core: member mentions, types and rfc (#5555)

* core: member mentions, types and rfc

* update

* update rfc

* save/get mentions (WIP)

* markdown

* store received mentions and userMention flag

* sent mentions

* update message with mentions

* db queries

* CLI mentions, test passes

* use maps for mentions

* tests

* comment

* save mentions on sent messages

* postresql schema

* refactor

* M.empty

* include both displayName and localAlias into MentionedMemberInfo

* fix saving sent mentions

* include mentions in previews

* update plans

src/Simplex/Chat/Store/Groups.hs

@@ -47,6 +47,8 @@ module Simplex.Chat.Store.Groups
     getActiveMembersByName,
     getGroupInfoByName,
     getGroupMember,
+    getMentionedGroupMember,
+    getMentionedMemberByMemberId,
     getGroupMemberById,
     getGroupMemberByMemberId,
     getGroupMembers,
@@ -148,7 +150,7 @@ import Data.Ord (Down (..))
 import Data.Text (Text)
 import Data.Time.Clock (UTCTime (..), getCurrentTime)
 import Simplex.Chat.Messages
-import Simplex.Chat.Protocol (groupForwardVersion)
+import Simplex.Chat.Protocol (MemberMention (..), groupForwardVersion)
 import Simplex.Chat.Store.Direct
 import Simplex.Chat.Store.Shared
 import Simplex.Chat.Types
@@ -798,6 +800,37 @@ getGroupMember db vr user@User {userId} groupId groupMemberId =
       (groupMemberQuery <> " WHERE m.group_id = ? AND m.group_member_id = ? AND m.user_id = ?")
       (userId, groupId, groupMemberId, userId)
 
+getMentionedGroupMember :: DB.Connection -> User -> GroupId -> GroupMemberId -> ExceptT StoreError IO MentionedMember
+getMentionedGroupMember db User {userId} groupId gmId =
+  ExceptT $ firstRow toMentionedMember (SEGroupMemberNotFound gmId) $
+    DB.query
+      db
+      (mentionedMemberQuery <> " WHERE m.group_id = ? AND m.group_member_id = ? AND m.user_id = ?")
+      (groupId, gmId, userId)
+
+getMentionedMemberByMemberId :: DB.Connection -> User -> GroupId -> MemberMention -> IO MentionedMember
+getMentionedMemberByMemberId db User {userId} groupId MemberMention {memberId} =
+  fmap (fromMaybe mentionedMember) $ maybeFirstRow toMentionedMember $
+    DB.query
+      db
+      (mentionedMemberQuery <> " WHERE m.group_id = ? AND m.member_id = ? AND m.user_id = ?")
+      (groupId, memberId, userId)
+  where
+    mentionedMember = MentionedMember {memberId, memberRef = Nothing}
+
+mentionedMemberQuery :: Query
+mentionedMemberQuery =
+  [sql|
+    SELECT m.group_member_id, m.member_id, m.member_role, p.display_name, p.local_alias
+    FROM group_members m
+    JOIN contact_profiles p ON p.contact_profile_id = COALESCE(m.member_profile_id, m.contact_profile_id)
+  |]
+
+toMentionedMember :: (GroupMemberId, MemberId, GroupMemberRole, Text, Maybe Text) -> MentionedMember
+toMentionedMember (groupMemberId, memberId, memberRole, displayName, localAlias) =
+  let memberRef = Just MentionedMemberInfo {groupMemberId, displayName, localAlias, memberRole}
+   in MentionedMember {memberId, memberRef}
+
 getGroupMemberById :: DB.Connection -> VersionRangeChat -> User -> GroupMemberId -> ExceptT StoreError IO GroupMember
 getGroupMemberById db vr user@User {userId} groupMemberId =
   ExceptT . firstRow (toContactMember vr user) (SEGroupMemberNotFound groupMemberId) $

src/Simplex/Chat/Store/Messages.hs

@@ -53,6 +53,8 @@ module Simplex.Chat.Store.Messages
     markDirectChatItemDeleted,
     updateGroupChatItemStatus,
     updateGroupChatItem,
+    createGroupCIMentions,
+    updateGroupCIMentions,
     deleteGroupChatItem,
     updateGroupChatItemModerated,
     updateGroupCIBlockedByAdmin,
@@ -136,6 +138,8 @@ import Data.Int (Int64)
 import Data.List (sortBy)
 import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as L
+import Data.Map.Strict (Map)
+import qualified Data.Map.Strict as M
 import Data.Maybe (catMaybes, fromMaybe, isJust, mapMaybe)
 import Data.Ord (Down (..), comparing)
 import Data.Text (Text)
@@ -152,6 +156,7 @@ import Simplex.Chat.Store.Groups
 import Simplex.Chat.Store.NoteFolders
 import Simplex.Chat.Store.Shared
 import Simplex.Chat.Types
+import Simplex.Chat.Types.Shared
 import Simplex.Messaging.Agent.Protocol (AgentMsgId, ConnId, MsgMeta (..), UserId)
 import Simplex.Messaging.Agent.Store.AgentStore (firstRow, firstRow', maybeFirstRow)
 import Simplex.Messaging.Agent.Store.DB (BoolInt (..))
@@ -367,7 +372,7 @@ updateChatTs db User {userId} chatDirection chatTs = case toChatInfo chatDirecti
 
 createNewSndChatItem :: DB.Connection -> User -> ChatDirection c 'MDSnd -> SndMessage -> CIContent 'MDSnd -> Maybe (CIQuote c) -> Maybe CIForwardedFrom -> Maybe CITimed -> Bool -> UTCTime -> IO ChatItemId
 createNewSndChatItem db user chatDirection SndMessage {msgId, sharedMsgId} ciContent quotedItem itemForwarded timed live createdAt =
-  createNewChatItem_ db user chatDirection createdByMsgId (Just sharedMsgId) ciContent quoteRow itemForwarded timed live createdAt Nothing createdAt
+  createNewChatItem_ db user chatDirection createdByMsgId (Just sharedMsgId) ciContent quoteRow itemForwarded timed live False createdAt Nothing createdAt
   where
     createdByMsgId = if msgId == 0 then Nothing else Just msgId
     quoteRow :: NewQuoteRow
@@ -381,9 +386,9 @@ createNewSndChatItem db user chatDirection SndMessage {msgId, sharedMsgId} ciCon
           CIQGroupRcv (Just GroupMember {memberId}) -> (Just False, Just memberId)
           CIQGroupRcv Nothing -> (Just False, Nothing)
 
