Turtle Branch Miner

local prgm_args = {...};
if(prgm_args[1] == 'usage' or prgm_args[1] == '?' or prgm_args[1] == 'help')then
  print("miner <branches> <blocks between branches> <branch length>");
  return true;
end

local branches = tonumber(prgm_args[1]) or 5;
local branch_interval = (prgm_args[2]~=nil and tonumber(prgm_args[2])+1) or 4;
local branch_length = tonumber(prgm_args[3]) or 10;
local trunk_length = branches*branch_interval;

local cTrunk
local cBranch = 0;
function dig(length)
  local cLength = 0;
  local bDetect, bMoved;
  while(cLength < length)do
    repeat turtle.dig(); os.sleep(0.1); bDetect = turtle.detect(); until bDetect == false;
    bMoved = turtle.forward();
    if(bMoved)then
      cLength = cLength + 1;
      turtle.digUp();
      turtle.digDown();
    end
  end
  while(cLength~=0)do
    bMoved = turtle.back();
    if(bMoved)then
      cLength = cLength - 1;
    end
  end
end

function digTrunk()
  local cLength = 0;
  local bDetect, bMoved;
  while(cLength < trunk_length)do
    repeat turtle.dig(); os.sleep(0.1); bDetect = turtle.detect(); until bDetect == false;
    bMoved = turtle.forward();
    if(bMoved)then
      cLength = cLength + 1;
      turtle.digUp();
      turtle.digDown();
      if(cLength%branch_interval==0)then
        turtle.turnRight();
        dig(branch_length);
        turtle.turnLeft();
        turtle.turnLeft();
        dig(branch_length);
        turtle.turnRight();
      end
    end
  end
  while(cLength~=0)do
    bMoved = turtle.back();
    if(bMoved)then
      cLength = cLength - 1;
    end
  end
end

digTrunk();