Merge pull request 'Implement imap-flow' (#34) from refactor/imap-flow into main

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/aerogramme/pulls/34

6 files changed, 573 insertions, 290 deletions

diff --git a/src/imap/command/anonymous.rs b/src/imap/command/anonymous.rs
index d258bd3..fbd10e9 100644
--- a/src/imap/command/anonymous.rs
+++ b/src/imap/command/anonymous.rs
@@ -1,92 +1,77 @@
-use anyhow::{Error, Result};
-use boitalettres::proto::{res::body::Data as Body, Request, Response};
-use imap_codec::types::command::CommandBody;
-use imap_codec::types::core::AString;
-use imap_codec::types::response::{Capability, Data, Status};
+use anyhow::Result;
+use imap_codec::imap_types::command::{Command, CommandBody};
+use imap_codec::imap_types::core::AString;
+use imap_codec::imap_types::secret::Secret;
 
+use crate::imap::command::anystate;
 use crate::imap::flow;
+use crate::imap::response::Response;
 use crate::login::ArcLoginProvider;
 use crate::mail::user::User;
 
 //--- dispatching
 
 pub struct AnonymousContext<'a> {
-    pub req: &'a Request,
-    pub login_provider: Option<&'a ArcLoginProvider>,
+    pub req: &'a Command<'static>,
+    pub login_provider: &'a ArcLoginProvider,
 }
 
-pub async fn dispatch(ctx: AnonymousContext<'_>) -> Result<(Response, flow::Transition)> {
-    match &ctx.req.command.body {
-        CommandBody::Noop => Ok((Response::ok("Noop completed.")?, flow::Transition::None)),
-        CommandBody::Capability => ctx.capability().await,
-        CommandBody::Logout => ctx.logout().await,
+pub async fn dispatch(ctx: AnonymousContext<'_>) -> Result<(Response<'static>, flow::Transition)> {
+    match &ctx.req.body {
+        // Any State
+        CommandBody::Noop => anystate::noop_nothing(ctx.req.tag.clone()),
+        CommandBody::Capability => anystate::capability(ctx.req.tag.clone()),
+        CommandBody::Logout => anystate::logout(),
+
+        // Specific to anonymous context (3 commands)
         CommandBody::Login { username, password } => ctx.login(username, password).await,
-        _ => Ok((Response::no("Command unavailable")?, flow::Transition::None)),
+        CommandBody::Authenticate { .. } => {
+            anystate::not_implemented(ctx.req.tag.clone(), "authenticate")
+        }
+        //StartTLS is not implemented for now, we will probably go full TLS.
+
+        // Collect other commands
+        _ => anystate::wrong_state(ctx.req.tag.clone()),
     }
 }
 
 //--- Command controllers, private
 
 impl<'a> AnonymousContext<'a> {
-    async fn capability(self) -> Result<(Response, flow::Transition)> {
-        let capabilities = vec![Capability::Imap4Rev1, Capability::Idle];
-        let res = Response::ok("Server capabilities")?.with_body(Data::Capability(capabilities));
-        Ok((res, flow::Transition::None))
-    }
-
     async fn login(
         self,
-        username: &AString,
-        password: &AString,
-    ) -> Result<(Response, flow::Transition)> {
+        username: &AString<'a>,
+        password: &Secret<AString<'a>>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
         let (u, p) = (
-            String::try_from(username.clone())?,
-            String::try_from(password.clone())?,
+            std::str::from_utf8(username.as_ref())?,
+            std::str::from_utf8(password.declassify().as_ref())?,
         );
         tracing::info!(user = %u, "command.login");
 
-        let login_provider = match &self.login_provider {
-            Some(lp) => lp,
-            None => {
-                return Ok((
-                    Response::no("Login command not available (already logged in)")?,
-                    flow::Transition::None,
-                ))
-            }
-        };
-
-        let creds = match login_provider.login(&u, &p).await {
+        let creds = match self.login_provider.login(&u, &p).await {
             Err(e) => {
                 tracing::debug!(error=%e, "authentication failed");
                 return Ok((
-                    Response::no("Authentication failed")?,
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Authentication failed")
+                        .no()?,
                     flow::Transition::None,
                 ));
             }
             Ok(c) => c,
         };
 