-createNewRcvChatItem :: ChatTypeQuotable c => DB.Connection -> User -> ChatDirection c 'MDRcv -> RcvMessage -> Maybe SharedMsgId -> CIContent 'MDRcv -> Maybe CITimed -> Bool -> UTCTime -> UTCTime -> IO (ChatItemId, Maybe (CIQuote c), Maybe CIForwardedFrom)
-createNewRcvChatItem db user chatDirection RcvMessage {msgId, chatMsgEvent, forwardedByMember} sharedMsgId_ ciContent timed live itemTs createdAt = do
-  ciId <- createNewChatItem_ db user chatDirection (Just msgId) sharedMsgId_ ciContent quoteRow itemForwarded timed live itemTs forwardedByMember createdAt
+createNewRcvChatItem :: ChatTypeQuotable c => DB.Connection -> User -> ChatDirection c 'MDRcv -> RcvMessage -> Maybe SharedMsgId -> CIContent 'MDRcv -> Maybe CITimed -> Bool -> Bool -> UTCTime -> UTCTime -> IO (ChatItemId, Maybe (CIQuote c), Maybe CIForwardedFrom)
+createNewRcvChatItem db user chatDirection RcvMessage {msgId, chatMsgEvent, forwardedByMember} sharedMsgId_ ciContent timed live userMention itemTs createdAt = do
+  ciId <- createNewChatItem_ db user chatDirection (Just msgId) sharedMsgId_ ciContent quoteRow itemForwarded timed live userMention itemTs forwardedByMember createdAt
   quotedItem <- mapM (getChatItemQuote_ db user chatDirection) quotedMsg
   pure (ciId, quotedItem, itemForwarded)
   where
@@ -400,13 +405,13 @@ createNewRcvChatItem db user chatDirection RcvMessage {msgId, chatMsgEvent, forw
 
 createNewChatItemNoMsg :: forall c d. MsgDirectionI d => DB.Connection -> User -> ChatDirection c d -> CIContent d -> UTCTime -> UTCTime -> IO ChatItemId
 createNewChatItemNoMsg db user chatDirection ciContent itemTs =
-  createNewChatItem_ db user chatDirection Nothing Nothing ciContent quoteRow Nothing Nothing False itemTs Nothing
+  createNewChatItem_ db user chatDirection Nothing Nothing ciContent quoteRow Nothing Nothing False False itemTs Nothing
   where
     quoteRow :: NewQuoteRow
     quoteRow = (Nothing, Nothing, Nothing, Nothing, Nothing)
 
-createNewChatItem_ :: forall c d. MsgDirectionI d => DB.Connection -> User -> ChatDirection c d -> Maybe MessageId -> Maybe SharedMsgId -> CIContent d -> NewQuoteRow -> Maybe CIForwardedFrom -> Maybe CITimed -> Bool -> UTCTime -> Maybe GroupMemberId -> UTCTime -> IO ChatItemId
-createNewChatItem_ db User {userId} chatDirection msgId_ sharedMsgId ciContent quoteRow itemForwarded timed live itemTs forwardedByMember createdAt = do
+createNewChatItem_ :: forall c d. MsgDirectionI d => DB.Connection -> User -> ChatDirection c d -> Maybe MessageId -> Maybe SharedMsgId -> CIContent d -> NewQuoteRow -> Maybe CIForwardedFrom -> Maybe CITimed -> Bool -> Bool -> UTCTime -> Maybe GroupMemberId -> UTCTime -> IO ChatItemId
+createNewChatItem_ db User {userId} chatDirection msgId_ sharedMsgId ciContent quoteRow itemForwarded timed live userMention itemTs forwardedByMember createdAt = do
   DB.execute
     db
     [sql|
@@ -415,20 +420,20 @@ createNewChatItem_ db User {userId} chatDirection msgId_ sharedMsgId ciContent q
         user_id, created_by_msg_id, contact_id, group_id, group_member_id, note_folder_id,
         -- meta
         item_sent, item_ts, item_content, item_content_tag, item_text, item_status, msg_content_tag, shared_msg_id,
-        forwarded_by_group_member_id, include_in_history, created_at, updated_at, item_live, timed_ttl, timed_delete_at,
+        forwarded_by_group_member_id, include_in_history, created_at, updated_at, item_live, user_mention, timed_ttl, timed_delete_at,
         -- quote
         quoted_shared_msg_id, quoted_sent_at, quoted_content, quoted_sent, quoted_member_id,
         -- forwarded from
         fwd_from_tag, fwd_from_chat_name, fwd_from_msg_dir, fwd_from_contact_id, fwd_from_group_id, fwd_from_chat_item_id
-      ) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
+      ) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
     |]
     ((userId, msgId_) :. idsRow :. itemRow :. quoteRow' :. forwardedFromRow)
   ciId <- insertedRowId db
   forM_ msgId_ $ \msgId -> insertChatItemMessage_ db ciId msgId createdAt
   pure ciId
   where
-    itemRow :: (SMsgDirection d, UTCTime, CIContent d, Text, Text, CIStatus d, Maybe MsgContentTag, Maybe SharedMsgId, Maybe GroupMemberId, BoolInt) :. (UTCTime, UTCTime, Maybe BoolInt) :. (Maybe Int, Maybe UTCTime)
-    itemRow = (msgDirection @d, itemTs, ciContent, toCIContentTag ciContent, ciContentToText ciContent, ciCreateStatus ciContent, msgContentTag <$> ciMsgContent ciContent, sharedMsgId, forwardedByMember, BI includeInHistory) :. (createdAt, createdAt, BI <$> (justTrue live)) :. ciTimedRow timed
+    itemRow :: (SMsgDirection d, UTCTime, CIContent d, Text, Text, CIStatus d, Maybe MsgContentTag, Maybe SharedMsgId, Maybe GroupMemberId, BoolInt) :. (UTCTime, UTCTime, Maybe BoolInt, BoolInt) :. (Maybe Int, Maybe UTCTime)
+    itemRow = (msgDirection @d, itemTs, ciContent, toCIContentTag ciContent, ciContentToText ciContent, ciCreateStatus ciContent, msgContentTag <$> ciMsgContent ciContent, sharedMsgId, forwardedByMember, BI includeInHistory) :. (createdAt, createdAt, BI <$> (justTrue live), BI userMention) :. ciTimedRow timed
     quoteRow' = let (a, b, c, d, e) = quoteRow in (a, b, c, BI <$> d, e)
     idsRow :: (Maybe Int64, Maybe Int64, Maybe Int64, Maybe Int64)
     idsRow = case chatDirection of
@@ -766,7 +771,7 @@ getGroupChatPreview_ :: DB.Connection -> VersionRangeChat -> User -> ChatPreview
 getGroupChatPreview_ db vr user (GroupChatPD _ groupId lastItemId_ stats) = do
   groupInfo <- getGroupInfo db vr user groupId
   lastItem <- case lastItemId_ of
-    Just lastItemId -> (: []) <$> getGroupChatItem db user groupId lastItemId
+    Just lastItemId -> (: []) <$> getGroupCIWithReactions db user groupInfo lastItemId
     Nothing -> pure []
   pure $ AChat SCTGroup (Chat (GroupChat groupInfo) lastItem stats)
 
