tanks

-- Valve, Monitor & Wireless Modem
local nir = peripheral.wrap("right")
local mon = peripheral.wrap("top")
local wmod = peripheral.wrap("back")

local warning = 25          -- Warning level in %
local cap                   -- Tank capacity
local amount                -- Amount liquid in tank
local percentFull           -- Percent liquid in tank
local lastPercent = 1000    -- Percent last loop
local sendMsg               -- Message to send
local sleepTime             -- How long to sleep
local sendFreq              -- Modem Tx Frequency
local content = liquidType  -- What is in tank?
-- Make sure frequency match the main computer

-- grab data values
a,b,c,data = nir.get(1)
if data["liquidId"] == 11
  then
    liquidType = "Lava"
    sendFreq = "3"
elseif data["liquidId"] == 255
  then
    liquidType = "Oil"
    sendFreq = "4"
elseif data["liquidId"] == 4064
  then
    liquidType = "Fuel"
    sendFreq = "5"
else
  liquidType = "Unknown"
  sendFreq = "6"
end

-- Set warning lamp to off
redstone.setOutput("left", false)


-- Main prog loop, never stop
while true do
  mon.clear()
  mon.setCursorPos(1,1)

  -- Get values for tank capacity and amount
  cap = data["capacity"]
  amount = data["amount"]

  -- If tank is empty, to avoid math issues with 0
  if amount == nil then
    amount = 0
    percentFull = 0
  else

    -- Use math.floor to convert to integers
    percentFull = math.floor(100 * amount / cap)
  end

  -- Self explanatory :)
  mon.write(content)
  mon.setCursorPos(1,2)
  mon.write("Amount: " ..amount .."/"..cap .." mB.")
  mon.setCursorPos(1,3)
  mon.write("Amount: " ..percentFull .."%  ")

  -- Check for change since last loop
  if percentFull == lastPercent then
    print("Still " ..percentfull .. "%, nothing sent.")
  else
    -- If value changed, send to main!
    sendmsg = content ..": " ..percentFull .." %"
    wmod.transmit(sendFreq,"0",sendmsg)
    print("Sent: " ..sendmsg)
  end

  -- Save for next loop
  lastPercent = percentFull

  -- Warning control, local lamp
  mon.setCursorPos(1,5)

  if percentFull < warning then
    redstone.setOutput("left", true)
    mon.write("Less than " ..warning .."% full")
    sleep(1)
    redstone.setOutput("left", false)
    sleeptime = 1
  else
    -- Above warning level, sleep longer
    mon.write("More than " ..warning .."% full")
    sleeptime = 5
  end

  -- Sleep either 1 or 10 seconds
  sleep(sleeptime)
end