From 4127eea4014625d8e1479da1d84d30f3a9691866 Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Tue, 4 Aug 2020 12:44:07 +0200
Subject: [PATCH 1/6] Support for all living entities / Added team builder /
 Comments

---
 .../minestom/server/entity/LivingEntity.java  |  39 ++
 .../net/minestom/server/entity/Player.java    |  31 +-
 .../packet/server/play/TeamsPacket.java       | 139 +++++-
 .../net/minestom/server/scoreboard/Team.java  | 443 ++++++++++++++----
 .../server/scoreboard/TeamBuilder.java        | 347 ++++++++++++++
 .../server/scoreboard/TeamManager.java        | 135 +++++-
 6 files changed, 1016 insertions(+), 118 deletions(-)
 create mode 100644 src/main/java/net/minestom/server/scoreboard/TeamBuilder.java

diff --git a/src/main/java/net/minestom/server/entity/LivingEntity.java b/src/main/java/net/minestom/server/entity/LivingEntity.java
index bafc7ba4c..810934236 100644
--- a/src/main/java/net/minestom/server/entity/LivingEntity.java
+++ b/src/main/java/net/minestom/server/entity/LivingEntity.java
@@ -13,6 +13,7 @@ import net.minestom.server.item.ItemStack;
 import net.minestom.server.network.packet.PacketWriter;
 import net.minestom.server.network.packet.server.play.*;
 import net.minestom.server.network.player.PlayerConnection;
+import net.minestom.server.scoreboard.Team;
 import net.minestom.server.sound.Sound;
 import net.minestom.server.sound.SoundCategory;
 import net.minestom.server.utils.Position;
@@ -54,6 +55,8 @@ public abstract class LivingEntity extends Entity implements EquipmentHandler {
      */
     private long fireDamagePeriod = 1000L;
 
+    private Team team;
+
     public LivingEntity(EntityType entityType, Position spawnPosition) {
         super(entityType, spawnPosition);
         setupAttributes();
@@ -505,4 +508,40 @@ public abstract class LivingEntity extends Entity implements EquipmentHandler {
         fireDamagePeriod = timeUnit.toMilliseconds(fireDamagePeriod);
         this.fireDamagePeriod = fireDamagePeriod;
     }
+
+    /**
+     * Change the {@link Team} for the entity
+     *
+     * @param team The new team
+     */
+    public void setTeam(Team team) {
+        if (this.team == team) return;
+
+        String member;
+
+        if (this instanceof Player) {
+            Player player = (Player) this;
+            member = player.getUsername();
+        } else {
+            member = this.uuid.toString();
+        }
+
+        if (this.team != null) {
+            this.team.removeMember(member);
+        }
+
+        this.team = team;
+        if (team != null) {
+            team.addMember(member);
+        }
+    }
+
+    /**
+     * Gets the {@link Team} of the entity
+     *
+     * @return the {@link Team}
+     */
+    public Team getTeam() {
+        return team;
+    }
 }
diff --git a/src/main/java/net/minestom/server/entity/Player.java b/src/main/java/net/minestom/server/entity/Player.java
index 6351b80be..1137ef94c 100644
--- a/src/main/java/net/minestom/server/entity/Player.java
+++ b/src/main/java/net/minestom/server/entity/Player.java
@@ -109,7 +109,6 @@ public class Player extends LivingEntity implements CommandSender {
     private int blockBreakTime;
 
     private Set<BossBar> bossBars = new CopyOnWriteArraySet<>();
-    private Team team;
     private BelowNameScoreboard belowNameScoreboard;
 
     /**
@@ -527,8 +526,8 @@ public class Player extends LivingEntity implements CommandSender {
         viewerConnection.sendPacket(getRemovePlayerToList());
 
         // Team
-        if (team != null && team.getPlayers().size() == 1) // If team only contains "this" player
-            viewerConnection.sendPacket(team.createTeamDestructionPacket());
+        if (this.getTeam() != null && this.getTeam().getMembers().size() == 1) // If team only contains "this" player
+            viewerConnection.sendPacket(this.getTeam().createTeamDestructionPacket());
         return result;
     }
 
@@ -1371,21 +1370,6 @@ public class Player extends LivingEntity implements CommandSender {
         return heldSlot;
     }
 
-    public void setTeam(Team team) {
-        if (this.team == team)
-            return;
-
-        if (this.team != null) {
-            this.team.removePlayer(this);
-        }
-
-        this.team = team;
-        if (team != null) {
-            team.addPlayer(this);
-            sendPacketToViewers(team.getTeamsCreationPacket()); // FIXME: only if viewer hasn't already register this team
-        }
-    }
-
     public void setBelowNameScoreboard(BelowNameScoreboard belowNameScoreboard) {
         if (this.belowNameScoreboard == belowNameScoreboard)
             return;
@@ -1402,6 +1386,13 @@ public class Player extends LivingEntity implements CommandSender {
         }
     }
 
+    @Override
+    public void setTeam(Team team) {
+        super.setTeam(team);
+        if(team != null)
+            getPlayerConnection().sendPacket(team.getTeamsCreationPacket());
+    }
+
     /**
      * Used to get the {@link CustomBlock} that the player is currently mining
      *
@@ -2005,8 +1996,8 @@ public class Player extends LivingEntity implements CommandSender {
         }
 
         // Team
-        if (team != null)
-            connection.sendPacket(team.getTeamsCreationPacket());
+        if (this.getTeam() != null)
+            connection.sendPacket(this.getTeam().getTeamsCreationPacket());
 
         EntityHeadLookPacket entityHeadLookPacket = new EntityHeadLookPacket();
         entityHeadLookPacket.entityId = getEntityId();
diff --git a/src/main/java/net/minestom/server/network/packet/server/play/TeamsPacket.java b/src/main/java/net/minestom/server/network/packet/server/play/TeamsPacket.java
index 2c1d08a00..7ece592d9 100644
--- a/src/main/java/net/minestom/server/network/packet/server/play/TeamsPacket.java
+++ b/src/main/java/net/minestom/server/network/packet/server/play/TeamsPacket.java
@@ -4,35 +4,73 @@ import net.minestom.server.network.packet.PacketWriter;
 import net.minestom.server.network.packet.server.ServerPacket;
 import net.minestom.server.network.packet.server.ServerPacketIdentifier;
 
+/**
+ * The packet creates or updates teams
+ */
 public class TeamsPacket implements ServerPacket {
 
+    /**
+     * The registry name of the team
+     */
     public String teamName;
+    /**
+     * The action of the packet
+     */
     public Action action;
 
+    /**
+     * The display name for the team
+     */
     public String teamDisplayName;
+    /**
+     * The friendly flags to
+     */
     public byte friendlyFlags;
+    /**
+     * Visibility state for the name tag
+     */
     public NameTagVisibility nameTagVisibility;
+    /**
+     * Rule for the collision
+     */
     public CollisionRule collisionRule;
+    /**
+     * The color of the team
+     */
     public int teamColor;
+    /**
+     * The prefix of the team
+     */
     public String teamPrefix;
+    /**
+     * The suffix of the team
+     */
     public String teamSuffix;
+    /**
+     * An array with all entities in the team
+     */
     public String[] entities;
 
+    /**
+     * Writes data into the {@link PacketWriter}
+     *
+     * @param writer The writer to writes
+     */
     @Override
     public void write(PacketWriter writer) {
-        writer.writeSizedString(teamName);
-        writer.writeByte((byte) action.ordinal());
+        writer.writeSizedString(this.teamName);
+        writer.writeByte((byte) this.action.ordinal());
 
         switch (action) {
             case CREATE_TEAM:
             case UPDATE_TEAM_INFO:
-                writer.writeSizedString(teamDisplayName);
-                writer.writeByte(friendlyFlags);
-                writer.writeSizedString(nameTagVisibility.getIdentifier());
-                writer.writeSizedString(collisionRule.getIdentifier());
-                writer.writeVarInt(teamColor);
-                writer.writeSizedString(teamPrefix);
-                writer.writeSizedString(teamSuffix);
+                writer.writeSizedString(this.teamDisplayName);
+                writer.writeByte(this.friendlyFlags);
+                writer.writeSizedString(this.nameTagVisibility.getIdentifier());
+                writer.writeSizedString(this.collisionRule.getIdentifier());
+                writer.writeVarInt(this.teamColor);
+                writer.writeSizedString(this.teamPrefix);
+                writer.writeSizedString(this.teamSuffix);
                 break;
             case REMOVE_TEAM:
 
@@ -45,48 +83,127 @@ public class TeamsPacket implements ServerPacket {
 
     }
 
+    /**
+     * Gets the identifier of the packet
+     *
+     * @return the identifier
+     */
     @Override
     public int getId() {
         return ServerPacketIdentifier.TEAMS;
     }
 
+    /**
+     * An enumeration which representing all actions for the packet
+     */
     public enum Action {
+        /**
+         * An action to create a new team
+         */
         CREATE_TEAM,
+        /**
+         * An action to remove a team
+         */
         REMOVE_TEAM,
+        /**
+         * An action to update the team information
+         */
         UPDATE_TEAM_INFO,
+        /**
+         * An action to add player to the team
+         */
         ADD_PLAYERS_TEAM,
+        /**
+         * An action to remove player from the team
+         */
         REMOVE_PLAYERS_TEAM
     }
 
+    /**
+     * An enumeration which representing all visibility states for the name tags
+     */
     public enum NameTagVisibility {
+        /**
+         * The name tag is visible
+         */
         ALWAYS("always"),
+        /**
+         * Hides the name tag for other teams
+         */
         HIDE_FOR_OTHER_TEAMS("hideForOtherTeams"),
+        /**
+         * Hides the name tag for the own team
+         */
         HIDE_FOR_OWN_TEAM("hideForOwnTeam"),
+        /**
+         * The name tag is invisible
+         */
         NEVER("never");
 
-        private String identifier;
+        /**
+         * The identifier for the client
+         */
+        private final String identifier;
 
+        /**
+         * Default constructor
+         *
+         * @param identifier The client identifier
+         */
         NameTagVisibility(String identifier) {
             this.identifier = identifier;
         }
 
+        /**
+         * Gets the client identifier
+         *
+         * @return the identifier
+         */
         public String getIdentifier() {
             return identifier;
         }
     }
 
+    /**
+     * An enumeration which representing all rules for the collision
+     */
     public enum CollisionRule {
+        /**
+         * Can push all objects and can be pushed by all objects
+         */
         ALWAYS("always"),
+        /**
+         * Can push objects of other teams, but teammates cannot
+         */
         PUSH_OTHER_TEAMS("pushOtherTeams"),
+        /**
+         * Can only push objects of the same team
+         */
         PUSH_OWN_TEAM("pushOwnTeam"),
+        /**
+         * Cannot push an object, but neither can they be pushed
+         */
         NEVER("never");
 
-        private String identifier;
+        /**
+         * The identifier for the client
+         */
+        private final String identifier;
 
+        /**
+         * Default constructor
+         *
+         * @param identifier The identifier for the client
+         */
         CollisionRule(String identifier) {
             this.identifier = identifier;
         }
 