@@ -855,7 +860,7 @@ getLocalChatPreview_ db user (LocalChatPD _ noteFolderId lastItemId_ stats) = do
 
 -- this function can be changed so it never fails, not only avoid failure on invalid json
 toLocalChatItem :: UTCTime -> ChatItemRow -> Either StoreError (CChatItem 'CTLocal)
-toLocalChatItem currentTs ((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) =
+toLocalChatItem currentTs ((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive, BI userMention) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) =
   chatItem $ fromRight invalid $ dbParseACIContent itemContentText
   where
     invalid = ACIContent msgDir $ CIInvalidJSON itemContentText
@@ -879,7 +884,7 @@ toLocalChatItem currentTs ((itemId, itemTs, AMsgDirection msgDir, itemContentTex
         _ -> Nothing
     cItem :: MsgDirectionI d => SMsgDirection d -> CIDirection 'CTLocal d -> CIStatus d -> CIContent d -> Maybe (CIFile d) -> CChatItem 'CTLocal
     cItem d chatDir ciStatus content file =
-      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, formattedText = parseMaybeMarkdownList itemText, quotedItem = Nothing, reactions = [], file}
+      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, mentions = M.empty, formattedText = parseMaybeMarkdownList itemText, quotedItem = Nothing, reactions = [], file}
     badItem = Left $ SEBadChatItem itemId (Just itemTs)
     ciMeta :: CIContent d -> CIStatus d -> CIMeta 'CTLocal d
     ciMeta content status =
@@ -888,7 +893,7 @@ toLocalChatItem currentTs ((itemId, itemTs, AMsgDirection msgDir, itemContentTex
             _ -> Just (CIDeleted @'CTLocal deletedTs)
           itemEdited' = maybe False unBI itemEdited
           itemForwarded = toCIForwardedFrom forwardedFromRow
-       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) currentTs itemTs Nothing createdAt updatedAt
+       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) userMention currentTs itemTs Nothing createdAt updatedAt
     ciTimed :: Maybe CITimed
     ciTimed = timedTTL >>= \ttl -> Just CITimed {ttl, deleteAt = timedDeleteAt}
 
@@ -1021,6 +1026,7 @@ safeToDirectItem currentTs itemId = \case
               { chatDir = CIDirectSnd,
                 meta = dummyMeta itemId ts errorText,
                 content = CIInvalidJSON errorText,
+                mentions = M.empty,
                 formattedText = Nothing,
                 quotedItem = Nothing,
                 reactions = [],
@@ -1276,6 +1282,7 @@ safeToGroupItem currentTs itemId = \case
               { chatDir = CIGroupSnd,
                 meta = dummyMeta itemId ts errorText,
                 content = CIInvalidJSON errorText,
+                mentions = M.empty,
                 formattedText = Nothing,
                 quotedItem = Nothing,
                 reactions = [],
@@ -1501,6 +1508,7 @@ safeToLocalItem currentTs itemId = \case
               { chatDir = CILocalSnd,
                 meta = dummyMeta itemId ts errorText,
                 content = CIInvalidJSON errorText,
+                mentions = M.empty,
                 formattedText = Nothing,
                 quotedItem = Nothing,
                 reactions = [],
@@ -1810,7 +1818,7 @@ updateLocalChatItemsRead db User {userId} noteFolderId = do
 
 type MaybeCIFIleRow = (Maybe Int64, Maybe String, Maybe Integer, Maybe FilePath, Maybe C.SbKey, Maybe C.CbNonce, Maybe ACIFileStatus, Maybe FileProtocol)
 
