")
    print(tTID)
    print("---")
    print("event=" .. eEvent)
    if (cParam1 ~= nil) then
          print("par1=" .. cParam1)
    end
    print("---")
    print("openTime=" .. iCurrentOpenTime)
    print("---")
  end

  if eEvent == "key" then
    rs.setOutput(sRsOutput, true)
    sleep(iOpenTime)
    rs.setOutput(sRsOutput, false)
    tTID = os.startTimer(1)
  else
    tTID = os.startTimer(1)
  end
  if (fs.exists("disk/key")) then
    hFile = fs.open("disk/key", "r")
        sKey = hFile.readAll()
        if (bDebug) then
          print("ExpectedKey="..sLevelMasterKey)
          print("GivenKey="..sKey)
        end
        hFile.close()
        if (string.len(sKey) >= string.len(sLevelMasterKey)) then
          sLevelKey = string.sub(sKey, iLevel*iLevelLength, (iLevel*iLevelLength) + iLevelLength)
          if (sLevelKey == sLevelMasterKey) then
            iCurrentOpenTime = 1
          end
        end
  end

  if (iCurrentOpenTime > 0) then
    print("Door opened")
    rs.setOutput(sRsOutput, true)
  else
    rs.setOutput(sRsOutput, false)
  end
  iCurrentOpenTime = iCurrentOpenTime - 1
end