Add simple ItemPickupEvent

Plugin/src/main/java/dev/rosewood/rosestacker/event/ItemPickupEvent.java

@@ -0,0 +1,66 @@
+package dev.rosewood.rosestacker.event;
+
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.entity.EntityEvent;
+import dev.rosewood.rosestacker.stack.StackedItem;
+import org.jetbrains.annotations.NotNull;
+
+public class ItemPickupEvent extends EntityEvent implements Cancellable {
+
+    private static final HandlerList HANDLERS = new HandlerList();
+
+    private final StackedItem stackedItem;
+    private boolean cancelled;
+
+    /**
+     * @param entity The entity picking up item
+     * @param stackedItem The StackedItem being picking up from stacked dropped items
+     */
+    public ItemPickupEvent(@NotNull final LivingEntity entity, @NotNull final StackedItem stackedItem) {
+        super(entity);
+        this.stackedItem = stackedItem;
+    }
+
+    /**
+     * Gets the entity picking up items.
+     *
+     * @return the entity try to pick up item
+     */
+    @NotNull
+    @Override
+    public LivingEntity getEntity() {
+        return (LivingEntity) entity;
+    }
+
+    /**
+     * Gets the StackedItem being picking up.
+     *
+     * @return the StackedItem being picking up
+     */
+    @NotNull
+    public StackedItem getStackedItem() {
+        return this.stackedItem;
+    }
+
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLERS;
+    }
+
+    public static HandlerList getHandlerList() {
+        return HANDLERS;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancelled) {
+        this.cancelled = cancelled;
+    }
+
+}

Plugin/src/main/java/dev/rosewood/rosestacker/listener/ItemListener.java

@@ -1,6 +1,7 @@
 package dev.rosewood.rosestacker.listener;
 
 import dev.rosewood.rosegarden.RosePlugin;
+import dev.rosewood.rosestacker.event.ItemPickupEvent;
 import dev.rosewood.rosestacker.manager.ConfigurationManager;
 import dev.rosewood.rosestacker.manager.StackManager;
 import dev.rosewood.rosestacker.manager.StackSettingManager;
@@ -10,11 +11,14 @@
 import dev.rosewood.rosestacker.utils.StackerUtils;
 import java.util.ArrayList;
 import java.util.List;
+
+import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.Sound;
 import org.bukkit.block.Container;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
+import org.bukkit.entity.LivingEntity;
 import org.bukkit.entity.Player;
 import org.bukkit.entity.Villager;
 import org.bukkit.event.EventHandler;
@@ -79,6 +83,14 @@ public void onItemPickup(EntityPickupItemEvent event) {
         if (stackedItem == null)
             return;
 
+        // Fire the event to allow other plugins to manipulate the items before we pick up items from stacked item
+        ItemPickupEvent pickupEvent = new ItemPickupEvent(event.getEntity(), stackedItem);
+        Bukkit.getPluginManager().callEvent(pickupEvent);
+        if (pickupEvent.isCancelled()) {
+            event.setCancelled(true);
+            return;
+        }
+
         Inventory inventory;
         if (event.getEntity() instanceof Player player) {
             if (StackerUtils.isVanished(player)) {