Merge branch 'caldav'

1 files changed, 175 insertions, 0 deletions

diff --git a/aero-proto/src/imap/session.rs b/aero-proto/src/imap/session.rs
new file mode 100644
index 0000000..92b5eb6
--- /dev/null
+++ b/aero-proto/src/imap/session.rs
@@ -0,0 +1,175 @@
+use anyhow::{anyhow, bail, Context, Result};
+use imap_codec::imap_types::{command::Command, core::Tag};
+
+use aero_user::login::ArcLoginProvider;
+
+use crate::imap::capability::{ClientCapability, ServerCapability};
+use crate::imap::command::{anonymous, authenticated, selected};
+use crate::imap::flow;
+use crate::imap::request::Request;
+use crate::imap::response::{Response, ResponseOrIdle};
+
+//-----
+pub struct Instance {
+    pub login_provider: ArcLoginProvider,
+    pub server_capabilities: ServerCapability,
+    pub client_capabilities: ClientCapability,
+    pub state: flow::State,
+}
+impl Instance {
+    pub fn new(login_provider: ArcLoginProvider, cap: ServerCapability) -> Self {
+        let client_cap = ClientCapability::new(&cap);
+        Self {
+            login_provider,
+            state: flow::State::NotAuthenticated,
+            server_capabilities: cap,
+            client_capabilities: client_cap,
+        }
+    }
+
+    pub async fn request(&mut self, req: Request) -> ResponseOrIdle {
+        match req {
+            Request::IdleStart(tag) => self.idle_init(tag),
+            Request::IdlePoll => self.idle_poll().await,
+            Request::ImapCommand(cmd) => self.command(cmd).await,
+        }
+    }
+
+    pub fn idle_init(&mut self, tag: Tag<'static>) -> ResponseOrIdle {
+        // Build transition
+        //@FIXME the notifier should be hidden inside the state and thus not part of the transition!
+        let transition = flow::Transition::Idle(tag.clone(), tokio::sync::Notify::new());
+
+        // Try to apply the transition and get the stop notifier
+        let maybe_stop = self
+            .state
+            .apply(transition)
+            .context("IDLE transition failed")
+            .and_then(|_| {
+                self.state
+                    .notify()
+                    .ok_or(anyhow!("IDLE state has no Notify object"))
+            });
+
+        // Build an appropriate response
+        match maybe_stop {
+            Ok(stop) => ResponseOrIdle::IdleAccept(stop),
+            Err(e) => {
+                tracing::error!(err=?e, "unable to init idle due to a transition error");
+                //ResponseOrIdle::IdleReject(tag)
+                let no = Response::build()
+                    .tag(tag)
+                    .message(
+                        "Internal error, processing command triggered an illegal IMAP state transition",
+                    )
+                    .no()
+                    .unwrap();
+                ResponseOrIdle::IdleReject(no)
+            }
+        }
+    }
+
+    pub async fn idle_poll(&mut self) -> ResponseOrIdle {
+        match self.idle_poll_happy().await {
+            Ok(r) => r,
+            Err(e) => {
+                tracing::error!(err=?e, "something bad happened in idle");
+                ResponseOrIdle::Response(Response::bye().unwrap())
+            }
+        }
+    }
+
+    pub async fn idle_poll_happy(&mut self) -> Result<ResponseOrIdle> {
+        let (mbx, tag, stop) = match &mut self.state {
+            flow::State::Idle(_, ref mut mbx, _, tag, stop) => (mbx, tag.clone(), stop.clone()),
+            _ => bail!("Invalid session state, can't idle"),
+        };
+
+        tokio::select! {
+            _ = stop.notified() => {
+                self.state.apply(flow::Transition::UnIdle)?;
+                return Ok(ResponseOrIdle::Response(Response::build()
+                    .tag(tag.clone())
+                    .message("IDLE completed")
+                    .ok()?))
+            },
+            change = mbx.idle_sync() => {
+                tracing::debug!("idle event");
+                return Ok(ResponseOrIdle::IdleEvent(change?));
+            }
+        }
+    }
+
+    pub async fn command(&mut self, cmd: Command<'static>) -> ResponseOrIdle {
+        // Command behavior is modulated by the state.
+        // To prevent state error, we handle the same command in separate code paths.
+        let (resp, tr) = match &mut self.state {
+            flow::State::NotAuthenticated => {
+                let ctx = anonymous::AnonymousContext {
+                    req: &cmd,
+                    login_provider: &self.login_provider,
+                    server_capabilities: &self.server_capabilities,
+                };
+                anonymous::dispatch(ctx).await
+            }
+            flow::State::Authenticated(ref user) => {
+                let ctx = authenticated::AuthenticatedContext {
+                    req: &cmd,
+                    server_capabilities: &self.server_capabilities,
+                    client_capabilities: &mut self.client_capabilities,
+                    user,
+                };
+                authenticated::dispatch(ctx).await
+            }
+            flow::State::Selected(ref user, ref mut mailbox, ref perm) => {
+                let ctx = selected::SelectedContext {
+                    req: &cmd,
+                    server_capabilities: &self.server_capabilities,
+                    client_capabilities: &mut self.client_capabilities,
+                    user,
+                    mailbox,
+                    perm,
+                };
+                selected::dispatch(ctx).await
+            }
+            flow::State::Idle(..) => Err(anyhow!("can not receive command while idling")),
+            flow::State::Logout => Response::build()
+                .tag(cmd.tag.clone())
+                .message("No commands are allowed in the LOGOUT state.")
+                .bad()
+                .map(|r| (r, flow::Transition::None)),
+        }
+        .unwrap_or_else(|err| {
+            tracing::error!("Command error {:?} occured while processing {:?}", err, cmd);
+            (
+                Response::build()
+                    .to_req(&cmd)
+                    .message("Internal error while processing command")
+                    .bad()
+                    .unwrap(),
+                flow::Transition::None,
+            )
+        });
+
+        if let Err(e) = self.state.apply(tr) {
+            tracing::error!(
+                "Transition error {:?} occured while processing on command {:?}",
+                e,
+                cmd
+            );
+            return ResponseOrIdle::Response(Response::build()
+                .to_req(&cmd)
+                .message(
+                    "Internal error, processing command triggered an illegal IMAP state transition",
+                )
+                .bad()
+                .unwrap());
+        }
+        ResponseOrIdle::Response(resp)
+
+        /*match &self.state {
+            flow::State::Idle(_, _, _, _, n) => ResponseOrIdle::StartIdle(n.clone()),
+            _ => ResponseOrIdle::Response(resp),
+        }*/
+    }
+}