Support passing user ids to commands that accept @usernames

telegram/utils.go

@@ -35,15 +35,27 @@ func (c *Client) GetContactByUsername(username string) (*client.Chat, *client.Us
 		return nil, nil, errOffline
 	}
 
-	chat, err := c.client.SearchPublicChat(&client.SearchPublicChatRequest{
-		Username: username,
-	})
+	var chat *client.Chat
+	var err error
+	var userID int64
+	if strings.HasPrefix(username, "@") {
+		chat, err = c.client.SearchPublicChat(&client.SearchPublicChatRequest{
+			Username: username,
+		})
 
-	if err != nil {
-		return nil, nil, err
+		if err != nil {
+			return nil, nil, err
+		}
+
+		userID = chat.Id
+	} else {
+		userID, err = strconv.ParseInt(username, 10, 64)
+		if err != nil {
+			return nil, nil, err
+		}
 	}
 
-	return c.GetContactByID(chat.Id, chat)
+	return c.GetContactByID(userID, chat)
 }
 
 // GetContactByID gets user and chat information from cache (or tries to retrieve it, if missing)