Fix some instances of team-applied nametags not working

Fixes #3531

core/src/main/java/org/geysermc/geyser/entity/type/player/PlayerEntity.java

@@ -100,6 +100,7 @@ public class PlayerEntity extends LivingEntity {
         super(session, entityId, geyserId, uuid, EntityDefinitions.PLAYER, position, motion, yaw, pitch, headYaw);
 
         this.username = username;
+        this.nametag = username;
         this.texturesProperty = texturesProperty;
     }
 
@@ -119,7 +120,7 @@ public class PlayerEntity extends LivingEntity {
         }
 
         // The name can't be updated later (the entity metadata for it is ignored), so we need to check for this now
-        updateDisplayName(null, false);
+        updateDisplayName(session.getWorldCache().getScoreboard().getTeamFor(username));
 
         AddPlayerPacket addPlayerPacket = new AddPlayerPacket();
         addPlayerPacket.setUuid(uuid);
@@ -315,19 +316,10 @@ public class PlayerEntity extends LivingEntity {
     }
 
     //todo this will become common entity logic once UUID support is implemented for them
-    /**
-     * @param useGivenTeam even if there is no team, update the username in the entity metadata anyway, and don't look for a team
-     */
-    public void updateDisplayName(@Nullable Team team, boolean useGivenTeam) {
-        if (team == null && !useGivenTeam) {
-            // Only search for the team if we are not supposed to use the given team
-            // If the given team is null, this is intentional that we are being removed from the team
-            team = session.getWorldCache().getScoreboard().getTeamFor(username);
-        }
-
+    public void updateDisplayName(@Nullable Team team) {
         boolean needsUpdate;
-        String newDisplayName = this.username;
         if (team != null) {
+            String newDisplayName;
             if (team.isVisibleFor(session.getPlayerEntity().getUsername())) {
                 TeamColor color = team.getColor();
                 String chatColor = MessageTranslator.toChatColor(color);
@@ -339,23 +331,16 @@ public class PlayerEntity extends LivingEntity {
                 // The name is not visible to the session player; clear name
                 newDisplayName = "";
             }
-            needsUpdate = useGivenTeam && !newDisplayName.equals(nametag);
-            nametag = newDisplayName;
-            dirtyMetadata.put(EntityData.NAMETAG, newDisplayName);
-        } else if (useGivenTeam) {
-            // The name has reset, if it was previously something else
-            needsUpdate = !newDisplayName.equals(nametag);
-            dirtyMetadata.put(EntityData.NAMETAG, this.username);
+            needsUpdate = !newDisplayName.equals(this.nametag);
+            this.nametag = newDisplayName;
         } else {
-            needsUpdate = false;
+            // The name has reset, if it was previously something else
+            needsUpdate = !this.nametag.equals(this.username);
+            this.nametag = this.username;
         }
 
         if (needsUpdate) {
-            // Update the metadata as it won't be updated later
-            SetEntityDataPacket packet = new SetEntityDataPacket();
-            packet.getMetadata().put(EntityData.NAMETAG, newDisplayName);
-            packet.setRuntimeEntityId(geyserId);
-            session.sendUpstreamPacket(packet);
+            dirtyMetadata.put(EntityData.NAMETAG, this.nametag);
         }
     }
 

core/src/main/java/org/geysermc/geyser/scoreboard/Scoreboard.java

@@ -30,6 +30,7 @@ import com.nukkitx.protocol.bedrock.data.ScoreInfo;
 import com.nukkitx.protocol.bedrock.packet.RemoveObjectivePacket;
 import com.nukkitx.protocol.bedrock.packet.SetDisplayObjectivePacket;
 import com.nukkitx.protocol.bedrock.packet.SetScorePacket;
+import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
 import lombok.Getter;
 import org.geysermc.geyser.GeyserImpl;
 import org.geysermc.geyser.GeyserLogger;
@@ -56,6 +57,13 @@ public final class Scoreboard {
     @Getter
     private final Map<ScoreboardPosition, Objective> objectiveSlots = new EnumMap<>(ScoreboardPosition.class);
     private final Map<String, Team> teams = new ConcurrentHashMap<>(); // updated on multiple threads
+    /**
+     * Required to preserve vanilla behavior, which also uses a map.
+     * Otherwise, for example, if TAB has a team for a player and vanilla has a team, "race conditions" that do not
+     * match vanilla could occur.
+     */
+    @Getter
+    private final Map<String, Team> playerToTeam = new Object2ObjectOpenHashMap<>();
 
     private int lastAddScoreCount = 0;
     private int lastRemoveScoreCount = 0;
@@ -333,12 +341,7 @@ public final class Scoreboard {
     }
 
     public Team getTeamFor(String entity) {
-        for (Team team : teams.values()) {
-            if (team.hasEntity(entity)) {
-                return team;
-            }
-        }
-        return null;
+        return playerToTeam.get(entity);
     }
 
     public void removeTeam(String teamName) {
@@ -380,7 +383,8 @@ public final class Scoreboard {
             for (Entity entity : session.getEntityCache().getEntities().values()) {
                 // This more complex logic is for the future to iterate over all entities, not just players
                 if (entity instanceof PlayerEntity player && names.remove(player.getUsername())) {
-                    player.updateDisplayName(team, true);
+                    player.updateDisplayName(team);
+                    player.updateBedrockMetadata();
                     if (names.isEmpty()) {
                         break;
                     }
@@ -396,7 +400,8 @@ public final class Scoreboard {
         for (Entity entity : session.getEntityCache().getEntities().values()) {
             if (entity instanceof PlayerEntity player) {
                 Team playerTeam = session.getWorldCache().getScoreboard().getTeamFor(player.getUsername());
-                player.updateDisplayName(playerTeam, true);
+                player.updateDisplayName(playerTeam);
+                player.updateBedrockMetadata();
             }
         }
     }

core/src/main/java/org/geysermc/geyser/scoreboard/Team.java

@@ -65,6 +65,7 @@ public final class Team {
             if (entities.add(name)) {
                 added.add(name);
             }
+            scoreboard.getPlayerToTeam().put(name, this);
         }
 
         if (added.isEmpty()) {
@@ -93,6 +94,7 @@ public final class Team {
             if (entities.remove(name)) {
                 removed.add(name);
             }
+            scoreboard.getPlayerToTeam().remove(name, this);
         }
         return removed;
     }