From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 19 Apr 2020 18:15:29 -0400
Subject: [PATCH] Implement Brigadier Mojang API

Adds AsyncPlayerSendCommandsEvent
  - Allows modifying on a per command basis what command data they see.

Adds CommandRegisteredEvent
  - Allows manipulating the CommandNode to add more children/metadata for the client

diff --git a/build.gradle.kts b/build.gradle.kts
index 125630037713c4790636ffd11b14b2c1d83a085a..898e2efb764e5bd97ab4e757e6c4c27fc4efdbef 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -12,6 +12,7 @@ repositories {
 
 dependencies {
     implementation(project(":paper-api"))
+    implementation(project(":paper-mojangapi"))
     // Paper start
     implementation("org.jline:jline-terminal-jansi:3.21.0")
     implementation("net.minecrell:terminalconsoleappender:1.3.0")
diff --git a/src/main/java/net/minecraft/commands/CommandSourceStack.java b/src/main/java/net/minecraft/commands/CommandSourceStack.java
index 9f79c949d18c1ff3bdb49780fcecfc75366a8ff6..530a09fa3c9155459c6a4519e3412408ae658145 100644
--- a/src/main/java/net/minecraft/commands/CommandSourceStack.java
+++ b/src/main/java/net/minecraft/commands/CommandSourceStack.java
@@ -38,7 +38,7 @@ import net.minecraft.world.phys.Vec2;
 import net.minecraft.world.phys.Vec3;
 import com.mojang.brigadier.tree.CommandNode; // CraftBukkit
 
-public class CommandSourceStack implements SharedSuggestionProvider {
+public class CommandSourceStack implements SharedSuggestionProvider, com.destroystokyo.paper.brigadier.BukkitBrigadierCommandSource { // Paper
 
     public static final SimpleCommandExceptionType ERROR_NOT_PLAYER = new SimpleCommandExceptionType(new TranslatableComponent("permissions.requires.player"));
     public static final SimpleCommandExceptionType ERROR_NOT_ENTITY = new SimpleCommandExceptionType(new TranslatableComponent("permissions.requires.entity"));
@@ -155,6 +155,25 @@ public class CommandSourceStack implements SharedSuggestionProvider {
         return this.textName;
     }
 
+    // Paper start
+    @Override
+    public org.bukkit.entity.Entity getBukkitEntity() {
+        return getEntity() != null ? getEntity().getBukkitEntity() : null;
+    }
+
+    @Override
+    public org.bukkit.World getBukkitWorld() {
+        return getLevel() != null ? getLevel().getWorld() : null;
+    }
+
+    @Override
+    public org.bukkit.Location getBukkitLocation() {
+        Vec3 pos = getPosition();
+        org.bukkit.World world = getBukkitWorld();
+        return world != null && pos != null ? new org.bukkit.Location(world, pos.x, pos.y, pos.z) : null;
+    }
+    // Paper end
+
     @Override
     public boolean hasPermission(int level) {
         // CraftBukkit start
diff --git a/src/main/java/net/minecraft/commands/Commands.java b/src/main/java/net/minecraft/commands/Commands.java
index ee31455158afbed8f3bbac57d2f41a59d01a0670..4049576478efed97092b7e1b3d40afda6b114d68 100644
--- a/src/main/java/net/minecraft/commands/Commands.java
+++ b/src/main/java/net/minecraft/commands/Commands.java
@@ -369,6 +369,7 @@ public class Commands {
             bukkit.add(node.getName());
         }
         // Paper start - Async command map building
+        new com.destroystokyo.paper.event.brigadier.AsyncPlayerSendCommandsEvent<CommandSourceStack>(player.getBukkitEntity(), (RootCommandNode) rootcommandnode, false).callEvent(); // Paper
         MinecraftServer.getServer().execute(() -> {
            runSync(player, bukkit, rootcommandnode);
         });
@@ -376,6 +377,7 @@ public class Commands {
 
     private void runSync(ServerPlayer player, Collection<String> bukkit, RootCommandNode<SharedSuggestionProvider> rootcommandnode) {
         // Paper end - Async command map building
+        new com.destroystokyo.paper.event.brigadier.AsyncPlayerSendCommandsEvent<CommandSourceStack>(player.getBukkitEntity(), (RootCommandNode) rootcommandnode, false).callEvent(); // Paper
         PlayerCommandSendEvent event = new PlayerCommandSendEvent(player.getBukkitEntity(), new LinkedHashSet<>(bukkit));
         event.getPlayer().getServer().getPluginManager().callEvent(event);
 