-        let user = User::new(u.clone(), creds).await?;
+        let user = User::new(u.to_string(), creds).await?;
 
         tracing::info!(username=%u, "connected");
         Ok((
-            Response::ok("Completed")?,
+            Response::build()
+                .to_req(self.req)
+                .message("Completed")
+                .ok()?,
             flow::Transition::Authenticate(user),
         ))
     }
-
-    // C: 10 logout
-    // S: * BYE Logging out
-    // S: 10 OK Logout completed.
-    async fn logout(self) -> Result<(Response, flow::Transition)> {
-        // @FIXME we should implement  From<Vec<Status>> and From<Vec<ImapStatus>> in
-        // boitalettres/src/proto/res/body.rs
-        Ok((
-            Response::ok("Logout completed")?.with_body(vec![Body::Status(
-                Status::bye(None, "Logging out")
-                    .map_err(|e| Error::msg(e).context("Unable to generate IMAP status"))?,
-            )]),
-            flow::Transition::Logout,
-        ))
-    }
 }
diff --git a/src/imap/command/anystate.rs b/src/imap/command/anystate.rs
new file mode 100644
index 0000000..42fe645
--- /dev/null
+++ b/src/imap/command/anystate.rs
@@ -0,0 +1,52 @@
+use anyhow::Result;
+use imap_codec::imap_types::core::{NonEmptyVec, Tag};
+use imap_codec::imap_types::response::{Capability, Data};
+
+use crate::imap::flow;
+use crate::imap::response::Response;
+
+pub(crate) fn capability(tag: Tag<'static>) -> Result<(Response<'static>, flow::Transition)> {
+    let capabilities: NonEmptyVec<Capability> =
+        (vec![Capability::Imap4Rev1, Capability::Idle]).try_into()?;
+    let res = Response::build()
+        .tag(tag)
+        .message("Server capabilities")
+        .data(Data::Capability(capabilities))
+        .ok()?;
+
+    Ok((res, flow::Transition::None))
+}
+
+pub(crate) fn noop_nothing(tag: Tag<'static>) -> Result<(Response<'static>, flow::Transition)> {
+    Ok((
+        Response::build().tag(tag).message("Noop completed.").ok()?,
+        flow::Transition::None,
+    ))
+}
+
+pub(crate) fn logout() -> Result<(Response<'static>, flow::Transition)> {
+    Ok((Response::bye()?, flow::Transition::Logout))
+}
+
+pub(crate) fn not_implemented<'a>(
+    tag: Tag<'a>,
+    what: &str,
+) -> Result<(Response<'a>, flow::Transition)> {
+    Ok((
+        Response::build()
+            .tag(tag)
+            .message(format!("Command not implemented {}", what))
+            .bad()?,
+        flow::Transition::None,
+    ))
+}
+
+pub(crate) fn wrong_state(tag: Tag<'static>) -> Result<(Response<'static>, flow::Transition)> {
+    Ok((
+        Response::build()
+            .tag(tag)
+            .message("Command not authorized in this state")
+            .bad()?,
+        flow::Transition::None,
+    ))
+}
diff --git a/src/imap/command/authenticated.rs b/src/imap/command/authenticated.rs
index 2deb723..1bb4c6d 100644
--- a/src/imap/command/authenticated.rs
+++ b/src/imap/command/authenticated.rs
@@ -2,37 +2,42 @@ use std::collections::BTreeMap;
 use std::sync::Arc;
 
 use anyhow::{anyhow, bail, Result};
-use boitalettres::proto::res::body::Data as Body;
-use boitalettres::proto::{Request, Response};
-use imap_codec::types::command::{CommandBody, StatusAttribute};
-use imap_codec::types::core::NonZeroBytes;
-use imap_codec::types::datetime::MyDateTime;
-use imap_codec::types::flag::{Flag, FlagNameAttribute};
-use imap_codec::types::mailbox::{ListMailbox, Mailbox as MailboxCodec};
-use imap_codec::types::response::{Code, Data, StatusAttributeValue};
-
-use crate::imap::command::anonymous;
+use imap_codec::imap_types::command::{Command, CommandBody};
+use imap_codec::imap_types::core::{Atom, Literal, QuotedChar};
+use imap_codec::imap_types::datetime::DateTime;
+use imap_codec::imap_types::flag::{Flag, FlagNameAttribute};
+use imap_codec::imap_types::mailbox::{ListMailbox, Mailbox as MailboxCodec};
+use imap_codec::imap_types::response::{Code, CodeOther, Data};
+use imap_codec::imap_types::status::{StatusDataItem, StatusDataItemName};
+
+use crate::imap::command::{anystate, MailboxName};
 use crate::imap::flow;
 use crate::imap::mailbox_view::MailboxView;
+use crate::imap::response::Response;
 
 use crate::mail::mailbox::Mailbox;
 use crate::mail::uidindex::*;
-use crate::mail::user::{User, INBOX, MAILBOX_HIERARCHY_DELIMITER};
+use crate::mail::user::{User, MAILBOX_HIERARCHY_DELIMITER as MBX_HIER_DELIM_RAW};
 use crate::mail::IMF;
 
 pub struct AuthenticatedContext<'a> {
-    pub req: &'a Request,
+    pub req: &'a Command<'static>,
     pub user: &'a Arc<User>,
 }
 
