package net.minecraft.world.entity.ai.behavior;

import java.util.List;
import java.util.Optional;
import net.minecraft.core.GlobalPos;
import net.minecraft.core.Holder;
import net.minecraft.world.entity.LivingEntity;
import net.minecraft.world.entity.ai.behavior.declarative.BehaviorBuilder;
import net.minecraft.world.entity.ai.memory.MemoryModuleType;
import net.minecraft.world.entity.ai.village.poi.PoiType;
import net.minecraft.world.entity.npc.villager.Villager;
import net.minecraft.world.entity.npc.villager.VillagerProfession;

public class PoiCompetitorScan {
	public static BehaviorControl<Villager> create() {
		return BehaviorBuilder.create(
			i -> i.group(i.present(MemoryModuleType.JOB_SITE), i.present(MemoryModuleType.NEAREST_LIVING_ENTITIES))
				.apply(
					i,
					(jobSite, nearestEntities) -> (level, body, timestamp) -> {
						GlobalPos pos = i.get(jobSite);
						level.getPoiManager()
							.getType(pos.pos())
							.ifPresent(
								poiType -> i.<List>get(nearestEntities)
									.stream()
									.filter(v -> v instanceof Villager && v != body)
									.map(v -> (Villager)v)
									.filter(LivingEntity::isAlive)
									.filter(nearbyVillager -> competesForSameJobsite(pos, poiType, nearbyVillager))
									.reduce(body, PoiCompetitorScan::selectWinner)
							);
						return true;
					}
				)
		);
	}

	private static Villager selectWinner(final Villager first, final Villager second) {
		Villager winner;
		Villager loser;
		if (first.getVillagerXp() > second.getVillagerXp()) {
			winner = first;
			loser = second;
		} else {
			winner = second;
			loser = first;
		}

		loser.getBrain().eraseMemory(MemoryModuleType.JOB_SITE);
		return winner;
	}

	private static boolean competesForSameJobsite(final GlobalPos pos, final Holder<PoiType> poiType, final Villager nearbyVillager) {
		Optional<GlobalPos> jobSite = nearbyVillager.getBrain().getMemory(MemoryModuleType.JOB_SITE);
		return jobSite.isPresent() && pos.equals(jobSite.get()) && hasMatchingProfession(poiType, nearbyVillager.getVillagerData().profession());
	}

	private static boolean hasMatchingProfession(final Holder<PoiType> poiType, final Holder<VillagerProfession> profession) {
		return profession.value().heldJobSite().test(poiType);
	}
}