public void callRedstoneEvent(BlockRedstoneEvent event) {
    boolean on = event.getNewCurrent() > event.getOldCurrent();

    for (BlockFace direction :
        Arrays.asList(
            BlockFace.NORTH, BlockFace.EAST, BlockFace.SOUTH, BlockFace.WEST, BlockFace.UP)) {
      Block block = event.getBlock().getRelative(direction);
      if (SignUtil.isSign(block)) {
        Sign sign = SignUtil.getSign(block);
        List<SignMechanic> list =
            redstoneSignMechanicMap.get(SignUtil.getMechanicsIdentifier(sign));
        if (list == null) {
          list = new ArrayList<SignMechanic>();
        }
        if (redstoneSignMechanicMap.containsKey(null)) {
          list.addAll(redstoneSignMechanicMap.get(null));
        }
        for (SignMechanic mechanic : list) {
          try {
            BlockBagHandler bag = null;
            BlockMap map = null;
            if (mechanic.hasBlockMapper()) {
              map = mechanic.mapBlocks(sign);
            }
            if (mechanic.hasBlockBag()) {
              bag = BlockBagHandler.locate(sign);
            }
            SignMechanicEventData data = new SignMechanicEventData(map, bag);
            if (on) {
              mechanic.onSignPowerOn(data);
            } else {
              mechanic.onSignPowerOff(data);
            }
          } catch (BlockMapException e) {
            BetterMechanics.log(e.getMessage());
          } catch (BlockBagException e) {
            BetterMechanics.log(e.getMessage());
          }
        }
      } else {
        List<BlockMechanic> list = redstoneBlockMechanicMap.get(block.getType());
        if (list == null) {
          list = new ArrayList<BlockMechanic>();
        }
        if (blockMechanicMap.containsKey(null)) {
          list.addAll(blockMechanicMap.get(null));
        }
        for (BlockMechanic mechanic : list) {
          if (on) {
            mechanic.onBlockPowerOn(event.getBlock());
          } else {
            mechanic.onBlockPowerOff(event.getBlock());
          }
        }
      }
    }
  }
  public void addMechanic(IMechanic mechanic) {
    // TODO: check if this list works as it's supposed to (with passing a reference)
    if (mechanic instanceof SignMechanic) {
      SignMechanic signMechanic = (SignMechanic) mechanic;
      if (signMechanic.isTriggeredByRedstone()) {
        for (String identifier : signMechanic.getIdentifier()) {
          ArrayList<SignMechanic> list = redstoneSignMechanicMap.get(identifier);
          if (list == null) {
            list = new ArrayList<SignMechanic>();
            list.add(signMechanic);
            redstoneSignMechanicMap.put(identifier, list);
          } else {
            list.add(signMechanic);
            redstoneSignMechanicMap.put(identifier, list);
          }
        }
      } else {
        for (String identifier : signMechanic.getIdentifier()) {
          ArrayList<SignMechanic> list = signMechanicMap.get(identifier);
          if (list == null) {
            list = new ArrayList<SignMechanic>();
            list.add(signMechanic);
            signMechanicMap.put(identifier, list);
          } else {
            list.add(signMechanic);
          }
        }
      }
    } else if (mechanic instanceof BlockMechanic) {
      BlockMechanic blockMechanic = (BlockMechanic) mechanic;
      if (blockMechanic.isTriggeredByRedstone()) {
        for (Material target : blockMechanic.getMechanicTarget()) {
          ArrayList<BlockMechanic> list = redstoneBlockMechanicMap.get(target);
          if (list == null) {
            list = new ArrayList<BlockMechanic>();
            list.add(blockMechanic);
            redstoneBlockMechanicMap.put(target, list);
          } else {
            list.add(blockMechanic);
            redstoneBlockMechanicMap.put(target, list);
          }
        }
      } else {
        for (Material target : blockMechanic.getMechanicTarget()) {
