Add BossBar API (#213)

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

@@ -17,6 +17,9 @@ import com.velocitypowered.api.proxy.server.ServerInfo;
 import com.velocitypowered.api.util.Favicon;
 import com.velocitypowered.api.util.GameProfile;
 import com.velocitypowered.api.util.ProxyVersion;
+import com.velocitypowered.api.util.bossbar.BossBar;
+import com.velocitypowered.api.util.bossbar.BossBarColor;
+import com.velocitypowered.api.util.bossbar.BossBarOverlay;
 import com.velocitypowered.proxy.command.GlistCommand;
 import com.velocitypowered.proxy.command.ServerCommand;
 import com.velocitypowered.proxy.command.ShutdownCommand;
@@ -38,6 +41,7 @@ import com.velocitypowered.proxy.server.ServerMap;
 import com.velocitypowered.proxy.util.AddressUtil;
 import com.velocitypowered.proxy.util.EncryptionUtils;
 import com.velocitypowered.proxy.util.VelocityChannelRegistrar;
+import com.velocitypowered.proxy.util.bossbar.VelocityBossBar;
 import com.velocitypowered.proxy.util.ratelimit.Ratelimiter;
 import com.velocitypowered.proxy.util.ratelimit.Ratelimiters;
 import io.netty.bootstrap.Bootstrap;
@@ -66,6 +70,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.checkerframework.checker.nullness.qual.EnsuresNonNull;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.RequiresNonNull;
 
 public class VelocityServer implements ProxyServer {
@@ -133,6 +138,15 @@ public class VelocityServer implements ProxyServer {
     return new ProxyVersion(implName, implVendor, implVersion);
   }
 
+  @Override
+  public @NonNull BossBar createBossBar(
+      @NonNull Component title,
+      @NonNull BossBarColor color,
+      @NonNull BossBarOverlay overlay,
+      float progress) {
+    return new VelocityBossBar(title, color, overlay, progress);
+  }
+
   @Override
   public VelocityCommandManager getCommandManager() {
     return commandManager;

