Add /viaversion player <name|*> command (#3932)

common/src/main/java/com/viaversion/viaversion/commands/ViaCommandHandler.java

@@ -30,6 +30,7 @@ import com.viaversion.viaversion.commands.defaultsubs.DumpSubCmd;
 import com.viaversion.viaversion.commands.defaultsubs.ListSubCmd;
 import com.viaversion.viaversion.commands.defaultsubs.PPSSubCmd;
 import com.viaversion.viaversion.commands.defaultsubs.ReloadSubCmd;
+import com.viaversion.viaversion.commands.defaultsubs.PlayerSubCmd;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -194,5 +195,6 @@ public abstract class ViaCommandHandler implements ViaVersionCommand {
         registerSubCommand(new DontBugMeSubCmd());
         registerSubCommand(new AutoTeamSubCmd());
         registerSubCommand(new ReloadSubCmd());
+        registerSubCommand(new PlayerSubCmd());
     }
 }

common/src/main/java/com/viaversion/viaversion/commands/defaultsubs/PlayerSubCmd.java

@@ -0,0 +1,75 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.commands.defaultsubs;
+
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.command.ViaCommandSender;
+import com.viaversion.viaversion.api.command.ViaSubCommand;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import java.util.ArrayList;
+import java.util.List;
+
+public class PlayerSubCmd implements ViaSubCommand {
+    @Override
+    public String name() {
+        return "player";
+    }
+
+    @Override
+    public String description() {
+        return "Shows connection information about one or all players.";
+    }
+
+    @Override
+    public String usage() {
+        return "player <name|*>";
+    }
+
+    @Override
+    public boolean execute(final ViaCommandSender sender, final String[] args) {
+        if (args.length == 0) {
+            return false;
+        }
+        for (final UserConnection connection : Via.getManager().getConnectionManager().getConnections()) {
+            final ProtocolInfo info = connection.getProtocolInfo();
+            if (args[0].equalsIgnoreCase(info.getUsername()) || args[0].equals("*")) {
+                sendMessage(sender, "&7[&6" + info.getUsername() + "&7] UUID: &2" + info.getUuid() + " &7Client-Protocol: &2" + info.protocolVersion().getName() + " &7Server-Protocol: &2" + info.serverProtocolVersion().getName());
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public List<String> onTabComplete(final ViaCommandSender sender, final String[] args) {
+        if (args.length == 1) {
+            final String input = args[0].toLowerCase();
+
+            final List<String> matches = new ArrayList<>();
+            for (final UserConnection connection : Via.getManager().getConnectionManager().getConnections()) {
+                final String name = connection.getProtocolInfo().getUsername();
+                if (input.isEmpty() || name.toLowerCase().startsWith(input)) {
+                    matches.add(name);
+                }
+            }
+            matches.add("*");
+            return matches;
+        }
+        return ViaSubCommand.super.onTabComplete(sender, args);
+    }
+}