Eliminate ghost thread when all messages deleted in a thread.

Fixes #2262
Closes #2842

// FREEBIE

src/org/thoughtcrime/securesms/ConversationActivity.java

@@ -1168,6 +1168,11 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
     this.composeText.setText(text);
   }
 
+  @Override
+  public void setThreadId(long threadId) {
+    this.threadId = threadId;
+  }
+
   @Override
   public void onAttachmentChanged() {
     initializeSecurity();

src/org/thoughtcrime/securesms/ConversationFragment.java

@@ -212,10 +212,17 @@ public class ConversationFragment extends ListFragment
           @Override
           protected Void doInBackground(MessageRecord... messageRecords) {
             for (MessageRecord messageRecord : messageRecords) {
+              boolean threadDeleted;
+
               if (messageRecord.isMms()) {
-                DatabaseFactory.getMmsDatabase(getActivity()).delete(messageRecord.getId());
+                threadDeleted = DatabaseFactory.getMmsDatabase(getActivity()).delete(messageRecord.getId());
               } else {
-                DatabaseFactory.getSmsDatabase(getActivity()).deleteMessage(messageRecord.getId());
+                threadDeleted = DatabaseFactory.getSmsDatabase(getActivity()).deleteMessage(messageRecord.getId());
+              }
+
+              if (threadDeleted) {
+                threadId = -1;
+                listener.setThreadId(threadId);
               }
             }
 
@@ -297,6 +304,8 @@ public class ConversationFragment extends ListFragment
 
   public interface ConversationFragmentListener {
     public void setComposeText(String text);
+
+    public void setThreadId(long threadId);
   }
 
   public interface SelectionClickListener extends

src/org/thoughtcrime/securesms/database/MmsDatabase.java

@@ -760,7 +760,7 @@ public class MmsDatabase extends MessagingDatabase {
     return messageId;
   }
 
-  public void delete(long messageId) {
+  public boolean delete(long messageId) {
     long threadId                   = getThreadIdForMessage(messageId);
     MmsAddressDatabase addrDatabase = DatabaseFactory.getMmsAddressDatabase(context);
     PartDatabase partDatabase       = DatabaseFactory.getPartDatabase(context);
@@ -769,8 +769,9 @@ public class MmsDatabase extends MessagingDatabase {
 
     SQLiteDatabase database = databaseHelper.getWritableDatabase();
     database.delete(TABLE_NAME, ID_WHERE, new String[] {messageId+""});
-    DatabaseFactory.getThreadDatabase(context).update(threadId);
+    boolean threadDeleted = DatabaseFactory.getThreadDatabase(context).update(threadId);
     notifyConversationListeners(threadId);
+    return threadDeleted;
   }
 
   public void deleteThread(long threadId) {

src/org/thoughtcrime/securesms/database/SmsDatabase.java

@@ -482,13 +482,14 @@ public class SmsDatabase extends MessagingDatabase {
     return cursor;
   }
 
-  public void deleteMessage(long messageId) {
+  public boolean deleteMessage(long messageId) {
     Log.w("MessageDatabase", "Deleting: " + messageId);
     SQLiteDatabase db = databaseHelper.getWritableDatabase();
     long threadId     = getThreadIdForMessage(messageId);
     db.delete(TABLE_NAME, ID_WHERE, new String[] {messageId+""});
-    DatabaseFactory.getThreadDatabase(context).update(threadId);
+    boolean threadDeleted = DatabaseFactory.getThreadDatabase(context).update(threadId);
     notifyConversationListeners(threadId);
+    return threadDeleted;
   }
 
   /*package */void deleteThread(long threadId) {

src/org/thoughtcrime/securesms/database/ThreadDatabase.java

@@ -391,14 +391,14 @@ public class ThreadDatabase extends Database {
     return null;
   }
 
-  public void update(long threadId) {
+  public boolean update(long threadId) {
     MmsSmsDatabase mmsSmsDatabase = DatabaseFactory.getMmsSmsDatabase(context);
     long count                    = mmsSmsDatabase.getConversationCount(threadId);
 
     if (count == 0) {
       deleteThread(threadId);
       notifyConversationListListeners();
-      return;
+      return true;
     }
 
     MmsSmsDatabase.Reader reader = null;
@@ -414,15 +414,17 @@ public class ThreadDatabase extends Database {
         else                 timestamp = record.getDateReceived();
 
         updateThread(threadId, count, record.getBody().getBody(), timestamp, record.getType());
+        notifyConversationListListeners();
+        return false;
       } else {
         deleteThread(threadId);
+        notifyConversationListListeners();
+        return true;
       }
     } finally {
       if (reader != null)
         reader.close();
     }
-
-    notifyConversationListListeners();
   }
 
   public static interface ProgressListener {