-type ChatItemModeRow = (Maybe Int, Maybe UTCTime, Maybe BoolInt)
+type ChatItemModeRow = (Maybe Int, Maybe UTCTime, Maybe BoolInt, BoolInt)
 
 type ChatItemForwardedFromRow = (Maybe CIForwardedFromTag, Maybe Text, Maybe MsgDirection, Maybe Int64, Maybe Int64, Maybe Int64)
 
@@ -1834,7 +1842,7 @@ toQuote (quotedItemId, quotedSharedMsgId, quotedSentAt, quotedMsgContent, _) dir
 
 -- this function can be changed so it never fails, not only avoid failure on invalid json
 toDirectChatItem :: UTCTime -> ChatItemRow :. QuoteRow -> Either StoreError (CChatItem 'CTDirect)
-toDirectChatItem currentTs (((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) :. quoteRow) =
+toDirectChatItem currentTs (((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive, BI userMention) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) :. quoteRow) =
   chatItem $ fromRight invalid $ dbParseACIContent itemContentText
   where
     invalid = ACIContent msgDir $ CIInvalidJSON itemContentText
@@ -1858,7 +1866,7 @@ toDirectChatItem currentTs (((itemId, itemTs, AMsgDirection msgDir, itemContentT
         _ -> Nothing
     cItem :: MsgDirectionI d => SMsgDirection d -> CIDirection 'CTDirect d -> CIStatus d -> CIContent d -> Maybe (CIFile d) -> CChatItem 'CTDirect
     cItem d chatDir ciStatus content file =
-      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, formattedText = parseMaybeMarkdownList itemText, quotedItem = toDirectQuote quoteRow, reactions = [], file}
+      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, mentions = M.empty, formattedText = parseMaybeMarkdownList itemText, quotedItem = toDirectQuote quoteRow, reactions = [], file}
     badItem = Left $ SEBadChatItem itemId (Just itemTs)
     ciMeta :: CIContent d -> CIStatus d -> CIMeta 'CTDirect d
     ciMeta content status =
@@ -1867,7 +1875,7 @@ toDirectChatItem currentTs (((itemId, itemTs, AMsgDirection msgDir, itemContentT
             _ -> Just (CIDeleted @'CTDirect deletedTs)
           itemEdited' = maybe False unBI itemEdited
           itemForwarded = toCIForwardedFrom forwardedFromRow
-       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) currentTs itemTs Nothing createdAt updatedAt
+       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) userMention currentTs itemTs Nothing createdAt updatedAt
     ciTimed :: Maybe CITimed
     ciTimed = timedTTL >>= \ttl -> Just CITimed {ttl, deleteAt = timedDeleteAt}
 
@@ -1891,7 +1899,7 @@ toGroupQuote qr@(_, _, _, _, quotedSent) quotedMember_ = toQuote qr $ direction
 
 -- this function can be changed so it never fails, not only avoid failure on invalid json
 toGroupChatItem :: UTCTime -> Int64 -> ChatItemRow :. Only (Maybe GroupMemberId) :. MaybeGroupMemberRow :. GroupQuoteRow :. MaybeGroupMemberRow -> Either StoreError (CChatItem 'CTGroup)
-toGroupChatItem currentTs userContactId (((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) :. Only forwardedByMember :. memberRow_ :. (quoteRow :. quotedMemberRow_) :. deletedByGroupMemberRow_) = do
+toGroupChatItem currentTs userContactId (((itemId, itemTs, AMsgDirection msgDir, itemContentText, itemText, itemStatus, sentViaProxy, sharedMsgId) :. (itemDeleted, deletedTs, itemEdited, createdAt, updatedAt) :. forwardedFromRow :. (timedTTL, timedDeleteAt, itemLive, BI userMention) :. (fileId_, fileName_, fileSize_, filePath, fileKey, fileNonce, fileStatus_, fileProtocol_)) :. Only forwardedByMember :. memberRow_ :. (quoteRow :. quotedMemberRow_) :. deletedByGroupMemberRow_) = do
   chatItem $ fromRight invalid $ dbParseACIContent itemContentText
   where
     member_ = toMaybeGroupMember userContactId memberRow_
@@ -1918,7 +1926,7 @@ toGroupChatItem currentTs userContactId (((itemId, itemTs, AMsgDirection msgDir,
         _ -> Nothing
     cItem :: MsgDirectionI d => SMsgDirection d -> CIDirection 'CTGroup d -> CIStatus d -> CIContent d -> Maybe (CIFile d) -> CChatItem 'CTGroup
     cItem d chatDir ciStatus content file =
-      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, formattedText = parseMaybeMarkdownList itemText, quotedItem = toGroupQuote quoteRow quotedMember_, reactions = [], file}
+      CChatItem d ChatItem {chatDir, meta = ciMeta content ciStatus, content, mentions = M.empty, formattedText = parseMaybeMarkdownList itemText, quotedItem = toGroupQuote quoteRow quotedMember_, reactions = [], file}
     badItem = Left $ SEBadChatItem itemId (Just itemTs)
     ciMeta :: CIContent d -> CIStatus d -> CIMeta 'CTGroup d
     ciMeta content status =
@@ -1929,7 +1937,7 @@ toGroupChatItem currentTs userContactId (((itemId, itemTs, AMsgDirection msgDir,
             _ -> Just (maybe (CIDeleted @'CTGroup deletedTs) (CIModerated deletedTs) deletedByGroupMember_)
           itemEdited' = maybe False unBI itemEdited
           itemForwarded = toCIForwardedFrom forwardedFromRow
-       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) currentTs itemTs forwardedByMember createdAt updatedAt
+       in mkCIMeta itemId content itemText status (unBI <$> sentViaProxy) sharedMsgId itemForwarded itemDeleted' itemEdited' ciTimed (unBI <$> itemLive) userMention currentTs itemTs forwardedByMember createdAt updatedAt
     ciTimed :: Maybe CITimed
     ciTimed = timedTTL >>= \ttl -> Just CITimed {ttl, deleteAt = timedDeleteAt}
 
