Add PlayerCodeOfConductSendEvent

Enables customizing the code of conduct per send

Author: mbax

paper-api/src/main/java/io/papermc/paper/event/player/PlayerCodeOfConductSendEvent.java

@@ -0,0 +1,65 @@
+package io.papermc.paper.event.player;
+
+import com.google.common.base.Preconditions;
+import io.papermc.paper.connection.PlayerCommonConnection;
+import io.papermc.paper.connection.PlayerConfigurationConnection;
+import org.bukkit.event.Event;
+import org.bukkit.event.HandlerList;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * This event is called when the code of conduct is sent to the player.
+ */
+@ApiStatus.Experimental
+@NullMarked
+public class PlayerCodeOfConductSendEvent extends Event {
+
+    private static final HandlerList HANDLER_LIST = new HandlerList();
+
+    private String codeOfConduct;
+    private final PlayerCommonConnection connection;
+
+    @ApiStatus.Internal
+    public PlayerCodeOfConductSendEvent( final PlayerConfigurationConnection connection, final String codeOfConduct) {
+        this.connection = connection;
+        this.codeOfConduct = codeOfConduct;
+    }
+
+    /**
+     * Gets the connection that will receive the code of conduct.
+     *
+     * @return connection
+     */
+    public PlayerCommonConnection getConnection() {
+        return connection;
+    }
+
+    /**
+     * Gets the code of conduct to be sent.
+     *
+     * @return the code of conduct
+     */
+    public String getCodeOfConduct() {
+        return this.codeOfConduct;
+    }
+
+    /**
+     * Sets the code of conduct to be sent.
+     *
+     * @param codeOfConduct the code of conduct
+     */
+    public void setCodeOfConduct(final String codeOfConduct) {
+        Preconditions.checkArgument(codeOfConduct != null, "Code of Conduct cannot be null");
+        this.codeOfConduct = codeOfConduct;
+    }
+
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLER_LIST;
+    }
+
+    public static HandlerList getHandlerList() {
+        return HANDLER_LIST;
+    }
+}

paper-server/patches/sources/net/minecraft/server/network/ServerConfigurationPacketListenerImpl.java.patch

@@ -71,6 +71,19 @@
          this.configurationTasks.add(this.prepareSpawnTask);
          this.configurationTasks.add(new JoinWorldTask());
          this.startNextTask();
+@@ -120,6 +_,12 @@
+                     string = codeOfConducts.values().iterator().next();
+                 }
+ 
++                // Paper start - Code of Conduct event
++                io.papermc.paper.event.player.PlayerCodeOfConductSendEvent event = new io.papermc.paper.event.player.PlayerCodeOfConductSendEvent(this.paperConnection, string);
++                event.callEvent();
++                string = event.getCodeOfConduct();
++                // Paper end - Code of Conduct event
++
+                 return string;
+             }));
+         }
 @@ -132,12 +_,14 @@
      @Override
      public void handleClientInformation(ServerboundClientInformationPacket packet) {