for(ItemStack stack : stacks) {
if(stack == null || !(stack.getItem() instanceof IManaItem))
continue;
IManaItem manaItem = (IManaItem) stack.getItem();
if(manaItem.canReceiveManaFromItem(stack, input)) {
Map receivingStacks;
boolean add = false;
if(!receivingPlayers.containsKey(player)) {
add = true;
receivingStacks = new HashMap();