@@ -2202,7 +2210,7 @@ getDirectChatItem db User {userId} contactId itemId = ExceptT $ do
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol,
             -- DirectQuote
@@ -2254,12 +2262,14 @@ getGroupCIWithReactions db user g@GroupInfo {groupId} itemId = do
   liftIO . groupCIWithReactions db g =<< getGroupChatItem db user groupId itemId
 
 groupCIWithReactions :: DB.Connection -> GroupInfo -> CChatItem 'CTGroup -> IO (CChatItem 'CTGroup)
-groupCIWithReactions db g cci@(CChatItem md ci@ChatItem {meta = CIMeta {itemSharedMsgId}}) = case itemSharedMsgId of
-  Just sharedMsgId -> do
-    let GroupMember {memberId} = chatItemMember g ci
-    reactions <- getGroupCIReactions db g memberId sharedMsgId
-    pure $ CChatItem md ci {reactions}
-  Nothing -> pure cci
+groupCIWithReactions db g cci@(CChatItem md ci@ChatItem {meta = CIMeta {itemId, itemSharedMsgId}}) = do
+  mentions <- getGroupCIMentions db itemId
+  case itemSharedMsgId of
+    Just sharedMsgId -> do
+      let GroupMember {memberId} = chatItemMember g ci
+      reactions <- getGroupCIReactions db g memberId sharedMsgId
+      pure $ CChatItem md ci {reactions, mentions}
+    Nothing -> pure $ if null mentions then cci else CChatItem md ci {mentions}
 
 updateGroupChatItem :: MsgDirectionI d => DB.Connection -> User -> Int64 -> ChatItem 'CTGroup d -> CIContent d -> Bool -> Bool -> Maybe MessageId -> IO (ChatItem 'CTGroup d)
 updateGroupChatItem db user groupId ci newContent edited live msgId_ = do
@@ -2285,6 +2295,25 @@ updateGroupChatItem_ db User {userId} groupId ChatItem {content, meta} msgId_ =
     ((content, itemText, itemStatus, BI itemDeleted', itemDeletedTs', BI itemEdited, BI <$> itemLive, updatedAt) :. ciTimedRow itemTimed :. (userId, groupId, itemId))
   forM_ msgId_ $ \msgId -> insertChatItemMessage_ db itemId msgId updatedAt
 
+createGroupCIMentions :: forall d. DB.Connection -> GroupInfo -> ChatItem 'CTGroup d -> Map MemberName MentionedMember -> IO (ChatItem 'CTGroup d)
+createGroupCIMentions db GroupInfo {groupId} ci mentions = do
+  DB.executeMany db "INSERT INTO chat_item_mentions (chat_item_id, group_id, member_id, display_name) VALUES (?, ?, ?, ?)" rows
+  pure (ci :: ChatItem 'CTGroup d) {mentions}
+  where
+    rows = map (\(name, MentionedMember {memberId}) -> (ciId, groupId, memberId, name)) $ M.assocs mentions
+    ciId = chatItemId' ci
+
+updateGroupCIMentions :: DB.Connection -> GroupInfo -> ChatItem 'CTGroup d -> Map MemberName MentionedMember -> IO (ChatItem 'CTGroup d)
+updateGroupCIMentions db g ci@ChatItem {mentions} mentions'
+  | mentions' == mentions = pure ci
+  | otherwise = do
+      unless (null mentions) $ deleteMentions
+      if null mentions'
+        then pure ci
+        else createGroupCIMentions db g ci mentions'
+  where
+    deleteMentions = DB.execute db "DELETE FROM chat_item_mentions WHERE chat_item_id = ?" (Only $ chatItemId' ci)
+
 deleteGroupChatItem :: DB.Connection -> User -> GroupInfo -> ChatItem 'CTGroup d -> IO ()
 deleteGroupChatItem db User {userId} g@GroupInfo {groupId} ci = do
   let itemId = chatItemId' ci
@@ -2458,7 +2487,7 @@ getGroupChatItem db User {userId, userContactId} groupId itemId = ExceptT $ do
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol,
             -- CIMeta forwardedByMember
@@ -2562,7 +2591,7 @@ getLocalChatItem db User {userId} folderId itemId = ExceptT $ do
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol
           FROM chat_items i
@@ -2760,6 +2789,28 @@ getGroupCIReactions db GroupInfo {groupId} itemMemberId itemSharedMsgId =
       |]
       (groupId, itemMemberId, itemSharedMsgId)
 
+getGroupCIMentions :: DB.Connection -> ChatItemId -> IO (Map MemberName MentionedMember)
+getGroupCIMentions db ciId =
+  M.fromList . map mentionedMember
+    <$> DB.query
+      db
+      [sql|
+        SELECT r.display_name, r.member_id, m.group_member_id, m.member_role, p.display_name, p.local_alias
+        FROM chat_item_mentions r
+        LEFT JOIN group_members m ON r.group_id = m.group_id AND r.member_id = m.member_id
+        LEFT JOIN contact_profiles p ON p.contact_profile_id = COALESCE(m.member_profile_id, m.contact_profile_id) 
+        WHERE r.chat_item_id = ?
+      |]
+      (Only ciId)
+  where
+    mentionedMember :: (ContactName, MemberId, Maybe GroupMemberId, Maybe GroupMemberRole, Maybe Text, Maybe Text) -> (ContactName, MentionedMember)
+    mentionedMember (name, memberId, gmId_, mRole_, displayName_, localAlias) =
+      let memberRef = case (gmId_, mRole_, displayName_) of
+            (Just groupMemberId, Just memberRole, Just displayName) ->
+              Just MentionedMemberInfo {groupMemberId, displayName, localAlias, memberRole}
+            _ -> Nothing
+       in (name, MentionedMember {memberId, memberRef})
+
 getACIReactions :: DB.Connection -> AChatItem -> IO AChatItem
 getACIReactions db aci@(AChatItem _ md chat ci@ChatItem {meta = CIMeta {itemSharedMsgId}}) = case itemSharedMsgId of
   Just itemSharedMId -> case chat of

