telegram: add group chat support

- Only respond in groups when @mentioned or replied to
- Add ChatType to TelegramMessage (private/group/supergroup/channel)
- Add getMe API call to fetch bot username on startup
- Add shouldRespondInGroup helper function

1 files changed, 47 insertions, 0 deletions

diff --git a/Omni/Agent/Telegram/Types.hs b/Omni/Agent/Telegram/Types.hs
index 2db6a52..d240786 100644
--- a/Omni/Agent/Telegram/Types.hs
+++ b/Omni/Agent/Telegram/Types.hs
@@ -19,6 +19,7 @@ module Omni.Agent.Telegram.Types
     TelegramPhoto (..),
     TelegramVoice (..),
     TelegramReplyMessage (..),
+    ChatType (..),
 
     -- * Parsing
     parseUpdate,
@@ -31,6 +32,8 @@ module Omni.Agent.Telegram.Types
     -- * Utilities
     isPdf,
     isSupportedVoiceFormat,
+    isGroupChat,
+    shouldRespondInGroup,
 
     -- * Testing
     main,
@@ -81,6 +84,7 @@ test =
               TelegramMessage
                 { tmUpdateId = 123,
                   tmChatId = 456,
+                  tmChatType = Private,
                   tmUserId = 789,
                   tmUserFirstName = "Test",
                   tmUserLastName = Just "User",
@@ -319,9 +323,28 @@ instance Aeson.FromJSON TelegramReplyMessage where
         <*> (v .:? "from_last_name")
         <*> (v .:? "text" .!= "")
 
+data ChatType = Private | Group | Supergroup | Channel
+  deriving (Show, Eq, Generic)
+
+instance Aeson.ToJSON ChatType where
+  toJSON Private = Aeson.String "private"
+  toJSON Group = Aeson.String "group"
+  toJSON Supergroup = Aeson.String "supergroup"
+  toJSON Channel = Aeson.String "channel"
+
+instance Aeson.FromJSON ChatType where
+  parseJSON = Aeson.withText "ChatType" parseChatType
+    where
+      parseChatType "private" = pure Private
+      parseChatType "group" = pure Group
+      parseChatType "supergroup" = pure Supergroup
+      parseChatType "channel" = pure Channel
+      parseChatType _ = pure Private
+
 data TelegramMessage = TelegramMessage
   { tmUpdateId :: Int,
     tmChatId :: Int,
+    tmChatType :: ChatType,
     tmUserId :: Int,
     tmUserFirstName :: Text,
     tmUserLastName :: Maybe Text,
@@ -338,6 +361,7 @@ instance Aeson.ToJSON TelegramMessage where
     Aeson.object
       [ "update_id" .= tmUpdateId m,
         "chat_id" .= tmChatId m,
+        "chat_type" .= tmChatType m,
         "user_id" .= tmUserId m,
         "user_first_name" .= tmUserFirstName m,
         "user_last_name" .= tmUserLastName m,
@@ -353,6 +377,7 @@ instance Aeson.FromJSON TelegramMessage where
     Aeson.withObject "TelegramMessage" <| \v ->
       (TelegramMessage </ (v .: "update_id"))
         <*> (v .: "chat_id")
+        <*> (v .:? "chat_type" .!= Private)
         <*> (v .: "user_id")
         <*> (v .: "user_first_name")
         <*> (v .:? "user_last_name")
@@ -385,6 +410,12 @@ parseUpdate val = do
   chatId <- case KeyMap.lookup "id" chatObj of
     Just (Aeson.Number n) -> Just (round n)
     _ -> Nothing
+  let chatType = case KeyMap.lookup "type" chatObj of
+        Just (Aeson.String "private") -> Private
+        Just (Aeson.String "group") -> Group
+        Just (Aeson.String "supergroup") -> Supergroup
+        Just (Aeson.String "channel") -> Channel
+        _ -> Private
   Aeson.Object fromObj <- KeyMap.lookup "from" msgObj
   userId <- case KeyMap.lookup "id" fromObj of
     Just (Aeson.Number n) -> Just (round n)
@@ -419,6 +450,7 @@ parseUpdate val = do
     TelegramMessage
       { tmUpdateId = updateId,
         tmChatId = chatId,
+        tmChatType = chatType,
         tmUserId = userId,
         tmUserFirstName = firstName,
         tmUserLastName = lastName,
@@ -547,3 +579,18 @@ isSupportedVoiceFormat voice =
     Just "audio/x-opus+ogg" -> True
     Nothing -> True
     _ -> False
+
+isGroupChat :: TelegramMessage -> Bool
+isGroupChat msg = tmChatType msg `elem` [Group, Supergroup]
+
+shouldRespondInGroup :: Text -> TelegramMessage -> Bool
+shouldRespondInGroup botUsername msg
+  | not (isGroupChat msg) = True
+  | isMentioned = True
+  | isReplyToBot = True
+  | otherwise = False
+  where
+    msgText = Text.toLower (tmText msg)
+    mention = "@" <> Text.toLower botUsername
+    isMentioned = mention `Text.isInfixOf` msgText
+    isReplyToBot = isJust (tmReplyTo msg)