+        /**
+         * Gets the identifier of the rule
+         *
+         * @return the identifier
+         */
         public String getIdentifier() {
             return identifier;
         }
diff --git a/src/main/java/net/minestom/server/scoreboard/Team.java b/src/main/java/net/minestom/server/scoreboard/Team.java
index cc322a25b..a84ab1e2c 100644
--- a/src/main/java/net/minestom/server/scoreboard/Team.java
+++ b/src/main/java/net/minestom/server/scoreboard/Team.java
@@ -1,142 +1,350 @@
 package net.minestom.server.scoreboard;
 
 import io.netty.buffer.ByteBuf;
+import net.minestom.server.MinecraftServer;
 import net.minestom.server.chat.ChatColor;
 import net.minestom.server.chat.ColoredText;
+import net.minestom.server.entity.LivingEntity;
 import net.minestom.server.entity.Player;
+import net.minestom.server.network.PacketWriterUtils;
 import net.minestom.server.network.packet.server.play.TeamsPacket;
+import net.minestom.server.network.packet.server.play.TeamsPacket.CollisionRule;
+import net.minestom.server.network.packet.server.play.TeamsPacket.NameTagVisibility;
 import net.minestom.server.utils.PacketUtils;
 
 import java.util.Collections;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
+/**
+ * This object represents a team on a scoreboard that has a common display theme and other properties.
+ */
 public class Team {
 
-    private String teamName;
-    private ColoredText teamDisplayName = ColoredText.of("");
-    private byte friendlyFlags = 0x00;
-    private TeamsPacket.NameTagVisibility nameTagVisibility = TeamsPacket.NameTagVisibility.ALWAYS;
-    private TeamsPacket.CollisionRule collisionRule = TeamsPacket.CollisionRule.NEVER;
-    private ChatColor teamColor = ChatColor.WHITE;
+    /**
+     * A collection of all registered entities who are on the team
+     */
+    private final Set<String> members;
+    /**
+     * Creation packet for the team to create
+     */
+    private final TeamsPacket teamsCreationPacket;
+    /**
+     * A byte buf to destroy the team
+     */
+    private final ByteBuf teamsDestroyPacket;
 
-    private ColoredText prefix = ColoredText.of("");
-    private ColoredText suffix = ColoredText.of("");
+    /**
+     * The registry name of the team
+     */
+    private final String teamName;
+    /**
+     * The display name of the team
+     */
+    private ColoredText teamDisplayName;
+    /**
+     * A BitMask
+     */
+    private byte friendlyFlags;
+    /**
+     * The visibility of the team
+     */
+    private NameTagVisibility nameTagVisibility;
+    /**
+     * The collision rule of the team
+     */
+    private CollisionRule collisionRule;
 
-    private String[] entities = new String[0];
-    private Set<Player> players = new CopyOnWriteArraySet<>();
+    /**
+     * Used to color the name of players on the team <br>
+     * The color of a team defines how the names of the team members are visualized
+     */
+    private ChatColor teamColor;
 
-    private TeamsPacket teamsCreationPacket;
+    /**
+     * Shown before the names of the players who belong to this team
+     */
+    private ColoredText prefix;
+    /**
+     * Shown after the names of the player who belong to this team
+     */
+    private ColoredText suffix;
 
-    private ByteBuf teamsDestroyPacket;
+    /**
+     * Identifiers for the entities in this team
+     */
+    private String[] entities;
 
+    /**
+     * Default constructor to creates a team
+     *
+     * @param teamName The registry name for the team
+     */
     protected Team(String teamName) {
         this.teamName = teamName;
 
-        teamsCreationPacket = new TeamsPacket();
-        teamsCreationPacket.teamName = teamName;
-        teamsCreationPacket.action = TeamsPacket.Action.CREATE_TEAM;
-        teamsCreationPacket.teamDisplayName = teamDisplayName.toString();
-        teamsCreationPacket.friendlyFlags = friendlyFlags;
-        teamsCreationPacket.nameTagVisibility = nameTagVisibility;
-        teamsCreationPacket.collisionRule = collisionRule;
-        teamsCreationPacket.teamColor = teamColor.getId();
-        teamsCreationPacket.teamPrefix = prefix.toString();
-        teamsCreationPacket.teamSuffix = suffix.toString();
-        teamsCreationPacket.entities = entities;
+        this.teamDisplayName = ColoredText.of("");
+        this.friendlyFlags = 0x00;
+        this.nameTagVisibility = NameTagVisibility.ALWAYS;
+        this.collisionRule = CollisionRule.ALWAYS;
 
-        TeamsPacket destroyPacket = new TeamsPacket();
-        destroyPacket.teamName = teamName;
-        destroyPacket.action = TeamsPacket.Action.REMOVE_TEAM;
-        teamsDestroyPacket = PacketUtils.writePacket(destroyPacket); // Directly write packet since it will not change
+        this.teamColor = ChatColor.WHITE;
+        this.prefix = ColoredText.of("");
+        this.suffix = ColoredText.of("");
+
+        this.entities = new String[0];
+        this.members = new CopyOnWriteArraySet<>();
+
+        // Initializes creation packet
+        this.teamsCreationPacket = new TeamsPacket();
+        this.teamsCreationPacket.teamName = teamName;
+        this.teamsCreationPacket.action = TeamsPacket.Action.CREATE_TEAM;
+        this.teamsCreationPacket.teamDisplayName = this.teamDisplayName.toString();
+        this.teamsCreationPacket.friendlyFlags = this.friendlyFlags;
+        this.teamsCreationPacket.nameTagVisibility = this.nameTagVisibility;
+        this.teamsCreationPacket.collisionRule = this.collisionRule;
+        this.teamsCreationPacket.teamColor = this.teamColor.getId();
+        this.teamsCreationPacket.teamPrefix = this.prefix.toString();
+        this.teamsCreationPacket.teamSuffix = this.suffix.toString();
+        this.teamsCreationPacket.entities = this.entities;
+
+        // Directly write packet since it will not change
+        this.teamsDestroyPacket = PacketUtils.writePacket(this.createTeamDestructionPacket());
     }
 
-    public void addPlayer(Player player) {
-        final String newElement = player.getUsername();
+    /**
+     * Adds a member to the {@link Team}
+     * <br>
+     * This member can be a {@link Player} or an {@link LivingEntity}
+     *
+     * @param member The member to be added
+     */
+    public void addMember(String member) {
+        final String[] entitiesCache = new String[this.entities.length + 1];
+        System.arraycopy(this.entities, 0, entitiesCache, 0, this.entities.length);
+        entitiesCache[this.entities.length] = member;
+        this.entities = entitiesCache;
+        this.teamsCreationPacket.entities = this.entities;
 
-        TeamsPacket addPlayerPacket = new TeamsPacket();
-        addPlayerPacket.teamName = teamName;
+        // Adds a new member to the team
+        this.members.add(member);
+
+        // Initializes add player packet
+        final TeamsPacket addPlayerPacket = new TeamsPacket();
+        addPlayerPacket.teamName = this.teamName;
         addPlayerPacket.action = TeamsPacket.Action.ADD_PLAYERS_TEAM;
-        addPlayerPacket.entities = new String[]{newElement};
-        for (Player p : players) {
-            p.getPlayerConnection().sendPacket(addPlayerPacket);
-        }
-
-        String[] entitiesCache = new String[entities.length + 1];
-        System.arraycopy(entities, 0, entitiesCache, 0, entities.length);
-        entitiesCache[entities.length] = newElement;
-        this.entities = entitiesCache;
-        this.teamsCreationPacket.entities = entities;
-
-        this.players.add(player);
-        player.getPlayerConnection().sendPacket(teamsCreationPacket);
+        addPlayerPacket.entities = new String[]{member};
+        // Sends to all online players the add player packet
+        PacketWriterUtils.writeAndSend(MinecraftServer.getConnectionManager().getOnlinePlayers(), addPlayerPacket);
     }
 
-    public void removePlayer(Player player) {
-        TeamsPacket removePlayerPacket = new TeamsPacket();
-        removePlayerPacket.teamName = teamName;
+    /**
+     * Removes a member from the {@link Team}
+     *
+     * @param member The member to be removed
+     */
+    public void removeMember(String member) {
+        // Initializes remove player packet
+        final TeamsPacket removePlayerPacket = new TeamsPacket();
+        removePlayerPacket.teamName = this.teamName;
         removePlayerPacket.action = TeamsPacket.Action.REMOVE_PLAYERS_TEAM;
-        removePlayerPacket.entities = new String[]{player.getUsername()};
-        for (Player p : players) {
-            p.getPlayerConnection().sendPacket(removePlayerPacket);
-        }
+        removePlayerPacket.entities = new String[]{member};
+        // Sends to all online player teh remove player packet
+        PacketWriterUtils.writeAndSend(MinecraftServer.getConnectionManager().getOnlinePlayers(), removePlayerPacket);
 
-        this.players.remove(player);
-        player.getPlayerConnection().sendPacket(teamsDestroyPacket, true); // TODO do not destroy, simply remove the player from the team
+        // Removes the player from the
+        this.members.remove(member);
 
-        String[] entitiesCache = new String[entities.length - 1];
+        final String[] entitiesCache = new String[this.entities.length - 1];
         int count = 0;
-        for (Player p : players) {
-            entitiesCache[count++] = p.getUsername();
+        for (String teamMember : this.members) {
+            entitiesCache[count++] = teamMember;
         }
         this.entities = entitiesCache;
-        this.teamsCreationPacket.entities = entities;
+        this.teamsCreationPacket.entities = this.entities;
     }
 
+    /**
+     * Change the display name of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param teamDisplayName The new display name
+     */
     public void setTeamDisplayName(ColoredText teamDisplayName) {
         this.teamDisplayName = teamDisplayName;
         this.teamsCreationPacket.teamDisplayName = teamDisplayName.toString();
+    }
+
+    /**
+     * Change the display name of the team and sends an update packet
+     *
+     * @param teamDisplayName The new display name
+     */
+    public void updateTeamDisplayName(ColoredText teamDisplayName) {
+        this.setTeamDisplayName(teamDisplayName);
         sendUpdatePacket();
     }
 
-    public void setNameTagVisibility(TeamsPacket.NameTagVisibility nameTagVisibility) {
-        this.nameTagVisibility = nameTagVisibility;
-        this.teamsCreationPacket.nameTagVisibility = nameTagVisibility;
+    /**
+     * Change the {@link NameTagVisibility} of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param visibility The new tag visibility
+     */
+    public void setNameTagVisibility(NameTagVisibility visibility) {
+        this.nameTagVisibility = visibility;
+        this.teamsCreationPacket.nameTagVisibility = visibility;
+    }
+
+    /**
+     * Change the {@link NameTagVisibility} of the team and sends an update packet
+     *
+     * @param nameTagVisibility The new tag visibility
+     */
+    public void updateNameTagVisibility(NameTagVisibility nameTagVisibility) {
+        this.setNameTagVisibility(nameTagVisibility);
         sendUpdatePacket();
     }
 
-    public void setCollisionRule(TeamsPacket.CollisionRule collisionRule) {
-        this.collisionRule = collisionRule;
-        this.teamsCreationPacket.collisionRule = collisionRule;
+    /**
+     * Change the {@link CollisionRule} of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param rule The new rule
+     */
+    public void setCollisionRule(CollisionRule rule) {
+        this.collisionRule = rule;
+        this.teamsCreationPacket.collisionRule = rule;
+    }
+
+    /**
+     * Change the collision rule of the team and sends an update packet
+     *
+     * @param collisionRule The new collision rule
+     */
+    public void updateCollisionRule(CollisionRule collisionRule) {
+        this.setCollisionRule(collisionRule);
         sendUpdatePacket();
     }
 
-    public void setTeamColor(ChatColor teamColor) {
-        this.teamColor = teamColor;
-        this.teamsCreationPacket.teamColor = teamColor.getId();
+    /**
+     * Change the color of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param color The new team color
+     */
+    public void setTeamColor(ChatColor color) {
+        this.teamColor = color;
+        this.teamsCreationPacket.teamColor = color.getId();
+    }
+
+    /**
+     * Change the color of the team and sends an update packet
+     *
+     * @param teamColor The new team color
+     */
+    public void updateTeamColor(ChatColor teamColor) {
+        this.setTeamColor(teamColor);
         sendUpdatePacket();
     }
 
