Properly implement fallback support.

api/src/main/java/com/velocitypowered/api/event/player/KickedFromServerEvent.java

@@ -41,6 +41,25 @@ public final class KickedFromServerEvent implements
     this.result = new Notify(fancyReason);
   }
 
+  /**
+   * Creates a {@code KickedFromServerEvent} instance.
+   * @param player the player affected
+   * @param server the server the player disconnected from
+   * @param originalReason the reason for being kicked, optional
+   * @param duringServerConnect whether or not the player was kicked during the connection process
+   * @param result the initial result
+   */
+  public KickedFromServerEvent(Player player,
+      RegisteredServer server,
+      @Nullable Component originalReason, boolean duringServerConnect,
+      ServerKickResult result) {
+    this.player = Preconditions.checkNotNull(player, "player");
+    this.server = Preconditions.checkNotNull(server, "server");
+    this.originalReason = originalReason;
+    this.duringServerConnect = duringServerConnect;
+    this.result = Preconditions.checkNotNull(result, "result");
+  }
+
   @Override
   public ServerKickResult getResult() {
     return result;

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ConnectedPlayer.java

@@ -7,6 +7,7 @@ import com.velocitypowered.api.event.player.KickedFromServerEvent;
 import com.velocitypowered.api.event.player.KickedFromServerEvent.DisconnectPlayer;
 import com.velocitypowered.api.event.player.KickedFromServerEvent.Notify;
 import com.velocitypowered.api.event.player.KickedFromServerEvent.RedirectPlayer;
+import com.velocitypowered.api.event.player.KickedFromServerEvent.ServerKickResult;
 import com.velocitypowered.api.event.player.PlayerModInfoEvent;
 import com.velocitypowered.api.event.player.PlayerSettingsChangedEvent;
 import com.velocitypowered.api.event.player.ServerPreConnectEvent;
@@ -42,6 +43,7 @@ import com.velocitypowered.proxy.protocol.packet.ResourcePackRequest;
 import com.velocitypowered.proxy.protocol.packet.TitlePacket;
 import com.velocitypowered.proxy.server.VelocityRegisteredServer;
 import com.velocitypowered.proxy.tablist.VelocityTabList;
+import com.velocitypowered.proxy.util.VelocityMessages;
 import io.netty.buffer.ByteBufUtil;
 import java.net.InetSocketAddress;
 import java.util.Collections;
@@ -367,8 +369,23 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
         disconnect(friendlyReason);
       }
     } else {
+      boolean kickedFromCurrent = connectedServer.getServer().equals(rs);
+      ServerKickResult result;
+      if (kickedFromCurrent) {
+        Optional<RegisteredServer> next = getNextServerToTry();
+        result = next.<ServerKickResult>map(RedirectPlayer::create)
+            .orElseGet(() -> DisconnectPlayer.create(friendlyReason));
+      } else {
+        result = Notify.create(friendlyReason);
+      }
       KickedFromServerEvent originalEvent = new KickedFromServerEvent(this, rs, kickReason,
-          !connectedServer.getServer().equals(rs), friendlyReason);
+          !kickedFromCurrent, result);
+      handleKickEvent(originalEvent, friendlyReason);
+    }
+  }
+
+  private void handleKickEvent(KickedFromServerEvent originalEvent,
+      Component friendlyReason) {
     server.getEventManager().fire(originalEvent)
         .thenAcceptAsync(event -> {
           if (event.getResult() instanceof DisconnectPlayer) {
@@ -376,7 +393,15 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
             disconnect(res.getReason());
           } else if (event.getResult() instanceof RedirectPlayer) {
             RedirectPlayer res = (RedirectPlayer) event.getResult();
-              createConnectionRequest(res.getServer()).fireAndForget();
+            createConnectionRequest(res.getServer())
+                .connectWithIndication()
+                .whenCompleteAsync((newResult, exception) -> {
+                  if (newResult == null || !newResult) {
+                    disconnect(friendlyReason);
+                  } else {
+                    sendMessage(VelocityMessages.MOVED_TO_NEW_SERVER);
+                  }
+                }, minecraftConnection.eventLoop());
           } else if (event.getResult() instanceof Notify) {
             Notify res = (Notify) event.getResult();
             if (event.kickedDuringServerConnect()) {
@@ -390,7 +415,6 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
           }
         }, minecraftConnection.eventLoop());
   }
-  }
 
   /**
    * Finds another server to attempt to log into, if we were unexpectedly disconnected from the
@@ -408,14 +432,16 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
       serversToTry = server.getConfiguration().getAttemptConnectionOrder();
     }
 
-    if (tryIndex >= serversToTry.size()) {
-      return Optional.empty();
+    for (; tryIndex < serversToTry.size(); tryIndex++) {
+      String toTryName = serversToTry.get(tryIndex);
+      if (connectedServer != null && toTryName.equals(connectedServer.getServerInfo().getName())) {
+        continue;
       }
 
-    String toTryName = serversToTry.get(tryIndex);
-    tryIndex++;
       return server.getServer(toTryName);
     }
+    return Optional.empty();
+  }
 
   /**
    * Sets the player's new connected server and clears the in-flight connection.

proxy/src/main/java/com/velocitypowered/proxy/util/VelocityMessages.java

@@ -14,6 +14,8 @@ public class VelocityMessages {
       .of("No available servers", TextColor.RED);
   public static final Component ALREADY_CONNECTED = TextComponent
       .of("You are already connected to this proxy!", TextColor.RED);
+  public static final Component MOVED_TO_NEW_SERVER = TextComponent
+      .of("You were moved from the server you were on because you were kicked", TextColor.RED);
 
   private VelocityMessages() {
     throw new AssertionError();