proxy/src/main/java/com/velocitypowered/proxy/util/bossbar/VelocityBossBar.java

@@ -0,0 +1,276 @@
+package com.velocitypowered.proxy.util.bossbar;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import com.google.common.collect.ImmutableList;
+import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.api.proxy.Player;
+import com.velocitypowered.api.util.bossbar.BossBarColor;
+import com.velocitypowered.api.util.bossbar.BossBarFlag;
+import com.velocitypowered.api.util.bossbar.BossBarOverlay;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
+import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.packet.BossBar;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+import net.kyori.text.Component;
+import net.kyori.text.serializer.gson.GsonComponentSerializer;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+public class VelocityBossBar implements com.velocitypowered.api.util.bossbar.BossBar {
+
+  private final List<Player> players;
+  private final Set<BossBarFlag> flags;
+  private final UUID uuid;
+  private boolean visible;
+  private Component title;
+  private float progress;
+  private BossBarColor color;
+  private BossBarOverlay overlay;
+
+  /**
+   * Creates a new boss bar.
+   * @param title the title for the bar
+   * @param color the color of the bar
+   * @param overlay the overlay to use
+   * @param progress the progress of the bar
+   */
+  public VelocityBossBar(
+      Component title, BossBarColor color, BossBarOverlay overlay, float progress) {
+    this.title = checkNotNull(title, "title");
+    this.color = checkNotNull(color, "color");
+    this.overlay = checkNotNull(overlay, "overlay");
+    this.progress = progress;
+    if (progress > 1 || progress < 0) {
+      throw new IllegalArgumentException("Progress not between 0 and 1");
+    }
+    this.uuid = UUID.randomUUID();
+    visible = true;
+    players = new ArrayList<>();
+    flags = EnumSet.noneOf(BossBarFlag.class);
+  }
+
+  @Override
+  public void addPlayers(@NonNull Iterable<Player> players) {
+    checkNotNull(players, "players");
+    for (Player player : players) {
+      addPlayer(player);
+    }
+  }
+
+  @Override
+  public void addPlayer(@NonNull Player player) {
+    checkNotNull(player, "player");
+    if (!players.contains(player)) {
+      players.add(player);
+    }
+    if (player.isActive() && visible) {
+      sendPacket(player, addPacket());
+    }
+  }
+
+  @Override
+  public void removePlayer(@NonNull Player player) {
+    checkNotNull(player, "player");
+    players.remove(player);
+    if (player.isActive()) {
+      sendPacket(player, removePacket());
+    }
+  }
+
+  @Override
+  public void removePlayers(@NonNull Iterable<Player> players) {
+    checkNotNull(players, "players");
+    for (Player player : players) {
+      removePlayer(player);
+    }
+  }
+
+  @Override
+  public void removeAllPlayers() {
+    removePlayers(ImmutableList.copyOf(players));
+  }
+
+  @Override
+  public @NonNull Component getTitle() {
+    return title;
+  }
+
+  @Override
+  public void setTitle(@NonNull Component title) {
+    this.title = checkNotNull(title, "title");
+    if (visible) {
+      BossBar bar = new BossBar();
+      bar.setUuid(uuid);
+      bar.setAction(BossBar.UPDATE_NAME);
+      bar.setName(GsonComponentSerializer.INSTANCE.serialize(title));
+      sendToAffected(bar);
+    }
+  }
+
+  @Override
+  public float getProgress() {
+    return progress;
+  }
+
+  @Override
+  public void setProgress(float progress) {
+    if (progress > 1 || progress < 0) {
+      throw new IllegalArgumentException("Progress should be between 0 and 1");
+    }
+    this.progress = progress;
+    if (visible) {
+      BossBar bar = new BossBar();
+      bar.setUuid(uuid);
+      bar.setAction(BossBar.UPDATE_PERCENT);
+      bar.setPercent(progress);
+      sendToAffected(bar);
+    }
+  }
+
+  @Override
+  public @Nullable Collection<Player> getPlayers() {
+    return ImmutableList.copyOf(players);
+  }
+
+  @Override
+  public @NonNull BossBarColor getColor() {
+    return color;
+  }
+
+  @Override
+  public void setColor(@NonNull BossBarColor color) {
+    this.color = checkNotNull(color, "color");
+    if (visible) {
+      sendDivisions(color, overlay);
+    }
+  }
+
+  @Override
+  public @NonNull BossBarOverlay getOverlay() {
+    return overlay;
+  }
+
+  @Override
+  public void setOverlay(@NonNull BossBarOverlay overlay) {
+    this.overlay = checkNotNull(overlay, "overlay");
+    if (visible) {
+      sendDivisions(color, overlay);
+    }
+  }
+
+  private void sendDivisions(BossBarColor color, BossBarOverlay overlay) {
+    BossBar bar = new BossBar();
+    bar.setUuid(uuid);
+    bar.setAction(BossBar.UPDATE_STYLE);
+    bar.setColor(color.ordinal());
+    bar.setOverlay(overlay.ordinal());
+    sendToAffected(bar);
+  }
+
+  @Override
+  public boolean isVisible() {
+    return visible;
+  }
+
+  @Override
+  public void setVisible(boolean visible) {
+    boolean previous = this.visible;
+    if (previous && !visible) {
+      // The bar is being hidden
+      sendToAffected(removePacket());
+    } else if (!previous && visible) {
+      // The bar is being shown
+      sendToAffected(addPacket());
+    }
+    this.visible = visible;
+  }
+
+  @Override
+  public Collection<BossBarFlag> getFlags() {
+    return ImmutableList.copyOf(flags);
+  }
+
+  @Override
+  public void addFlags(BossBarFlag... flags) {
+    if (this.flags.addAll(Arrays.asList(flags)) && visible) {
+      sendToAffected(updateFlags());
+    }
+  }
+
+  @Override
+  public void removeFlag(BossBarFlag flag) {
+    checkNotNull(flag, "flag");
+    if (this.flags.remove(flag) && visible) {
+      sendToAffected(updateFlags());
+    }
+  }
+
+  @Override
+  public void removeFlags(BossBarFlag... flags) {
+    if (this.flags.removeAll(Arrays.asList(flags)) && visible) {
+      sendToAffected(updateFlags());
+    }
+  }
+
+  private short serializeFlags() {
+    short flagMask = 0x0;
+    if (flags.contains(BossBarFlag.DARKEN_SKY)) {
+      flagMask |= 0x1;
+    }
+    if (flags.contains(BossBarFlag.DRAGON_BAR)) {
+      flagMask |= 0x2;
+    }
+    if (flags.contains(BossBarFlag.CREATE_FOG)) {
+      flagMask |= 0x4;
+    }
+    return flagMask;
+  }
+
+  private BossBar addPacket() {
+    BossBar bossBar = new BossBar();
+    bossBar.setUuid(uuid);
+    bossBar.setAction(BossBar.ADD);
+    bossBar.setName(GsonComponentSerializer.INSTANCE.serialize(title));
+    bossBar.setColor(color.ordinal());
+    bossBar.setOverlay(overlay.ordinal());
+    bossBar.setPercent(progress);
+    bossBar.setFlags(serializeFlags());
+    return bossBar;
+  }
+
+  private BossBar removePacket() {
+    BossBar bossBar = new BossBar();
+    bossBar.setUuid(uuid);
+    bossBar.setAction(BossBar.REMOVE);
+    return bossBar;
+  }
+
+  private BossBar updateFlags() {
+    BossBar bossBar = new BossBar();
+    bossBar.setUuid(uuid);
+    bossBar.setAction(BossBar.UPDATE_PROPERTIES);
+    bossBar.setFlags(serializeFlags());
+    return bossBar;
+  }
+
+  private void sendToAffected(MinecraftPacket packet) {
+    for (Player player : players) {
+      if (player.isActive() && player.getProtocolVersion().getProtocol()
+          >= ProtocolVersion.MINECRAFT_1_9.getProtocol()) {
+        sendPacket(player, packet);
+      }
+    }
+  }
+
+  private void sendPacket(Player player, MinecraftPacket packet) {
+    ConnectedPlayer connected = (ConnectedPlayer) player;
+    connected.getMinecraftConnection().write(packet);
+  }
+}