3D mining managed modded

-- sourcecode : https://pastebin.com/RvykLz7g
item_blacklist = {"minecraft:cobblestone","chisel:granite","chisel:limestone","chisel:andesite","chisel:diorite","minecraft:dirt", "minecraft:stone", "minecraft:clay_ball", "minecraft:torch", "minecraft:gravel", "minecraft:flint",}

function sleep(s)
  local ntime = os.clock() + s
  repeat until os.clock() > ntime
end

local select_slot = function(id)
  local i = 1
  local data
  while i < 17 do
    turtle.select(i)
    if turtle.getItemCount() > 0 then
      data = turtle.getItemDetail()
      if data.name == id then
        return true
      end
    end
    i = i + 1
  end
  turtle.select(1)
  return false
end

local special_refuel = function()
  if select_slot("minecraft:coal") == true then
    if turtle.getItemCount() >= 5 then
      turtle.refuel(5)
      print("[*] Refuel 5 coal")
    else
      print("[*] Refuel " .. turtle.getItemCount() .. " coal")
      turtle.refuel()
    end
    return true
  end
  return false
end

local is_in_blacklist = function(name)
  local i = 1
  while i <= table.getn(item_blacklist) do
    if name == item_blacklist[i] then
      return true
    end
    i = i + 1
  end
  return false
end

local check_refuel = function()
  if turtle.getFuelLevel() == 0 then
    if not special_refuel() then
      print("[*] Wating for fuel")
      while not special_refuel() do
        sleep(1)
      end
    end
  end
end

local verif_stuff = function()
  local i = 1
  print("[*] Stuff verification")
  check_refuel()
  while i < 17 do
    turtle.select(i)
    if turtle.getItemCount() > 0 then
      data = turtle.getItemDetail()
      if is_in_blacklist(data.name) then
        print("[*] Drop " .. turtle.getItemCount() .. " " .. data.name)
        turtle.drop()
      end
    end
    i = i + 1
  end
end

local mine_x = function(x, total)
  local i = 0
  while i < x do
    check_refuel()
    if (total + i) % 20 == 0 then
      verif_stuff()
    end
    while turtle.forward() == false do
      turtle.dig()
    end
    i = i + 1
  end
  return total + i
end

local mine_y = function(x, y, bool, total)
  local i = 0
  while i < y do
    total = mine_x(x - 1, total)
    if total % 20 == 0 then
      verif_stuff()
    end
    if bool == false and not (i ==  y - 1) then
      --print("turnRight")
      turtle.turnRight()
      total = mine_x(1, total)
      turtle.turnRight()
    elseif not (i ==  y - 1) then
      --print("turnLeft")
      turtle.turnLeft()
      total = mine_x(1, total)
      turtle.turnLeft()
    end
    bool = not bool
    i = i + 1
  end
  return bool, total
end

local mine_z = function(x, y, z)
  local i = 0
  local gobool = false
  local retbool = false
  local total = 0
  verif_stuff()
  while i < z do
    retbool, total = mine_y(x, y, gobool, total)
    if total % 20 == 0 then
      verif_stuff()
    end
    --print("down")
    if not (i == z - 1) then
      turtle.digDown()
      turtle.down()
      turtle.turnRight()
      turtle.turnRight()
    end
    gobool = not retbool
    i = i + 1
  end
  verif_stuff()
end

local arg = { ... }
if not (table.getn(arg) == 3) then
  print("[*] Please use command like this:")
  print("    program x y z")
  print("    program 10 10 5")
else
  mine_z(tonumber(arg[1]), tonumber(arg[2]), tonumber(arg[3]))
end