Computercraft Extractor Controller 2

--EyeDeck's extractor controller program
f = fs.open("buttonAPI","r")
if f == nil then
  print("Attempting to fetch ButtonAPI...")
  bapi = http.get("http://idek.chir.uno/mc/buttonAPI.lua")
  if (bapi) then
    f = fs.open("buttonAPI","w")
    f.write(bapi.readAll())
    f.close()
    print("...complete, ButtonAPI has been downloaded.")
  else
    print("...failed, ButtonAPI could not be downloaded. Re-run this program to retry, or supply ButtonAPI manually.")
    error("ButtonAPI download failed")
  end
else
  f.close()
end
os.loadAPI("buttonAPI")

ex, cvt, coil, mon = nil, nil, nil, nil

warning = {}
print("Checking peripherals...")
while ex == nil or cvt == nil or coil == nil or mon == nil do
  ex = peripheral.find("Extractor")
  adv1,adv2 = peripheral.find("AdvancedGear")
  mon = peripheral.find("monitor")

  if adv1.getName() == "CVT Unit" then
    cvt = adv1
    coil = adv2
  else
    cvt = adv2
    coil = adv1
  end

  if ex == nil then
    if warning.ex == nil then
      print("Extractor missing!")
      warning.ex = true
    end
     sleep(2)
  elseif cvt == nil then
    if warning.cvt == nil then
      print("CVT missing!")
      warning.cvt = true
    end
    sleep(2)
  elseif coil == nil then
    if warning.coil == nil then
      print("Coil missing!")
      warning.coil = true
    end
    sleep(2)
  elseif mon == nil then
    if warning.mon == nil then
      print("Monitor missing!")
      warning.mon = true
    end
    sleep(2)
  else
    break
  end
end
print("All peripherals present.")

peripherals = 0

--Returns right-most item in extractor, else if empty returns false
function notEmpty()
  item = {}
  for i = 4,1,-1 do
    item = getStackInSlot(ex,i)
    if item ~= nil then
      return item
    end
  end

  return false
end

function getStackInSlot(p,slot)
  sanityCheck()
  item = {}
  item.raw_name, item.dmg, item.qty, item.display_name = p.getSlot(slot-1)

  -- make sure that nil is returned instead of a useless object if there is no item or the script will break in 12 different places
  if item.qty ~= nil then
    return item
  else
    return nil
  end
end

-- A huge hack to prevent a crash when a peripheral is disconnected
function sanityCheck()
  if peripherals < 0 then
    print("A peripheral has been detached!\nWaiting for reattachment...")
    while peripherals < 0 do
      sleep(2)
    end
    print("Resuming.")
  end
end

function writeState(state,val)
  if val == true then val = "1" else val = "0" end

  local file = fs.open(state,"w")
  file.write(val)
  file.close()
end

function readState(state)
  local file = fs.open(state,"r")
  local val

  if file == nil then
    val = false
  else
    val = file.readAll()
    if val == "1" then val = true else val = false end
    file.close()
  end

  return val
end

function updateDisplay(name)
  sanityCheck()
  local old_disp = term.redirect(mon)
  local power_in_hours = math.floor(coil.getEnergy() / 37507786621 * 100)*.01

  if name == nil then -- prevent a crash just in case
    name = "nil"
  end

  term.setCursorPos(2,10)
  term.setTextColor(colors.white)
  -- extra spaces are a hack to clear the last item if necessary ("Ammonium Chloride Solution" is long)
  write("Extracting: ".. name .."                     \n                       ")
  term.setCursorPos(2,12)
  write("Power remaining: ".. power_in_hours .."h         ")
  term.redirect(old_disp)
end

function exLoop()
  while true do
    if isOn then
      print("Beginning extraction...")
      jammed = false

      while isOn do
        local currentItem = notEmpty()

        if currentItem ~= false and jammed == false then
          updateDisplay(currentItem.display_name)
          coil.setSpeed(4096)

