mine3

-- API for more complex mining functions
os.loadAPI("theinsekt/turtle2")
os.loadAPI("theinsekt/mine2")

function tunnel3(length)
  local i=0
  while i<length do
    if mine2.digLoop("f",1)~=1 then
      return i
    end
    mine2.digLoop("u",0)
    mine2.digLoop("d",0)
    -- removes some extra gravel
    mine2.digLoop("u",0)
    i=i+1
  end
  return i
end

-- digs a 3 height tunnel, shaped
-- like a horizontal U
function horzU(length, width)
   local length2=tunnel3(length)
   if width>0 then
     mine2.turn("r",1)
     tunnel3(width)
     mine2.turn("r",1)
   else
     mine2.turn("l",1)
     tunnel3(-width)
     mine2.turn("l",1)
   end
   local length3=tunnel3(length2)
   -- returns the distance from start
   -- in the length direction
   return length2-length3
end

-- Digs an u, and then a reversed u,
-- this creates a zigzag pattern.
-- With width=3 and length>40
-- a efficient strip mining pattern is
-- created.
function stripMine(length, width, iters)
  local i=0
  while i<iters do
    if horzU(length,width)~=0 then
      return i
    end
    horzU(0,-width)
    i=i+1
  end
  return i
end

-- direction can only be u or d
function stairs(dir, length)
  if not (dir=="u" or dir=="d") then
    print("Error: direction must be u or d")
    return 0
  end

  local i=0
  while i<length do
    mine2.digLoop("u",0)
    mine2.digLoop("d",0)
    if mine2.digLoop("f",1)==0 then
      return i
    end --if
    mine2.digLoop("u",0)
    mine2.digLoop("d",0)
    if mine2.digLoop(dir,1)==0 then
       return i
    end --if
    i=i+1
  end
end

-- test
--print(stairs("d",3))