From 4f127b2e0ed0fcb80a0fe93b2140df41d2eba9c4 Mon Sep 17 00:00:00 2001
From: TheMode <themode@outlook.fr>
Date: Wed, 2 Jun 2021 21:08:10 +0200
Subject: [PATCH] Separate conditional event from conditional handler

---
 .../java/net/minestom/server/event/EventNode.java   | 13 ++++++++++++-
 .../minestom/server/event/EventNodeConditional.java | 12 ++++++------
 .../net/minestom/server/event/EventNodeImpl.java    |  6 ++++++
 src/test/java/demo/PlayerInit.java                  |  9 ++++++---
 4 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/src/main/java/net/minestom/server/event/EventNode.java b/src/main/java/net/minestom/server/event/EventNode.java
index d7dc8dcbc..67d6358b1 100644
--- a/src/main/java/net/minestom/server/event/EventNode.java
+++ b/src/main/java/net/minestom/server/event/EventNode.java
@@ -4,6 +4,7 @@ import net.minestom.server.event.handler.EventHandler;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
+import java.util.function.BiPredicate;
 import java.util.function.Predicate;
 
 public interface EventNode<T extends Event> {
@@ -17,10 +18,20 @@ public interface EventNode<T extends Event> {
     }
 
     static <E extends Event, H extends EventHandler> EventNodeConditional<E, H> conditional(@NotNull EventFilter<E, H> filter,
-                                                                                            @NotNull Predicate<E> predicate) {
+                                                                                            @NotNull BiPredicate<E, H> predicate) {
         return new EventNodeConditional<>(filter, predicate);
     }
 
+    static <E extends Event, H extends EventHandler> EventNodeConditional<E, H> conditionalEvent(@NotNull EventFilter<E, H> filter,
+                                                                                                 @NotNull Predicate<E> predicate) {
+        return conditional(filter, (e, h) -> predicate.test(e));
+    }
+
+    static <E extends Event, H extends EventHandler> EventNodeConditional<E, H> conditionalHandler(@NotNull EventFilter<E, H> filter,
+                                                                                                   @NotNull Predicate<H> predicate) {
+        return conditional(filter, (e, h) -> predicate.test(h));
+    }
+
     static <E extends Event, H extends EventHandler> EventNodeList<E, H> list(@NotNull EventFilter<E, H> filter) {
         return new EventNodeList<>(filter);
     }
diff --git a/src/main/java/net/minestom/server/event/EventNodeConditional.java b/src/main/java/net/minestom/server/event/EventNodeConditional.java
index 3f8676978..308a0a4a1 100644
--- a/src/main/java/net/minestom/server/event/EventNodeConditional.java
+++ b/src/main/java/net/minestom/server/event/EventNodeConditional.java
@@ -3,27 +3,27 @@ package net.minestom.server.event;
 import net.minestom.server.event.handler.EventHandler;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.function.Predicate;
+import java.util.function.BiPredicate;
 
 public class EventNodeConditional<T extends Event, H extends EventHandler> extends EventNodeImpl<T, H> {
 
-    private volatile Predicate<T> predicate;
+    private volatile BiPredicate<T, H> predicate;
 
-    protected EventNodeConditional(EventFilter<T, H> filter, Predicate<T> predicate) {
+    protected EventNodeConditional(EventFilter<T, H> filter, BiPredicate<T, H> predicate) {
         super(filter);
         this.predicate = predicate;
     }
 
     @Override
     protected boolean condition(@NotNull T event) {
-        return predicate.test(event);
+        return predicate.test(event, filter.getHandler(event));
     }
 
-    public @NotNull Predicate<@NotNull T> getPredicate() {
+    public @NotNull BiPredicate<T, H> getPredicate() {
         return predicate;
     }
 
-    public void setPredicate(@NotNull Predicate<@NotNull T> predicate) {
+    public void setPredicate(@NotNull BiPredicate<T, H> predicate) {
         this.predicate = predicate;
     }
 }
diff --git a/src/main/java/net/minestom/server/event/EventNodeImpl.java b/src/main/java/net/minestom/server/event/EventNodeImpl.java
index 72811af1f..e6b25b983 100644
--- a/src/main/java/net/minestom/server/event/EventNodeImpl.java
+++ b/src/main/java/net/minestom/server/event/EventNodeImpl.java
@@ -22,6 +22,12 @@ class EventNodeImpl<T extends Event, H extends EventHandler> implements EventNod
         this.filter = filter;
     }
 
+    /**
+     * Condition to enter the node.
+     *
+     * @param event the called event
+     * @return true to enter the node, false otherwise
+     */
     protected boolean condition(@NotNull T event) {
         return true;
     }
diff --git a/src/test/java/demo/PlayerInit.java b/src/test/java/demo/PlayerInit.java
index 125858c99..589624ef0 100644
--- a/src/test/java/demo/PlayerInit.java
+++ b/src/test/java/demo/PlayerInit.java
@@ -147,11 +147,14 @@ public class PlayerInit {
         empty.addListener(EventListener.of(PlayerMoveEvent.class, (event) -> {
         }));
 
-        var list = EventNode.list(EventFilter.PLAYER);
-        list.addListener(EventListener.of(PlayerMoveEvent.class, playerMoveEvent -> {
-            System.out.println("move");
+        var conditional = EventNode.conditionalHandler(EventFilter.PLAYER, Player::isCreative);
+        conditional.addListener(EventListener.of(PlayerMoveEvent.class, (event) -> {
+            System.out.println("creative player moved");
         }));
 
+        var list = EventNode.list(EventFilter.PLAYER);
+        list.addListener(EventListener.of(PlayerMoveEvent.class, playerMoveEvent -> System.out.println("move")));
+
         GlobalEventHandler globalEventHandler = MinecraftServer.getGlobalEventHandler();
         globalEventHandler.addEventCallback(EntityAttackEvent.class, event -> {
             final Entity source = event.getEntity();