Burrow

local tArgs = {...}

toWid = tonumber(tArgs[1])
toHei = tonumber(tArgs[2])
toLen = tonumber(tArgs[3])

print("digging "..toLen.." layers of "..toWid.."*"..toHei)

function layer(wid, hei)
 for i=1, wid do
  for i=1, hei do
   turtle.dig()
   if i < hei then
    turtle.digDown()
   end
   turtle.down()
  end
  for i=1, hei-1 do
   turtle.up()
  end
  if i < wid then
   turtle.turnRight()
   turtle.dig()
   turtle.forward()
   turtle.turnLeft()
  end
 end
end

for i=1, toLen-1 do
 layer(toWid, toHei)
 if ((toLen-1)-i) > 0 then
  print("Layer complete. "..(toLen-1)-i.." remain.")
 else
  print("Done.")
 end
 turtle.turnLeft()
 for i=1, toWid do
  turtle.forward()
 end
 turtle.turnRight()
 turtle.forward()
end