Paper/Spigot-Server-Patches/0252-AsyncTabCompleteEvent.patch

From 36595d8506ce4cb19d6e56d941f824b75bb190b7 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 26 Nov 2017 13:19:58 -0500
Subject: [PATCH] AsyncTabCompleteEvent

Let plugins be able to control tab completion of commands and chat async.

This will be useful for frameworks like ACF so we can define async safe completion handlers,
and avoid going to main for tab completions.

Especially useful if you need to query a database in order to obtain the results for tab
completion, such as offline players.

Also adds isCommand and getLocation to the sync TabCompleteEvent

diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index 89071db952..2ed59b4088 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -10,6 +10,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Set;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.logging.log4j.LogManager;
@@ -2277,24 +2278,45 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
         // CraftBukkit end
     }
 
-    public void a(PacketPlayInTabComplete packetplayintabcomplete) {
-        PlayerConnectionUtils.ensureMainThread(packetplayintabcomplete, this, this.player.x());
+    // Paper start - async tab completion
+    public void a(PacketPlayInTabComplete packet) {
         // CraftBukkit start
         if (chatSpamField.addAndGet(this, 10) > 500 && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) {
-            this.disconnect(new ChatMessage("disconnect.spam", new Object[0]));
+            minecraftServer.postToMainThread(() -> this.disconnect(new ChatMessage("disconnect.spam", new Object[0])));
             return;
         }
         // CraftBukkit end
-        ArrayList arraylist = Lists.newArrayList();
-        Iterator iterator = this.minecraftServer.tabCompleteCommand(this.player, packetplayintabcomplete.a(), packetplayintabcomplete.b(), packetplayintabcomplete.c()).iterator();
 
-        while (iterator.hasNext()) {
-            String s = (String) iterator.next();
+        com.destroystokyo.paper.event.server.AsyncTabCompleteEvent event;
+        java.util.List<String> completions = new ArrayList<>();
+        BlockPosition blockpos = packet.b();
+        String buffer = packet.a();
+        boolean isCommand = buffer.startsWith("/") || packet.c();
+        event = new com.destroystokyo.paper.event.server.AsyncTabCompleteEvent(this.getPlayer(), completions,
+            buffer, isCommand, blockpos != null ? MCUtil.toLocation(player.world, blockpos) : null);
+        event.callEvent();
+        completions = event.isCancelled() ? com.google.common.collect.ImmutableList.of() : event.getCompletions();
+        if (!event.isHandled()) {
+            // If the event isn't handled, we can assume that we have no completions, and so we'll ask the server
+
+            Waitable<java.util.List<String>> syncCompletions = new Waitable<java.util.List<String>>() {
+                @Override
+                protected java.util.List<String> evaluate() {
+                    return minecraftServer.tabCompleteCommand(player, buffer, blockpos, isCommand);
+                }
+            };
+            server.getServer().processQueue.add(syncCompletions);
+            try {
+                completions = syncCompletions.get();
+            } catch (InterruptedException | ExecutionException e1) {
+                e1.printStackTrace();
+            }
 
-            arraylist.add(s);
+            this.player.playerConnection.sendPacket(new PacketPlayOutTabComplete(completions.toArray(new String[completions.size()])));
+        } else if (!event.isCancelled()) {
+            this.player.playerConnection.sendPacket(new PacketPlayOutTabComplete(completions.toArray(new String[completions.size()])));
         }
-
-        this.player.playerConnection.sendPacket(new PacketPlayOutTabComplete((String[]) arraylist.toArray(new String[arraylist.size()])));
+        // Paper end
     }
 
     public void a(PacketPlayInSettings packetplayinsettings) {
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index 5b1aae5587..d6676074e6 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -1643,8 +1643,8 @@ public final class CraftServer implements Server {
         } else {
             offers = tabCompleteChat(player, message);
         }
-
-        TabCompleteEvent tabEvent = new TabCompleteEvent(player, message, offers);
+        
+        TabCompleteEvent tabEvent = new TabCompleteEvent(player, message, offers, message.startsWith("/") || forceCommand, pos != null ? MCUtil.toLocation(((CraftWorld) player.getWorld()).getHandle(), pos) : null); // Paper
         getPluginManager().callEvent(tabEvent);
 
         return tabEvent.isCancelled() ? Collections.EMPTY_LIST : tabEvent.getCompletions();
diff --git a/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java b/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java
index 1e3aae3b8f..95d13c146b 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java
@@ -28,6 +28,39 @@ public class ConsoleCommandCompleter implements Completer {
     public void complete(LineReader reader, ParsedLine line, List<Candidate> candidates) {
         final CraftServer server = this.server.server;
         final String buffer = line.line();
+        // Async Tab Complete
+        com.destroystokyo.paper.event.server.AsyncTabCompleteEvent event;
+        java.util.List<String> completions = new java.util.ArrayList<>();
+        event = new com.destroystokyo.paper.event.server.AsyncTabCompleteEvent(server.getConsoleSender(), completions,
+            buffer, true, null);
+        event.callEvent();
+        completions = event.isCancelled() ? com.google.common.collect.ImmutableList.of() : event.getCompletions();
+
+        if (event.isCancelled() || event.isHandled()) {
+            // Still fire sync event with the provided completions, if someone is listening
+            if (!event.isCancelled() && TabCompleteEvent.getHandlerList().getRegisteredListeners().length > 0) {
+                List<String> finalCompletions = completions;
+                Waitable<List<String>> syncCompletions = new Waitable<List<String>>() {
+                    @Override
+                    protected List<String> evaluate() {
+                        org.bukkit.event.server.TabCompleteEvent syncEvent = new org.bukkit.event.server.TabCompleteEvent(server.getConsoleSender(), buffer, finalCompletions);
+                        return syncEvent.callEvent() ? syncEvent.getCompletions() : com.google.common.collect.ImmutableList.of();
+                    }
+                };
+                server.getServer().processQueue.add(syncCompletions);
+                try {
+                    completions = syncCompletions.get();
+                } catch (InterruptedException | ExecutionException e1) {
+                    e1.printStackTrace();
+                }
+            }
+
+            if (!completions.isEmpty()) {
+                candidates.addAll(completions.stream().map(Candidate::new).collect(java.util.stream.Collectors.toList()));
+            }
+            return;
+        }
+
         // Paper end
         Waitable<List<String>> waitable = new Waitable<List<String>>() {
             @Override
-- 
2.18.0