ComputerCraft MFSU Monitor

-- pastebin get 0X93VE9M mfsumon
-- http://www.computercraft.info/forums2/index.php?/topic/16109-mfsu-monitor/

--[[
* Pad the left side of a string x number of times
]]
local function padLeft(str, w)
  return string.rep(" ", w - #str) .. str
end

--[[
* Locate the nearest
]]
local function findPeripheral(_type)
  for _,name in pairs(peripheral.getNames()) do
    if peripheral.getType(name) == _type then
      return peripheral.wrap(name)
    end
  end
end

-- Locate the nearest monitor and power sources
local m = findPeripheral("monitor")

-- Error catches
if not m then
  error("Cannot find monitor attached to this computer", 0)
end

m.setTextScale(0.5)

local w, h = m.getSize()
local totalCap = 0
local totalStore = 0
local percent = 0
local mfsu

os.startTimer(1)

while true do
  -- Start getting numbers

  totalCap = 0
  totalStore = 0
  percent = 0

  for k,v in pairs(peripheral.getNames()) do
    if peripheral.getType(v) == "mfsu" then
	  -- Increment the storage and capacity
	  mfsu = peripheral.wrap(v)
	  totalCap = totalCap + mfsu.getEUCapacity()
	  totalStore = totalStore + mfsu.getEUStored()
	end
  end

  -- Calculate a percentage
  percent = math.ceil(totalStore / totalCap) * 100


  m.clear()
  m.setCursorPos(1, 2)
  m.setTextColour(colours.orange)
  m.write("Avail EU: ")
  m.setTextColour(colours.white)
  m.write(tostring(percent) .. "%")


  -- If available power is 75% of more, turn redstone on
  if percent > 75 then
    redstone.setOutput("right", false)
	m.setCursorPos(1, 4)
    m.setTextColour(colours.orange)
    m.write("Redstone: ")
    m.setTextColour(colours.white)
    m.write("Off")
  end

  -- If power falls below 15%, turn redstone off
  if percent < 15 then
    redstone.setOutput("right", true)
	m.setCursorPos(1, 4)
    m.setTextColour(colours.orange)
    m.write("Redstone: ")
    m.setTextColour(colours.white)
    m.write("On")
  end

  os.pullEvent("timer")
  os.startTimer(1)
end