Comparable<ItemStack>

ItemStackComparable.java

@NotNull
    private Comparator<ItemStack> itemStackComparator() {
        return (o1, o2) -> {
            //Sort first by their order in storableItems (left to right)
            ItemStack o1BaseItem = getBaseItem(o1);
            ItemStack o2BaseItem = getBaseItem(o2);

            List<ItemStack> storablesList = new ArrayList<>(storableItems.keySet());
            int compare = Integer.compare(storablesList.indexOf(o1BaseItem), storablesList.indexOf(o2BaseItem));
            if (compare != 0) return compare;

            if (o1BaseItem.isSimilar(o2BaseItem)) {
                //If the two base items are the same...

                if (o1.getType() == Material.ENCHANTED_BOOK) {
                    Map.Entry<Enchantment, Integer> enchantment = getFirstEnchantment(o1, true);
                    Map.Entry<Enchantment, Integer> enchantment2 = getFirstEnchantment(o2, true);
                    if (enchantment != null && enchantment2 != null) {
                        Enchantment key = enchantment.getKey();
                        Enchantment key2 = enchantment2.getKey();

                        if (key.getKey().equals(key2.getKey())) {
                            //If they share the same first enchantment, compare the enchant level
                            compare = Integer.compare(enchantment2.getValue(), enchantment.getValue());
                            if (compare != 0) return compare;
                        } else {
                            //Compare just based on key name? Which I suppose would be alphabetical
                            compare = key.getKey().getKey().compareTo(key2.getKey().getKey());
                            if (compare != 0) return compare;
                        }
                    }
                } else if (o1.getType() == Material.FIREWORK_ROCKET) {
                    FireworkMeta fireworkMeta = (FireworkMeta) o1.getItemMeta();
                    FireworkMeta fireworkMeta2 = (FireworkMeta) o2.getItemMeta();
                    compare = Integer.compare(fireworkMeta2.getPower(), fireworkMeta.getPower());
                    if (compare != 0) return compare;
                }

                //Compare by durability
                if (o1.getItemMeta() instanceof Damageable) {
                    Damageable damageable = (Damageable) o1.getItemMeta();
                    if (damageable.getDamage() > 0) {
                        compare = Integer.compare(damageable.getDamage(), ((Damageable) o2.getItemMeta()).getDamage());
                        if (compare != 0) return compare;
                    }
                }
            }

            compare = Integer.compare(o1.hashCode(), o2.hashCode());
            if (compare != 0) return compare;

            //At this point, these are identical items based on item hashcode. Player heads are a good example of
            //things like this. Does it have a display name?
            String displayName = getDisplayName(o1);
            String displayName2 = getDisplayName(o2);
            if (displayName != null && displayName2 != null) {
                compare = displayName.compareTo(displayName2);
                if (compare != 0) return compare;
            }

            //Ok how's about comparing itemstack size.
            compare = Integer.compare(o2.getAmount(), o1.getAmount());
            if (compare != 0) return compare;

            TheArtifact.log.warning(this.toString() + " Comparison between " + o1 + " and " + o2 + " is 0!");
            return 1;
        };
    }