+    /**
+     * Change the prefix of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param prefix The new prefix
+     */
     public void setPrefix(ColoredText prefix) {
         this.prefix = prefix;
         this.teamsCreationPacket.teamPrefix = prefix.toString();
+    }
+
+    /**
+     * Change the prefix of the team and sends an update packet
+     *
+     * @param prefix The new prefix
+     */
+    public void updatePrefix(ColoredText prefix) {
+        this.setPrefix(prefix);
         sendUpdatePacket();
     }
 
+    /**
+     * Change the suffix of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param suffix The new suffix
+     */
     public void setSuffix(ColoredText suffix) {
         this.suffix = suffix;
         this.teamsCreationPacket.teamSuffix = suffix.toString();
+    }
+
+    /**
+     * Change the suffix of the team and sends an update packet
+     *
+     * @param suffix The new suffix
+     */
+    public void updateSuffix(ColoredText suffix) {
+        this.setSuffix(suffix);
         sendUpdatePacket();
     }
 
+    /**
+     * Change the friendly flags of the team
+     * <br><br>
+     * <b>Warning:</b> This is only changed on the <b>server side</b>
+     *
+     * @param flag The new friendly flag
+     */
+    public void setFriendlyFlags(byte flag) {
+        this.friendlyFlags = flag;
+        this.teamsCreationPacket.friendlyFlags = flag;
+    }
+
+    /**
+     * Change the friendly flags of the team and sends an update packet
+     *
+     * @param flag The new friendly flag
+     */
+    public void updateFriendlyFlags(byte flag) {
+        this.setFriendlyFlags(flag);
+        this.sendUpdatePacket();
+    }
+
+    /**
+     * Gets the registry name of the team
+     *
+     * @return the registry name
+     */
     public String getTeamName() {
         return teamName;
     }
 
+    /**
+     * Gets the creation packet to add a team
+     *
+     * @return the packet to add the team
+     */
     public TeamsPacket getTeamsCreationPacket() {
         return teamsCreationPacket;
     }
 
+    public ByteBuf getTeamsDestroyPacket() {
+        return teamsDestroyPacket;
+    }
+
+    /**
+     * Creates an destruction packet to remove the team
+     *
+     * @return the packet to remove the team
+     */
     public TeamsPacket createTeamDestructionPacket() {
         TeamsPacket teamsPacket = new TeamsPacket();
         teamsPacket.teamName = teamName;
@@ -144,22 +352,99 @@ public class Team {
         return teamsPacket;
     }
 
-    public Set<Player> getPlayers() {
-        return Collections.unmodifiableSet(players);
+    /**
+     * Obtains an unmodifiable {@link Set} of registered players who are on the team
+     *
+     * @return an unmodifiable {@link Set} of registered players
+     */
+    public Set<String> getMembers() {
+        return Collections.unmodifiableSet(members);
     }
 
-    private void sendUpdatePacket() {
-        TeamsPacket updatePacket = new TeamsPacket();
-        updatePacket.teamName = teamName;
+    /**
+     * Gets the display name of the team
+     *
+     * @return the display name
+     */
+    public ColoredText getTeamDisplayName() {
+        return teamDisplayName;
+    }
+
+    /**
+     * Gets the friendly flags of the team
+     *
+     * @return the friendly flags
+     */
+    public byte getFriendlyFlags() {
+        return friendlyFlags;
+    }
+
+    /**
+     * Gets the tag visibility of the team
+     *
+     * @return the tag visibility
+     */
+    public NameTagVisibility getNameTagVisibility() {
+        return nameTagVisibility;
+    }
+
+    /**
+     * Gets the collision rule of the team
+     *
+     * @return the collision rule
+     */
+    public CollisionRule getCollisionRule() {
+        return collisionRule;
+    }
+
+    /**
+     * Gets the color of the team
+     *
+     * @return the team color
+     */
+    public ChatColor getTeamColor() {
+        return teamColor;
+    }
+
+    /**
+     * Gets the prefix of the team
+     *
+     * @return the team prefix
+     */
+    public ColoredText getPrefix() {
+        return prefix;
+    }
+
+    /**
+     * Gets the suffix of the team
+     *
+     * @return the suffix team
+     */
+    public ColoredText getSuffix() {
+        return suffix;
+    }
+
+    public String[] getEntities() {
+        return entities;
+    }
+
+    /**
+     * Sends an {@link TeamsPacket.Action#UPDATE_TEAM_INFO} packet
+     */
+    public void sendUpdatePacket() {
+        final TeamsPacket updatePacket = new TeamsPacket();
+        updatePacket.teamName = this.teamName;
         updatePacket.action = TeamsPacket.Action.UPDATE_TEAM_INFO;
-        updatePacket.teamDisplayName = teamDisplayName.toString();
-        updatePacket.friendlyFlags = friendlyFlags;
-        updatePacket.nameTagVisibility = nameTagVisibility;
-        updatePacket.collisionRule = collisionRule;
-        updatePacket.teamColor = teamColor.getId();
-        updatePacket.teamPrefix = prefix.toString();
-        updatePacket.teamSuffix = suffix.toString();
+        updatePacket.teamDisplayName = this.teamDisplayName.toString();
+        updatePacket.friendlyFlags = this.friendlyFlags;
+        updatePacket.nameTagVisibility = this.nameTagVisibility;
+        updatePacket.collisionRule = this.collisionRule;
+        updatePacket.teamColor = this.teamColor.getId();
+        updatePacket.teamPrefix = this.prefix.toString();
+        updatePacket.teamSuffix = this.suffix.toString();
         ByteBuf buffer = PacketUtils.writePacket(updatePacket);
-        players.forEach(p -> p.getPlayerConnection().sendPacket(buffer, true));
+        for (Player onlinePlayer : MinecraftServer.getConnectionManager().getOnlinePlayers()) {
+            onlinePlayer.getPlayerConnection().sendPacket(buffer, true);
+        }
     }
 }
diff --git a/src/main/java/net/minestom/server/scoreboard/TeamBuilder.java b/src/main/java/net/minestom/server/scoreboard/TeamBuilder.java
new file mode 100644
index 000000000..d27920413
--- /dev/null
+++ b/src/main/java/net/minestom/server/scoreboard/TeamBuilder.java
@@ -0,0 +1,347 @@
+package net.minestom.server.scoreboard;
+
+import net.minestom.server.chat.ChatColor;
+import net.minestom.server.chat.ColoredText;
+import net.minestom.server.network.packet.server.play.TeamsPacket.CollisionRule;
+import net.minestom.server.network.packet.server.play.TeamsPacket.NameTagVisibility;
+
+/**
+ * A builder which represents a fluent Object to built teams
+ */
+public class TeamBuilder {
+
+    /**
+     * The management for the teams
+     */
+    private final TeamManager teamManager;
+    /**
+     * The team to create
+     */
+    private final Team team;
+    /**
+     * True, if it should send an update packet
+     */
+    private boolean updateTeam;
+
+    /**
+     * Creates an team builder
+     *
+     * @param name        The name of the new team
+     * @param teamManager The manager for the team
+     */
+    public TeamBuilder(String name, TeamManager teamManager) {
+        this(teamManager.exists(name) ? teamManager.getTeam(name) : new Team(name), teamManager);
+    }
+
+    /**
+     * Creates an team builder
+     *
+     * @param team        The new team
+     * @param teamManager The manager for the team
+     */
+    private TeamBuilder(Team team, TeamManager teamManager) {
+        this.team = team;
+        this.teamManager = teamManager;
+        this.updateTeam = false;
+    }
+
+    /**
+     * Updates the prefix of the {@link Team}
+     *
+     * @param prefix The new prefix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updatePrefix(String prefix) {
+        return this.updatePrefix(ColoredText.of(prefix));
+    }
+
+    /**
+     * Updates the prefix of the {@link Team}
+     *
+     * @param prefix The new prefix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updatePrefix(ColoredText prefix) {
+        this.team.updatePrefix(prefix);
+        return this;
+    }
+
+    /**
+     * Updates the color of the {@link Team}
+     *
+     * @param color The new color
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateTeamColor(ChatColor color) {
+        this.team.updateTeamColor(color);
+        return this;
+    }
+
+    /**
+     * Updates the suffix of the {@link Team}
+     *
+     * @param suffix The new suffix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateSuffix(String suffix) {
+        return updateSuffix(ColoredText.of(suffix));
+    }
+
+    /**
+     * Updates the suffix of the {@link Team}
+     *
+     * @param suffix The new suffix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateSuffix(ColoredText suffix) {
+        this.team.updateSuffix(suffix);
+        return this;
+    }
+
+    /**
+     * Updates the display name of the {@link Team}
+     *
+     * @param displayName The new display name
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateTeamDisplayName(String displayName) {
+        return this.updateTeamDisplayName(ColoredText.of(displayName));
+    }
+
+    /**
+     * Updates the display name of the {@link Team}
+     *
+     * @param displayName The new display name
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateTeamDisplayName(ColoredText displayName) {
+        this.team.updateTeamDisplayName(displayName);
+        return this;
+    }
+
+    /**
+     * Updates the {@link CollisionRule} of the {@link Team}
+     *
+     * @param rule The new rule
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateCollisionRule(CollisionRule rule) {
+        this.team.updateCollisionRule(rule);
+        return this;
+    }
+
+    /**
+     * Updates the {@link NameTagVisibility} of the {@link Team}
+     *
+     * @param visibility The new tag visibility
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateNameTagVisibility(NameTagVisibility visibility) {
+        this.team.updateNameTagVisibility(visibility);
+        return this;
+    }
+
+    /**
+     * Updates the friendly flags of the {@link Team}
+     *
+     * @param flag The new friendly flag
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateFriendlyFlags(byte flag) {
+        this.team.updateFriendlyFlags(flag);
+        return this;
+    }
+
+    /**
+     * Updates the friendly flags for allow friendly fire
+     *
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateAllowFriendlyFire() {
+        return this.updateFriendlyFlags((byte) 0x01);
+    }
+
+    /**
+     * Updates the friendly flags to sees invisible players of own team
+     *
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateSeeInvisiblePlayers() {
+        return this.updateFriendlyFlags((byte) 0x01);
+    }
+
+    /**
+     * Change the prefix of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param prefix The new prefix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder prefix(String prefix) {
+        return this.prefix(ColoredText.of(prefix));
+    }
+
+    /**
+     * Change the prefix of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param prefix The new prefix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder prefix(ColoredText prefix) {
+        this.team.setPrefix(prefix);
+        return this;
+    }
+
+    /**
+     * Change the suffix of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param suffix The new suffix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder suffix(String suffix) {
+        this.team.setSuffix(ColoredText.of(suffix));
+        return this;
+    }
+
+    /**
+     * Change the suffix of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param suffix The new suffix
+     * @return this builder, for chaining
+     */
+    public TeamBuilder suffix(ColoredText suffix) {
+        this.team.setSuffix(suffix);
+        return this;
+    }
+
+    /**
+     * Change the color of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param color The new team color
+     * @return this builder, for chaining
+     */
+    public TeamBuilder teamColor(ChatColor color) {
+        this.team.setTeamColor(color);
+        return this;
+    }
+
+    /**
+     * Change the display name of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param displayName The new display name
+     * @return this builder, for chaining
+     */
+    public TeamBuilder teamDisplayName(String displayName) {
+        return this.teamDisplayName(ColoredText.of(displayName));
+    }
+
+    /**
+     * Change the display name of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param displayName The new display name
+     * @return this builder, for chaining
+     */
+    public TeamBuilder teamDisplayName(ColoredText displayName) {
+        this.team.setTeamDisplayName(displayName);
+        return this;
+    }
+
+    /**
+     * Change the {@link CollisionRule} of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param rule The new rule
+     * @return this builder, for chaining
+     */
+    public TeamBuilder collisionRule(CollisionRule rule) {
+        this.team.setCollisionRule(rule);
+        return this;
+    }
+
+    /**
+     * Change the {@link NameTagVisibility} of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param visibility The new tag visibility
+     * @return this builder, for chaining
+     */
+    public TeamBuilder nameTagVisibility(NameTagVisibility visibility) {
+        this.team.setNameTagVisibility(visibility);
+        return this;
+    }
+
+    /**
+     * Change the friendly flags of the {@link Team} without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @param flag The new flag
+     * @return this builder, for chaining
+     */
+    public TeamBuilder friendlyFlags(byte flag) {
+        this.team.setFriendlyFlags(flag);
+        return this;
+    }
+
+    /**
+     * Change the friendly flags for allow friendly fire without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @return this builder, for chaining
+     */
+    public TeamBuilder allowFriendlyFire() {
+        return this.friendlyFlags((byte) 0x01);
+    }
+
+    /**
+     * Change the friendly flags to sees invisible players of own team without an update packet
+     * <br><br>
+     * <b>Warning: </b> If you do not call {@link #updateTeamPacket()}, this is only changed of the <b>server side</b>
+     *
+     * @return this builder, for chaining
+     */
+    public TeamBuilder seeInvisiblePlayers() {
+        return this.friendlyFlags((byte) 0x01);
+    }
+
+    /**
+     * Allows to send an update packet when the team is built
+     *
+     * @return this builder, for chaining
+     */
+    public TeamBuilder updateTeamPacket() {
+        this.updateTeam = true;
+        return this;
+    }
+
+    /**
+     * Built a team
+     *
+     * @return the built team
+     */
+    public Team build() {
+        if (!this.teamManager.exists(this.team)) this.teamManager.registerNewTeam(this.team);
+        if (this.updateTeam) {
+            this.team.sendUpdatePacket();
+            this.updateTeam = false;
+        }
+        return this.team;
+    }
+
+}
diff --git a/src/main/java/net/minestom/server/scoreboard/TeamManager.java b/src/main/java/net/minestom/server/scoreboard/TeamManager.java
index 9a27f87d5..eb9687230 100644
--- a/src/main/java/net/minestom/server/scoreboard/TeamManager.java
+++ b/src/main/java/net/minestom/server/scoreboard/TeamManager.java
@@ -1,21 +1,140 @@
 package net.minestom.server.scoreboard;
 
