Added LevelUnloadEvent

src/pocketmine/Server.php

@@ -840,11 +840,16 @@ class Server{
 	/**
 	 * @param Level $level
 	 * @param bool  $forceUnload
+	 *
+	 * @return bool
 	 */
 	public function unloadLevel(Level $level, $forceUnload = false){
 		if($level->unload($forceUnload) === true and $this->isLevelLoaded($level->getFolderName())){
 			unset($this->levels[$level->getID()]);
+			return true;
 		}
+
+		return false;
 	}
 
 	/**

src/pocketmine/event/level/LevelUnloadEvent.php

@@ -0,0 +1,30 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link   http://www.pocketmine.net/
+ *
+ *
+ */
+
+namespace pocketmine\event\level;
+use pocketmine\event\Cancellable;
+
+/**
+ * Called when a Level is saved
+ */
+class LevelUnloadEvent extends LevelEvent implements Cancellable{
+	public static $handlerList = null;
+}

src/pocketmine/level/Level.php

@@ -31,6 +31,7 @@ use pocketmine\entity\Entity;
 use pocketmine\event\block\BlockBreakEvent;
 use pocketmine\event\block\BlockPlaceEvent;
 use pocketmine\event\level\LevelSaveEvent;
+use pocketmine\event\level\LevelUnloadEvent;
 use pocketmine\event\level\SpawnChangeEvent;
 use pocketmine\event\player\PlayerInteractEvent;
 use pocketmine\item\Item;
@@ -268,9 +269,19 @@ class Level implements ChunkManager, Metadatable{
 	 * @return bool
 	 */
 	public function unload($force = false){
+
+		$ev = new LevelUnloadEvent($this);
+
 		if($this === $this->server->getDefaultLevel() and $force !== true){
+			$ev->setCancelled(true);
+		}
+
+		$this->server->getPluginManager()->callEvent($ev);
+
+		if($ev->isCancelled()){
 			return false;
 		}
+
 		$this->server->getLogger()->info("Unloading level \"" . $this->getName() . "\"");
 		$this->nextSave = PHP_INT_MAX;
 		$defaultLevel = $this->server->getDefaultLevel();