NetherStar

-- TO INSTALL JUST EXECUTE: pastebin get GscK4883 netherstar.lua

local component = require("component")
local robot = require("robot")
local shell = require("shell")
local sides = require("sides")
local chests = component.inventory_controller
local sandChestPlace = sides.bottom
local scullChestPlace = sides.up
local sandSlot = 1
local skullSlot = 2


local function getItems()
--  for i=1,tonumber(chest.getInventorySize(sides.bottom)) do
--    if chest.getStackInSlot(chestPlace, i) then
--      if chest.getStackInSlot(chestPlace, i).label == "Soul Sand" then
--        print("suck Soul Sand from chest")
--        chest.suckFromSlot(chestPlace, i)
--        sandSlot = i
--      elseif chest.getStackInSlot(chestPlace, i).label == "Wither Skeleton Skull" then
--        print("suck Wither Skelleton Skull from chest")
--        chest.suckFromSlot(chestPlace, i)
--        skullSlot = i
--      end
--    end
--  end
  if tonumber(chests.getSlotStackSize(sandChestPlace, 1)) >= 64 and tonumber(chests.getSlotStackSize(scullChestPlace, 1)) >= 48 then
    robot.select(sandSlot)
    chests.suckFromSlot(sandChestPlace, 1, 64)

    robot.select(skullSlot)
    chests.suckFromSlot(scullChestPlace, 1, 48)
    return true
  else
    return false
  end
end


local function moveToBuild()
  for i=1,3 do robot.back() end
  robot.turnRight()
  for i=1,2 do robot.forward() end
  for i=1,2 do robot.down() end
end

local function buildWither()
  robot.select(sandSlot)
  robot.place()
  robot.up()
  robot.place()
  robot.turnRight()
  robot.forward()
  robot.turnLeft()
  robot.place()
  robot.turnLeft()
  for i=1,2 do robot.forward() end
  robot.turnRight()
  robot.place()
  robot.up()
  robot.select(skullSlot)
  robot.place()
  robot.turnRight()
  for i=1,2 do robot.forward() end
  robot.turnLeft()
  robot.place()
  robot.turnRight()
  robot.back()
  robot.turnLeft()
  robot.place()
end

local function moveToChest()
  for i=1,2 do robot.back() end
  robot.turnLeft()
  for i=1,3 do robot.forward() end
end


-- RUNTIME STARTS HERE

while true do
  if getItems() == true then
    for j=1, 16 do
      moveToBuild()
      buildWither()
      moveToChest()
      os.sleep(15)
    end
  else
    os.sleep(60)
  end
end