discuss & clean up message pull

[tomholub]

@DenBond7 The problem is that Node only receives the first 200kb message. That works for some messages, but not for all. Especially pgp/mime messages that are a bit longer (eg contain an attachment) will not work.

I think we should stop using the 200kb method, and just download the whole message every time. For that, it would be good to have a % indication on the bottom, similar to loading inbox.

Originally posted by @tomholub in #518 (comment)

[tomholub]

Doesn't make sense to always pull whole message, what if it's 20mb?

For now a compromise could be to show a message:

This message is 18.5 MB large. Download and display anyway?

[tomholub]

Now it's 1MB

[DenBond7]

What kind of BODYSTRUCTURE can we have? Why am I asking?
Maybe we can analyze first 10kb-100kb of the raw MIME message and check does it contain "-----BEGIN PGP MESSAGE-----". If yes we will download the whole message.

But this method will not work if a message will have an attachment in the begin.
But for GMAIL we can use the search request which can look like
rfc822msgid:200503292@example.com "-----BEGIN PGP MESSAGE-----", where 200503292@example.com - it's a Message-Id header.

For other providers, we can use the following command (Standard IMAP SEARCH)
A11 UID SEARCH HEADER Message-ID <200503292@example.com> TEXT "-----BEGIN PGP MESSAGE-----"

@tomholub What do you think?

[tomholub]

It's more complicated than that. There are about 10 different ways to find out if a message is pgp.

• attachments of various different names
• sometimes also based on their content
• various headers
• presence of "-----BEGIN PGP MESSAGE-----" or "-----BEGIN PGP SIGNED MESSAGE-----" or even "-----BEGIN PGP PUBLIC KEY-----" etc.

The most reliable way is to give the whole thing to parseDecryptMsg and let it figure it out.

I would look into this in another version.

One idea is to add a button in three dots -> Decrypt message, that only shows if we detect it as a normal message. On the other hand, if we detected it as encrypted, it should say Show without decrypting. That way if our detection fails, user can still switch.