src/Simplex/Chat/Store/Postgres/Migrations/M20241220_initial.hs

@@ -426,7 +426,8 @@ CREATE TABLE chat_items(
   fwd_from_chat_item_id BIGINT REFERENCES chat_items ON DELETE SET NULL,
   via_proxy SMALLINT,
   msg_content_tag TEXT,
-  include_in_history SMALLINT NOT NULL DEFAULT 0
+  include_in_history SMALLINT NOT NULL DEFAULT 0,
+  user_mention SMALLINT NOT NULL DEFAULT 0
 );
 ALTER TABLE groups
 ADD CONSTRAINT fk_groups_chat_items
@@ -676,6 +677,13 @@ CREATE TABLE chat_tags_chats(
   group_id BIGINT REFERENCES groups ON DELETE CASCADE,
   chat_tag_id BIGINT NOT NULL REFERENCES chat_tags ON DELETE CASCADE
 );
+CREATE TABLE chat_item_mentions (
+  chat_item_mention_id BIGINT PRIMARY KEY GENERATED ALWAYS AS IDENTITY,
+  chat_item_id BIGINT NOT NULL REFERENCES chat_items ON DELETE CASCADE,
+  group_id BIGINT NOT NULL REFERENCES groups ON DELETE CASCADE,
+  member_id BYTEA NOT NULL,
+  display_name TEXT NOT NULL
+);
 CREATE INDEX contact_profiles_index ON contact_profiles(
   display_name,
   full_name
@@ -1025,4 +1033,8 @@ CREATE INDEX idx_group_snd_item_statuses_chat_item_id_group_member_id ON group_s
   chat_item_id,
   group_member_id
 );
+CREATE INDEX idx_chat_item_mentions_group_id ON chat_item_mentions(group_id);
+CREATE INDEX idx_chat_item_mentions_chat_item_id ON chat_item_mentions(chat_item_id);
+CREATE UNIQUE INDEX idx_chat_item_mentions_display_name ON chat_item_mentions(chat_item_id, display_name);
+CREATE UNIQUE INDEX idx_chat_item_mentions_member_id ON chat_item_mentions(chat_item_id, member_id);
 |]

src/Simplex/Chat/Store/SQLite/Migrations.hs

@@ -125,6 +125,7 @@ import Simplex.Chat.Store.SQLite.Migrations.M20241230_reports
 import Simplex.Chat.Store.SQLite.Migrations.M20250105_indexes
 import Simplex.Chat.Store.SQLite.Migrations.M20250115_chat_ttl
 import Simplex.Chat.Store.SQLite.Migrations.M20250122_chat_items_include_in_history
+import Simplex.Chat.Store.SQLite.Migrations.M20250126_mentions
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Query, Maybe Query)]
@@ -249,7 +250,8 @@ schemaMigrations =
     ("20241230_reports", m20241230_reports, Just down_m20241230_reports),
     ("20250105_indexes", m20250105_indexes, Just down_m20250105_indexes),
     ("20250115_chat_ttl", m20250115_chat_ttl, Just down_m20250115_chat_ttl),
-    ("20250122_chat_items_include_in_history", m20250122_chat_items_include_in_history, Just down_m20250122_chat_items_include_in_history)
+    ("20250122_chat_items_include_in_history", m20250122_chat_items_include_in_history, Just down_m20250122_chat_items_include_in_history),
+    ("20250126_mentions", m20250126_mentions, Just down_m20250126_mentions)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/SQLite/Migrations/M20250126_mentions.hs

@@ -0,0 +1,37 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.SQLite.Migrations.M20250126_mentions where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20250126_mentions :: Query
+m20250126_mentions =
+  [sql|
+ALTER TABLE chat_items ADD COLUMN user_mention INTEGER NOT NULL DEFAULT 0;
+
+CREATE TABLE chat_item_mentions (
+  chat_item_mention_id INTEGER PRIMARY KEY AUTOINCREMENT,
+  group_id INTEGER NOT NULL REFERENCES groups ON DELETE CASCADE,
+  member_id BLOB NOT NULL,
+  chat_item_id INTEGER NOT NULL REFERENCES chat_items ON DELETE CASCADE,
+  display_name TEXT NOT NULL
+);
+
+CREATE INDEX idx_chat_item_mentions_group_id ON chat_item_mentions(group_id);
+CREATE INDEX idx_chat_item_mentions_chat_item_id ON chat_item_mentions(chat_item_id);
+CREATE UNIQUE INDEX idx_chat_item_mentions_display_name ON chat_item_mentions(chat_item_id, display_name);
+CREATE UNIQUE INDEX idx_chat_item_mentions_member_id ON chat_item_mentions(chat_item_id, member_id);
+|]
+
+down_m20250126_mentions :: Query
+down_m20250126_mentions =
+  [sql|
+DROP INDEX idx_chat_item_mentions_group_id;
+DROP INDEX idx_chat_item_mentions_chat_item_id;
+DROP INDEX idx_chat_item_mentions_display_name;
+DROP INDEX idx_chat_item_mentions_member_id;
+
+DROP TABLE chat_item_mentions;
+ALTER TABLE chat_items DROP COLUMN user_mention;
+|]

