Paper/patches/server/0161-AsyncTabCompleteEvent.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jason Penilla <11360596+jpenilla@users.noreply.github.com>
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

Co-authored-by: Aikar <aikar@aikar.co>

diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 414077a1fed2955bd64ac7091af1daeda2a92e2c..79d9a58c66382fd94ab5f6020285e341b0114f6a 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -722,21 +722,58 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
 
     }
 
+    // Paper start - AsyncTabCompleteEvent
+    private static final java.util.concurrent.ExecutorService TAB_COMPLETE_EXECUTOR = java.util.concurrent.Executors.newFixedThreadPool(4,
+        new com.google.common.util.concurrent.ThreadFactoryBuilder().setDaemon(true).setNameFormat("Async Tab Complete Thread - #%d").setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER)).build());
+    // Paper end - AsyncTabCompleteEvent
     @Override
     public void handleCustomCommandSuggestions(ServerboundCommandSuggestionPacket packet) {
-        PacketUtils.ensureRunningOnSameThread(packet, this, this.player.serverLevel());
+        // PacketUtils.ensureRunningOnSameThread(packet, this, this.player.serverLevel()); // Paper - AsyncTabCompleteEvent; run this async
         // CraftBukkit start
         if (!this.chatSpamThrottler.isIncrementAndUnderThreshold(1, 500) && !this.server.getPlayerList().isOp(this.player.getGameProfile()) && !this.server.isSingleplayerOwner(this.player.getGameProfile())) {
             this.disconnect(Component.translatable("disconnect.spam"));
             return;
         }
         // CraftBukkit end
+        // Paper start - AsyncTabCompleteEvent
+        TAB_COMPLETE_EXECUTOR.execute(() -> this.handleCustomCommandSuggestions0(packet));
+    }
+
+    private void handleCustomCommandSuggestions0(final ServerboundCommandSuggestionPacket packet) {
         StringReader stringreader = new StringReader(packet.getCommand());
 
         if (stringreader.canRead() && stringreader.peek() == '/') {
             stringreader.skip();
         }
 
+        final com.destroystokyo.paper.event.server.AsyncTabCompleteEvent event = new com.destroystokyo.paper.event.server.AsyncTabCompleteEvent(this.getCraftPlayer(), packet.getCommand(), true, null);
+        event.callEvent();
+        final List<com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion> completions = event.isCancelled() ? com.google.common.collect.ImmutableList.of() : event.completions();
+        // If the event isn't handled, we can assume that we have no completions, and so we'll ask the server
+        if (!event.isHandled()) {
+            if (event.isCancelled()) {
+                return;
+            }
+
+            // This needs to be on main
+            this.server.scheduleOnMain(() -> this.sendServerSuggestions(packet, stringreader));
+        } else if (!completions.isEmpty()) {
+            final com.mojang.brigadier.suggestion.SuggestionsBuilder builder0 = new com.mojang.brigadier.suggestion.SuggestionsBuilder(packet.getCommand(), stringreader.getTotalLength());
+            final com.mojang.brigadier.suggestion.SuggestionsBuilder builder = builder0.createOffset(builder0.getInput().lastIndexOf(' ') + 1);
+            for (final com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion completion : completions) {
+                final Integer intSuggestion = com.google.common.primitives.Ints.tryParse(completion.suggestion());
+                if (intSuggestion != null) {
+                    builder.suggest(intSuggestion, PaperAdventure.asVanilla(completion.tooltip()));
+                } else {
+                    builder.suggest(completion.suggestion(), PaperAdventure.asVanilla(completion.tooltip()));
+                }
+            }
+            this.connection.send(new ClientboundCommandSuggestionsPacket(packet.getId(), builder.buildFuture().join()));
+        }
+    }
+
+    private void sendServerSuggestions(final ServerboundCommandSuggestionPacket packet, final StringReader stringreader) {
+        // Paper end - AsyncTabCompleteEvent
         ParseResults<CommandSourceStack> parseresults = this.server.getCommands().getDispatcher().parse(stringreader, this.player.createCommandSourceStack());
 
         this.server.getCommands().getDispatcher().getCompletionSuggestions(parseresults).thenAccept((suggestions) -> {
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index 2d1f92f75e83aacd39440d2619befdf6cd545af4..1dd440057cb1d8acce7bfaa7ab1814937a4c63af 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -2297,7 +2297,7 @@ public final class CraftServer implements Server {
             offers = this.tabCompleteChat(player, message);
         }
 
-        TabCompleteEvent tabEvent = new TabCompleteEvent(player, message, offers);
+        TabCompleteEvent tabEvent = new TabCompleteEvent(player, message, offers, message.startsWith("/") || forceCommand, pos != null ? io.papermc.paper.util.MCUtil.toLocation(((CraftWorld) player.getWorld()).getHandle(), BlockPos.containing(pos)) : null); // Paper - AsyncTabCompleteEvent
         this.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 0b27172073530617a6e0b2b83fe1e9d231653b8d..15bc85f4799a4b23edd2f1e93f1794de5ca3e8e3 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/ConsoleCommandCompleter.java
@@ -28,6 +28,61 @@ 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
+        final com.destroystokyo.paper.event.server.AsyncTabCompleteEvent event =
+            new com.destroystokyo.paper.event.server.AsyncTabCompleteEvent(server.getConsoleSender(), buffer, true, null);
+        event.callEvent();
+        final List<com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion> completions = event.isCancelled() ? com.google.common.collect.ImmutableList.of() : event.completions();
+
+        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<com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion> finalCompletions = new java.util.ArrayList<>(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.stream()
+                                .map(com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion::suggestion)
+                                .collect(java.util.stream.Collectors.toList()));
+                        return syncEvent.callEvent() ? syncEvent.getCompletions() : com.google.common.collect.ImmutableList.of();
+                    }
+                };
+                server.getServer().processQueue.add(syncCompletions);
+                try {
+                    final List<String> legacyCompletions = syncCompletions.get();
+                    completions.removeIf(it -> !legacyCompletions.contains(it.suggestion())); // remove any suggestions that were removed
+                    // add any new suggestions
+                    for (final String completion : legacyCompletions) {
+                        if (notNewSuggestion(completions, completion)) {
+                            continue;
+                        }
+                        completions.add(com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion.completion(completion));
+                    }
+                } catch (InterruptedException | ExecutionException e1) {
+                    e1.printStackTrace();
+                }
+            }
+
+            if (!completions.isEmpty()) {
+                for (final com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion completion : completions) {
+                    if (completion.suggestion().isEmpty()) {
+                        continue;
+                    }
+                    candidates.add(new Candidate(
+                        completion.suggestion(),
+                        completion.suggestion(),
+                        null,
+                        io.papermc.paper.adventure.PaperAdventure.PLAIN.serializeOr(completion.tooltip(), null),
+                        null,
+                        null,
+                        false
+                    ));
+                }
+            }
+            return;
+        }
+
         // Paper end
         Waitable<List<String>> waitable = new Waitable<List<String>>() {
             @Override
@@ -73,4 +128,15 @@ public class ConsoleCommandCompleter implements Completer {
             Thread.currentThread().interrupt();
         }
     }
+
+    // Paper start
+    private boolean notNewSuggestion(final List<com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion> completions, final String completion) {
+        for (final com.destroystokyo.paper.event.server.AsyncTabCompleteEvent.Completion it : completions) {
+            if (it.suggestion().equals(completion)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    // Paper end
 }