help! Been up all night...

--
-- Control passive cooled Big Reactor ([url="http://big-reactors.com/"]http://big-reactors.com/[/url]).
--
-- Author: Cornmanv2
--
-- History:
--	 v0.1, 2015-07-30:
--		 first version
--
-- Remarks:
--	 Reactor API: [url="http://big-reactors.com/cc_api.html"]http://big-reactors.com/cc_api.html[/url]
--

--
-- Constant values (configuration)
--

-- Critical energy mark: give us the maximum power.
critEnergy=3000000

-- Low energy mark: turn reactor on to get more energy
lowEnergy=7000000

-- Heigh energy mark: we have enough, so turn the reactor off.
highEnergy=9000000


--
-- Calculate the control rod level (in %) by stored energy of internal
-- recator cell.
--
-- * If cellEnergy <= critEnergy, the calculation results in maximum
--   energy generation (control rod level = 0%).
-- * If cellEnergy >= highEnergy, the calculation results in 10% energy
--   generation (control rod level = 90%).
--
-- Parameters:
--	 cellEnergy - stored energy of internal cell in RF
--
-- Return:
--	 New control rod level in %.
--
function calcRodLevel(cellEnergy)
   -- Delta between critical and heigh energy mark
   local deltaEnergy = highEnergy - critEnergy

   -- Calculated maximum delta energy (not the real maximum), so that
   -- the high energy mark results into a control rod level of 90%
   local deltaEnergy100 = deltaEnergy * 100 / 90

   -- Energy for calculation: value between 0 and 'deltaEnergy'
   local calcEnergy = cellEnergy - critEnergy

   if calcEnergy < 0 then
	  calcEnergy = 0
   elseif calcEnergy > deltaEnergy then
	  calcEnergy = deltaEnergy
   end

   -- Calculate control rod level and round the result (math.floor + 0.5)
   return math.floor(calcEnergy * 100 / deltaEnergy100 + 0.5)
end


--
-- Write text with colors, if possible (advance monitor)
--
-- Parameters:
--	 mon   - handle of monitor
--	 color - text color
--	 text  - text to write
--
function writeColor(mon, color, text)
   if (mon.isColor()) then
	  mon.setTextColor(color)
   end
   mon.write(text)
   if (mon.isColor()) then
	  mon.setTextColor(colors.white)
   end
end


--
-- Display reactor status to a monitor.
--
-- Parameters:
--	 mon		- handle of monitor.
--	 state	  - state of reactor (on/off)
--	 rodLvl	 - Level of control rods in %
--	 cellEnergy - stored energy of internal cell (in RF)
--
function displayStatusToMonitor(mon, state, rodLvl, cellEnergy)
   mon.clear()

   -- First get the monitor size and try to scale, if the feature ist
   -- available.
   if mon.setTextScale ~= nil then
	  -- reset text scale
	  mon.setTextScale(1)
   end

   local width, height = mon.getSize()
   if width < 15 or height < 5 then
	  -- too small: try to scale down.
	  if mon.setTextScale ~= nil then
		 mon.setTextScale(0.5)
	  else
		 return -- too small und no text scale available
	  end

	  width, height = mon.getSize()
	  if width < 15 or height < 5 then
		 return -- still too small
	  end
   else
	  -- Huge monitors? Try to scale up, if possible (max scale=5).
	  local scale = math.min(width / 16, height / 5, 5)
	  scale = math.floor(scale * 2) / 2 -- multiple of 0.5

	  if scale > 1 and mon.setTextScale ~= nil then
		 mon.setTextScale(scale)
		 width, height = mon.getSize()
	  end
   end


   --
   -- Output the data
   --

   mon.setCursorPos(1,1)
   mon.write("Reactor")

   mon.setCursorPos(1,3)
   mon.write("Status ")

   if state then
	  writeColor(mon, colors.green, "ON")
   else
	  writeColor(mon, colors.red, "OFF")
   end

   mon.setCursorPos(1,4)
   mon.write("Rod Level: " .. rodLvl .. "%")

   mon.setCursorPos(1,5)
   if width < 16 then
	  mon.write("Cell: ") -- One block monitor (15x5 with scale 0.5)
   else
	  mon.write("Energy: ")
   end

   local c
   if cellEnergy < critEnergy then
	  c = colors.red -- Red: We use too much energy
   elseif cellEnergy > lowEnergy then
	  c = colors.green -- Green: More energy then low water mark
   else
	  c = colors.orange -- Orange: Less energy the low water mark, but OK
   end
   writeColor(mon, c, string.format("%d", math.floor(cellEnergy/1000 + 0.5)))
   mon.write(" kRF")
end


--
-- Display reactor status to any connected monitor and also to console.
--
-- Parameters:
--	 state	  - state of reactor (on/off)
--	 rodLvl	 - Level of control rods in %
--	 cellEnergy - stored energy of internal energy cell in RF
--
function displayStatus(state, rodLvl, cellEnergy)
   displayStatusToMonitor(term, state, rodLvl, cellEnergy) -- console
   term.setCursorPos(1,7)
   term.write("* Hold Crtl-T to terminate program")
   term.setCursorPos(1,8)

   local pList = peripheral.getNames()
   local i, name
   for i, name in pairs(pList) do
	  if peripheral.getType(name) == "monitor" then
		 -- found monitor as peripheral
		 displayStatusToMonitor(peripheral.wrap(name),
								state, rodLvl, cellEnergy)
	  end
   end
end


--
-- Find the first connected big reactor and return the wraped handle.
--
-- If no reactor was found this function terminate the program.
--
-- Return:
--	 Handle of first connected reactor found.
--
function getReactorHandle()
   local pList = peripheral.getNames()
   local i, name
   for i, name in pairs(pList) do
	  if peripheral.getType(name) == "BigReactors-Reactor" then
		 return peripheral.wrap(name)
	  end
   end

   error("No big reactor connected: Exit program")
   exit()
end


reactor = getReactorHandle()

--
-- Endless loop: Recalculate rod level, set rod level, display result
-- and wait for 5 secounds.
--
while true do
   cellEnergy = reactor.getEnergyStored()
   if cellEnergy < lowEnergy then
	  -- Low energy: switch reactor ON and calculate control rods by
	  -- energy cell level.
	  reactor.setActive(true)
	  rodLvl=calcRodLevel(cellEnergy)
   elseif cellEnergy > highEnergy then
	  -- High energy: switch reactor OFF and set control rod level to 100
	  reactor.setActive(false)
	  rodLvl=100
   elseif cellEnergy > lowEnergy then
	  -- Enough energy: do not change state of reactor. Only recalculate
	  -- control rod level.
	  --
	  -- * If the reactor ist switched off, we will wait until energy
	  --   fall below low energy mark.
	  --
	  -- * If it is turned on, we generate more energy until the
	  --   energy level exeeds the high energy mark.
	  rodLvl=calcRodLevel(cellEnergy)
   end

   reactor.setAllControlRodLevels(rodLvl)

   displayStatus(reactor.getActive(), rodLvl, cellEnergy)

   os.sleep(5) -- Wait for 5s
end

--
-- EOF
--