ComputerCraft Tutorial: woodcutter0_1

local S_WOOD = 1
local S_CCOAL = 16
local S_SAPLING = 2
local S_DIRT = 15
local SLEEP_TIME = 120

local qty_wood = 0
local count_checked = 0

function waitForEnoughItems(itemName, n, slot)
  turtle.select(slot)
  while turtle.getItemCount(slot) < n do
    if itemName then print(string.format("Insert %s into slot %d",itemName,slot)) end
    os.sleep(0.5)
    os.pullEvent("turtle_inventory")
  end
end

function waitForEnoughFuel(minLevel, slot)
  local qty = turtle.getFuelLevel()
  local refuel = function()
    if qty > minLevel then return qty end
    turtle.select(slot)
    turtle.refuel()
    qty = turtle.getFuelLevel()
    print("fuel: ",qty)
    return qty
  end

  while refuel() < minLevel do
    print(string.format("Insert fuel-items into slot %d: %d/%d", slot, qty, minLevel))
    os.sleep(1)
    os.pullEvent("turtle_inventory")
  end
end


function isWood(direction)
  turtle.select(S_WOOD)
  if direction == "top" then
    return turtle.compareUp()
  else
    return turtle.compare()
  end
end

function cutWoods()
  turtle.select(S_WOOD)
  turtle.dig()
  turtle.forward()

  while turtle.detectUp() do
    turtle.digUp()
    turtle.up()
  end
end

function cutLeaves()
  turtle.select(S_SAPLING)
  while not turtle.detectDown() do
    for i=1,4 do
      turtle.dig()
      turtle.turnRight()
    end
    turtle.down()
  end
end

function placeItem(slot, direction)
  turtle.select(slot)
  if direction == "down" then
    turtle.placeDown()
  else
    turtle.place()
  end
end

function getSapling()
  turtle.select(S_DIRT)
  turtle.digDown()
  turtle.down()

  for i=1,4 do
    turtle.select(S_SAPLING)
    turtle.suck()
    turtle.turnRight()
  end

  turtle.up()
  placeItem(S_DIRT, "down")
  turtle.back()
  placeItem(S_SAPLING)
end


function dropItem(slot, nLeaves)
  turtle.select(slot)
  local n = turtle.getItemCount()
  if n > nLeaves then
    if slot == S_WOOD then
      qty_wood = qty_wood + (n-nLeaves)
      print(qty_wood)
    end
    return turtle.drop(n-nLeaves)
  else
    return false, "No items to drop"
  end
end

function fillItemSlot(slot, direction)
  turtle.select(slot)
  local n = turtle.getItemSpace()
  if direction == "down" then
    return turtle.suckDown(n)
  else
    return turtle.suck(n)
  end
end

function makeCoal()
  turtle.back()
  turtle.back()
  turtle.back()
  turtle.turnRight()
  turtle.turnRight()

  fillItemSlot(S_CCOAL, "down")
  dropItem(S_CCOAL, 2)
  if turtle.getFuelLevel() < 80 then
    turtle.select(S_CCOAL)
    assert(turtle.refuel(1), "FuelLevel is low.")
  end

  turtle.up()
  turtle.up()
  assert(dropItem(S_WOOD, 2), "The chest for woods is full.")

  turtle.down()
  turtle.down()
  turtle.turnLeft()
  dropItem(S_WOOD, 2)
  dropItem(S_SAPLING, 32)

  turtle.turnLeft()
  turtle.forward()
  turtle.forward()
  turtle.forward()
end




-- main
waitForEnoughItems("BirchSapling", 2, S_SAPLING)
waitForEnoughItems("BirchWood", 1, S_WOOD)
waitForEnoughItems("Dirt", 2, S_DIRT)
waitForEnoughFuel(80, S_CCOAL)

while true do
  local isWood = isWood()
  if isWood or count_checked > 1 then
    print("Start cutting.")
    count_checked = 0
    cutWoods()
    cutLeaves()
    getSapling()

    if isWood then makeCoal() end
  else
    count_checked = count_checked+1
    print("It isn't wood.")
  end
  turtle.select(S_SAPLING)
  turtle.suckUp()
  turtle.suckDown()
  turtle.suck()
  os.sleep(SLEEP_TIME)
end