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use crate::mailbox::Mailbox;
pub struct User {
pub name: String,
pub creds: Credentials,
}
pub enum State {
NotAuthenticated,
Authenticated(User),
Selected(User, Mailbox),
Logout
}
pub enum Error {
ForbiddenTransition,
}
// See RFC3501 section 3.
// https://datatracker.ietf.org/doc/html/rfc3501#page-13
impl State {
pub fn authenticate(&mut self, user: User) -> Result<(), Error> {
self = match state {
State::NotAuthenticated => State::Authenticated(user),
_ => return Err(ForbiddenTransition),
};
Ok(())
}
pub fn logout(&mut self) -> Self {
self = State::Logout;
Ok(())
}
pub fn select(&mut self, mailbox: Mailbox) -> Result<(), Error> {
self = match state {
State::Authenticated(user) => State::Selected(user, mailbox),
_ => return Err(ForbiddenTransition),
};
Ok(())
}
pub fn unselect(state: State) -> Result<(), Error> {
self = match state {
State::Selected(user, _) => State::Authenticated(user),
_ => return Err(ForbiddenTransition),
};
Ok(())
}
}
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