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

@@ -714,7 +714,7 @@ Query:
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol
           FROM chat_items i
@@ -731,7 +731,7 @@ Query:
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol,
             -- CIMeta forwardedByMember
@@ -778,7 +778,7 @@ Query:
             i.chat_item_id, i.item_ts, i.item_sent, i.item_content, i.item_text, i.item_status, i.via_proxy, i.shared_msg_id,
             i.item_deleted, i.item_deleted_ts, i.item_edited, i.created_at, i.updated_at,
             i.fwd_from_tag, i.fwd_from_chat_name, i.fwd_from_msg_dir, i.fwd_from_contact_id, i.fwd_from_group_id, i.fwd_from_chat_item_id,
-            i.timed_ttl, i.timed_delete_at, i.item_live,
+            i.timed_ttl, i.timed_delete_at, i.item_live, i.user_mention,
             -- CIFile
             f.file_id, f.file_name, f.file_size, f.file_path, f.file_crypto_key, f.file_crypto_nonce, f.ci_file_status, f.protocol,
             -- DirectQuote
@@ -3295,6 +3295,18 @@ SEARCH r USING INDEX idx_received_probes_user_id (user_id=?)
 SEARCH m USING INTEGER PRIMARY KEY (rowid=?) LEFT-JOIN
 SEARCH g USING INTEGER PRIMARY KEY (rowid=?) LEFT-JOIN
 
+Query: 
+        SELECT r.display_name, r.member_id, m.group_member_id, m.member_role, p.display_name, p.local_alias
+        FROM chat_item_mentions r
+        LEFT JOIN group_members m ON r.group_id = m.group_id AND r.member_id = m.member_id
+        LEFT JOIN contact_profiles p ON p.contact_profile_id = COALESCE(m.member_profile_id, m.contact_profile_id) 
+        WHERE r.chat_item_id = ?
+      
+Plan:
+SEARCH r USING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
+SEARCH m USING INDEX sqlite_autoindex_group_members_1 (group_id=? AND member_id=?) LEFT-JOIN
+SEARCH p USING INTEGER PRIMARY KEY (rowid=?) LEFT-JOIN
+
 Query: 
         SELECT re_group_member_id
         FROM group_member_intros
@@ -3489,6 +3501,7 @@ Query:
     
 Plan:
 SEARCH chat_items USING INTEGER PRIMARY KEY (rowid=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -3503,6 +3516,7 @@ Query:
     
 Plan:
 SEARCH chat_items USING INTEGER PRIMARY KEY (rowid=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -3517,6 +3531,7 @@ Query:
     
 Plan:
 SEARCH chat_items USING INTEGER PRIMARY KEY (rowid=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -3964,12 +3979,12 @@ Query:
         user_id, created_by_msg_id, contact_id, group_id, group_member_id, note_folder_id,
         -- meta
         item_sent, item_ts, item_content, item_content_tag, item_text, item_status, msg_content_tag, shared_msg_id,
-        forwarded_by_group_member_id, include_in_history, created_at, updated_at, item_live, timed_ttl, timed_delete_at,
+        forwarded_by_group_member_id, include_in_history, created_at, updated_at, item_live, user_mention, timed_ttl, timed_delete_at,
         -- quote
         quoted_shared_msg_id, quoted_sent_at, quoted_content, quoted_sent, quoted_member_id,
         -- forwarded from
         fwd_from_tag, fwd_from_chat_name, fwd_from_msg_dir, fwd_from_contact_id, fwd_from_group_id, fwd_from_chat_item_id
-      ) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
+      ) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
     
 Plan:
 
@@ -4690,6 +4705,24 @@ Plan:
 SEARCH i USING COVERING INDEX idx_chat_items_notes_created_at (user_id=? AND note_folder_id=?)
 SEARCH f USING INDEX idx_files_chat_item_id (chat_item_id=?)
 