          sanityCheck()
          cvt.setRatio(1)
          coil.setTorque(4096)
          sleep(0.75) --sleep(4.2)

          sanityCheck()
          cvt.setRatio(32)
          coil.setTorque(256)
          sleep(0.5) --sleep(2.85)
        else
          if jammed == true then
            updateDisplay("Jammed (check output)")
          else
            updateDisplay("Idle")
          end

          if autoOn then
            sanityCheck()
            coil.setTorque(0)
            sleep(8)
          else
            isOn = false
            buttonAPI.drawButton(mon,2,2,16,7,colors.black,colors.lime,"Start")
          end
        end
      end

    sanityCheck()
    coil.setTorque(0)
    print("Ceasing extraction.")

    else -- isOn == false
      sleep(2)
    end
  end
end

function uiLoop()
  while true do
    sanityCheck()
    event, _, x, y = os.pullEvent("monitor_touch")
    local button_name = buttonAPI.getButton(x,y)
    --print(button_name .. " pressed at " .. x .. "," .. y)

    if button_name == "startstop" then
      if isOn == false then
        buttonAPI.drawButton(mon,2,2,16,7,colors.black,colors.red,"Stop")
        isOn = true
      else
        buttonAPI.drawButton(mon,2,2,16,7,colors.black,colors.lime,"Start")
        isOn = false
      end
      writeState("isOn",isOn)
    elseif button_name == "manualauto" then
      if autoOn == false then
        buttonAPI.drawButton(mon,20,2,16,7,colors.black,colors.yellow,"Automatic")
        autoOn = true
      else
        buttonAPI.drawButton(mon,20,2,16,7,colors.black,colors.blue,"Manual")
        autoOn = false
      end
      writeState("autoOn",autoOn)
    end
  end
end

--[[
  While main function is active, if the item in the output slot remains
  unchanged for ~12 seconds or longer, assume the machine has jammed
  and set a variable to stop the main loop.
--]]
function jamLoop()
  local jamCount = 0
  local lastItem = {}
  local item = nil

  while true do
    if isOn then
      item = getStackInSlot(ex,9)
      if item == nil then
        item = getStackInSlot(ex,8)
      end

      if item == nil then
        lastItem = {}
        jammed = false
        jamCount = 0
      else
        -- comparing the item object directly doesn't work anymore, test count and name instead
        if lastItem.display_name == item.display_name and lastItem.qty == item.qty then
          jamCount = jamCount + 1
        else
          jamCount = 0
        end

        lastItem = item

        if jamCount >= 3 then
          if jammed == false then
            jammed = true
            print("Extractor jammed!")
          end
        else
          jammed = false
        end
      end
    end

    sleep(4)
  end
end

function peripheralLoop()
  while true do
    local event = os.pullEvent()
    if event == "peripheral" then
      peripherals = peripherals + 1
      print("A peripheral has been detached!")
    end
    if event == "peripheral_detach" then
      peripherals = peripherals - 1
      print("A peripheral has been reattached!")
    end
  end
end

mon.setTextScale(0.5)
mon.setBackgroundColor(colors.black)
mon.setTextColor(colors.white)
mon.clear()

coil.setSpeed(4096)
coil.setTorque(0)

isOn = readState("isOn")
autoOn = readState("autoOn")

buttonAPI.drawButton(mon,2,2,16,7,colors.black,isOn and colors.red or colors.lime,isOn and "Stop" or "Start","startstop")
buttonAPI.drawButton(mon,20,2,16,7,colors.black,autoOn and colors.yellow or colors.blue,autoOn and "Automatic" or "Manual","manualauto")

if (notEmpty() ~= false) then
  updateDisplay(notEmpty().display_name)
else
  updateDisplay("Idle")
end

parallel.waitForAll(uiLoop, exLoop, jamLoop, peripheralLoop)