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index b1ea73320b7927b23d48ee6e80b63b37d1806c97..e2044745f490f99deb993e42385d71fa8d927ab1 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -746,8 +746,12 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
                     ParseResults<CommandSourceStack> parseresults = this.server.getCommands().getDispatcher().parse(stringreader, this.player.createCommandSourceStack());
 
                     this.server.getCommands().getDispatcher().getCompletionSuggestions(parseresults).thenAccept((suggestions) -> {
-                        if (suggestions.isEmpty()) return; // CraftBukkit - don't send through empty suggestions - prevents [<args>] from showing for plugins with nothing more to offer
-                        this.connection.send(new ClientboundCommandSuggestionsPacket(packet.getId(), suggestions));
+                        // Paper start
+                        com.destroystokyo.paper.event.brigadier.AsyncPlayerSendSuggestionsEvent suggestEvent = new com.destroystokyo.paper.event.brigadier.AsyncPlayerSendSuggestionsEvent(this.getCraftPlayer(), suggestions, buffer);
+                        suggestEvent.setCancelled(suggestions.isEmpty());
+                        if (!suggestEvent.callEvent()) return;
+                        this.connection.send(new ClientboundCommandSuggestionsPacket(packet.getId(), (com.mojang.brigadier.suggestion.Suggestions) suggestEvent.getSuggestions())); // CraftBukkit - decompile error // Paper
+                        // Paper end
                     });
                 });
             }
@@ -756,7 +760,11 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
 
             builder = builder.createOffset(builder.getInput().lastIndexOf(' ') + 1);
             completions.forEach(builder::suggest);
-            player.connection.send(new ClientboundCommandSuggestionsPacket(packet.getId(), builder.buildFuture().join()));
+            com.mojang.brigadier.suggestion.Suggestions suggestions = builder.buildFuture().join();
+            com.destroystokyo.paper.event.brigadier.AsyncPlayerSendSuggestionsEvent suggestEvent = new com.destroystokyo.paper.event.brigadier.AsyncPlayerSendSuggestionsEvent(this.getCraftPlayer(), suggestions, buffer);
+            suggestEvent.setCancelled(suggestions.isEmpty());
+            if (!suggestEvent.callEvent()) return;
+            this.connection.send(new ClientboundCommandSuggestionsPacket(packet.getId(), suggestEvent.getSuggestions()));
         }
         // Paper end - async tab completion
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
index 21971d52fa8ed92c946c519ba93a39aceae10f5f..0bba36d18d56a4dc2d6c6fb7969e5e6f0e1da404 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
@@ -17,7 +17,7 @@ import net.minecraft.commands.CommandSourceStack;
 import org.bukkit.command.Command;
 import org.bukkit.craftbukkit.CraftServer;
 
-public class BukkitCommandWrapper implements com.mojang.brigadier.Command<CommandSourceStack>, Predicate<CommandSourceStack>, SuggestionProvider<CommandSourceStack> {
+public class BukkitCommandWrapper implements com.mojang.brigadier.Command<CommandSourceStack>, Predicate<CommandSourceStack>, SuggestionProvider<CommandSourceStack>, com.destroystokyo.paper.brigadier.BukkitBrigadierCommand<CommandSourceStack> { // Paper
 
     private final CraftServer server;
     private final Command command;
@@ -28,10 +28,19 @@ public class BukkitCommandWrapper implements com.mojang.brigadier.Command<Comman
     }
 
     public LiteralCommandNode<CommandSourceStack> register(CommandDispatcher<CommandSourceStack> dispatcher, String label) {
-        return dispatcher.register(
-                LiteralArgumentBuilder.<CommandSourceStack>literal(label).requires(this).executes(this)
-                .then(RequiredArgumentBuilder.<CommandSourceStack, String>argument("args", StringArgumentType.greedyString()).suggests(this).executes(this))
-        );
+        // Paper start - Expose Brigadier to Paper-MojangAPI
+        com.mojang.brigadier.tree.RootCommandNode<CommandSourceStack> root = dispatcher.getRoot();
+        LiteralCommandNode<CommandSourceStack> literal = LiteralArgumentBuilder.<CommandSourceStack>literal(label).requires(this).executes(this).build();
+        com.mojang.brigadier.tree.ArgumentCommandNode<CommandSourceStack, String> defaultArgs = RequiredArgumentBuilder.<CommandSourceStack, String>argument("args", StringArgumentType.greedyString()).suggests(this).executes(this).build();
+        literal.addChild(defaultArgs);
+        com.destroystokyo.paper.event.brigadier.CommandRegisteredEvent<CommandSourceStack> event = new com.destroystokyo.paper.event.brigadier.CommandRegisteredEvent<>(label, this, this.command, root, literal, defaultArgs);
+        if (!event.callEvent()) {
+            return null;
+        }
+        literal = event.getLiteral();
+        root.addChild(literal);
+        return literal;
+        // Paper end
     }
 
     @Override