-- run on a cheep computer to auto_import from a chest

local saved_chest_file = "auto_chest.txt"
local default_chest = 89
local redstone_threshold = 7
local modem = peripheral.find("modem")
local sides = {"top", "bottom", "right", "left", "front", "back"}

local function loadChest()
  if not fs.exists(saved_chest_file) then
    return default_chest
  end

  local file = fs.open(saved_chest_file, "r")
  local data = file.readAll()
  file.close()
  assert(data)
  local res = tonumber(data)
  assert(res)
  return res
end

local chest = loadChest()

local function saveChest()
  local file = fs.open(saved_chest_file, "w")
  file.writeLine(tostring(chest))
  file.close()
end

local function maxRedstone()
  local max = 0
  for _,side in pairs(sides) do
    local res = redstone.getAnalogInput(side)
    if res > max then max = res end
  end
  return max
end

local function checkAndSend()
  local redstone_level = maxRedstone()
  -- print("redstone level = " .. redstone_level)
  if redstone_level >= redstone_threshold then
    print("sending import command...")
    modem.transmit(1, 1, "import " .. chest)
  end
end

local function main(args)
  if #args == 1 then
    local res = tonumber(args[1])
    assert(res)
    chest = res
    saveChest()
  end

  print("running auto_import for chest number " .. chest)
  checkAndSend()
  while true do
    os.pullEvent("redstone")
    checkAndSend()
  end
end

local args = {...}
main(args)