+import net.minestom.server.MinecraftServer;
+import net.minestom.server.chat.ChatColor;
+import net.minestom.server.chat.ColoredText;
+import net.minestom.server.entity.Player;
+import net.minestom.server.network.PacketWriterUtils;
+import net.minestom.server.network.packet.server.ServerPacket;
+
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
-// TODO
+/**
+ * An object which manages all the {@link Team}'s
+ */
 public final class TeamManager {
 
-    // Represents all registered teams
-    private Set<Team> teams = new CopyOnWriteArraySet<>();
+    /**
+     * Represents all registered teams
+     */
+    private final Set<Team> teams;
 
-    public Team createTeam(String teamName) {
-        Team team = new Team(teamName);
-        this.teams.add(team);
-        return team;
+    /**
+     * Default constructor
+     */
+    public TeamManager() {
+        this.teams = new CopyOnWriteArraySet<>();
     }
 
+    /**
+     * Registers a new {@link Team}
+     *
+     * @param team The team to be registered
+     */
+    protected void registerNewTeam(Team team) {
+        this.teams.add(team);
+        this.broadcastPacket(team.getTeamsCreationPacket());
+    }
+
+    /**
+     * Initializes a new {@link TeamBuilder} for creating a team
+     *
+     * @param name The registry name of the team
+     * @return the team builder
+     */
+    public TeamBuilder createBuilder(String name) {
+        return new TeamBuilder(name, this);
+    }
+
+    /**
+     * Creates a {@link Team} with only the registry name
+     *
+     * @param name The registry name
+     * @return the created {@link Team}
+     */
+    public Team createTeam(String name) {
+        return this.createBuilder(name).build();
+    }
+
+    /**
+     * Creates a {@link Team} with the registry name, prefix, suffix and the team color
+     *
+     * @param name      The registry name
+     * @param prefix    The team prefix
+     * @param teamColor The team color
+     * @param suffix    The team suffix
+     * @return the created {@link Team} with a prefix, teamColor and suffix
+     */
+    public Team createTeam(String name, ColoredText prefix, ChatColor teamColor, ColoredText suffix) {
+        return this.createBuilder(name).prefix(prefix).teamColor(teamColor).suffix(suffix).updateTeamPacket().build();
+    }
+
+    /**
+     * Creates a {@link Team} with the registry name, display name, prefix, suffix and the team colro
+     *
+     * @param name        The registry name
+     * @param displayName The display name
+     * @param prefix      The team prefix
+     * @param teamColor   The team color
+     * @param suffix      The team suffix
+     * @return the created {@link Team} with a prefix, teamColor, suffix and the display name
+     */
+    public Team createTeam(String name, ColoredText displayName, ColoredText prefix, ChatColor teamColor, ColoredText suffix) {
+        return this.createBuilder(name).teamDisplayName(displayName).prefix(prefix).teamColor(teamColor).suffix(suffix).updateTeamPacket().build();
+    }
+
+    /**
+     * Gets a {@link Team} with the given name
+     *
+     * @param teamName The registry name of the team
+     * @return a registered {@link Team} or {@code null}
+     */
+    public Team getTeam(String teamName) {
+        for (Team team : this.teams) {
+            if (team.getTeamName().equals(teamName)) return team;
+        }
+        return null;
+    }
+
+    /**
+     * Checks if the given name a registry name of a registered {@link Team}
+     *
+     * @param teamName The name of the team
+     * @return {@code true} if the team is registered, otherwise {@code false}
+     */
+    public boolean exists(String teamName) {
+        for (Team team : this.teams) {
+            if (team.getTeamName().equals(teamName)) return true;
+        }
+        return false;
+    }
+
+    /**
+     * Checks if the given {@link Team} registered
+     *
+     * @param team The searched team
+     * @return {@code true} if the team is registered, otherwise {@code false}
+     */
+    public boolean exists(Team team) {
+        return this.exists(team.getTeamName());
+    }
+
+    /**
+     * Gets a {@link Set} with all registered {@link Team}'s
+     *
+     * @return a {@link Set} with all registered {@link Team}'s
+     */
     public Set<Team> getTeams() {
-        return teams;
+        return this.teams;
+    }
+
+    /**
+     * Broadcasts to all online {@link Player}'s a {@link ServerPacket}
+     *
+     * @param packet The packet to broadcast
+     */
+    private void broadcastPacket(ServerPacket packet) {
+        PacketWriterUtils.writeAndSend(MinecraftServer.getConnectionManager().getOnlinePlayers(), packet);
     }
 }

From 70c969ced7c26ae569f22fad1f55be8ed07ce295 Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Wed, 5 Aug 2020 11:02:54 +0200
Subject: [PATCH 2/6] Deletes teams, gets players/entities of a team

---
 .../server/scoreboard/TeamManager.java        | 76 +++++++++++++++++++
 .../minestom/server/utils/UniqueIdUtils.java  | 23 ++++++
 2 files changed, 99 insertions(+)
 create mode 100644 src/main/java/net/minestom/server/utils/UniqueIdUtils.java

diff --git a/src/main/java/net/minestom/server/scoreboard/TeamManager.java b/src/main/java/net/minestom/server/scoreboard/TeamManager.java
index eb9687230..238b3c8fb 100644
--- a/src/main/java/net/minestom/server/scoreboard/TeamManager.java
+++ b/src/main/java/net/minestom/server/scoreboard/TeamManager.java
@@ -1,12 +1,17 @@
 package net.minestom.server.scoreboard;
 
+import io.netty.buffer.ByteBuf;
 import net.minestom.server.MinecraftServer;
 import net.minestom.server.chat.ChatColor;
 import net.minestom.server.chat.ColoredText;
+import net.minestom.server.entity.LivingEntity;
 import net.minestom.server.entity.Player;
 import net.minestom.server.network.PacketWriterUtils;
 import net.minestom.server.network.packet.server.ServerPacket;
+import net.minestom.server.utils.UniqueIdUtils;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
@@ -37,6 +42,30 @@ public final class TeamManager {
         this.broadcastPacket(team.getTeamsCreationPacket());
     }
 
+    /**
+     * Deletes a {@link Team}
+     *
+     * @param registryName The registry name of team
+     * @return {@code true} if the team was deleted, otherwise {@code false}
+     */
+    public boolean deleteTeam(String registryName) {
+        Team team = this.getTeam(registryName);
+        if (team == null) return false;
+        return this.deleteTeam(team);
+    }
+
+    /**
+     * Deletes a {@link Team}
+     *
+     * @param team The team to be deleted
+     * @return {@code true} if the team was deleted, otherwise {@code false}
+     */
+    public boolean deleteTeam(Team team) {
+        // Sends to all online players a team destroy packet
+        this.broadcastBuffer(team.getTeamsDestroyPacket());
+        return this.teams.remove(team);
+    }
+
     /**
      * Initializes a new {@link TeamBuilder} for creating a team
      *
@@ -120,6 +149,42 @@ public final class TeamManager {
         return this.exists(team.getTeamName());
     }
 
+    /**
+     * Gets a {@link List} with all registered {@link Player} in the team
+     * <br>
+     * <b>Note:</b> The list exclude all entities. To get all entities of the team, you can use {@link #getEntities(Team)}
+     *
+     * @param team The team
+     * @return a {@link List} with all registered {@link Player}
+     */
+    public List<String> getPlayers(Team team) {
+        List<String> players = new ArrayList<>();
+        for (String member : team.getMembers()) {
+            boolean match = UniqueIdUtils.isUniqueId(member);
+
+            if (!match) players.add(member);
+        }
+        return players;
+    }
+
+    /**
+     * Gets a {@link List} with all registered {@link LivingEntity} in the team
+     * <br>
+     * <b>Note:</b> The list exclude all players. To get all players of the team, you can use {@link #getPlayers(Team)}
+     *
+     * @param team The team
+     * @return a {@link List} with all registered {@link LivingEntity}
+     */
+    public List<String> getEntities(Team team) {
+        List<String> entities = new ArrayList<>();
+        for (String member : team.getMembers()) {
+            boolean match = UniqueIdUtils.isUniqueId(member);
+
+            if (match) entities.add(member);
+        }
+        return entities;
+    }
+
     /**
      * Gets a {@link Set} with all registered {@link Team}'s
      *
@@ -137,4 +202,15 @@ public final class TeamManager {
     private void broadcastPacket(ServerPacket packet) {
         PacketWriterUtils.writeAndSend(MinecraftServer.getConnectionManager().getOnlinePlayers(), packet);
     }
+
+    /**
+     * Broadcasts to all online {@link Player}'s a buffer
+     *
+     * @param buffer The buffer to broadcast
+     */
+    private void broadcastBuffer(ByteBuf buffer) {
+        for (Player onlinePlayer : MinecraftServer.getConnectionManager().getOnlinePlayers()) {
+            onlinePlayer.getPlayerConnection().sendPacket(buffer, true);
+        }
+    }
 }
diff --git a/src/main/java/net/minestom/server/utils/UniqueIdUtils.java b/src/main/java/net/minestom/server/utils/UniqueIdUtils.java
new file mode 100644
index 000000000..4774bc436
--- /dev/null
+++ b/src/main/java/net/minestom/server/utils/UniqueIdUtils.java
@@ -0,0 +1,23 @@
+package net.minestom.server.utils;
+
+import java.util.UUID;
+import java.util.regex.Pattern;
+
+/**
+ * An utilities class for {@link UUID}
+ */
+public class UniqueIdUtils {
+
+    public static final Pattern UNIQUE_ID_PATTERN = Pattern.compile("\\b[0-9a-f]{8}\\b-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-\\b[0-9a-f]{12}\\b");
+
+    /**
+     * Checks whether the {@code input} string is an {@link UUID}
+     *
+     * @param input The input string to be checked
+     * @return {@code true} if the input an unique identifier, otherwise {@code false}
+     */
+    public static boolean isUniqueId(String input) {
+        return input.matches(UNIQUE_ID_PATTERN.pattern());
+    }
+
+}

