From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: violetc <58360096+s-yh-china@users.noreply.github.com>
Date: Thu, 2 Jan 2025 22:01:17 +0800
Subject: [PATCH] Fix EntityPortalExitEvent logic


diff --git a/net/minecraft/world/entity/Entity.java b/net/minecraft/world/entity/Entity.java
index a85e8e4df0247ff6b3d4048c9c7a0f1134970c93..91038b21164d3e1bf6406117478454d38b24bb81 100644
--- a/net/minecraft/world/entity/Entity.java
+++ b/net/minecraft/world/entity/Entity.java
@@ -3774,19 +3774,29 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
             }
             if (this.portalProcess != null) { // if in a portal
                 org.bukkit.craftbukkit.entity.CraftEntity bukkitEntity = this.getBukkitEntity();
+                org.bukkit.util.Vector after = org.bukkit.craftbukkit.util.CraftVector.toBukkit(velocity); // Leaves - fix
                 org.bukkit.event.entity.EntityPortalExitEvent event = new org.bukkit.event.entity.EntityPortalExitEvent(
                     bukkitEntity,
                     bukkitEntity.getLocation(), to.clone(),
-                    bukkitEntity.getVelocity(), org.bukkit.craftbukkit.util.CraftVector.toBukkit(velocity)
+                        bukkitEntity.getVelocity(), after // Leaves - fix
                 );
                 event.callEvent();
 
+                // Leaves start - fix
                 // Only change the target if actually needed, since we reset relative flags
-                if (!event.isCancelled() && event.getTo() != null && (!event.getTo().equals(event.getFrom()) || !event.getAfter().equals(event.getBefore()))) { // todo this looks broken
-                    to = event.getTo().clone();
-                    velocity = org.bukkit.craftbukkit.util.CraftVector.toVec3(event.getAfter());
+                if (event.isCancelled() || (!to.equals(event.getTo()) || !after.equals(event.getAfter()))) {
+                    if (!event.isCancelled()) {
+                        if (event.getTo() != null) {
+                            to = event.getTo().clone();
+                        }
+                        velocity = org.bukkit.craftbukkit.util.CraftVector.toVec3(event.getAfter());
+                    } else {
+                        to = event.getFrom().clone();
+                        velocity = Vec3.ZERO;
+                    }
                     teleportTransition = new TeleportTransition(((org.bukkit.craftbukkit.CraftWorld) to.getWorld()).getHandle(), org.bukkit.craftbukkit.util.CraftLocation.toVec3(to), velocity, to.getYaw(), to.getPitch(), teleportTransition.missingRespawnBlock(), teleportTransition.asPassenger(), Set.of(), teleportTransition.postTeleportTransition(), teleportTransition.cause());
                 }
+                // Leaves end - fix
             }
             if (this.isRemoved()) {
                 return null;