From af865b77ad00273b748e0392322f336166af07f7 Mon Sep 17 00:00:00 2001
From: delvh <dev.lh@web.de>
Date: Sun, 2 Feb 2020 13:34:28 +0100
Subject: [PATCH] Added status update for when a client goes offline

---
 .../java/envoy/server/ConnectionManager.java  | 19 ++++++++
 .../processors/LoginCredentialProcessor.java  |  3 +-
 .../processors/UserStatusChangeProcessor.java | 44 ++++++++++++-------
 3 files changed, 49 insertions(+), 17 deletions(-)

diff --git a/src/main/java/envoy/server/ConnectionManager.java b/src/main/java/envoy/server/ConnectionManager.java
index ffc64e1..2d7aac5 100644
--- a/src/main/java/envoy/server/ConnectionManager.java
+++ b/src/main/java/envoy/server/ConnectionManager.java
@@ -7,6 +7,11 @@ import java.util.Set;
 
 import com.jenkov.nioserver.ISocketIdListener;
 
+import envoy.data.User;
+import envoy.event.UserStatusChangeEvent;
+import envoy.server.database.PersistenceManager;
+import envoy.server.processors.UserStatusChangeProcessor;
+
 /**
  * Project: <strong>envoy-server-standalone</strong><br>
  * File: <strong>ConnectionManager.java</strong><br>
@@ -44,6 +49,11 @@ public class ConnectionManager implements ISocketIdListener {
 
 	@Override
 	public void socketCancelled(long socketId) {
+		// notifying contacts of this users offline-going
+		long	clientId	= getUserIdBySocketId(socketId);
+		User	user		= new User(clientId, PersistenceManager.getPersistenceManager().getUserById(clientId).getName());
+		UserStatusChangeProcessor.updateUserStatus(new UserStatusChangeEvent(user));
+		// removing the socket
 		if (!pendingSockets.remove(socketId))
 			sockets.entrySet().stream().filter(e -> e.getValue() == socketId).forEach(e -> sockets.remove(e.getValue()));
 	}
@@ -70,6 +80,15 @@ public class ConnectionManager implements ISocketIdListener {
 	 */
 	public long getSocketId(long userId) { return sockets.get(userId); }
 
+	/**
+	 * @param socketId the id of the socket whose User is needed
+	 * @return the userId associated with this socketId
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
+	public long getUserIdBySocketId(long socketId) {
+		return sockets.entrySet().stream().filter((entry) -> entry.getValue().equals(socketId)).findFirst().get().getKey();
+	}
+
 	/**
 	 * @param userId the ID of the user to check for
 	 * @return {@code true} if the user is online
diff --git a/src/main/java/envoy/server/processors/LoginCredentialProcessor.java b/src/main/java/envoy/server/processors/LoginCredentialProcessor.java
index 274d6fd..f0373f3 100644
--- a/src/main/java/envoy/server/processors/LoginCredentialProcessor.java
+++ b/src/main/java/envoy/server/processors/LoginCredentialProcessor.java
@@ -37,6 +37,7 @@ public class LoginCredentialProcessor implements ObjectProcessor<LoginCredential
 
 	@Override
 	public void process(LoginCredentials input, long socketId, ObjectWriteProxy writeProxy) throws IOException {
+		UserStatusChangeProcessor.setWriteProxy(writeProxy);
 		System.out.println(String.format("Received login credentials %s from socket ID %d", input, socketId));
 
 		envoy.server.data.User user = getUser(input);
@@ -45,7 +46,7 @@ public class LoginCredentialProcessor implements ObjectProcessor<LoginCredential
 		if (user == null) return;
 		// notifies contacts of this users online-going and updates his status in the
 		// database
-		UserStatusChangeProcessor.updateUserStatus(new UserStatusChangeEvent(user.toCommonUser()), writeProxy);
+		UserStatusChangeProcessor.updateUserStatus(new UserStatusChangeEvent(user.toCommonUser()));
 
