From 84c5b818b8858af70aaeeee49bed25d2f94871c8 Mon Sep 17 00:00:00 2001
From: Luck <git@lucko.me>
Date: Sat, 27 Feb 2021 18:24:39 +0000
Subject: [PATCH] Add cancellable UserUnloadEvent

---
 .../api/event/user/UserUnloadEvent.java       | 50 +++++++++++++++++++
 .../common/event/EventDispatcher.java         |  6 +++
 .../model/manager/user/UserHousekeeper.java   | 10 ++++
 3 files changed, 66 insertions(+)
 create mode 100644 api/src/main/java/net/luckperms/api/event/user/UserUnloadEvent.java

diff --git a/api/src/main/java/net/luckperms/api/event/user/UserUnloadEvent.java b/api/src/main/java/net/luckperms/api/event/user/UserUnloadEvent.java
new file mode 100644
index 000000000..21b2ad5dc
--- /dev/null
+++ b/api/src/main/java/net/luckperms/api/event/user/UserUnloadEvent.java
@@ -0,0 +1,50 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.event.user;
+
+import net.luckperms.api.event.LuckPermsEvent;
+import net.luckperms.api.event.type.Cancellable;
+import net.luckperms.api.event.util.Param;
+import net.luckperms.api.model.user.User;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * Called when a user is about to be unloaded from memory.
+ *
+ * @since 5.3
+ */
+public interface UserUnloadEvent extends LuckPermsEvent, Cancellable {
+
+    /**
+     * Gets the user that is being unloaded
+     *
+     * @return the user that is being unloaded
+     */
+    @Param(0)
+    @NonNull User getUser();
+
+}
diff --git a/common/src/main/java/me/lucko/luckperms/common/event/EventDispatcher.java b/common/src/main/java/me/lucko/luckperms/common/event/EventDispatcher.java
index 4be30ac17..272794236 100644
--- a/common/src/main/java/me/lucko/luckperms/common/event/EventDispatcher.java
+++ b/common/src/main/java/me/lucko/luckperms/common/event/EventDispatcher.java
@@ -88,6 +88,7 @@ import net.luckperms.api.event.user.UserCacheLoadEvent;
 import net.luckperms.api.event.user.UserDataRecalculateEvent;
 import net.luckperms.api.event.user.UserFirstLoginEvent;
 import net.luckperms.api.event.user.UserLoadEvent;
+import net.luckperms.api.event.user.UserUnloadEvent;
 import net.luckperms.api.event.user.track.UserDemoteEvent;
 import net.luckperms.api.event.user.track.UserPromoteEvent;
 import net.luckperms.api.extension.Extension;
@@ -365,6 +366,10 @@ public final class EventDispatcher {
         postAsync(UserLoadEvent.class, user.getApiProxy());
     }
 
+    public boolean dispatchUserUnload(User user) {
+        return postCancellable(UserUnloadEvent.class, false, user.getApiProxy());
+    }
+
     public void dispatchUserDemote(User user, Track track, String from, String to, @Nullable Sender sender) {
         Source source = sender == null ? UnknownSource.INSTANCE : new EntitySourceImpl(new SenderPlatformEntity(sender));
         postAsync(UserDemoteEvent.class, source, track.getApiProxy(), user.getApiProxy(), Optional.ofNullable(from), Optional.ofNullable(to));
@@ -424,6 +429,7 @@ public final class EventDispatcher {
                 UserDataRecalculateEvent.class,
                 UserFirstLoginEvent.class,
                 UserLoadEvent.class,
+                UserUnloadEvent.class,
                 UserDemoteEvent.class,
                 UserPromoteEvent.class
         );
diff --git a/common/src/main/java/me/lucko/luckperms/common/model/manager/user/UserHousekeeper.java b/common/src/main/java/me/lucko/luckperms/common/model/manager/user/UserHousekeeper.java
index 25f72d622..f1ae13665 100644
--- a/common/src/main/java/me/lucko/luckperms/common/model/manager/user/UserHousekeeper.java
+++ b/common/src/main/java/me/lucko/luckperms/common/model/manager/user/UserHousekeeper.java
@@ -26,6 +26,7 @@
 package me.lucko.luckperms.common.model.manager.user;
 
 import me.lucko.luckperms.common.config.ConfigKeys;
+import me.lucko.luckperms.common.model.User;
 import me.lucko.luckperms.common.plugin.LuckPermsPlugin;
 import me.lucko.luckperms.common.util.ExpiringSet;
 
@@ -78,6 +79,15 @@ public class UserHousekeeper implements Runnable {
             return;
         }
 
+        User user = this.userManager.getIfLoaded(uuid);
+        if (user == null) {
+            return;
+        }
+
+        if (this.plugin.getEventDispatcher().dispatchUserUnload(user)) {
+            return;
+        }
+
         // unload them
         if (this.plugin.getConfiguration().get(ConfigKeys.DEBUG_LOGINS)) {
             this.plugin.getLogger().info("User Housekeeper: unloading user data for " + uuid);