Initial commit

src/main/java/me/youhavetrouble/notjustnameplates/NotJustNameplates.java

@@ -0,0 +1,17 @@
+package me.youhavetrouble.notjustnameplates;
+
+import org.bukkit.plugin.java.JavaPlugin;
+
+public final class NotJustNameplates extends JavaPlugin {
+
+    @Override
+    public void onEnable() {
+        // Plugin startup logic
+
+    }
+
+    @Override
+    public void onDisable() {
+        // Plugin shutdown logic
+    }
+}

src/main/java/me/youhavetrouble/notjustnameplates/listeners/TeamManagementListener.java

@@ -0,0 +1,69 @@
+package me.youhavetrouble.notjustnameplates.listeners;
+
+import me.youhavetrouble.notjustnameplates.teams.PacketTeam;
+import net.minecraft.network.protocol.game.ClientboundSetPlayerTeamPacket;
+import net.minecraft.world.scores.PlayerTeam;
+import net.minecraft.world.scores.Scoreboard;
+import org.bukkit.craftbukkit.v1_20_R1.entity.CraftPlayer;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerJoinEvent;
+import org.bukkit.event.player.PlayerQuitEvent;
+
+import java.util.HashSet;
+
+public class PlayerJoinLeaveListener implements Listener {
+
+    private final Scoreboard scoreboard = new Scoreboard();
+    private final PlayerTeam team = new PlayerTeam(scoreboard, "notjustnameplates");
+    private final HashSet<String> players = new HashSet<>();
+
+    public PlayerJoinLeaveListener() {
+        team.setNameTagVisibility(PlayerTeam.Visibility.NEVER);
+    }
+
+    @EventHandler(ignoreCancelled = true, priority = EventPriority.HIGHEST)
+    public void onPlayerJoin(PlayerJoinEvent event) {
+        Player joiner = event.getPlayer();
+        for (Player player : event.getPlayer().getServer().getOnlinePlayers()) {
+            addPlayerToTeam(joiner, player);
+        }
+        PacketTeam.sendTeamMembers(joiner);
+    }
+
+    @EventHandler(ignoreCancelled = true, priority = EventPriority.HIGHEST)
+    public void onPlayerQuit(PlayerQuitEvent event) {
+        Player leaver = event.getPlayer();
+        for (Player player : event.getPlayer().getServer().getOnlinePlayers()) {
+            removePlayerFromTeam(leaver, player);
+        }
+    }
+
+    private void addPlayerToTeam(Player player, Player target) {
+        CraftPlayer craftPlayer = (CraftPlayer) target;
+        players.add(player.getName());
+
+        ClientboundSetPlayerTeamPacket teamCreatePacket = ClientboundSetPlayerTeamPacket.createAddOrModifyPacket(team, true);
+        craftPlayer.getHandle().connection.send(teamCreatePacket);
+
+        ClientboundSetPlayerTeamPacket packet = ClientboundSetPlayerTeamPacket.createPlayerPacket(team, player.getName(), ClientboundSetPlayerTeamPacket.Action.ADD);
+
+        craftPlayer.getHandle().connection.send(packet);
+    }
+
+    private void removePlayerFromTeam(Player player, Player target) {
+        ClientboundSetPlayerTeamPacket packet = ClientboundSetPlayerTeamPacket.createPlayerPacket(team, player.getName(), ClientboundSetPlayerTeamPacket.Action.REMOVE);
+        CraftPlayer craftPlayer = (CraftPlayer) target;
+        players.remove(player.getName());
+        craftPlayer.getHandle().connection.send(packet);
+    }
+
+    private void sendTeamMembers(Player target) {
+        ClientboundSetPlayerTeamPacket packet = ClientboundSetPlayerTeamPacket.createMultiplePlayerPacket(team, players, ClientboundSetPlayerTeamPacket.Action.ADD);
+        CraftPlayer craftPlayer = (CraftPlayer) target;
+        craftPlayer.getHandle().connection.send(packet);
+    }
+
+}

src/main/java/me/youhavetrouble/notjustnameplates/nameplates/Nameplate.java

@@ -0,0 +1,2 @@
+package me.youhavetrouble.notjustnameplates.nameplates;public class Nameplate {
+}