MobsTweaksManager.java

package com.hea3ven.hardmodetweaks.mobs;

import java.util.HashSet;

import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.SharedMonsterAttributes;
import net.minecraft.entity.ai.attributes.AttributeModifier;
import net.minecraft.entity.monster.EntityCaveSpider;
import net.minecraft.entity.monster.EntityCreeper;
import net.minecraft.entity.monster.EntitySpider;
import net.minecraft.entity.monster.EntityZombie;
import net.minecraft.init.MobEffects;
import net.minecraft.potion.PotionEffect;
import net.minecraft.util.math.BlockPos;
import net.minecraft.world.EnumSkyBlock;

import net.minecraftforge.event.entity.living.LivingAttackEvent;
import net.minecraftforge.event.entity.living.LivingEvent.LivingUpdateEvent;
import net.minecraftforge.event.entity.living.LivingSpawnEvent;
import net.minecraftforge.fml.common.eventhandler.Event.Result;
import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;

public class MobsTweaksManager {
	public static boolean spidersApplySlowness;
	public static boolean replaceCaveSpiderPoison;
	public static boolean creeperSpawnTweak;
	public static float zombieKnockbackResistance;

	private HashSet<EntityLivingBase> poisonedEntities = new HashSet<>();

	@SubscribeEvent
	public void onLivingAttackEvent(LivingAttackEvent event) {
		if (spidersApplySlowness) {
			if (event.getSource().getDamageType().equals("mob")
					&& event.getSource().getEntity() instanceof EntitySpider) {
				event.getEntityLiving()
						.addPotionEffect(new PotionEffect(MobEffects.SLOWNESS, 200, 1));
			}
		}

		if (replaceCaveSpiderPoison) {
			if (event.getSource().getDamageType().equals("mob")
					&& event.getSource().getEntity() instanceof EntityCaveSpider) {
				poisonedEntities.add(event.getEntityLiving());
			}
		}
	}

	@SubscribeEvent
	public void onLivingUpdateEvent(LivingUpdateEvent event) {
		if (poisonedEntities.contains(event.getEntityLiving())) {
			event.getEntityLiving().removePotionEffect(MobEffects.POISON);
			event.getEntityLiving().addPotionEffect(new PotionEffect(MobEffects.WEAKNESS, 15 * 20));
			poisonedEntities.remove(event.getEntityLiving());
		}
	}

	@SubscribeEvent
	public void onLivingSpawnCheckSpawnEvent(LivingSpawnEvent.CheckSpawn event) {
		if (creeperSpawnTweak) {
			if (event.getEntityLiving() instanceof EntityCreeper) {
				int skyLight = event.getWorld().getLightFor(EnumSkyBlock.SKY,
						new BlockPos(event.getX(), event.getY(), event.getZ()));
				if (skyLight > 8) {
					event.setResult(Result.DENY);
				}
			}
		}
	}

	@SubscribeEvent
	public void onLivingSpawnSpecialSpawnEvent(LivingSpawnEvent.SpecialSpawn event) {
		if (zombieKnockbackResistance > 0) {
			if (event.getEntityLiving() instanceof EntityZombie) {
				EntityZombie zombie = (EntityZombie) event.getEntityLiving();
				zombie
						.getEntityAttribute(SharedMonsterAttributes.KNOCKBACK_RESISTANCE)
						.applyModifier(new AttributeModifier("Base value",
								zombieKnockbackResistance, 0));
			}
		}
	}
}