+Query: 
+    SELECT m.group_member_id, m.member_id, m.member_role, p.display_name, p.local_alias
+    FROM group_members m
+    JOIN contact_profiles p ON p.contact_profile_id = COALESCE(m.member_profile_id, m.contact_profile_id)
+   WHERE m.group_id = ? AND m.group_member_id = ? AND m.user_id = ?
+Plan:
+SEARCH m USING INTEGER PRIMARY KEY (rowid=?)
+SEARCH p USING INTEGER PRIMARY KEY (rowid=?)
+
+Query: 
+    SELECT m.group_member_id, m.member_id, m.member_role, p.display_name, p.local_alias
+    FROM group_members m
+    JOIN contact_profiles p ON p.contact_profile_id = COALESCE(m.member_profile_id, m.contact_profile_id)
+   WHERE m.group_id = ? AND m.member_id = ? AND m.user_id = ?
+Plan:
+SEARCH m USING INDEX sqlite_autoindex_group_members_1 (group_id=? AND member_id=?)
+SEARCH p USING INTEGER PRIMARY KEY (rowid=?)
+
 Query: 
     SELECT remote_ctrl_id, ctrl_device_name, ca_key, ca_cert, ctrl_fingerprint, id_pub, dh_priv_key, prev_dh_priv_key
     FROM remote_controllers
@@ -4957,6 +4990,7 @@ SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_
 Query: DELETE FROM chat_items WHERE user_id = ? AND contact_id = ?
 Plan:
 SEARCH chat_items USING COVERING INDEX idx_chat_items_contacts_created_at (user_id=? AND contact_id=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -4968,6 +5002,7 @@ SEARCH groups USING COVERING INDEX idx_groups_chat_item_id (chat_item_id=?)
 Query: DELETE FROM chat_items WHERE user_id = ? AND contact_id = ? AND created_at <= ?
 Plan:
 SEARCH chat_items USING COVERING INDEX idx_chat_items_contacts_created_at (user_id=? AND contact_id=? AND created_at<?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -4979,6 +5014,7 @@ SEARCH groups USING COVERING INDEX idx_groups_chat_item_id (chat_item_id=?)
 Query: DELETE FROM chat_items WHERE user_id = ? AND group_id = ?
 Plan:
 SEARCH chat_items USING COVERING INDEX idx_chat_items_groups_item_ts (user_id=? AND group_id=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -4990,6 +5026,7 @@ SEARCH groups USING COVERING INDEX idx_groups_chat_item_id (chat_item_id=?)
 Query: DELETE FROM chat_items WHERE user_id = ? AND group_id = ? AND group_member_id = ?
 Plan:
 SEARCH chat_items USING COVERING INDEX idx_chat_items_group_shared_msg_id (user_id=? AND group_id=? AND group_member_id=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -5001,6 +5038,7 @@ SEARCH groups USING COVERING INDEX idx_groups_chat_item_id (chat_item_id=?)
 Query: DELETE FROM chat_items WHERE user_id = ? AND note_folder_id = ?
 Plan:
 SEARCH chat_items USING COVERING INDEX idx_chat_items_notes_created_at (user_id=? AND note_folder_id=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_chat_item_id (chat_item_id=?)
 SEARCH group_snd_item_statuses USING COVERING INDEX idx_group_snd_item_statuses_chat_item_id (chat_item_id=?)
 SEARCH chat_item_versions USING COVERING INDEX idx_chat_item_versions_chat_item_id (chat_item_id=?)
 SEARCH calls USING COVERING INDEX idx_calls_chat_item_id (chat_item_id=?)
@@ -5155,6 +5193,7 @@ SEARCH contacts USING COVERING INDEX idx_contacts_contact_group_member_id (conta
 Query: DELETE FROM groups WHERE user_id = ? AND group_id = ?
 Plan:
 SEARCH groups USING INTEGER PRIMARY KEY (rowid=?)
+SEARCH chat_item_mentions USING COVERING INDEX idx_chat_item_mentions_group_id (group_id=?)
 SEARCH chat_tags_chats USING COVERING INDEX idx_chat_tags_chats_chat_tag_id_group_id (group_id=?)
 SEARCH chat_item_moderations USING COVERING INDEX idx_chat_item_moderations_group_id (group_id=?)
 SEARCH chat_item_reactions USING COVERING INDEX idx_chat_item_reactions_group_id (group_id=?)
@@ -5293,6 +5332,9 @@ Plan:
 Query: INSERT INTO app_settings (app_settings) VALUES (?)
 Plan:
 
+Query: INSERT INTO chat_item_mentions (chat_item_id, group_id, member_id, display_name) VALUES (?, ?, ?, ?)
+Plan:
+
 Query: INSERT INTO chat_item_messages (chat_item_id, message_id, created_at, updated_at) VALUES (?,?,?,?)
 Plan:
 

src/Simplex/Chat/Store/SQLite/Migrations/chat_schema.sql

@@ -407,7 +407,8 @@ CREATE TABLE chat_items(
   fwd_from_chat_item_id INTEGER REFERENCES chat_items ON DELETE SET NULL,
   via_proxy INTEGER,
   msg_content_tag TEXT,
-  include_in_history INTEGER NOT NULL DEFAULT 0
+  include_in_history INTEGER NOT NULL DEFAULT 0,
+  user_mention INTEGER NOT NULL DEFAULT 0
 );
 CREATE TABLE sqlite_sequence(name,seq);
 CREATE TABLE chat_item_messages(
@@ -642,6 +643,13 @@ CREATE TABLE chat_tags_chats(
   group_id INTEGER REFERENCES groups ON DELETE CASCADE,
   chat_tag_id INTEGER NOT NULL REFERENCES chat_tags ON DELETE CASCADE
 );
+CREATE TABLE chat_item_mentions(
+  chat_item_mention_id INTEGER PRIMARY KEY AUTOINCREMENT,
+  group_id INTEGER NOT NULL REFERENCES groups ON DELETE CASCADE,
+  member_id BLOB NOT NULL,
+  chat_item_id INTEGER NOT NULL REFERENCES chat_items ON DELETE CASCADE,
+  display_name TEXT NOT NULL
+);
 CREATE INDEX contact_profiles_index ON contact_profiles(
   display_name,
   full_name
@@ -991,3 +999,15 @@ CREATE INDEX idx_group_snd_item_statuses_chat_item_id_group_member_id ON group_s
   chat_item_id,
   group_member_id
 );
+CREATE INDEX idx_chat_item_mentions_group_id ON chat_item_mentions(group_id);
+CREATE INDEX idx_chat_item_mentions_chat_item_id ON chat_item_mentions(
+  chat_item_id
+);
+CREATE UNIQUE INDEX idx_chat_item_mentions_display_name ON chat_item_mentions(
+  chat_item_id,
+  display_name
+);
+CREATE UNIQUE INDEX idx_chat_item_mentions_member_id ON chat_item_mentions(
+  chat_item_id,
+  member_id
+);

src/Simplex/Chat/Store/Shared.hs

@@ -140,6 +140,8 @@ data StoreError
   | SEProhibitedDeleteUser {userId :: UserId, contactId :: ContactId}
   | SEOperatorNotFound {serverOperatorId :: Int64}
   | SEUsageConditionsNotFound
+  | SEInvalidQuote
+  | SEInvalidMention
   deriving (Show, Exception)
 
 $(J.deriveJSON (sumTypeJSON $ dropPrefix "SE") ''StoreError)