From d1bfb9e1628d208a40b8de3f9b42c73d593c90aa Mon Sep 17 00:00:00 2001
From: Tux <write@imaginarycode.com>
Date: Tue, 25 Aug 2015 20:12:55 -0400
Subject: [PATCH] If we find an async ping event-hostile plugin (currently only
 ServerListPlus), run the ping handling handler synchronously.

This is meant as a move to attempt to introduce a better mechanism for handling async events in a more sane way.
---
 .../redisbungee/RedisBungeeListener.java      | 49 ++++++++++++++-----
 1 file changed, 36 insertions(+), 13 deletions(-)

diff --git a/src/main/java/com/imaginarycode/minecraft/redisbungee/RedisBungeeListener.java b/src/main/java/com/imaginarycode/minecraft/redisbungee/RedisBungeeListener.java
index e22175f..001c577 100644
--- a/src/main/java/com/imaginarycode/minecraft/redisbungee/RedisBungeeListener.java
+++ b/src/main/java/com/imaginarycode/minecraft/redisbungee/RedisBungeeListener.java
@@ -28,6 +28,7 @@ package com.imaginarycode.minecraft.redisbungee;
 
 import com.google.common.base.Joiner;
 import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Multimap;
 import com.google.common.io.ByteArrayDataInput;
 import com.google.common.io.ByteArrayDataOutput;
@@ -37,6 +38,7 @@ import com.imaginarycode.minecraft.redisbungee.util.RedisCallable;
 import lombok.AllArgsConstructor;
 import net.md_5.bungee.api.AbstractReconnectHandler;
 import net.md_5.bungee.api.ChatColor;
+import net.md_5.bungee.api.ProxyServer;
 import net.md_5.bungee.api.ServerPing;
 import net.md_5.bungee.api.chat.BaseComponent;
 import net.md_5.bungee.api.chat.ComponentBuilder;
@@ -69,6 +71,8 @@ public class RedisBungeeListener implements Listener {
     private final RedisBungee plugin;
     private final List<InetAddress> exemptAddresses;
 
+    private static final List<String> ASYNC_PING_EVENT_HOSTILE = ImmutableList.of("ServerListPlus");
+
     @EventHandler(priority = EventPriority.LOWEST)
     public void onLogin(final LoginEvent event) {
         event.registerIntent(plugin);
@@ -179,20 +183,39 @@ public class RedisBungeeListener implements Listener {
             return;
         }
 
-        event.registerIntent(plugin);
-        plugin.getProxy().getScheduler().runAsync(plugin, new Runnable() {
-            @Override
-            public void run() {
-                ServerPing old = event.getResponse();
-                ServerPing reply = new ServerPing();
-                reply.setPlayers(new ServerPing.Players(old.getPlayers().getMax(), plugin.getCount(), old.getPlayers().getSample()));
-                reply.setDescription(old.getDescription());
-                reply.setFavicon(old.getFaviconObject());
-                reply.setVersion(old.getVersion());
-                event.setResponse(reply);
-                event.completeIntent(plugin);
+        boolean runAsync = true;
+        for (String s : ASYNC_PING_EVENT_HOSTILE) {
+            if (ProxyServer.getInstance().getPluginManager().getPlugin(s) != null) {
+                runAsync = false;
+                break;
             }
-        });
+        }
+
+        if (runAsync) {
+            event.registerIntent(plugin);
+            plugin.getProxy().getScheduler().runAsync(plugin, new Runnable() {
+                @Override
+                public void run() {
+                    ServerPing old = event.getResponse();
+                    ServerPing reply = new ServerPing();
+                    reply.setPlayers(new ServerPing.Players(old.getPlayers().getMax(), plugin.getCount(), old.getPlayers().getSample()));
+                    reply.setDescription(old.getDescription());
+                    reply.setFavicon(old.getFaviconObject());
+                    reply.setVersion(old.getVersion());
+                    event.setResponse(reply);
+                    event.completeIntent(plugin);
+                }
+            });
+        } else {
+            // Async ping event will not work as an async-hostile plugin was found, so perform the ping modification synchronously.
+            ServerPing old = event.getResponse();
+            ServerPing reply = new ServerPing();
+            reply.setPlayers(new ServerPing.Players(old.getPlayers().getMax(), plugin.getCount(), old.getPlayers().getSample()));
+            reply.setDescription(old.getDescription());
+            reply.setFavicon(old.getFaviconObject());
+            reply.setVersion(old.getVersion());
+            event.setResponse(reply);
+        }
     }
 
     @EventHandler