OpenPeripherals, TE Redstone Cells, coroutines, oh my.

-- Based
-- A base monitoring and control daemon
os.loadAPI("lib/tcolor")

local args = { ... }

if #args ~= 1 then
  print("Usage: based <side>")
  return
end

-- Wrap the monitor to that side.
monitor = peripheral.wrap(args[1])
if monitor == nil then
  print("Side must exist.")
  return
end

-- Main function to handle events.
function event_handler()
  while true do
    event = {coroutine.yield()}
    if event[1] == "key" then
      if event[2] == keys.q then
        break
      end
    elseif event[1] == "op_tick_sync" then
      os.queueEvent(unpack(event))
    end
  end
end

-- Show the header of the program.
function display_header()
  x, y = monitor.getSize()
  for i=1,x do
    monitor.setCursorPos(i, 1)
    tcolor.write(monitor, " ", colors.blue, colors.blue)
  end
  monitor.setCursorPos(1, 1)
  tcolor.write(monitor, "Base Monitor", colors.black, colors.blue)
end

function display_info()
  while true do 
    coroutine.yield()
    monitor.clear()
    display_header()

    -- Keep from flickering.
    sleep(0.2)
  end
end

-- Plugin architecture.
local cblist = {}

function add_cb(f)
  table.insert(cblist, f)
end

function load_plugins(list)
  for c, item in pairs(list) do
    print("trying to load plugin "..item)
    os.loadAPI("bin/bdplugins/"..item)
    _G[item].plugin_setup(cblist)
  end
  print("plugins loaded")
end

-- Plugins register callbacks to the plugin manager.
function run_plugins()
  print("loading plugins")
  load_plugins(fs.list("bin/bdplugins"))
  while true do
    local event = {coroutine.yield()}
    print("Plugins running")
    for i,item in pairs(cblist) do 
      item(event, monitor)
    end
  end
end

local eventRoutine = coroutine.create(event_handler)
local displayRoutine = coroutine.create(display_info)
local pluginRoutine = coroutine.create(run_plugins)

local event = {}

while true do
  -- launch the coroutines with specific events
  coroutine.resume(eventRoutine, unpack(event))
  coroutine.resume(displayRoutine, unpack(event))
  coroutine.resume(pluginRoutine, unpack(event))

  -- Add an event to keep going
  os.queueEvent("idle")
  if coroutine.status(eventRoutine) == "dead" then
    break
  end

  event = { os.pullEvent() }
end
monitor.clear()

function plugin_setup(callbacks)   
  table.insert(callbacks, display_power)
end

function test(event, monitor)
  --print("test!")
  tcolor.write(monitor, "Testing", colors.white, colors.black)
end

function display_power(event, monitor)
  print("test")
  thermxp = "tile_thermalexpansion_cell_reinforced_name_1"
  bigr = "BigReactors-Reactor_0"
  local cell = peripheral.wrap(thermxp)
  if cell == nil then print("cell not found") end
  print("getting power")
  total = cell.getEnergyStored() -- This does not work.
  print(total)
  -- total = 5
  print("got total")
  x, y = monitor.getCursorPos()
  monitor.setCursorPos(1, y+1)
  tcolor.write(monitor, total, colors.white, colors.black)
end