Add console tab complete, shutdown command, gracefully kick players.

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -10,6 +10,7 @@ import com.velocitypowered.api.proxy.ProxyServer;
 import com.velocitypowered.natives.util.Natives;
 import com.velocitypowered.network.ConnectionManager;
 import com.velocitypowered.proxy.command.ServerCommand;
+import com.velocitypowered.proxy.command.ShutdownCommand;
 import com.velocitypowered.proxy.command.VelocityCommand;
 import com.velocitypowered.proxy.config.VelocityConfiguration;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
@@ -21,6 +22,7 @@ import com.velocitypowered.proxy.util.EncryptionUtils;
 import com.velocitypowered.proxy.util.ServerMap;
 import io.netty.bootstrap.Bootstrap;
 import net.kyori.text.Component;
+import net.kyori.text.TextComponent;
 import net.kyori.text.serializer.ComponentSerializers;
 import net.kyori.text.serializer.GsonComponentSerializer;
 import org.apache.logging.log4j.LogManager;
@@ -50,7 +52,8 @@ public class VelocityServer implements ProxyServer {
     private KeyPair serverKeyPair;
     private final ServerMap servers = new ServerMap();
     private final CommandManager commandManager = new CommandManager();
-    private final AtomicBoolean shutdown = new AtomicBoolean(false);
+    private final AtomicBoolean shutdownInProgress = new AtomicBoolean(false);
+    private boolean shutdown = false;
 
     private final Map<UUID, ConnectedPlayer> connectionsByUuid = new ConcurrentHashMap<>();
     private final Map<String, ConnectedPlayer> connectionsByName = new ConcurrentHashMap<>();
@@ -69,6 +72,7 @@ public class VelocityServer implements ProxyServer {
     private VelocityServer() {
         commandManager.registerCommand("velocity", new VelocityCommand());
         commandManager.registerCommand("server", new ServerCommand());
+        commandManager.registerCommand("shutdown", new ShutdownCommand());
     }
 
     public static VelocityServer getServer() {
@@ -136,13 +140,19 @@ public class VelocityServer implements ProxyServer {
     }
 
     public boolean isShutdown() {
-        return shutdown.get();
+        return shutdown;
     }
 
     public void shutdown() {
-        if (!shutdown.compareAndSet(false, true)) return;
+        if (!shutdownInProgress.compareAndSet(false, true)) return;
         logger.info("Shutting down the proxy...");
+
+        for (ConnectedPlayer player : ImmutableList.copyOf(connectionsByUuid.values())) {
+            player.close(TextComponent.of("Proxy shutting down."));
+        }
+
         this.cm.shutdown();
+        shutdown = true;
     }
 
     public NettyHttpClient getHttpClient() {

proxy/src/main/java/com/velocitypowered/proxy/command/CommandManager.java

@@ -1,12 +1,15 @@
 package com.velocitypowered.proxy.command;
 
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
 import com.velocitypowered.api.command.CommandExecutor;
 import com.velocitypowered.api.command.CommandInvoker;
 
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 public class CommandManager {
     private final Map<String, CommandExecutor> executors = new HashMap<>();
@@ -45,4 +48,33 @@ public class CommandManager {
             throw new RuntimeException("Unable to invoke command " + cmdLine + " for " + invoker, e);
         }
     }
+
+    public List<String> offerSuggestions(CommandInvoker invoker, String cmdLine) {
+        Preconditions.checkNotNull(invoker, "invoker");
+        Preconditions.checkNotNull(cmdLine, "cmdLine");
+
+        String[] split = cmdLine.split(" ", -1);
+        if (split.length == 0) {
+            return ImmutableList.of();
+        }
+
+        String command = split[0];
+        if (split.length == 1) {
+            return executors.keySet().stream()
+                    .filter(cmd -> cmd.regionMatches(true, 0, command, 0, command.length()))
+                    .collect(Collectors.toList());
+        }
+
+        String[] actualArgs = Arrays.copyOfRange(split, 1, split.length);
+        CommandExecutor executor = executors.get(command);
+        if (executor == null) {
+            return ImmutableList.of();
+        }
+
+        try {
+            return executor.suggest(invoker, actualArgs);
+        } catch (Exception e) {
+            throw new RuntimeException("Unable to invoke suggestions for command " + command + " for " + invoker, e);
+        }
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/ServerCommand.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.command;
 
