Change folders() signature:
- fn folders(&self) -> FnvHashMap<FolderHash, Folder>;
+ fn folders(&self) -> Result<FnvHashMap<FolderHash, Folder>>;
Imap may not be online, therefore we need the ability to return an
error.
fetch BODYSTRUCTURE along with ENVELOPE from server and set
has_attachments based on the MIME structure of the envelope.
Notes: BODYSTRUCTURE returns the MIME structure of the envelope without
the data, so if it includes a multipart/mixed it *should* have
attachments.
ENVELOPE returns basic headers of the message like Sender, Subject, Date
etc.
Make startup methods return Results so that the main binary can exit
cleanly instead of using std::process::exit from arbitrary positions,
which exits the process immediately and doesn't run destructors.
The operation() method on the MailBackend trait returns a trait object
that can read or modify an Envelope directly from the backend. This is
used to get eg the envelope's text, or set flags. It has two arguments,
envelope hash and folder hash.
Only the Maildir backend needed the latter argument, and it can be replaced with a dictionary to match envelope hashes to folder hashes within the Maildir backend.
Add a boolean field to accounts that states if the account can be
accessed. Local backends (Maildir/mbox) return true every time, but
remote backends (IMAP) may not. Accounts start as offline and then get
initialised when their status goes to online. Right now if an IMAP
account startup but later get offline, there are crashes. With this
change the account can be switched back to offline when that happens.
Split the TlsStream of the live IMAP connection to an enum to allow both
offline and online states. The connection is restarted if offline when
requested.