core, ui: admission message (#5848)

src/Simplex/Chat/Library/Internal.hs

@@ -967,10 +967,17 @@ profileToSendOnAccept user ip = userProfileToSend user (getIncognitoProfile <$>
       ExistingIncognito lp -> fromLocalProfile lp
 
 introduceToModerators :: VersionRangeChat -> User -> GroupInfo -> GroupMember -> CM ()
-introduceToModerators vr user gInfo m = do
+introduceToModerators vr user gInfo@GroupInfo {groupId} m = do
+  when (maxVersion (memberChatVRange m) < groupKnockingVersion) $ sendPendingReviewMessage
   modMs <- withStore' $ \db -> getGroupModerators db vr user gInfo
   let rcpModMs = filter memberCurrent modMs
   introduceMember vr user gInfo m rcpModMs (Just $ MSMember $ memberId' m)
+  where
+    sendPendingReviewMessage = case memberConn m of
+      Just conn -> do
+        let event = XMsgNew $ MCSimple $ extMsgContent (MCText pendingReviewMessage) Nothing
+        sendGroupMemberMessages user conn [event] groupId
+      Nothing -> pure ()
 
 introduceToAll :: VersionRangeChat -> User -> GroupInfo -> GroupMember -> CM ()
 introduceToAll vr user gInfo m = do

src/Simplex/Chat/Library/Subscriber.hs

@@ -796,9 +796,6 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
             when (connChatVersion < batchSend2Version) sendGroupAutoReply
             case mStatus of
               GSMemPendingApproval -> pure ()
-              -- edge case: reviews were turned off mid connection;
-              -- options: proceed to review as declared, or introduce to group and send XGrpLinkAcpt;
-              -- choosing first option for simplicity, same edge case for approval is also not considered
               GSMemPendingReview -> introduceToModerators vr user gInfo' m'
               _ -> do
                 introduceToAll vr user gInfo' m'
@@ -2470,7 +2467,7 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
             pure (announcedMember', Just scopeInfo)
 
     xGrpMemIntro :: GroupInfo -> GroupMember -> MemberInfo -> Maybe MemberRestrictions -> CM ()
-    xGrpMemIntro gInfo@GroupInfo {chatSettings} m@GroupMember {memberRole, localDisplayName = c} memInfo@(MemberInfo memId _ memChatVRange _) memRestrictions = do
+    xGrpMemIntro gInfo@GroupInfo {membership, chatSettings} m@GroupMember {memberRole, localDisplayName = c} memInfo@(MemberInfo memId _ memChatVRange _) memRestrictions = do
       case memberCategory m of
         GCHostMember ->
           withStore' (\db -> runExceptT $ getGroupMemberByMemberId db vr user gInfo memId) >>= \case
@@ -2481,6 +2478,11 @@ processAgentMessageConn vr user@User {userId} corrId agentConnId agentMessage =
                 Nothing -> messageError "x.grp.mem.intro: member chat version range incompatible"
                 Just (ChatVersionRange mcvr)
                   | maxVersion mcvr >= groupDirectInvVersion -> do
+                      memCount <- withStore' $ \db -> getGroupMembersCount db user gInfo
+                      -- only create SGEUserPendingReview item on the first introduction - when only 2 members are user and host
+                      when (memberPending membership && memCount == 2) $ do
+                        (gInfo', m', scopeInfo) <- mkGroupChatScope gInfo m
+                        createInternalChatItem user (CDGroupSnd gInfo' scopeInfo) (CISndGroupEvent SGEUserPendingReview) Nothing
                       subMode <- chatReadVar subscriptionMode
                       -- [async agent commands] commands should be asynchronous, continuation is to send XGrpMemInv - have to remember one has completed and process on second
                       groupConnIds <- createConn subMode

src/Simplex/Chat/Messages/CIContent.hs

@@ -341,6 +341,12 @@ sndGroupEventToText = \case
   SGEMemberDeleted _ p -> "removed " <> profileToText p
   SGEUserLeft -> "left"
   SGEGroupUpdated _ -> "group profile updated"
+  SGEUserPendingReview -> "please wait for group moderators to review your request to join the group"
+
+-- used to send to members with old version
+pendingReviewMessage :: Text
+pendingReviewMessage =
+  "Please wait for group moderators to review your request to join the group."
 
 rcvConnEventToText :: RcvConnEvent -> Text
 rcvConnEventToText = \case

src/Simplex/Chat/Messages/CIContent/Events.hs

@@ -40,6 +40,7 @@ data SndGroupEvent
   | SGEMemberDeleted {groupMemberId :: GroupMemberId, profile :: Profile} -- CRUserDeletedMembers
   | SGEUserLeft -- CRLeftMemberUser
   | SGEGroupUpdated {groupProfile :: GroupProfile} -- CRGroupUpdated
+  | SGEUserPendingReview
   deriving (Show)
 
 data RcvConnEvent

src/Simplex/Chat/Store/Groups.hs

@@ -56,6 +56,7 @@ module Simplex.Chat.Store.Groups
     getGroupMembers,
     getGroupModerators,
     getGroupMembersForExpiration,
+    getGroupMembersCount,
     getGroupCurrentMembersCount,
     deleteGroupChatItems,
     deleteGroupMembers,
@@ -944,6 +945,11 @@ toContactMember :: VersionRangeChat -> User -> (GroupMemberRow :. MaybeConnectio
 toContactMember vr User {userContactId} (memberRow :. connRow) =
   (toGroupMember userContactId memberRow) {activeConn = toMaybeConnection vr connRow}
 
+getGroupMembersCount :: DB.Connection -> User -> GroupInfo -> IO Int
+getGroupMembersCount db User {userId} GroupInfo {groupId} =
+  fromOnly . head
+    <$> DB.query db "SELECT COUNT(1) FROM group_members WHERE group_id = ? AND user_id = ?" (groupId, userId)
+
 getGroupCurrentMembersCount :: DB.Connection -> User -> GroupInfo -> IO Int
 getGroupCurrentMembersCount db User {userId} GroupInfo {groupId} = do
   statuses :: [GroupMemberStatus] <-

src/Simplex/Chat/Store/SQLite/Migrations/chat_query_plans.txt

@@ -5650,6 +5650,10 @@ Query: SELECT COUNT(1) FROM contacts WHERE user_id = ? AND chat_item_ttl > 0
 Plan:
 SEARCH contacts USING INDEX idx_contacts_chat_ts (user_id=?)
 
+Query: SELECT COUNT(1) FROM group_members WHERE group_id = ? AND user_id = ?
+Plan:
+SEARCH group_members USING COVERING INDEX idx_group_members_group_id (user_id=? AND group_id=?)
+
 Query: SELECT COUNT(1) FROM groups WHERE user_id = ? AND chat_item_ttl > 0
 Plan:
 SEARCH groups USING INDEX idx_groups_chat_ts (user_id=?)