[Feature] Import messages from other chat apps

[HighPriest]

Trying to use the "Import from Whatsapp" functionality, I am running into a wall with media files not being imported.
Apparently, the original Telegram, checks for the source of the incoming file and based on this, decides what extra parsing to do on the file (depending on if it is an import from WhatsApp or KakakoChat).
Here is some extra information on this topic:

• https://old.reddit.com/r/Telegram/comments/l8eyga/get_complete_text_chat_from_whatsapp_to_telegram/

Relevant lines in original telegram code:

• Parsing the file that was intended / shared, to determine, what to do with it
• Running the import request
• Import request method

EDIT:
I've found out, that Telegram had introduced a fully featured import API in the MTProto scheme. https://core.telegram.org/api/import
The API has been introduced just a little while after TLImporter application had been finalised, missing out on an easy way to handle this functionality.
With very little code, example export files & AI help, it should be possible to add robust chat history migration feature.