idea: deal with cookies and transfer

api/src/main/java/org/geysermc/geyser/api/event/bedrock/SessionLoginEvent.java

@@ -32,6 +32,9 @@ import org.geysermc.geyser.api.connection.GeyserConnection;
 import org.geysermc.geyser.api.event.connection.ConnectionEvent;
 import org.geysermc.geyser.api.network.RemoteServer;
 
+import java.util.Map;
+import java.util.Objects;
+
 /**
  * Called when a session has logged in, and is about to connect to a remote java server.
  * This event is cancellable, and can be used to prevent the player from connecting to the remote server.
@@ -40,10 +43,16 @@ public final class SessionLoginEvent extends ConnectionEvent implements Cancella
     private RemoteServer remoteServer;
     private boolean cancelled;
     private String disconnectReason;
+    private Map<String, byte[]> cookies;
+    private boolean transferring;
 
-    public SessionLoginEvent(@NonNull GeyserConnection connection, @NonNull RemoteServer remoteServer) {
+    public SessionLoginEvent(@NonNull GeyserConnection connection,
+                             @NonNull RemoteServer remoteServer,
+                             @NonNull Map<String, byte[]> cookies) {
         super(connection);
         this.remoteServer = remoteServer;
+        this.cookies = cookies;
+        this.transferring = false;
     }
 
     /**
@@ -106,4 +115,36 @@ public final class SessionLoginEvent extends ConnectionEvent implements Cancella
     public void remoteServer(@NonNull RemoteServer remoteServer) {
         this.remoteServer = remoteServer;
     }
+
+    /**
+     * Sets a map of cookies from a possible previous session. The Java server can send and request these
+     * to store information on the client across server transfers.
+     */
+    public void cookies(@NonNull Map<String, byte[]> cookies) {
+        Objects.requireNonNull(cookies);
+        this.cookies = cookies;
+    }
+
+    /**
+     * Gets a map of the sessions cookies, if set.
+     * @return the connections cookies
+     */
+    public @NonNull Map<String, byte[]> cookies() {
+        return cookies;
+    }
+
+    /**
+     * Determines the connection intent of the connection
+     */
+    public void transferring(boolean transferring) {
+        this.transferring = transferring;
+    }
+
+    /**
+     * Gets whether this login attempt to the Java server
+     * has the transfer intent
+     */
+    public boolean transferring() {
+        return this.transferring;
+    }
 }

api/src/main/java/org/geysermc/geyser/api/event/java/ServerTransferEvent.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2019-2024 GeyserMC. http://geysermc.org
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @author GeyserMC
+ * @link https://github.com/GeyserMC/Geyser
+ */
+
+package org.geysermc.geyser.api.event.java;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.geysermc.geyser.api.connection.GeyserConnection;
+import org.geysermc.geyser.api.event.connection.ConnectionEvent;
+
+import java.util.Map;
+
+public class ServerTransferEvent extends ConnectionEvent {
+
+    private final String host;
+    private final int port;
+    private final Map<String, byte[]> cookies;
+
+    public ServerTransferEvent(@NonNull GeyserConnection connection, String host, int port, Map<String, byte[]> cookies) {
+        super(connection);
+        this.host = host;
+        this.port = port;
+        this.cookies = cookies;
+    }
+
+    /**
+     * The host that the Java server requests a transfer to.
+     * @return the host
+     */
+    public String host() {
+        return this.host;
+    }
+
+    /**
+     * The port that the Java server requests a transfer to.
+     * @return the port
+     */
+    public int port() {
+        return this.port;
+    }
+
+    /**
+     * Gets a map of the sessions current cookies.
+     * @return the connections cookies
+     */
+    public @NonNull Map<String, byte[]> cookies() {
+        return cookies;
+    }
+
+}