Class BrewingTask

src/main/java/com/volmit/adapt/api/potion/BrewingTask.java:14–103

import org.bukkit.scheduler.BukkitRunnable;

public class BrewingTask extends BukkitRunnable {

    private static final int DEFAULT_BREW_TIME = 400;

    @Getter
    private final BrewingRecipe recipe;

    private final Location location;
    private int brewTime;

    public BrewingTask(BrewingRecipe recipe, Location loc) {
        this.recipe = recipe;
        this.location = loc;
        this.brewTime = recipe.getBrewingTime();

        BrewingStand block = (BrewingStand) loc.getBlock().getState();
        if (block.getFuelLevel() > recipe.getFuelCost()) {
            block.setFuelLevel(block.getFuelLevel() - recipe.getFuelCost());
        } else {
            int rest = recipe.getFuelCost() - block.getFuelLevel();
            block.getInventory().setIngredient(decrease(block.getInventory().getFuel(), 1 + rest / 20));
            block.setFuelLevel(20 - rest % 20);
        }

        block.setBrewingTime(DEFAULT_BREW_TIME);
        block.update(true);

        runTaskTimer(Adapt.instance, 0L, 1L);
    }

    public static ItemStack decrease(ItemStack source, int amount) {
        if (source.getAmount() > amount) {
            source.setAmount(source.getAmount() - amount);
            return source;
        } else {
            return new ItemStack(Material.AIR);
        }
    }

    public static boolean isValid(BrewingRecipe recipe, Location loc) {
        BrewingStand block = (BrewingStand) loc.getBlock().getState();
        BrewerInventory inv = block.getInventory();
        if (inv.getIngredient() == null || recipe.getIngredient() != inv.getIngredient().getType()) {
            return false;
        }

        int totalFuel = (inv.getFuel() != null && inv.getFuel().getType() != Material.AIR ? inv.getFuel().getAmount() * 20 : 0) + block.getFuelLevel();
        if (totalFuel < recipe.getFuelCost()) {
            return false;
        }

        for (int i = 0; i < 3; i++) {
            if (recipe.getBasePotion().isSimilar(inv.getItem(i))) {
                return true;
            }
        }

        return false;