          ArrayList<BlockMechanic> list = blockMechanicMap.get(target);
          if (list == null) {
            list = new ArrayList<BlockMechanic>();
            list.add(blockMechanic);
            blockMechanicMap.put(target, list);
          } else {
            list.add(blockMechanic);
          }
        }
      }
    }

    if (mechanic instanceof ICommandableMechanic) {
      ICommandableMechanic commandableMechanic = (ICommandableMechanic) mechanic;
      if (commandableMechanicMap.containsKey(commandableMechanic.getName())) {
        BetterMechanics.log(
            "Mechanic: "
                + commandableMechanic.getName()
                + " tried to register a command that has already been registered!",
            Level.SEVERE);
      } else {
        commandableMechanicMap.put(commandableMechanic.getName(), commandableMechanic);
      }
    }
  }
 public void callPlayerInteractEvent(PlayerInteractEvent event) {
   if (SignUtil.isSign(event.getClickedBlock())) {
     Sign sign = SignUtil.getSign(event.getClickedBlock());
     String id = SignUtil.getMechanicsIdentifier(sign);
     List<SignMechanic> mechanicsList = signMechanicMap.get(id);
     if (mechanicsList == null) {
       mechanicsList = new ArrayList<SignMechanic>();
     }
     if (signMechanicMap.containsKey(null)) {
       mechanicsList.addAll(signMechanicMap.get(null));
     }
     if (redstoneSignMechanicMap.containsKey(id)) {
       mechanicsList.addAll(redstoneSignMechanicMap.get(id));
     }
     if (redstoneSignMechanicMap.containsKey(null)) {
       mechanicsList.addAll(redstoneSignMechanicMap.get(null));
     }
     for (SignMechanic mechanic : mechanicsList) {
       try {
         BlockBagHandler bag = null;
         BlockMap map = null;
         if (mechanic.hasBlockMapper()) {
           map = mechanic.mapBlocks(sign);
         }
         if (mechanic.hasBlockBag()) {
           bag = BlockBagHandler.locate(sign);
         }
         SignMechanicEventData data = new SignMechanicEventData(map, bag);
         if (event.getAction() == Action.LEFT_CLICK_BLOCK) {
           mechanic.onPlayerLeftClickSign(event.getPlayer(), data);
         } else if (event.getAction() == Action.RIGHT_CLICK_BLOCK) {
           mechanic.onPlayerRightClickSign(event.getPlayer(), data);
         }
       } catch (BlockMapException e) {
         event.getPlayer().sendMessage(ChatColor.DARK_RED + e.getMessage());
         BetterMechanics.log(e.getMessage());
       } catch (BlockBagException e) {
         event.getPlayer().sendMessage(ChatColor.DARK_RED + e.getMessage());
         BetterMechanics.log(e.getMessage());
       }
     }
   } else {
     List<BlockMechanic> mechanicsList = blockMechanicMap.get(event.getClickedBlock().getType());
     if (mechanicsList == null) {
       mechanicsList = new ArrayList<BlockMechanic>();
     }
     if (blockMechanicMap.containsKey(null)) {
       mechanicsList.addAll(blockMechanicMap.get(null));
     }
     if (redstoneBlockMechanicMap.containsKey(event.getClickedBlock().getType())) {
       mechanicsList.addAll(redstoneBlockMechanicMap.get(event.getClickedBlock().getType()));
     }
     if (redstoneBlockMechanicMap.containsKey(null)) {
       mechanicsList.addAll(redstoneBlockMechanicMap.get(null));
     }
     for (BlockMechanic mechanic : mechanicsList) {
       if (mechanic.getMechanicActivator() == null
           || mechanic
               .getMechanicActivator()
               .contains(event.getPlayer().getItemInHand().getType())) {
         if (event.getAction() == Action.LEFT_CLICK_BLOCK) {
           mechanic.onBlockLeftClick(event.getPlayer(), event.getClickedBlock());
         } else if (event.getAction() == Action.RIGHT_CLICK_BLOCK) {
           mechanic.onBlockRightClick(event.getPlayer(), event.getClickedBlock());
         }
       }
     }
   }
 }