Entity Potion Effect Event

src/main/java/ch/njol/skript/classes/data/BukkitEventValues.java

@@ -88,6 +88,7 @@
 import org.bukkit.event.enchantment.PrepareItemEnchantEvent;
 import org.bukkit.event.entity.AreaEffectCloudApplyEvent;
 import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.event.entity.EntityPotionEffectEvent.Cause;
 import org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason;
 import org.bukkit.event.entity.EntityChangeBlockEvent;
 import org.bukkit.event.entity.EntityDamageByEntityEvent;
@@ -96,6 +97,7 @@
 import org.bukkit.event.entity.EntityDeathEvent;
 import org.bukkit.event.entity.EntityEvent;
 import org.bukkit.event.entity.EntityPickupItemEvent;
+import org.bukkit.event.entity.EntityPotionEffectEvent;
 import org.bukkit.event.entity.EntityResurrectEvent;
 import org.bukkit.event.entity.EntityTameEvent;
 import org.bukkit.event.entity.EntityTransformEvent;
@@ -169,6 +171,7 @@
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.inventory.Recipe;
+import org.bukkit.potion.PotionEffect;
 import org.bukkit.potion.PotionEffectType;
 import org.eclipse.jdt.annotation.Nullable;
 
@@ -538,6 +541,33 @@ public DamageCause get(final EntityDeathEvent e) {
 				return ldc == null ? null : ldc.getCause();
 			}
 		}, 0);
+
+		// Entity Potion Effect
+		EventValues.registerEventValue(EntityPotionEffectEvent.class, PotionEffect.class, new Getter<PotionEffect, EntityPotionEffectEvent>() {
+			@Override
+			public PotionEffect get(EntityPotionEffectEvent event) {
+				return event.getOldEffect();
+			}
+		}, EventValues.TIME_PAST);
+		EventValues.registerEventValue(EntityPotionEffectEvent.class, PotionEffect.class, new Getter<PotionEffect, EntityPotionEffectEvent>() {
+			@Override
+			public PotionEffect get(EntityPotionEffectEvent event) {
+				return event.getNewEffect();
+			}
+		}, EventValues.TIME_NOW);
+		EventValues.registerEventValue(EntityPotionEffectEvent.class, PotionEffectType.class, new Getter<PotionEffectType, EntityPotionEffectEvent>() {
+			@Override
+			public PotionEffectType get(EntityPotionEffectEvent event) {
+				return event.getModifiedType();
+			}
+		}, EventValues.TIME_NOW);
+		EventValues.registerEventValue(EntityPotionEffectEvent.class, EntityPotionEffectEvent.Cause.class, new Getter<EntityPotionEffectEvent.Cause, EntityPotionEffectEvent>() {
+			@Override
+			public Cause get(EntityPotionEffectEvent event) {
+				return event.getCause();
+			}
+		}, EventValues.TIME_NOW);
+
 		// ProjectileHitEvent
 		// ProjectileHitEvent#getHitBlock was added in 1.11
 		if (Skript.methodExists(ProjectileHitEvent.class, "getHitBlock"))

src/main/java/ch/njol/skript/events/EvtEntityPotion.java

@@ -0,0 +1,80 @@
+/**
+ *   This file is part of Skript.
+ *
+ *  Skript is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Skript is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Skript.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright Peter Güttinger, SkriptLang team and contributors
+ */
+package ch.njol.skript.events;
+
+import ch.njol.skript.Skript;
+import ch.njol.skript.lang.Expression;
+import ch.njol.skript.lang.Literal;
+import ch.njol.skript.lang.SkriptEvent;
+import ch.njol.skript.lang.SkriptParser;
+import org.bukkit.event.Event;
+import org.bukkit.event.entity.EntityPotionEffectEvent;
+import org.bukkit.potion.PotionEffectType;
+
+import javax.annotation.Nullable;
+
+public class EvtEntityPotion extends SkriptEvent {
+
+	static {
+		Skript.registerEvent("Entity Potion Effect", EvtEntityPotion.class, EntityPotionEffectEvent.class,
+				"entity potion effect [modif[y|ication]] [[of] %potioneffecttypes%]")
+			.description("Called when an entity's potion effect is modified.", "This modification can include adding, removing or changing their potion effect.")
+			.examples(
+				"on entity potion effect modification:",
+					"\t\tbroadcast \"A potion effect was added to %event-entity%!\" ",
+				"",
+				"on entity potion effect modification of night vision:")
+			.since("INSERT VERSION");
+	}
+
+	@SuppressWarnings("unchecked")
+	private Expression<PotionEffectType> potionEffects;
+
+	@Override
+	public boolean init(Literal<?>[] args, int matchedPattern, SkriptParser.ParseResult parseResult) {
+		if (args.length > 0) {
+			potionEffects = (Expression<PotionEffectType>) args[0];
+		}
+		return true;
+	}
+
+
+	@Override
+	public boolean check(Event event) {
+		if (event instanceof EntityPotionEffectEvent) {
+			EntityPotionEffectEvent potionEvent = (EntityPotionEffectEvent) event;
+			if (potionEffects != null && potionEvent.getNewEffect() != null) {
+				PotionEffectType effectType = potionEvent.getNewEffect().getType();
+				for (PotionEffectType potionEffectType : potionEffects.getArray(event)) {
+					if (potionEffectType.equals(effectType)) {
+						return true;
+					}
+				}
+			} else {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	@Override
+	public String toString(@Nullable Event event, boolean debug) {
+		return "on entity potion effect modification";
+	}
+}