Excavate Replacement

-- Build Tools
-- dig v1

local args = { ... }

if args[1] == nil or args[2] == nil or args[3] == nil or turtle.getItemCount(1) < 1 or args[1] == "help" then
  print ("Usage: dig [forward length] [right length] [depth]")
  print ("Put an ender chest in the first slot")
  return
end

local tilt = 0
local flength = tonumber(args[1])
local rlength = tonumber(args[2])
local depth = tonumber(args[3])
local blocks = rlength * flength * depth

if turtle.getFuelLevel() < blocks + rlength + flength + depth and args[4] ~= "-f" then
  print ("You do not have enough fuel. This job needs ", fuelreq, " fuel.")
  print ("Add more fuel, or append -f to dig anyway.")
  return
end

function step()
  while not turtle.forward() do
	turtle.dig()
  end
end

function stepUp()
  while not turtle.up() do
	turtle.digUp()
  end
end

function stepDown()
  while not turtle.down() do
	turtle.digDown()
  end
end

function placeUp()
  while not turtle.placeUp() do
	turtle.digUp()
  end
end

function rotateRight()
  turtle.turnRight()
  if vertical then
	stepUp()
  else
	step()
  end
  turtle.turnRight()
end

function rotateLeft()
  turtle.turnLeft()
  if vertical then
	stepUp()
  else
	step()
  end
  turtle.turnLeft()
end

-- Dump inventory into ender chest.
function dump()
  turtle.select(1)
  placeUp()
  for m = 2, 16, 1 do
	turtle.select(m)
	turtle.dropUp()
  end
  turtle.select(1)
  turtle.digUp()
end

-- Dig em up.
for i = 1, depth, 1 do
  for j = 1, rlength, 1 do
	for k = 1, flength, 1 do
	  if turtle.getItemCount(16) > 1 then
		dump()
	  end
	  turtle.digDown()
	  if k < flength then
		step()
	  end
	end
	if j < rlength then
	  if (j + tilt) % 2 ~= 0 then
		rotateRight()
	  else
		rotateLeft()
	  end
	end
  end
  if rlength % 2 == 0 and i % 2 ~= 0 then
	tilt = 1
  else
	tilt = 0
  end
  turtle.turnRight()
  turtle.turnRight()
  stepDown()
end

-- Raise to initial height.
for i = 1, depth, 1 do
  stepUp()
end

-- Return to origin.
if depth % 2 ~= 0 then
  if rlength % 2 == 0 then
	turtle.turnLeft()
	for i = 1, rlength - 1, 1 do
	  step()
	end
  else
	turtle.turnRight()
	for i = 1, rlength - 1, 1 do
	  step()
	end
	turtle.turnLeft()
	for i = 1, flength - 1, 1 do
	  step()
	end
  end
end