Make placeholder cache updates safe on the user-storage worker

VotingPlugin/src/main/java/com/bencodez/votingplugin/VotingPluginMain.java

@@ -39,6 +39,7 @@
 import com.bencodez.advancedcore.api.item.ItemBuilder;
 import com.bencodez.advancedcore.api.javascript.JavascriptPlaceholderRequest;
 import com.bencodez.advancedcore.api.messages.PlaceholderUtils;
+import com.bencodez.advancedcore.api.player.UuidLookup;
 import com.bencodez.advancedcore.api.rewards.DirectlyDefinedReward;
 import com.bencodez.advancedcore.api.rewards.Reward;
 import com.bencodez.advancedcore.api.rewards.RewardEditData;
@@ -96,6 +97,7 @@
 import com.bencodez.votingplugin.listeners.VotingPluginUpdateEvent;
 import com.bencodez.votingplugin.placeholders.MVdWPlaceholders;
 import com.bencodez.votingplugin.placeholders.PlaceHolders;
+import com.bencodez.votingplugin.placeholders.PlaceholderPlayerPresence;
 import com.bencodez.votingplugin.placeholders.VotingPluginExpansion;
 import com.bencodez.votingplugin.presets.VoteSitePresetSetupHandler;
 import com.bencodez.votingplugin.proxy.control.HostedControlManager;
@@ -231,6 +233,9 @@ public File getLoadedPluginJarFile() {
 	@Getter
 	private PlaceHolders placeholders;
 
+	@Getter
+	private final PlaceholderPlayerPresence placeholderPlayerPresence = new PlaceholderPlayerPresence();
+
 	@Getter
 	private VoteTester voteTester;
 
@@ -650,6 +655,7 @@ public void onPostLoad() {
 		registerCommands();
 		checkVotifier();
 		registerEvents();
+		refreshPlaceholderPlayerPresence();
 
 		loadVoteBroadcast();
 
@@ -1791,6 +1797,7 @@ public void onFinish() {
 
 	@Override
 	public void onUnLoad() {
+		placeholderPlayerPresence.clear();
 		stopBackendHostedControlLifecycle();
 		stopBackendControlConnectorLifecycle();
 		if (getBackendProxyHandler() != null) {
@@ -1929,6 +1936,23 @@ public void reloadAll() {
 		reloadPlugin(true, true);
 	}
 
+	/** Captures Bukkit presence while the lifecycle caller owns platform access. */
+	public void refreshPlaceholderPlayerPresence() {
+		boolean onlineMode = getOptions().isOnlineMode();
+		placeholderPlayerPresence.replace(Bukkit::getOnlinePlayers,
+				player -> placeholderStorageUuid(player, onlineMode));
+	}
+
+	static UUID placeholderStorageUuid(Player player, boolean onlineMode) {
+		if (onlineMode) return player.getUniqueId();
+		String cachedUuid = UuidLookup.getInstance().getCachedUUID(player.getName());
+		try {
+			return UUID.fromString(cachedUuid);
+		} catch (IllegalArgumentException | NullPointerException ignored) {
+			return player.getUniqueId();
+		}
+	}
+
 	/** Reloads configuration applied by Control before its result is acknowledged. */
 	public void reloadFromControl() {
 		reloadPlugin(false, false);

VotingPlugin/src/main/java/com/bencodez/votingplugin/listeners/PlayerJoinEvent.java

@@ -1,4 +1,6 @@
-package com.bencodez.votingplugin.listeners;
+package com.bencodez.votingplugin.listeners;
+
+import java.util.UUID;
 
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
@@ -8,9 +10,10 @@
 
 import com.bencodez.advancedcore.api.player.UuidLookup;
 import com.bencodez.advancedcore.api.user.UserDataFetchMode;
-import com.bencodez.advancedcore.listeners.AdvancedCoreLoginEvent;
-import com.bencodez.votingplugin.VotingPluginMain;
-import com.bencodez.votingplugin.user.VotingPluginUser;
+import com.bencodez.advancedcore.listeners.AdvancedCoreLoginEvent;
+import com.bencodez.votingplugin.VotingPluginMain;
+import com.bencodez.votingplugin.placeholders.PlaceHolders;
+import com.bencodez.votingplugin.user.VotingPluginUser;
 
 public class PlayerJoinEvent implements Listener {
 
@@ -26,18 +29,38 @@ public PlayerJoinEvent(VotingPluginMain plugin) {
 		this.plugin = plugin;
 	}
 