From 1ad20209d0f1dc29406026b9df9a19b9eedddc98 Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Fri, 7 Aug 2020 12:16:56 +0200
Subject: [PATCH 3/6] BelowNameTag synchronisation, documentation

---
 .../net/minestom/server/entity/Player.java    |  17 +-
 .../play/ScoreboardObjectivePacket.java       |  26 ++-
 .../scoreboard/BelowNameScoreboard.java       | 121 +++++++++----
 .../minestom/server/scoreboard/Sidebar.java   | 169 ++++++++++++++++--
 .../minestom/server/utils/UniqueIdUtils.java  |   2 +-
 5 files changed, 274 insertions(+), 61 deletions(-)

diff --git a/src/main/java/net/minestom/server/entity/Player.java b/src/main/java/net/minestom/server/entity/Player.java
index 1137ef94c..dd15f8f76 100644
--- a/src/main/java/net/minestom/server/entity/Player.java
+++ b/src/main/java/net/minestom/server/entity/Player.java
@@ -109,7 +109,7 @@ public class Player extends LivingEntity implements CommandSender {
     private int blockBreakTime;
 
     private Set<BossBar> bossBars = new CopyOnWriteArraySet<>();
-    private BelowNameScoreboard belowNameScoreboard;
+    private BelowNameScoreboard belowNameScoreboard = null;
 
     /**
      * Last damage source to hit this player, used to display the death message.
@@ -1370,26 +1370,25 @@ public class Player extends LivingEntity implements CommandSender {
         return heldSlot;
     }
 
+    /**
+     * Change the tag below the name
+     *
+     * @param belowNameScoreboard The new below name tag
+     */
     public void setBelowNameScoreboard(BelowNameScoreboard belowNameScoreboard) {
-        if (this.belowNameScoreboard == belowNameScoreboard)
-            return;
+        if (this.belowNameScoreboard == belowNameScoreboard) return;
 
         if (this.belowNameScoreboard != null) {
             this.belowNameScoreboard.removeViewer(this);
         }
 
         this.belowNameScoreboard = belowNameScoreboard;
-        if (belowNameScoreboard != null) {
-            belowNameScoreboard.addViewer(this);
-            belowNameScoreboard.displayScoreboard(this);
-            getViewers().forEach(player -> belowNameScoreboard.addViewer(player));
-        }
     }
 
     @Override
     public void setTeam(Team team) {
         super.setTeam(team);
-        if(team != null)
+        if (team != null)
             getPlayerConnection().sendPacket(team.getTeamsCreationPacket());
     }
 
diff --git a/src/main/java/net/minestom/server/network/packet/server/play/ScoreboardObjectivePacket.java b/src/main/java/net/minestom/server/network/packet/server/play/ScoreboardObjectivePacket.java
index 45ad1e17c..46f4969be 100644
--- a/src/main/java/net/minestom/server/network/packet/server/play/ScoreboardObjectivePacket.java
+++ b/src/main/java/net/minestom/server/network/packet/server/play/ScoreboardObjectivePacket.java
@@ -7,10 +7,24 @@ import net.minestom.server.network.packet.server.ServerPacketIdentifier;
 
 public class ScoreboardObjectivePacket implements ServerPacket {
 
+    /**
+     * An unique name for the objective
+     */
     public String objectiveName;
+    /**
+     * 0 = create the scoreboard <br>
+     * 1 = to remove the scoreboard<br>
+     * 2 = to update the display text
+     */
     public byte mode;
+    /**
+     * The text to be displayed for the score
+     */
     public ColoredText objectiveValue;
-    public int type;
+    /**
+     * The type how the score is displayed
+     */
+    public Type type;
 
     @Override
     public void write(PacketWriter writer) {
@@ -19,7 +33,7 @@ public class ScoreboardObjectivePacket implements ServerPacket {
 
         if (mode == 0 || mode == 2) {
             writer.writeSizedString(objectiveValue.toString());
-            writer.writeVarInt(type);
+            writer.writeVarInt(type.ordinal());
         }
     }
 
@@ -27,4 +41,12 @@ public class ScoreboardObjectivePacket implements ServerPacket {
     public int getId() {
         return ServerPacketIdentifier.SCOREBOARD_OBJECTIVE;
     }
+
+    /**
+     * This enumeration represents all available types for the scoreboard objective
+     */
+    public enum Type {
+        INTEGER,
+        HEARTS
+    }
 }
diff --git a/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java b/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java
index 1894ba64b..7d2173afc 100644
--- a/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java
+++ b/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java
@@ -11,68 +11,115 @@ import net.minestom.server.network.player.PlayerConnection;
 import java.util.Collections;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
-import java.util.concurrent.atomic.AtomicInteger;
 
-// TODO fix score and objective refresh
+/**
+ * Represents a scoreboard which rendered a tag below the name
+ */
 public class BelowNameScoreboard implements Viewable {
 
-    private static final AtomicInteger counter = new AtomicInteger();
+    private final Set<Player> viewers = new CopyOnWriteArraySet<>();
+    private final String objectiveName;
 
-    // WARNING: you shouldn't create scoreboards/teams with the same prefixes as those
-    private static final String SCOREBOARD_PREFIX = "bn-";
-    private static final String TEAM_PREFIX = "bnt-";
+    private final ScoreboardObjectivePacket scoreboardObjectivePacket;
+    private final ScoreboardObjectivePacket destructionObjectivePacket;
+    private final DisplayScoreboardPacket displayScoreboardPacket;
 
-    private Set<Player> viewers = new CopyOnWriteArraySet<>();
+    /**
+     * Creates a new below name scoreboard
+     *
+     * @param name  The objective name of the scoreboard
+     * @param value The value of the scoreboard
+     */
+    public BelowNameScoreboard(String name, String value) {
+        this.objectiveName = name;
 
-    private String objectiveName;
+        this.scoreboardObjectivePacket = this.getCreationObjectivePacket(value);
 
-    private ScoreboardObjectivePacket scoreboardObjectivePacket;
-    private DisplayScoreboardPacket displayScoreboardPacket;
+        this.displayScoreboardPacket = new DisplayScoreboardPacket();
+        this.displayScoreboardPacket.position = 2; // Below name
+        this.displayScoreboardPacket.scoreName = this.objectiveName;
 
-    public BelowNameScoreboard() {
-        this.objectiveName = SCOREBOARD_PREFIX + counter.incrementAndGet();
-
-        scoreboardObjectivePacket = new ScoreboardObjectivePacket();
-        scoreboardObjectivePacket.objectiveName = objectiveName;
-        scoreboardObjectivePacket.mode = 0;
-        scoreboardObjectivePacket.objectiveValue = ColoredText.of(objectiveName);
-        scoreboardObjectivePacket.type = 0;
-
-        displayScoreboardPacket = new DisplayScoreboardPacket();
-        displayScoreboardPacket.position = 2; // Below name
-        displayScoreboardPacket.scoreName = objectiveName;
+        this.destructionObjectivePacket = this.getDestructionObjectivePacket();
     }
 
-    public void updateScore(Player player, int score) {
-        UpdateScorePacket updateScorePacket = new UpdateScorePacket();
-        updateScorePacket.entityName = player.getUsername();
-        updateScorePacket.action = 0; // Create/update
-        updateScorePacket.objectiveName = objectiveName;
-        updateScorePacket.value = score;
+    /**
+     * Creates a creation objective packet for the tag below name
+     *
+     * @param value The value of the tag
+     * @return the creation objective packet
+     */
+    private ScoreboardObjectivePacket getCreationObjectivePacket(String value) {
+        ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
+        packet.objectiveName = this.objectiveName;
+        packet.mode = 0; // Create/Update
+        packet.objectiveValue = ColoredText.of(value);
+        packet.type = ScoreboardObjectivePacket.Type.INTEGER;
 
-        sendPacketToViewers(updateScorePacket);
+        return packet;
+    }
+
+    /**
+     * Creates the destruction objective packet for the tag below name
+     *
+     * @return the destruction objective packet
+     */
+    private ScoreboardObjectivePacket getDestructionObjectivePacket() {
+        ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
+        packet.objectiveName = this.objectiveName;
+        packet.mode = 1;
+        packet.objectiveValue = ColoredText.of("");
+        packet.type = ScoreboardObjectivePacket.Type.INTEGER;
+
+        return packet;
+    }
+
+    /**
+     * Updates the score of a {@link Player}
+     *
+     * @param player The player
+     * @param score  The new score
+     */
+    public void updateScore(Player player, int score) {
+        UpdateScorePacket packet = new UpdateScorePacket();
+        packet.entityName = player.getUsername();
+        packet.action = 0; //Create/Update
+        packet.objectiveName = this.objectiveName;
+        packet.value = score;
+
+        // Sends to all viewers an update packet
+        sendPacketToViewers(packet);
     }
 
     @Override
     public boolean addViewer(Player player) {
         boolean result = this.viewers.add(player);
-        PlayerConnection playerConnection = player.getPlayerConnection();
-        playerConnection.sendPacket(scoreboardObjectivePacket);
+        PlayerConnection connection = player.getPlayerConnection();
+
+        if (result) {
+            connection.sendPacket(this.scoreboardObjectivePacket);
+            connection.sendPacket(this.displayScoreboardPacket);
+
+            player.setBelowNameScoreboard(this);
+        }
+
         return result;
     }
 
     @Override
     public boolean removeViewer(Player player) {
-        return this.viewers.remove(player);
+        boolean result = this.viewers.remove(player);
+        PlayerConnection connection = player.getPlayerConnection();
+
+        if (result) {
+            connection.sendPacket(this.destructionObjectivePacket);
+            player.setBelowNameScoreboard(null);
+        }
+
+        return result;
     }
 
     @Override
     public Set<Player> getViewers() {
         return Collections.unmodifiableSet(viewers);
     }
-
-    public void displayScoreboard(Player player) {
-        PlayerConnection playerConnection = player.getPlayerConnection();
-        playerConnection.sendPacket(displayScoreboardPacket);
-    }
 }
diff --git a/src/main/java/net/minestom/server/scoreboard/Sidebar.java b/src/main/java/net/minestom/server/scoreboard/Sidebar.java
index 45a18ffc4..5c4d25afd 100644
--- a/src/main/java/net/minestom/server/scoreboard/Sidebar.java
+++ b/src/main/java/net/minestom/server/scoreboard/Sidebar.java
@@ -18,30 +18,40 @@ import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.CopyOnWriteArraySet;
 import java.util.concurrent.atomic.AtomicInteger;
 
+/**
+ * Represents a sidebar which can contain up to 16 {@link ScoreboardLine}'s
+ */
 public class Sidebar implements Viewable {
 
-    private static final AtomicInteger counter = new AtomicInteger();
+    private static final AtomicInteger COUNTER = new AtomicInteger();
 
