getPipe

-- Revision History
-- 20140804 Initial draft, untested
-- 20140811 update based on initial testing, turtle.compare() doesn't seem to recognize pipes but does recognize dirt/sand
--          so loops will just have to detect that "something" is there that's not whatever surrounds the pipes...i.e.
--          stone, slab, sand...(as those are the three main things I run pipe through), I'm in total pipe recovery mode
--          at this point as tesseracts are now replacing the long pipe runs...
-- Purpose/intro:
-- pipes all over looking unsightly?  the goal of this is to follow a pipe and pick them back up.
-- place pipe to reclaim in slot 1, position turtle directly in front of pipe to reclaim.
-- turtle will start off picking up the pipe, once it doesn't detect a pipe it will attempt to turn to re-acquire the pipe
-- in the event no pipe is to either side, above, or below it, it will stop.  (possibly eventually returning to the start)

-- select object to not reclaim (stone, iron tank wall, etc.)
turtle.select(16)

-- while block in front, grab pipe, move forward
-- position turtle in front of first pipe

while not turtle.compare() do
  if not turtle.forward()
    turtle.dig()
    turtle.forward()
  end

  -- after move, detect either a don't acquire block or nothing then look around
  if turtle.compare() or not turtle.detect() then
    turtle.turnRight()
    -- No pipe to right, check to left.
    if not turtle.compare() then
      turtle.turnLeft()
      turtle.turnLeft()
      -- We know no pipe behind us, so pipe above?  If so, get it.
      if not turtle.compare() then
        if turtle.compareUp() then
          while turtle.compareUp() do
            turtle.digUp()
            turtle.up()
          end
        end
        -- if not, pipe below? If so, get it.
        if turtle.compareDown() then
          while turtle.compareDown() do
            turtle.digDown()
            turtle.down()
          end
        end
        -- in case we moved up or down, attempt to re-acquire pipe 360 degrees.
        if not turtle.compare() then
          turtle.turnRight()
        end
        if not turtle.compare() then
          turtle.turnRight()
        end
        if not turtle.compare() then
          turtle.turnRight()
        end
        if not turtle.compare() then
          turtle.turnRight()
        end
        -- here we should either be facing a pipe, or struck out 4 times, in which case it's time to end.
      end
    end
  end
end
-- FIN