Update labels locally

app/src/main/java/eu/faircode/email/Core.java

@@ -708,9 +708,17 @@ class Core {
         ((GmailMessage) imessage).setLabels(new String[]{label}, set);
 
         // Gmail does not push label changes
-        JSONArray fargs = new JSONArray();
-        fargs.put(message.uid);
-        onFetch(context, fargs, folder, istore, ifolder, state);
+
+        List<String> labels = new ArrayList<>();
+        if (message.labels != null)
+            labels.addAll(Arrays.asList(message.labels));
+        labels.remove(label);
+        if (set)
+            labels.add(label);
+
+        DB db = DB.getInstance(context);
+        db.message().setMessageLabels(message.id,
+                DB.Converters.fromStringArray(labels.toArray(new String[0])));
     }
 
     private static void onAdd(Context context, JSONArray jargs, EntityFolder folder, EntityMessage message, IMAPStore istore, IMAPFolder ifolder, State state) throws MessagingException, IOException {

app/src/main/java/eu/faircode/email/DaoMessage.java

@@ -634,6 +634,9 @@ public interface DaoMessage {
     @Query("UPDATE message SET keywords = :keywords WHERE id = :id")
     int setMessageKeywords(long id, String keywords);
 
+    @Query("UPDATE message SET labels = :labels WHERE id = :id")
+    int setMessageLabels(long id, String labels);
+
     @Query("UPDATE message SET ui_seen = :ui_seen WHERE id = :id")
     int setMessageUiSeen(long id, boolean ui_seen);