 		ConnectionManager.getInstance().registerUser(user.getId(), socketId);
 
diff --git a/src/main/java/envoy/server/processors/UserStatusChangeProcessor.java b/src/main/java/envoy/server/processors/UserStatusChangeProcessor.java
index 8a43556..30b225a 100644
--- a/src/main/java/envoy/server/processors/UserStatusChangeProcessor.java
+++ b/src/main/java/envoy/server/processors/UserStatusChangeProcessor.java
@@ -22,19 +22,20 @@ import envoy.server.net.ObjectWriteProxy;
  */
 public class UserStatusChangeProcessor implements ObjectProcessor<UserStatusChangeEvent> {
 
+	private static ObjectWriteProxy writeProxy;
+
 	@Override
 	public Class<UserStatusChangeEvent> getInputClass() { return UserStatusChangeEvent.class; }
 
 	@Override
 	public void process(UserStatusChangeEvent input, long socketId, ObjectWriteProxy writeProxy) throws IOException {
-
 		PersistenceManager perMan = PersistenceManager.getPersistenceManager();
 		// new status should not equal old status
 		if (input.get().equals(perMan.getUserById(input.getId()).getStatus())) {
 			System.out.println("Received an unnecessary UserStatusChangeEvent");
 			return;
 		}
-		updateUserStatus(input, writeProxy);
+		updateUserStatus(input);
 
 	}
 
@@ -42,37 +43,48 @@ public class UserStatusChangeProcessor implements ObjectProcessor<UserStatusChan
 	 * Sets the {@link UserStatus} for a given user. Both offline contacts and
 	 * currently online contacts are notified.
 	 *
-	 * @param evt        the {@link UserStatusChangeEvent} that signals the change
-	 * @param writeProxy the {@link ObjectWriteProxy} that is used to send objects
-	 *                   back to clients
-	 * @throws IOException if sending this update failed for any contact
+	 * @param evt the {@link UserStatusChangeEvent} that signals the change
 	 * @since Envoy Server Standalone v0.1-alpha
 	 */
-	public static void updateUserStatus(UserStatusChangeEvent evt, ObjectWriteProxy writeProxy) throws IOException {
+	public static void updateUserStatus(UserStatusChangeEvent evt) {
+		// handling for newly logged in clients
 		PersistenceManager		perMan	= PersistenceManager.getPersistenceManager();
 		envoy.server.data.User	user	= perMan.getUserById(evt.getId());
-		// handling for newly logged in clients
 		perMan.updateUserStatus(user, evt.get());
 
 		// handling for contacts that are already online
-		notifyContacts(evt, user, writeProxy);
+		notifyContacts(evt, user);
 	}
 
 	/**
 	 * notifies active contacts of this {@link User} that his {@link UserStatus} has
 	 * changed
 	 *
-	 * @param evt        the {@link UserStatusChangeEvent} to send to other clients
-	 * @param user       the {@link User}
-	 * @param writeProxy the {@link ObjectWriteProxy} that is used to send objects
-	 *                   back to clients
+	 * @param evt  the {@link UserStatusChangeEvent} to send to other clients
+	 * @param user the {@link User}
 	 * @throws IOException if sending this update failed for any contact
 	 * @since Envoy Server Standalone v0.1-alpha
 	 */
-	public static void notifyContacts(UserStatusChangeEvent evt, envoy.server.data.User user, ObjectWriteProxy writeProxy) throws IOException {
+	private static void notifyContacts(UserStatusChangeEvent evt, envoy.server.data.User user) {
 		ConnectionManager conMan = ConnectionManager.getInstance();
-		for (User contact : user.getContacts())
-			if (conMan.isOnline(contact.getId())) writeProxy.write(conMan.getSocketId(contact.getId()), evt);
+		try {
+			for (User contact : user.getContacts())
+				if (conMan.isOnline(contact.getId())) writeProxy.write(conMan.getSocketId(contact.getId()), evt);
+		} catch (IOException e) {
+			e.printStackTrace();
+			System.err.println("Could not notify online contacts of user" + evt.getId() + "that his status changed");
+		}
 	}
 
+	/**
+	 * This method is only called by the LoginCredentialProcessor because every
+	 * user needs to login (open a socket) before changing his status.
+	 * Needed to ensure propagation of events because an uninitialised writeProxy
+	 * would cause problems.
+	 *
+	 * @param writeProxy the writeProxy that is used to send objects back to clients
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
+	public static void setWriteProxy(ObjectWriteProxy writeProxy) { UserStatusChangeProcessor.writeProxy = writeProxy; }
+
 }
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