Introduce client layer events for forums

The forum UI depended on sync layer events such as MessageStateChangedEvent.
Now, the forum client broadcasts its own high-level event (`ForumPostReceivedEvent`)
with the information the UI needs (`ForumPostHeader`).

Closes #310

briar-core/src/org/briarproject/clients/MessageTreeImpl.java

@@ -14,8 +14,9 @@ import java.util.Map;
 public class MessageTreeImpl<T extends MessageTree.MessageNode>
 		implements MessageTree<T> {
 
-	Map<MessageId, List<T>> nodeMap = new HashMap<MessageId, List<T>>();
-	List<T> roots = new ArrayList<T>();
+	private final Map<MessageId, List<T>> nodeMap = new HashMap<MessageId, List<T>>();
+	private final List<T> roots = new ArrayList<T>();
+	private final List<List<T>> unsortedLists = new ArrayList<List<T>>();
 
 	private Comparator<T> comparator = new Comparator<T>() {
 		@Override
@@ -38,26 +39,44 @@ public class MessageTreeImpl<T extends MessageTree.MessageNode>
 		}
 		// parse the nodes for dependencies
 		for (T node : nodes) {
-			if (node.getParentId() == null) {
-				roots.add(node);
-			}
-			else {
-				// retrieve the parent's children
-				List<T> pChildren = nodeMap.get(node.getParentId());
-				pChildren.add(node);
-			}
+			parseNode(node);
 		}
-		sortAll();
+		sortUnsorted();
 	}
 
-	private void sortAll() {
-		Collections.sort(roots, comparator);
-		// Sort all the sub-lists
-		for (Map.Entry<MessageId, List<T>> entry: nodeMap.entrySet()) {
-			Collections.sort(entry.getValue(), comparator);
+	@Override
+	public void add(T node) {
+		add(Collections.singletonList(node));
+	}
+
+	private void markAsUnsorted(List<T> list) {
+		if (!unsortedLists.contains(list))
+			unsortedLists.add(list);
+	}
+
+	private void parseNode(T node) {
+		if (node.getParentId() == null) {
+			roots.add(node);
+			markAsUnsorted(roots);
+		} else {
+			// retrieve the parent's children
+			List<T> pChildren = nodeMap.get(node.getParentId());
+			pChildren.add(node);
+			markAsUnsorted(pChildren);
 		}
 	}
 
+	private void sortUnsorted() {
+		// leave unsorted if there is no comparator
+		if (comparator != null) {
+			for (List<T> list : unsortedLists) {
+				Collections.sort(list, comparator);
+			}
+			unsortedLists.clear();
+		}
+	}
+
+
 	private void traverse(List<T> list, T node) {
 		list.add(node);
 		for (T child : nodeMap.get(node.getId())) {
@@ -65,6 +84,16 @@ public class MessageTreeImpl<T extends MessageTree.MessageNode>
 		}
 	}
 
+	@Override
+	public void setComparator(Comparator<T> comparator) {
+		this.comparator = comparator;
+		// Sort all lists with the new comparator
+		Collections.sort(roots, comparator);
+		for (Map.Entry<MessageId, List<T>> entry: nodeMap.entrySet()) {
+			Collections.sort(entry.getValue(), comparator);
+		}
+	}
+
 	@Override
 	public Collection<T> depthFirstOrder() {
 		List<T> orderedList = new ArrayList<T>();
@@ -74,9 +103,4 @@ public class MessageTreeImpl<T extends MessageTree.MessageNode>
 		return Collections.unmodifiableList(orderedList);
 	}
 
-	@Override
-	public void setComparator(Comparator<T> comparator) {
-		this.comparator = comparator;
-	}
-
 }

briar-core/src/org/briarproject/forum/ForumManagerImpl.java

@@ -4,9 +4,11 @@ import org.briarproject.api.FormatException;
 import org.briarproject.api.clients.ClientHelper;
 import org.briarproject.api.data.BdfDictionary;
 import org.briarproject.api.data.BdfList;
+import org.briarproject.api.data.MetadataParser;
 import org.briarproject.api.db.DatabaseComponent;
 import org.briarproject.api.db.DbException;
 import org.briarproject.api.db.Transaction;
+import org.briarproject.api.event.ForumPostReceivedEvent;
 import org.briarproject.api.forum.Forum;
 import org.briarproject.api.forum.ForumFactory;
 import org.briarproject.api.forum.ForumManager;
@@ -19,7 +21,9 @@ import org.briarproject.api.identity.IdentityManager;
 import org.briarproject.api.sync.ClientId;
 import org.briarproject.api.sync.Group;
 import org.briarproject.api.sync.GroupId;
+import org.briarproject.api.sync.Message;
 import org.briarproject.api.sync.MessageId;
+import org.briarproject.clients.BdfIncomingMessageHook;
 import org.briarproject.util.StringUtils;
 
 import java.util.ArrayList;
@@ -44,7 +48,7 @@ import static org.briarproject.api.forum.ForumConstants.KEY_READ;
 import static org.briarproject.api.forum.ForumConstants.KEY_TIMESTAMP;
 import static org.briarproject.api.identity.Author.Status.ANONYMOUS;
 
