ntf server: fix repeat token registration when it became invalid (regression) (#1539)

src/Simplex/Messaging/Notifications/Protocol.hs

@@ -536,6 +536,15 @@ data NtfTknStatus
     NTExpired
   deriving (Eq, Show)
 
+allowTokenVerification :: NtfTknStatus -> Bool
+allowTokenVerification = \case
+  NTNew -> False
+  NTRegistered -> True
+  NTInvalid _ -> False
+  NTConfirmed -> True
+  NTActive -> True
+  NTExpired -> False
+
 allowNtfSubCommands :: NtfTknStatus -> Bool
 allowNtfSubCommands = \case
   NTNew -> False

src/Simplex/Messaging/Notifications/Server.hs

@@ -5,6 +5,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiWayIf #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE NumericUnderscores #-}
 {-# LANGUAGE OverloadedLists #-}
@@ -729,14 +730,17 @@ client NtfServerClient {rcvQ, sndQ} NtfSubscriber {newSubQ, smpAgent = ca} NtfPu
             logDebug "TNEW - registered token"
             let dhSecret = C.dh' dhPubKey tknDhPrivKey
             -- it is required that DH secret is the same, to avoid failed verifications if notification is delaying
-            if tknDhSecret == dhSecret
-              then do
+            if
+              | tknDhSecret /= dhSecret -> pure $ NRErr AUTH
+              | allowTokenVerification tknStatus -> sendVerification
+              | otherwise -> withNtfStore (\st -> updateTknStatus st tkn NTRegistered) $ \_ -> sendVerification
+            where
+              sendVerification = do
                 atomically $ writeTBQueue pushQ (tkn, PNVerification tknRegCode)
                 incNtfStatT token ntfVrfQueued
                 pure $ NRTknId ntfTknId $ C.publicKey tknDhPrivKey
-              else pure $ NRErr AUTH
           TVFY code -- this allows repeated verification for cases when client connection dropped before server response
-            | (tknStatus == NTRegistered || tknStatus == NTConfirmed || tknStatus == NTActive) && tknRegCode == code -> do
+            | allowTokenVerification tknStatus && tknRegCode == code -> do
                 logDebug "TVFY - token verified"
                 withNtfStore (`setTokenActive` tkn) $ \_ -> NROk <$ incNtfStatT token tknVerified
             | otherwise -> do