     // WARNING: you shouldn't create scoreboards/teams with the same prefixes as those
     private static final String SCOREBOARD_PREFIX = "sb-";
     private static final String TEAM_PREFIX = "sbt-";
 
-    // Limited by notchian client, do not change
+    /**
+     * Limited by the notch client, do not change
+     */
     private static final int MAX_LINES_COUNT = 15;
 
-    private Set<Player> viewers = new CopyOnWriteArraySet<>();
+    private final Set<Player> viewers = new CopyOnWriteArraySet<>();
 
-    private ConcurrentLinkedQueue<ScoreboardLine> lines = new ConcurrentLinkedQueue<>();
-    private IntLinkedOpenHashSet availableColors = new IntLinkedOpenHashSet();
+    private final ConcurrentLinkedQueue<ScoreboardLine> lines = new ConcurrentLinkedQueue<>();
+    private final IntLinkedOpenHashSet availableColors = new IntLinkedOpenHashSet();
 
-    private String objectiveName;
+    private final String objectiveName;
 
     private String title;
 
+    /**
+     * Creates a new sidebar
+     *
+     * @param title The title of the sidebar
+     */
     public Sidebar(String title) {
         this.title = title;
 
-        this.objectiveName = SCOREBOARD_PREFIX + counter.incrementAndGet();
+        this.objectiveName = SCOREBOARD_PREFIX + COUNTER.incrementAndGet();
 
         // Fill available colors for entities name showed in scoreboard
         for (int i = 0; i < 16; i++) {
@@ -49,6 +59,11 @@ public class Sidebar implements Viewable {
         }
     }
 
+    /**
+     * Changes the {@link Sidebar} title
+     *
+     * @param title The new sidebar title
+     */
     public void setTitle(String title) {
         this.title = title;
 
@@ -56,11 +71,16 @@ public class Sidebar implements Viewable {
         scoreboardObjectivePacket.objectiveName = objectiveName;
         scoreboardObjectivePacket.mode = 2; // Update display text
         scoreboardObjectivePacket.objectiveValue = ColoredText.of(title);
-        scoreboardObjectivePacket.type = 0;
+        scoreboardObjectivePacket.type = ScoreboardObjectivePacket.Type.INTEGER;
 
         sendPacketToViewers(scoreboardObjectivePacket);
     }
 
+    /**
+     * Creates a new {@link ScoreboardLine}
+     *
+     * @param scoreboardLine The new scoreboard line
+     */
     public void createLine(ScoreboardLine scoreboardLine) {
         synchronized (lines) {
             Check.stateCondition(lines.size() >= MAX_LINES_COUNT, "You cannot have more than " + MAX_LINES_COUNT + "  lines");
@@ -84,6 +104,12 @@ public class Sidebar implements Viewable {
         }
     }
 
+    /**
+     * Updates a line content through the given identifier
+     *
+     * @param id      The identifier of the line
+     * @param content The new content for the line
+     */
     public void updateLineContent(String id, ColoredText content) {
         final ScoreboardLine scoreboardLine = getLine(id);
         if (scoreboardLine != null) {
@@ -92,6 +118,12 @@ public class Sidebar implements Viewable {
         }
     }
 
+    /**
+     * Updates the score of a line through the given identifier
+     *
+     * @param id    The identifier of the team
+     * @param score The new score for the line
+     */
     public void updateLineScore(String id, int score) {
         final ScoreboardLine scoreboardLine = getLine(id);
         if (scoreboardLine != null) {
@@ -100,6 +132,12 @@ public class Sidebar implements Viewable {
         }
     }
 
+    /**
+     * Gets a {@link ScoreboardLine} through the given identifier
+     *
+     * @param id The identifier of the line
+     * @return a {@link ScoreboardLine} or {@code null}
+     */
     public ScoreboardLine getLine(String id) {
         for (ScoreboardLine line : lines) {
             if (line.id.equals(id))
@@ -108,6 +146,11 @@ public class Sidebar implements Viewable {
         return null;
     }
 
+    /**
+     * Removes a {@link ScoreboardLine} through the given identifier
+     *
+     * @param id The identifier of the line
+     */
     public void removeLine(String id) {
         synchronized (lines) {
             Iterator<ScoreboardLine> iterator = lines.iterator();
@@ -134,7 +177,7 @@ public class Sidebar implements Viewable {
         scoreboardObjectivePacket.objectiveName = objectiveName;
         scoreboardObjectivePacket.mode = 0; // Create scoreboard
         scoreboardObjectivePacket.objectiveValue = ColoredText.of(title);
-        scoreboardObjectivePacket.type = 0; // Type integer
+        scoreboardObjectivePacket.type = ScoreboardObjectivePacket.Type.INTEGER; // Type integer
 
         DisplayScoreboardPacket displayScoreboardPacket = new DisplayScoreboardPacket();
         displayScoreboardPacket.position = 1; // Sidebar
@@ -171,15 +214,33 @@ public class Sidebar implements Viewable {
         return viewers;
     }
 
+    /**
+     * This class is used to create a line for the sidebar.
+     */
     public static class ScoreboardLine {
 
-        private String id; // ID used to modify the line later
+        /**
+         * The identifier is used to modify the line later
+         */
+        private String id;
+        /**
+         * The content for the line
+         */
         private ColoredText content;
+        /**
+         * The score of the line
+         */
         private int line;
 
         private String teamName;
-        private int colorName; // Name of the score (entityName) which is essentially an ID
+        /**
+         * The name of the score ({@code entityName}) which is essentially an identifier
+         */
+        private int colorName;
         private String entityName;
+        /**
+         * The sidebar team of the line
+         */
         private SidebarTeam sidebarTeam;
 
         public ScoreboardLine(String id, ColoredText content, int line) {
@@ -187,17 +248,32 @@ public class Sidebar implements Viewable {
             this.content = content;
             this.line = line;
 
-            this.teamName = TEAM_PREFIX + counter.incrementAndGet();
+            this.teamName = TEAM_PREFIX + COUNTER.incrementAndGet();
         }
 
+        /**
+         * Gets the identifier of the line
+         *
+         * @return the line identifier
+         */
         public String getId() {
             return id;
         }
 
+        /**
+         * Gets the content of the line
+         *
+         * @return The line content
+         */
         public ColoredText getContent() {
             return sidebarTeam == null ? content : sidebarTeam.getPrefix();
         }
 
+        /**
+         * Gets the position of the line
+         *
+         * @return the line position
+         */
         public int getLine() {
             return line;
         }
@@ -208,6 +284,9 @@ public class Sidebar implements Viewable {
             }
         }
 
+        /**
+         * Creates a new {@link SidebarTeam}
+         */
         private void createTeam() {
             this.entityName = ChatParser.COLOR_CHAR + Integer.toHexString(colorName);
 
@@ -220,6 +299,12 @@ public class Sidebar implements Viewable {
             }
         }
 
+        /**
+         * Gets a score creation packet
+         *
+         * @param objectiveName The objective name to be updated
+         * @return a {@link UpdateScorePacket}
+         */
         private UpdateScorePacket getScoreCreationPacket(String objectiveName) {
             UpdateScorePacket updateScorePacket = new UpdateScorePacket();
             updateScorePacket.entityName = entityName;
@@ -229,6 +314,12 @@ public class Sidebar implements Viewable {
             return updateScorePacket;
         }
 
+        /**
+         * Gets a score destruction packet
+         *
+         * @param objectiveName The objective name to be destroyed
+         * @return a {@link UpdateScorePacket}
+         */
         private UpdateScorePacket getScoreDestructionPacket(String objectiveName) {
             UpdateScorePacket updateScorePacket = new UpdateScorePacket();
             updateScorePacket.entityName = entityName;
@@ -237,18 +328,33 @@ public class Sidebar implements Viewable {
             return updateScorePacket;
         }
 
+        /**
+         * Gets a line score update packet
+         *
+         * @param objectiveName The objective name to be updated
+         * @param score         The new score
+         * @return a {@link UpdateScorePacket}
+         */
         private UpdateScorePacket getLineScoreUpdatePacket(String objectiveName, int score) {
             UpdateScorePacket updateScorePacket = getScoreCreationPacket(objectiveName);
             updateScorePacket.value = score;
             return updateScorePacket;
         }
 
+        /**
+         * Refresh the prefix of the {@link SidebarTeam}
+         *
+         * @param content The new content
+         */
         private void refreshContent(ColoredText content) {
             this.sidebarTeam.refreshPrefix(content);
         }
 
     }
 
+    /**
+     * This class is used to create a team for the sidebar
+     */
     private static class SidebarTeam {
 
         private String teamName;
@@ -262,6 +368,14 @@ public class Sidebar implements Viewable {
         private int teamColor = 2;
 
 
+        /**
+         * The constructor to creates a team
+         *
+         * @param teamName   The registry name of the team
+         * @param prefix     The team prefix
+         * @param suffix     The team suffix
+         * @param entityName The team entity name
+         */
         private SidebarTeam(String teamName, ColoredText prefix, ColoredText suffix, String entityName) {
             this.teamName = teamName;
             this.prefix = prefix;
@@ -269,6 +383,11 @@ public class Sidebar implements Viewable {
             this.entityName = entityName;
         }
 
+        /**
+         * Gets a team creation packet
+         *
+         * @return a {@link TeamsPacket} which creates a new team
+         */
         private TeamsPacket getCreationPacket() {
             TeamsPacket teamsPacket = new TeamsPacket();
             teamsPacket.teamName = teamName;
@@ -284,6 +403,11 @@ public class Sidebar implements Viewable {
             return teamsPacket;
         }
 
+        /**
+         * Gets a team destruction packet
+         *
+         * @return a {@link TeamsPacket} which destroyed a team
+         */
         private TeamsPacket getDestructionPacket() {
             TeamsPacket teamsPacket = new TeamsPacket();
             teamsPacket.teamName = teamName;
@@ -291,6 +415,12 @@ public class Sidebar implements Viewable {
             return teamsPacket;
         }
 
+        /**
+         * Updates the prefix of the {@link SidebarTeam}
+         *
+         * @param prefix The new prefix
+         * @return a {@link TeamsPacket} with the updated prefix
+         */
         private TeamsPacket updatePrefix(ColoredText prefix) {
             TeamsPacket teamsPacket = new TeamsPacket();
             teamsPacket.teamName = teamName;
@@ -305,14 +435,29 @@ public class Sidebar implements Viewable {
             return teamsPacket;
         }
 
+        /**
+         * Gets the entity name of the team
+         *
+         * @return the entity name
+         */
         private String getEntityName() {
             return entityName;
         }
 
+        /**
+         * Gets the prefix of the team
+         *
+         * @return the prefix
+         */
         private ColoredText getPrefix() {
             return prefix;
         }
 
+        /**
+         * Refresh the prefix of the {@link SidebarTeam}
+         *
+         * @param prefix The refreshed prefix
+         */
         private void refreshPrefix(ColoredText prefix) {
             this.prefix = prefix;
         }
diff --git a/src/main/java/net/minestom/server/utils/UniqueIdUtils.java b/src/main/java/net/minestom/server/utils/UniqueIdUtils.java
index 4774bc436..a0999d351 100644
--- a/src/main/java/net/minestom/server/utils/UniqueIdUtils.java
+++ b/src/main/java/net/minestom/server/utils/UniqueIdUtils.java
@@ -6,7 +6,7 @@ import java.util.regex.Pattern;
 /**
  * An utilities class for {@link UUID}
  */
-public class UniqueIdUtils {
+public final class UniqueIdUtils {
 
     public static final Pattern UNIQUE_ID_PATTERN = Pattern.compile("\\b[0-9a-f]{8}\\b-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-\\b[0-9a-f]{12}\\b");
 