-class ForumManagerImpl implements ForumManager {
+class ForumManagerImpl extends BdfIncomingMessageHook implements ForumManager {
 
 	private static final Logger LOG =
 			Logger.getLogger(ForumManagerImpl.class.getName());
@@ -55,21 +59,31 @@ class ForumManagerImpl implements ForumManager {
 
 	private final DatabaseComponent db;
 	private final IdentityManager identityManager;
-	private final ClientHelper clientHelper;
 	private final ForumFactory forumFactory;
 	private final List<RemoveForumHook> removeHooks;
 
 	@Inject
 	ForumManagerImpl(DatabaseComponent db, IdentityManager identityManager,
-			ClientHelper clientHelper, ForumFactory forumFactory) {
+			ClientHelper clientHelper, MetadataParser metadataParser,
+			ForumFactory forumFactory) {
 
+		super(clientHelper, metadataParser);
 		this.db = db;
 		this.identityManager = identityManager;
-		this.clientHelper = clientHelper;
 		this.forumFactory = forumFactory;
 		removeHooks = new CopyOnWriteArrayList<RemoveForumHook>();
 	}
 
+	@Override
+	protected void incomingMessage(Transaction txn, Message m, BdfList body,
+			BdfDictionary meta) throws DbException, FormatException {
+
+		ForumPostHeader post = getForumPostHeader(txn, m.getId(), meta);
+		ForumPostReceivedEvent event =
+				new ForumPostReceivedEvent(post, m.getGroupId());
+		txn.attach(event);
+	}
+
 	@Override
 	public ClientId getClientId() {
 		return CLIENT_ID;
@@ -193,25 +207,7 @@ class ForumManagerImpl implements ForumManager {
 		for (Entry<MessageId, BdfDictionary> entry : metadata.entrySet()) {
 			try {
 				BdfDictionary meta = entry.getValue();
-				long timestamp = meta.getLong(KEY_TIMESTAMP);
-				Author author = null;
-				Status authorStatus = ANONYMOUS;
-				MessageId parentId = null;
-				if (meta.containsKey(KEY_PARENT))
-					parentId = new MessageId(meta.getRaw(KEY_PARENT));
-				BdfDictionary d1 = meta.getDictionary(KEY_AUTHOR, null);
-				if (d1 != null) {
-					AuthorId authorId = new AuthorId(d1.getRaw(KEY_ID));
-					String name = d1.getString(KEY_NAME);
-					byte[] publicKey = d1.getRaw(KEY_PUBLIC_NAME);
-					author = new Author(authorId, name, publicKey);
-					authorStatus =
-							identityManager.getAuthorStatus(author.getId());
-				}
-				String contentType = meta.getString(KEY_CONTENT_TYPE);
-				boolean read = meta.getBoolean(KEY_READ);
-				headers.add(new ForumPostHeader(entry.getKey(), parentId,
-						timestamp, author, authorStatus, contentType, read));
+				headers.add(getForumPostHeader(entry.getKey(), meta));
 			} catch (FormatException e) {
 				throw new DbException(e);
 			}
@@ -242,4 +238,39 @@ class ForumManagerImpl implements ForumManager {
 		return new Forum(g, forum.getString(0), forum.getRaw(1));
 	}
 
+	private ForumPostHeader getForumPostHeader(Transaction txn, MessageId id,
+			BdfDictionary meta) throws DbException, FormatException {
+
+		long timestamp = meta.getLong(KEY_TIMESTAMP);
+		Author author = null;
+		Status authorStatus = ANONYMOUS;
+		MessageId parentId = null;
+		if (meta.containsKey(KEY_PARENT))
+			parentId = new MessageId(meta.getRaw(KEY_PARENT));
+		BdfDictionary d1 = meta.getDictionary(KEY_AUTHOR, null);
+		if (d1 != null) {
+			AuthorId authorId = new AuthorId(d1.getRaw(KEY_ID));
+			String name = d1.getString(KEY_NAME);
+			byte[] publicKey = d1.getRaw(KEY_PUBLIC_NAME);
+			author = new Author(authorId, name, publicKey);
+			if (txn == null) {
+				authorStatus = identityManager.getAuthorStatus(author.getId());
+			} else {
+				authorStatus =
+						identityManager.getAuthorStatus(txn, author.getId());
+			}
+		}
+		String contentType = meta.getString(KEY_CONTENT_TYPE);
+		boolean read = meta.getBoolean(KEY_READ);
+
+		return new ForumPostHeader(id, parentId, timestamp, author,
+				authorStatus, contentType, read);
+	}
+
+	private ForumPostHeader getForumPostHeader(MessageId id,
+			BdfDictionary meta) throws DbException, FormatException {
+
+		return getForumPostHeader(null, id, meta);
+	}
+
 }

briar-core/src/org/briarproject/forum/ForumModule.java

@@ -29,7 +29,13 @@ public class ForumModule {
 
 	@Provides
 	@Singleton
-	ForumManager provideForumManager(ForumManagerImpl forumManager) {
+	ForumManager provideForumManager(ForumManagerImpl forumManager,
+			ValidationManager validationManager) {
+
+		validationManager
+				.registerIncomingMessageHook(forumManager.getClientId(),
+						forumManager);
+
 		return forumManager;
 	}