package net.minecraft.advancements.triggers;

import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.mojang.serialization.Codec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Optional;
import java.util.Set;
import net.minecraft.advancements.predicates.ContextAwarePredicate;
import net.minecraft.advancements.predicates.ItemPredicate;
import net.minecraft.advancements.predicates.MinMaxBounds;
import net.minecraft.advancements.predicates.entity.EntityPredicate;
import net.minecraft.core.HolderGetter;
import net.minecraft.server.level.ServerPlayer;
import net.minecraft.world.entity.Entity;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.ItemInstance;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.Items;
import net.minecraft.world.level.storage.loot.LootContext;
import net.minecraft.world.level.storage.loot.Validatable;
import net.minecraft.world.level.storage.loot.ValidationContextSource;
import org.jspecify.annotations.Nullable;

public class KilledByArrowTrigger extends SimpleCriterionTrigger<KilledByArrowTrigger.TriggerInstance> {
	@Override
	public Codec<KilledByArrowTrigger.TriggerInstance> codec() {
		return KilledByArrowTrigger.TriggerInstance.CODEC;
	}

	public void trigger(final ServerPlayer player, final Collection<Entity> victims, @Nullable final ItemStack firedByWeapon) {
		List<LootContext> victimContexts = Lists.<LootContext>newArrayList();
		Set<EntityType<?>> entityTypes = Sets.<EntityType<?>>newHashSet();

		for (Entity victim : victims) {
			entityTypes.add(victim.getType());
			victimContexts.add(EntityPredicate.createContext(player, victim));
		}

		this.trigger(player, t -> t.matches(victimContexts, entityTypes.size(), firedByWeapon));
	}

	public record TriggerInstance(
		Optional<ContextAwarePredicate> player, List<ContextAwarePredicate> victims, MinMaxBounds.Ints uniqueEntityTypes, Optional<ItemPredicate> firedFromWeapon
	) implements SimpleCriterionTrigger.SimpleInstance {
		public static final Codec<KilledByArrowTrigger.TriggerInstance> CODEC = RecordCodecBuilder.create(
			i -> i.group(
					EntityPredicate.ADVANCEMENT_CODEC.optionalFieldOf("player").forGetter(KilledByArrowTrigger.TriggerInstance::player),
					EntityPredicate.ADVANCEMENT_CODEC.listOf().optionalFieldOf("victims", List.of()).forGetter(KilledByArrowTrigger.TriggerInstance::victims),
					MinMaxBounds.Ints.CODEC.optionalFieldOf("unique_entity_types", MinMaxBounds.Ints.ANY).forGetter(KilledByArrowTrigger.TriggerInstance::uniqueEntityTypes),
					ItemPredicate.CODEC.optionalFieldOf("fired_from_weapon").forGetter(KilledByArrowTrigger.TriggerInstance::firedFromWeapon)
				)
				.apply(i, KilledByArrowTrigger.TriggerInstance::new)
		);

		public static Criterion<KilledByArrowTrigger.TriggerInstance> crossbowKilled(final HolderGetter<Item> items, final EntityPredicate.Builder... victims) {
			return CriteriaTriggers.KILLED_BY_ARROW
				.createCriterion(
					new KilledByArrowTrigger.TriggerInstance(
						Optional.empty(), EntityPredicate.wrap(victims), MinMaxBounds.Ints.ANY, Optional.of(ItemPredicate.Builder.item().of(items, Items.CROSSBOW).build())
					)
				);
		}

		public static Criterion<KilledByArrowTrigger.TriggerInstance> crossbowKilled(final HolderGetter<Item> items, final MinMaxBounds.Ints uniqueEntityTypes) {
			return CriteriaTriggers.KILLED_BY_ARROW
				.createCriterion(
					new KilledByArrowTrigger.TriggerInstance(
						Optional.empty(), List.of(), uniqueEntityTypes, Optional.of(ItemPredicate.Builder.item().of(items, Items.CROSSBOW).build())
					)
				);
		}

		public boolean matches(final Collection<LootContext> victims, final int uniqueEntityTypes, @Nullable final ItemStack firedFromWeapon) {
			if (!this.firedFromWeapon.isPresent() || firedFromWeapon != null && ((ItemPredicate)this.firedFromWeapon.get()).test((ItemInstance)firedFromWeapon)) {
				if (!this.victims.isEmpty()) {
					List<LootContext> victimsCopy = Lists.<LootContext>newArrayList(victims);

					for (ContextAwarePredicate predicate : this.victims) {
						boolean found = false;
						Iterator<LootContext> iterator = victimsCopy.iterator();

						while (iterator.hasNext()) {
							LootContext entity = (LootContext)iterator.next();
							if (predicate.matches(entity)) {
								iterator.remove();
								found = true;
								break;
							}
						}

						if (!found) {
							return false;
						}
					}
				}

				return this.uniqueEntityTypes.matches(uniqueEntityTypes);
			} else {
				return false;
			}
		}

		@Override
		public void validate(final ValidationContextSource validator) {
			SimpleCriterionTrigger.SimpleInstance.super.validate(validator);
			Validatable.validate(validator.entityContext(), "victims", this.victims);
		}
	}
}