From bbe9cda40b67c9732d20999edd6d6507dc6a85c4 Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Sat, 8 Aug 2020 13:36:15 +0200
Subject: [PATCH 4/6] Renamed BelowNameScoreboard to BelowNameTag

---
 .../java/net/minestom/server/entity/Player.java  | 16 ++++++++--------
 ...elowNameScoreboard.java => BelowNameTag.java} |  8 ++++----
 2 files changed, 12 insertions(+), 12 deletions(-)
 rename src/main/java/net/minestom/server/scoreboard/{BelowNameScoreboard.java => BelowNameTag.java} (94%)

diff --git a/src/main/java/net/minestom/server/entity/Player.java b/src/main/java/net/minestom/server/entity/Player.java
index dd15f8f76..83497888b 100644
--- a/src/main/java/net/minestom/server/entity/Player.java
+++ b/src/main/java/net/minestom/server/entity/Player.java
@@ -34,7 +34,7 @@ import net.minestom.server.network.player.PlayerConnection;
 import net.minestom.server.recipe.Recipe;
 import net.minestom.server.recipe.RecipeManager;
 import net.minestom.server.resourcepack.ResourcePack;
-import net.minestom.server.scoreboard.BelowNameScoreboard;
+import net.minestom.server.scoreboard.BelowNameTag;
 import net.minestom.server.scoreboard.Team;
 import net.minestom.server.sound.Sound;
 import net.minestom.server.sound.SoundCategory;
@@ -109,7 +109,7 @@ public class Player extends LivingEntity implements CommandSender {
     private int blockBreakTime;
 
     private Set<BossBar> bossBars = new CopyOnWriteArraySet<>();
-    private BelowNameScoreboard belowNameScoreboard = null;
+    private BelowNameTag belowNameTag = null;
 
     /**
      * Last damage source to hit this player, used to display the death message.
@@ -1373,16 +1373,16 @@ public class Player extends LivingEntity implements CommandSender {
     /**
      * Change the tag below the name
      *
-     * @param belowNameScoreboard The new below name tag
+     * @param belowNameTag The new below name tag
      */
-    public void setBelowNameScoreboard(BelowNameScoreboard belowNameScoreboard) {
-        if (this.belowNameScoreboard == belowNameScoreboard) return;
+    public void setBelowNameTag(BelowNameTag belowNameTag) {
+        if (this.belowNameTag == belowNameTag) return;
 
-        if (this.belowNameScoreboard != null) {
-            this.belowNameScoreboard.removeViewer(this);
+        if (this.belowNameTag != null) {
+            this.belowNameTag.removeViewer(this);
         }
 
-        this.belowNameScoreboard = belowNameScoreboard;
+        this.belowNameTag = belowNameTag;
     }
 
     @Override
diff --git a/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java b/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
similarity index 94%
rename from src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java
rename to src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
index 7d2173afc..672aca71d 100644
--- a/src/main/java/net/minestom/server/scoreboard/BelowNameScoreboard.java
+++ b/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
@@ -15,7 +15,7 @@ import java.util.concurrent.CopyOnWriteArraySet;
 /**
  * Represents a scoreboard which rendered a tag below the name
  */
-public class BelowNameScoreboard implements Viewable {
+public class BelowNameTag implements Viewable {
 
     private final Set<Player> viewers = new CopyOnWriteArraySet<>();
     private final String objectiveName;
@@ -30,7 +30,7 @@ public class BelowNameScoreboard implements Viewable {
      * @param name  The objective name of the scoreboard
      * @param value The value of the scoreboard
      */
-    public BelowNameScoreboard(String name, String value) {
+    public BelowNameTag(String name, String value) {
         this.objectiveName = name;
 
         this.scoreboardObjectivePacket = this.getCreationObjectivePacket(value);
@@ -99,7 +99,7 @@ public class BelowNameScoreboard implements Viewable {
             connection.sendPacket(this.scoreboardObjectivePacket);
             connection.sendPacket(this.displayScoreboardPacket);
 
-            player.setBelowNameScoreboard(this);
+            player.setBelowNameTag(this);
         }
 
         return result;
@@ -112,7 +112,7 @@ public class BelowNameScoreboard implements Viewable {
 
         if (result) {
             connection.sendPacket(this.destructionObjectivePacket);
-            player.setBelowNameScoreboard(null);
+            player.setBelowNameTag(null);
         }
 
         return result;

From 141eed466caf92bb8387d077773c84f59655029d Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Sat, 8 Aug 2020 23:22:58 +0200
Subject: [PATCH 5/6] Added Scoreboard interface and TabList Scoreboard

---
 .../server/scoreboard/BelowNameTag.java       | 76 +++--------------
 .../server/scoreboard/Scoreboard.java         | 82 ++++++++++++++++++
 .../minestom/server/scoreboard/Sidebar.java   | 27 +++---
 .../minestom/server/scoreboard/TabList.java   | 85 +++++++++++++++++++
 4 files changed, 192 insertions(+), 78 deletions(-)
 create mode 100644 src/main/java/net/minestom/server/scoreboard/Scoreboard.java
 create mode 100644 src/main/java/net/minestom/server/scoreboard/TabList.java

diff --git a/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java b/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
index 672aca71d..03210fc64 100644
--- a/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
+++ b/src/main/java/net/minestom/server/scoreboard/BelowNameTag.java
@@ -1,11 +1,7 @@
 package net.minestom.server.scoreboard;
 
-import net.minestom.server.Viewable;
-import net.minestom.server.chat.ColoredText;
 import net.minestom.server.entity.Player;
-import net.minestom.server.network.packet.server.play.DisplayScoreboardPacket;
 import net.minestom.server.network.packet.server.play.ScoreboardObjectivePacket;
-import net.minestom.server.network.packet.server.play.UpdateScorePacket;
 import net.minestom.server.network.player.PlayerConnection;
 
 import java.util.Collections;
@@ -15,14 +11,17 @@ import java.util.concurrent.CopyOnWriteArraySet;
 /**
  * Represents a scoreboard which rendered a tag below the name
  */
-public class BelowNameTag implements Viewable {
+public class BelowNameTag implements Scoreboard {
+
+    /**
+     * <b>WARNING:</b> You shouldn't create scoreboards with the same prefix as those
+     */
+    public static final String BELOW_NAME_TAG_PREFIX = "bnt-";
 
     private final Set<Player> viewers = new CopyOnWriteArraySet<>();
     private final String objectiveName;
 
     private final ScoreboardObjectivePacket scoreboardObjectivePacket;
-    private final ScoreboardObjectivePacket destructionObjectivePacket;
-    private final DisplayScoreboardPacket displayScoreboardPacket;
 
     /**
      * Creates a new below name scoreboard
@@ -31,63 +30,14 @@ public class BelowNameTag implements Viewable {
      * @param value The value of the scoreboard
      */
     public BelowNameTag(String name, String value) {
-        this.objectiveName = name;
+        this.objectiveName = BELOW_NAME_TAG_PREFIX + name;
 
-        this.scoreboardObjectivePacket = this.getCreationObjectivePacket(value);
-
-        this.displayScoreboardPacket = new DisplayScoreboardPacket();
-        this.displayScoreboardPacket.position = 2; // Below name
-        this.displayScoreboardPacket.scoreName = this.objectiveName;
-
-        this.destructionObjectivePacket = this.getDestructionObjectivePacket();
+        this.scoreboardObjectivePacket = this.getCreationObjectivePacket(value, ScoreboardObjectivePacket.Type.INTEGER);
     }
 
-    /**
-     * Creates a creation objective packet for the tag below name
-     *
-     * @param value The value of the tag
-     * @return the creation objective packet
-     */
-    private ScoreboardObjectivePacket getCreationObjectivePacket(String value) {
-        ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
-        packet.objectiveName = this.objectiveName;
-        packet.mode = 0; // Create/Update
-        packet.objectiveValue = ColoredText.of(value);
-        packet.type = ScoreboardObjectivePacket.Type.INTEGER;
-
-        return packet;
-    }
-
-    /**
-     * Creates the destruction objective packet for the tag below name
-     *
-     * @return the destruction objective packet
-     */
-    private ScoreboardObjectivePacket getDestructionObjectivePacket() {
-        ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
-        packet.objectiveName = this.objectiveName;
-        packet.mode = 1;
-        packet.objectiveValue = ColoredText.of("");
-        packet.type = ScoreboardObjectivePacket.Type.INTEGER;
-
-        return packet;
-    }
-
-    /**
-     * Updates the score of a {@link Player}
-     *
-     * @param player The player
-     * @param score  The new score
-     */
-    public void updateScore(Player player, int score) {
-        UpdateScorePacket packet = new UpdateScorePacket();
-        packet.entityName = player.getUsername();
-        packet.action = 0; //Create/Update
-        packet.objectiveName = this.objectiveName;
-        packet.value = score;
-
-        // Sends to all viewers an update packet
-        sendPacketToViewers(packet);
+    @Override
+    public String getObjectiveName() {
+        return this.objectiveName;
     }
 
     @Override
@@ -97,7 +47,7 @@ public class BelowNameTag implements Viewable {
 
         if (result) {
             connection.sendPacket(this.scoreboardObjectivePacket);
-            connection.sendPacket(this.displayScoreboardPacket);
+            connection.sendPacket(this.getDisplayScoreboardPacket((byte) 2));
 
             player.setBelowNameTag(this);
         }
@@ -111,7 +61,7 @@ public class BelowNameTag implements Viewable {
         PlayerConnection connection = player.getPlayerConnection();
 
         if (result) {
-            connection.sendPacket(this.destructionObjectivePacket);
+            connection.sendPacket(this.getDestructionObjectivePacket());
             player.setBelowNameTag(null);
         }
 
diff --git a/src/main/java/net/minestom/server/scoreboard/Scoreboard.java b/src/main/java/net/minestom/server/scoreboard/Scoreboard.java
new file mode 100644
index 000000000..2361ae226
--- /dev/null
+++ b/src/main/java/net/minestom/server/scoreboard/Scoreboard.java
@@ -0,0 +1,82 @@
+package net.minestom.server.scoreboard;
+
+import net.minestom.server.Viewable;
+import net.minestom.server.chat.ColoredText;
+import net.minestom.server.entity.Player;
+import net.minestom.server.network.packet.server.play.DisplayScoreboardPacket;
+import net.minestom.server.network.packet.server.play.ScoreboardObjectivePacket;
+import net.minestom.server.network.packet.server.play.UpdateScorePacket;
+
+/**
+ * This interface represents all scoreboard of Minecraft
+ */
+public interface Scoreboard extends Viewable {
+
+    /**
+     * Creates a creation objective packet
+     *
+     * @param value The value for the objective
+     * @param type  The type for the objective
+     * @return the creation objective packet
+     */
+    default ScoreboardObjectivePacket getCreationObjectivePacket(String value, ScoreboardObjectivePacket.Type type) {
+        final ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
+        packet.objectiveName = this.getObjectiveName();
+        packet.mode = 0; // Create Scoreboard
+        packet.objectiveValue = ColoredText.of(value);
+        packet.type = type;
+
+        return packet;
+    }
+
+    /**
+     * Creates the destruction objective packet
+     *
+     * @return the destruction objective packet
+     */
+    default ScoreboardObjectivePacket getDestructionObjectivePacket() {
+        final ScoreboardObjectivePacket packet = new ScoreboardObjectivePacket();
+        packet.objectiveName = this.getObjectiveName();
+        packet.mode = 1; // Destroy Scoreboard
+
+        return packet;
+    }
+
+    /**
+     * Creates the {@link DisplayScoreboardPacket}
+     *
+     * @param position The position of the scoreboard
+     * @return the created display scoreboard packet
+     */
+    default DisplayScoreboardPacket getDisplayScoreboardPacket(byte position) {
+        final DisplayScoreboardPacket packet = new DisplayScoreboardPacket();
+        packet.position = position;
+        packet.scoreName = this.getObjectiveName();
+
+        return packet;
+    }
+
+    /**
+     * Updates the score of a {@link Player}
+     *
+     * @param player The player
+     * @param score  The new score
+     */
+    default void updateScore(Player player, int score) {
+        final UpdateScorePacket packet = new UpdateScorePacket();
+        packet.entityName = player.getUsername();
+        packet.action = 0; // Create/Update score
+        packet.objectiveName = this.getObjectiveName();
+        packet.value = score;
+
+        sendPacketsToViewers(packet);
+    }
+
+    /**
+     * Gets the objective name of the scoreboard
+     *
+     * @return the objective name
+     */
+    String getObjectiveName();
+
+}
diff --git a/src/main/java/net/minestom/server/scoreboard/Sidebar.java b/src/main/java/net/minestom/server/scoreboard/Sidebar.java
index 5c4d25afd..27fdc53f6 100644
--- a/src/main/java/net/minestom/server/scoreboard/Sidebar.java
+++ b/src/main/java/net/minestom/server/scoreboard/Sidebar.java
@@ -1,7 +1,6 @@
 package net.minestom.server.scoreboard;
 