+import com.google.common.collect.ImmutableList;
 import com.velocitypowered.api.command.CommandExecutor;
 import com.velocitypowered.api.command.CommandInvoker;
 import com.velocitypowered.api.proxy.Player;
@@ -9,6 +10,7 @@ import net.kyori.text.TextComponent;
 import net.kyori.text.format.TextColor;
 
 import javax.annotation.Nonnull;
+import java.util.List;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
@@ -38,4 +40,20 @@ public class ServerCommand implements CommandExecutor {
             player.sendMessage(TextComponent.of("Available servers: " + serverList, TextColor.YELLOW));
         }
     }
+
+    @Override
+    public List<String> suggest(@Nonnull CommandInvoker invoker, @Nonnull String[] currentArgs) {
+        if (currentArgs.length == 0) {
+            return VelocityServer.getServer().getAllServers().stream()
+                    .map(ServerInfo::getName)
+                    .collect(Collectors.toList());
+        } else if (currentArgs.length == 1) {
+            return VelocityServer.getServer().getAllServers().stream()
+                    .map(ServerInfo::getName)
+                    .filter(name -> name.regionMatches(true, 0, currentArgs[0], 0, currentArgs[0].length()))
+                    .collect(Collectors.toList());
+        } else {
+            return ImmutableList.of();
+        }
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/ShutdownCommand.java

@@ -0,0 +1,20 @@
+package com.velocitypowered.proxy.command;
+
+import com.velocitypowered.api.command.CommandExecutor;
+import com.velocitypowered.api.command.CommandInvoker;
+import com.velocitypowered.proxy.VelocityServer;
+import net.kyori.text.TextComponent;
+import net.kyori.text.format.TextColor;
+
+import javax.annotation.Nonnull;
+
+public class ShutdownCommand implements CommandExecutor {
+    @Override
+    public void execute(@Nonnull CommandInvoker invoker, @Nonnull String[] args) {
+        if (invoker != VelocityServer.getServer().getConsoleCommandInvoker()) {
+            invoker.sendMessage(TextComponent.of("You are not allowed to use this command.", TextColor.RED));
+            return;
+        }
+        VelocityServer.getServer().shutdown();
+    }
+}

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommand.java

@@ -16,7 +16,7 @@ public class VelocityCommand implements CommandExecutor {
         TextComponent thisIsVelocity = TextComponent.builder()
                 .content("This is ")
                 .append(TextComponent.of("Velocity " + implVersion, TextColor.DARK_AQUA))
-                .append(TextComponent.of(", the next generation Minecraft: Java Edition proxy.", TextColor.WHITE))
+                .append(TextComponent.of(", the next generation Minecraft: Java Edition proxy.").resetStyle())
                 .build();
         TextComponent velocityInfo = TextComponent.builder()
                 .content("Copyright 2018 Velocity Contributors. Velocity is freely licensed under the terms of the " +
@@ -28,7 +28,7 @@ public class VelocityCommand implements CommandExecutor {
                         .color(TextColor.GREEN)
                         .clickEvent(new ClickEvent(ClickEvent.Action.OPEN_URL, "https://www.velocitypowered.com"))
                         .build())
-                .append(TextComponent.of(" or the ", TextColor.WHITE))
+                .append(TextComponent.of(" or the ").resetStyle())
                 .append(TextComponent.builder("Velocity GitHub")
                         .color(TextColor.GREEN)
                         .clickEvent(new ClickEvent(ClickEvent.Action.OPEN_URL, "https://github.com/astei/velocity"))

proxy/src/main/java/com/velocitypowered/proxy/console/VelocityConsole.java

@@ -1,9 +1,12 @@
 package com.velocitypowered.proxy.console;
 
 import com.velocitypowered.proxy.VelocityServer;
+import net.kyori.text.TextComponent;
+import net.kyori.text.format.TextColor;
 import net.minecrell.terminalconsole.SimpleTerminalConsole;
-import org.jline.reader.LineReader;
-import org.jline.reader.LineReaderBuilder;
+import org.jline.reader.*;
+
+import java.util.List;
 
 public final class VelocityConsole extends SimpleTerminalConsole {
 
@@ -16,8 +19,14 @@ public final class VelocityConsole extends SimpleTerminalConsole {
     @Override
     protected LineReader buildReader(LineReaderBuilder builder) {
         return super.buildReader(builder
-            .appName("Velocity")
-            // TODO: Command completion
+                .appName("Velocity")
+                .completer((reader, parsedLine, list) -> {
+                    List<String> offers = server.getCommandManager().offerSuggestions(server.getConsoleCommandInvoker(), parsedLine.line());
+                    for (String offer : offers) {
+                        if (offer.isEmpty()) continue;
+                        list.add(new Candidate(offer));
+                    }
+                })
         );
     }
 
@@ -28,7 +37,9 @@ public final class VelocityConsole extends SimpleTerminalConsole {
 
     @Override
     protected void runCommand(String command) {
-        this.server.getCommandManager().execute(this.server.getConsoleCommandInvoker(), command);
+        if (!this.server.getCommandManager().execute(this.server.getConsoleCommandInvoker(), command)) {
+            server.getConsoleCommandInvoker().sendMessage(TextComponent.of("Command not found.", TextColor.RED));
+        }
     }
 
     @Override