Minecraft - Item Recharging Script Redux

--2013 Ichabod_Clay (Ichabod2032)
--Item charger script for Minecraft.
--This script uses an Interactive Sorter to take an item (ideally from an ender chest)
-- and send it off to charge in a charging station (batbox, MFE, MFSU).
--The way I have it set up is the Sorter scans the chest every so often and, if the
-- proper item is found, takes the item and sends it to a charge station through a
-- Buildcraft pipe. This allows you to fill the chest up with crap, but only send out
-- what needs to be charged!
--The return trip is handled by an Autarchic AND Gate that is set to extract the item
-- from the charge station once it is full. Set 1 setting to energy pulse when an item is
-- in inventory, and the other setting set to energy pulse when charging a fully charged
-- item. Easy Peasy!

--Redux Update: Added the ability to test if an item sent to charge was returned, therefor allowing
-- multiple users to use the same ender chest at the same time. The test is handled by a gate on the
-- return pipe that emits a redstone signal if an item is traversing. The redstone signal is picked up
-- by the computer to let it know that the item is charged.
--If you're confused at all by this explanation (and I know you are, cause I am too), please refer to
-- this picture: http://imgur.com/ejP2juQ . This is my current setup that works without issue (knock on wood).

tArgs = {...};
if #tArgs ~= 1 then
  print("Usage: <name of this program> <side sorter is attached to>");
  return;
end

local sorter = peripheral.wrap(tArgs[1]);

--Redux Update: The programs scans the ender chest using ids from this table.
--Feel free to add more ids for more chargeable items!
local items =
{
  jetpack   = 30209,
  A_jetpack = 30481,
  chest     = 30177,
  pants     = 30176,
  helm      = 30178,
  boots     = 30175,
  Q_Pants   = 30172
};

--Small helper table to make working with cardinal directions easier.
--5/29/13
--East and West values have been swapped from what the interactive sorter's wiki says.
-- Unsure what is causing the values to be incorrect, as the same issues with East and
-- West is present when using Factorization's Routers.
local direction =
{
  down  = 0,
  up    = 1,
  north = 2,
  south = 3,
  west  = 4,
  east  = 5
}

--Helper function to find the actual item ID and
-- meta value from a UUID.
local function getID(uuid)
  id = 0;
  meta = 0;

  if uuid > 32768 then
    id = uuid % 32768;
    meta = (uuid - id) / 32768;
  else
    id = uuid;
    meta = 0;
  end

  return id, meta;
end

--Simple helper function. Returns true, uuid and meta of item if found,
-- false otherwise.
local function findJetpack(direction)
  local inventory = sorter.list(direction);
  for uuid, count in pairs(inventory) do
    local id, meta = getID(uuid);
    for name, itemID in pairs(items) do
      if (id == itemID) and (meta ~= 1) then
        return true, uuid, meta, name;
      end
    end
  end
  return false;
end

--Helper function to find a charged item. Gets the redstone output from a
-- gate on the return pipe coming from the MFE/MFSU
--*Make sure to fill in the required parameter before using!*
-- change EDITME!!! to the side the redstone signal will enter the computer.
-- Make sure to use quotation marks as well
-- eg: rs.getInput("back") or rs.getInput("left")
local function isItemCharged()
  return rs.getInput(EDITME!!!);
end


--*Make sure to fill in the required parameters before using!*
--The sorter's 'extract' function has the following parameters:
-- sorter.extract(from, uuid, to, amount)
--Replace 'from' and 'to' with the correct directions, ideally using
-- the table provided at the top of this script.
-- eg: sorter.extract(direction.north, uuid, direction.down, 1)

--Main loop start! WOO!
while true do
  local jetpackFound, uuid, meta, name = findJetpack(CHANGEME!!!);

  if jetpackFound then
    sorter.extract(CHANGEME!!!, uuid, CHANGEME!!!, 1);
    print("Day: "..os.day().." Time: "..os.time());
    print(name.." sent to charge");
    while true do
      if isItemCharged() then
        print(name.." charged");
        break;
      else
        sleep(0.5);
      end
    end
  end

  sleep(10);
end