Added get_url() method for Message object and shifted_id property for Chat object

aiogram/types/chat.py

@@ -54,3 +54,11 @@ class Chat(TelegramObject):
     """*Optional*. Unique identifier for the linked chat, i.e. the discussion group identifier for a channel and vice versa; for supergroups and channel chats. This identifier may be greater than 32 bits and some programming languages may have difficulty/silent defects in interpreting it. But it is smaller than 52 bits, so a signed 64 bit integer or double-precision float type are safe for storing this identifier. Returned only in :class:`aiogram.methods.get_chat.GetChat`."""
     location: Optional[ChatLocation] = None
     """*Optional*. For supergroups, the location to which the supergroup is connected. Returned only in :class:`aiogram.methods.get_chat.GetChat`."""
+
+    @property
+    def shifted_id(self) -> int:
+        """
+        Returns shifted chat ID (positive and without "-100" prefix.
+        Mostly used for private links like t.me/c/chat_id/message_id
+        """
+        return abs(self.id + 1_000_000_000_000)

aiogram/types/message.py

@@ -1714,6 +1714,26 @@ class Message(TelegramObject):
             reply_markup=reply_markup,
         )
 
+    def get_url(self, force_private: bool = False) -> str:
+        """
+        Returns message URL. Cannot be used in private (one-to-one) chats.
+        If chat has a username, returns URL like https://t.me/username/message_id
+        Otherwise (or if {force_private} flag is set), returns https://t.me/c/shifted_chat_id/message_id
+
+        :param force_private: if set, a private URL is returned even for a public chat
+        :return: string with full message URL
+        """
+        if self.chat.type == "private":
+            raise TypeError("Invalid chat type!")
+
+        url = "https://t.me/"
+        if not self.chat.username or force_private:
+            url += f"c/{self.chat.shifted_id}/"
+        else:
+            url += f"{self.chat.username}/"
+        url += f"{self.message_id}"
+        return url
+
 
 class ContentType(helper.Helper):
     mode = helper.HelperMode.snake_case