turtle_miner.lua

--[[
# Digger: A simple program to dig a 1 x 2 shaft straight
## Author: Brandon Weaver (keystonelemur / baweaver)
--]]

local tArgs = { ... }

if tArgs[1] == 'help' then
  print('Usage:')
  print('')
  return
end

-- Distance to mine
local distance = tArgs[1] or 1

-- Whether or not to set blocks on an imminent fall
local safeBlock = tArgs[2]

-- Whether or not to set torches from slot 2
local torches = tArgs[3]

-- Shorten the turtle name
local t = turtle

function checkFuelLevel()
  return distance - t.getFuelLevel()
end

-- Confirm that we have adequate fuel for the trip
level = checkFuelLevel()
if level > 0 then
  print('Insufficient fuel of '..level..' units, attempting refuel...')
  t.refuel(level)

  newLevel = checkFuelLevel()
  if newLevel > 0 then
    print('Cannot make trip, fuel is short by '..newLevel..' units. Goodbye')
    return
  end
end

print('Mining '..distance..' squares')

-- Set a safety block to keep from a nasty fall
function setSafeBlock()
  if safeBlock then
  	t.select(2)
  	t.placeDown()
  end
end

-- Set a torch for visibility
function setTorch()
  if torches then
  	t.select(3)
  	t.placeDown()
  end
end

-- Clear a forward path
--   Use detection to deal with sand and gravel
function clearForward()
  while t.detect() do t.dig() end
  t.forward()
  t.digUp()
  setSafeBlock()
  setTorch()
end

for i = 0, distance do
  print('Mined '..i..' blocks')
  clearForward()
end