-	private static boolean isBlank(String s) {
-		return s == null || s.trim().isEmpty() || "null".equalsIgnoreCase(s.trim());
-	}
+	/** Capture the entity owner before asynchronous user notifications can need it. */
+	@EventHandler(priority = EventPriority.LOWEST)
+	public void onPlayerJoin(org.bukkit.event.player.PlayerJoinEvent event) {
+		if (event == null || event.getPlayer() == null) return;
+		Player player = event.getPlayer();
+		plugin.getPlaceholderPlayerPresence().playerOnline(placeholderUuid(player), player);
+	}
+
+	private UUID placeholderUuid(Player player) {
+		VotingPluginUser user = plugin.getVotingPluginUserManager().getVotingPluginUser(player);
+		return user == null || user.getJavaUUID() == null ? player.getUniqueId() : user.getJavaUUID();
+	}
+
+	private static boolean isBlank(String s) {
+		return s == null || s.trim().isEmpty() || "null".equalsIgnoreCase(s.trim());
+	}
+
+	private void clearPlaceholderCachesIfOffline(UUID uuid) {
+		PlaceHolders placeholders = plugin.getPlaceholders();
+		if (placeholders != null) {
+			plugin.getPlaceholderPlayerPresence().runIfOffline(uuid, () -> placeholders.onLogout(uuid));
+		}
+	}
 
 	/**
 	 * On AdvancedCore login event (post-auth / delayed login).
 	 *
 	 * @param event the event
 	 */
-	@EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
-	public void onPlayerLogin(AdvancedCoreLoginEvent event) {
-		if (event == null || !plugin.isMySQLOkay() || event.isCancelled() || event.getUser() == null) {
+	@EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+	public void onPlayerLogin(AdvancedCoreLoginEvent event) {
+		if (event == null || !plugin.isMySQLOkay() || event.isCancelled() || event.getUser() == null) {
 			return;
 		}
 
@@ -57,9 +80,12 @@ public void onPlayerLogin(AdvancedCoreLoginEvent event) {
 			return;
 		}
 
-		Player player = event.getPlayer();
-
-		if (player != null && player.isOp() && plugin.isYmlError()) {
+		Player player = event.getPlayer();
+		if (player != null) {
+			plugin.getPlaceholderPlayerPresence().playerOnline(user.getJavaUUID(), player);
+		}
+
+		if (player != null && player.isOp() && plugin.isYmlError()) {
 			user.sendMessage("&cVotingPlugin: Detected yml error, please check console for details");
 		}
 
@@ -93,7 +119,11 @@ public void onPlayerQuit(PlayerQuitEvent event) {
 		final Player player = event.getPlayer();
 		if (player == null) {
 			return;
-		}
+		}
+		UUID placeholderUuid = plugin.getPlaceholderPlayerPresence().storageUuid(player);
+		if (placeholderUuid == null) placeholderUuid = placeholderUuid(player);
+		boolean retiredPresence = plugin.getPlaceholderPlayerPresence().playerOffline(placeholderUuid, player);
+		if (retiredPresence) clearPlaceholderCachesIfOffline(placeholderUuid);
 
 		if (plugin.getBungeeSettings().isUseBungeecoord()) {
 			plugin.getBackendProxyHandler().playerOffline(player.getName());
@@ -117,10 +147,10 @@ public void run() {
 					return;
 				}
 
-				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
-				user.logoutRewards();
-				plugin.getPlaceholders().onLogout(user);
-			}
-		});
+				user.userDataFetechMode(UserDataFetchMode.NO_CACHE);
+				user.logoutRewards();
+				clearPlaceholderCachesIfOffline(user.getJavaUUID());
+			}
+		});
 	}
 }