 import it.unimi.dsi.fastutil.ints.IntLinkedOpenHashSet;
-import net.minestom.server.Viewable;
 import net.minestom.server.chat.ChatParser;
 import net.minestom.server.chat.ColoredText;
 import net.minestom.server.entity.Player;
@@ -21,11 +20,13 @@ import java.util.concurrent.atomic.AtomicInteger;
 /**
  * Represents a sidebar which can contain up to 16 {@link ScoreboardLine}'s
  */
-public class Sidebar implements Viewable {
+public class Sidebar implements Scoreboard {
 
     private static final AtomicInteger COUNTER = new AtomicInteger();
 
-    // WARNING: you shouldn't create scoreboards/teams with the same prefixes as those
+    /**
+     * <b>WARNING:</b> You shouldn't create scoreboards/teams with the same prefixes as those
+     */
     private static final String SCOREBOARD_PREFIX = "sb-";
     private static final String TEAM_PREFIX = "sbt-";
 
@@ -173,15 +174,8 @@ public class Sidebar implements Viewable {
         final boolean result = this.viewers.add(player);
         PlayerConnection playerConnection = player.getPlayerConnection();
 
-        ScoreboardObjectivePacket scoreboardObjectivePacket = new ScoreboardObjectivePacket();
-        scoreboardObjectivePacket.objectiveName = objectiveName;
-        scoreboardObjectivePacket.mode = 0; // Create scoreboard
-        scoreboardObjectivePacket.objectiveValue = ColoredText.of(title);
-        scoreboardObjectivePacket.type = ScoreboardObjectivePacket.Type.INTEGER; // Type integer
-
-        DisplayScoreboardPacket displayScoreboardPacket = new DisplayScoreboardPacket();
-        displayScoreboardPacket.position = 1; // Sidebar
-        displayScoreboardPacket.scoreName = objectiveName;
+        ScoreboardObjectivePacket scoreboardObjectivePacket = this.getCreationObjectivePacket(this.title, ScoreboardObjectivePacket.Type.INTEGER);
+        DisplayScoreboardPacket displayScoreboardPacket = this.getDisplayScoreboardPacket((byte) 1);
 
         playerConnection.sendPacket(scoreboardObjectivePacket); // Creative objective
         playerConnection.sendPacket(displayScoreboardPacket); // Show sidebar scoreboard (wait for scores packet)
@@ -197,9 +191,7 @@ public class Sidebar implements Viewable {
     public boolean removeViewer(Player player) {
         boolean result = this.viewers.remove(player);
         PlayerConnection playerConnection = player.getPlayerConnection();
-        ScoreboardObjectivePacket scoreboardObjectivePacket = new ScoreboardObjectivePacket();
-        scoreboardObjectivePacket.objectiveName = objectiveName;
-        scoreboardObjectivePacket.mode = 1; // Remove
+        ScoreboardObjectivePacket scoreboardObjectivePacket = this.getDestructionObjectivePacket();
         playerConnection.sendPacket(scoreboardObjectivePacket);
 
         for (ScoreboardLine line : lines) {
@@ -214,6 +206,11 @@ public class Sidebar implements Viewable {
         return viewers;
     }
 
+    @Override
+    public String getObjectiveName() {
+        return this.objectiveName;
+    }
+
     /**
      * This class is used to create a line for the sidebar.
      */
diff --git a/src/main/java/net/minestom/server/scoreboard/TabList.java b/src/main/java/net/minestom/server/scoreboard/TabList.java
new file mode 100644
index 000000000..7e9192b13
--- /dev/null
+++ b/src/main/java/net/minestom/server/scoreboard/TabList.java
@@ -0,0 +1,85 @@
+package net.minestom.server.scoreboard;
+
+import net.minestom.server.entity.Player;
+import net.minestom.server.network.packet.server.play.ScoreboardObjectivePacket;
+import net.minestom.server.network.player.PlayerConnection;
+
+import java.util.Collections;
+import java.util.Set;
+import java.util.concurrent.CopyOnWriteArraySet;
+
+/**
+ * Represents the {@link Player} tab list as a {@link Scoreboard}
+ */
+public class TabList implements Scoreboard {
+
+    /**
+     * <b>WARNING:</b> You shouldn't create scoreboards with the same prefix as those
+     */
+    private static final String TAB_LIST_PREFIX = "tl-";
+
+    private final Set<Player> viewers;
+    private final String objectiveName;
+
+    private ScoreboardObjectivePacket.Type type;
+
+    public TabList(String name, ScoreboardObjectivePacket.Type type) {
+        this.viewers = new CopyOnWriteArraySet<>();
+        this.objectiveName = TAB_LIST_PREFIX + name;
+
+        this.type = type;
+    }
+
+    /**
+     * Gets the scoreboard objective type
+     *
+     * @return the scoreboard objective type
+     */
+    public ScoreboardObjectivePacket.Type getType() {
+        return type;
+    }
+
+    /**
+     * Changes the scoreboard objective type
+     *
+     * @param type The new type for the objective
+     */
+    public void setType(ScoreboardObjectivePacket.Type type) {
+        this.type = type;
+    }
+
+    @Override
+    public boolean addViewer(Player player) {
+        boolean result = this.viewers.add(player);
+        PlayerConnection connection = player.getPlayerConnection();
+
+        if (result) {
+            connection.sendPacket(this.getCreationObjectivePacket("", this.type));
+            connection.sendPacket(this.getDisplayScoreboardPacket((byte) 0));
+        }
+
+        return result;
+    }
+
+    @Override
+    public boolean removeViewer(Player player) {
+        boolean result = this.viewers.remove(player);
+        PlayerConnection connection = player.getPlayerConnection();
+
+        if (result) {
+            connection.sendPacket(this.getDestructionObjectivePacket());
+        }
+
+        return result;
+    }
+
+    @Override
+    public Set<Player> getViewers() {
+        return Collections.unmodifiableSet(this.viewers);
+    }
+
+    @Override
+    public String getObjectiveName() {
+        return this.objectiveName;
+    }
+}

From ba07fa78f0a2b6f0a4787499d206a68c02657940 Mon Sep 17 00:00:00 2001
From: R0bbyYT <r0bby@gmx.net>
Date: Sun, 9 Aug 2020 17:10:58 +0200
Subject: [PATCH 6/6] Fixed

---
 .../net/minestom/server/entity/Player.java    | 49 +++++++------------
 1 file changed, 19 insertions(+), 30 deletions(-)

diff --git a/src/main/java/net/minestom/server/entity/Player.java b/src/main/java/net/minestom/server/entity/Player.java
index 7f8cb8edd..85b759036 100644
--- a/src/main/java/net/minestom/server/entity/Player.java
+++ b/src/main/java/net/minestom/server/entity/Player.java
@@ -33,7 +33,7 @@ import net.minestom.server.network.player.PlayerConnection;
 import net.minestom.server.recipe.Recipe;
 import net.minestom.server.recipe.RecipeManager;
 import net.minestom.server.resourcepack.ResourcePack;
-import net.minestom.server.scoreboard.BelowNameScoreboard;
+import net.minestom.server.scoreboard.BelowNameTag;
 import net.minestom.server.scoreboard.Team;
 import net.minestom.server.sound.Sound;
 import net.minestom.server.sound.SoundCategory;
@@ -107,8 +107,7 @@ public class Player extends LivingEntity implements CommandSender {
     private byte targetLastStage;
     private int blockBreakTime;
 
-    private Team team;
-    private BelowNameScoreboard belowNameScoreboard;
+    private BelowNameTag belowNameTag;
 
     /**
      * Last damage source to hit this player, used to display the death message.
@@ -524,8 +523,8 @@ public class Player extends LivingEntity implements CommandSender {
         viewerConnection.sendPacket(getRemovePlayerToList());
 
         // Team
-        if (team != null && team.getPlayers().size() == 1) // If team only contains "this" player
-            viewerConnection.sendPacket(team.createTeamDestructionPacket());
+        if (this.getTeam() != null && this.getTeam().getMembers().size() == 1) // If team only contains "this" player
+            viewerConnection.sendPacket(this.getTeam().createTeamDestructionPacket());
         return result;
     }
 
@@ -1370,34 +1369,24 @@ public class Player extends LivingEntity implements CommandSender {
     }
 
     public void setTeam(Team team) {
-        if (this.team == team)
-            return;
-
-        if (this.team != null) {
-            this.team.removePlayer(this);
-        }
-
-        this.team = team;
-        if (team != null) {
-            team.addPlayer(this);
-            sendPacketToViewers(team.getTeamsCreationPacket()); // FIXME: only if viewer hasn't already register this team
-        }
+        super.setTeam(team);
+        if(team != null)
+            getPlayerConnection().sendPacket(team.getTeamsCreationPacket());
     }
 
-    public void setBelowNameScoreboard(BelowNameScoreboard belowNameScoreboard) {
-        if (this.belowNameScoreboard == belowNameScoreboard)
-            return;
+    /**
+     * Change the tag below the name
+     *
+     * @param belowNameTag The new below name tag
+     */
+    public void setBelowNameTag(BelowNameTag belowNameTag) {
+        if (this.belowNameTag == belowNameTag) return;
 
-        if (this.belowNameScoreboard != null) {
-            this.belowNameScoreboard.removeViewer(this);
+        if (this.belowNameTag != null) {
+            this.belowNameTag.removeViewer(this);
         }
 
-        this.belowNameScoreboard = belowNameScoreboard;
-        if (belowNameScoreboard != null) {
-            belowNameScoreboard.addViewer(this);
-            belowNameScoreboard.displayScoreboard(this);
-            getViewers().forEach(player -> belowNameScoreboard.addViewer(player));
-        }
+        this.belowNameTag = belowNameTag;
     }
 
     /**
@@ -1969,8 +1958,8 @@ public class Player extends LivingEntity implements CommandSender {
         }
 
         // Team
-        if (team != null)
-            connection.sendPacket(team.getTeamsCreationPacket());
+        if (this.getTeam() != null)
+            connection.sendPacket(this.getTeam().getTeamsCreationPacket());
 
         EntityHeadLookPacket entityHeadLookPacket = new EntityHeadLookPacket();
         entityHeadLookPacket.entityId = getEntityId();