-pub async fn dispatch(ctx: AuthenticatedContext<'_>) -> Result<(Response, flow::Transition)> {
-    match &ctx.req.command.body {
+pub async fn dispatch<'a>(
+    ctx: AuthenticatedContext<'a>,
+) -> Result<(Response<'static>, flow::Transition)> {
+    match &ctx.req.body {
+        // Any state
+        CommandBody::Noop => anystate::noop_nothing(ctx.req.tag.clone()),
+        CommandBody::Capability => anystate::capability(ctx.req.tag.clone()),
+        CommandBody::Logout => anystate::logout(),
+
+        // Specific to this state (11 commands)
         CommandBody::Create { mailbox } => ctx.create(mailbox).await,
         CommandBody::Delete { mailbox } => ctx.delete(mailbox).await,
-        CommandBody::Rename {
-            mailbox,
-            new_mailbox,
-        } => ctx.rename(mailbox, new_mailbox).await,
+        CommandBody::Rename { from, to } => ctx.rename(from, to).await,
         CommandBody::Lsub {
             reference,
             mailbox_wildcard,
@@ -43,8 +48,8 @@ pub async fn dispatch(ctx: AuthenticatedContext<'_>) -> Result<(Response, flow::
         } => ctx.list(reference, mailbox_wildcard, false).await,
         CommandBody::Status {
             mailbox,
-            attributes,
-        } => ctx.status(mailbox, attributes).await,
+            item_names,
+        } => ctx.status(mailbox, item_names).await,
         CommandBody::Subscribe { mailbox } => ctx.subscribe(mailbox).await,
         CommandBody::Unsubscribe { mailbox } => ctx.unsubscribe(mailbox).await,
         CommandBody::Select { mailbox } => ctx.select(mailbox).await,
@@ -55,90 +60,148 @@ pub async fn dispatch(ctx: AuthenticatedContext<'_>) -> Result<(Response, flow::
             date,
             message,
         } => ctx.append(mailbox, flags, date, message).await,
-        _ => {
-            let ctx = anonymous::AnonymousContext {
-                req: ctx.req,
-                login_provider: None,
-            };
-            anonymous::dispatch(ctx).await
-        }
+
+        // Collect other commands
+        _ => anystate::wrong_state(ctx.req.tag.clone()),
     }
 }
 
 // --- PRIVATE ---
-
 impl<'a> AuthenticatedContext<'a> {
-    async fn create(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
-
-        if name == INBOX {
-            return Ok((
-                Response::bad("Cannot create INBOX")?,
-                flow::Transition::None,
-            ));
-        }
+    async fn create(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name = match mailbox {
+            MailboxCodec::Inbox => {
+                return Ok((
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Cannot create INBOX")
+                        .bad()?,
+                    flow::Transition::None,
+                ));
+            }
+            MailboxCodec::Other(aname) => std::str::from_utf8(aname.as_ref())?,
+        };
 
         match self.user.create_mailbox(&name).await {
-            Ok(()) => Ok((Response::ok("CREATE complete")?, flow::Transition::None)),
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
+            Ok(()) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message("CREATE complete")
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message(&e.to_string())
+                    .no()?,
+                flow::Transition::None,
+            )),
         }
     }
 
-    async fn delete(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    async fn delete(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         match self.user.delete_mailbox(&name).await {
-            Ok(()) => Ok((Response::ok("DELETE complete")?, flow::Transition::None)),
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
+            Ok(()) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message("DELETE complete")
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message(e.to_string())
+                    .no()?,
+                flow::Transition::None,
+            )),
         }
     }
 
     async fn rename(
         self,
-        mailbox: &MailboxCodec,
-        new_mailbox: &MailboxCodec,
-    ) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
-        let new_name = String::try_from(new_mailbox.clone())?;
+        from: &MailboxCodec<'a>,
+        to: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(from).try_into()?;
+        let new_name: &str = MailboxName(to).try_into()?;
 
         match self.user.rename_mailbox(&name, &new_name).await {
-            Ok(()) => Ok((Response::ok("RENAME complete")?, flow::Transition::None)),
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
+            Ok(()) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message("RENAME complete")
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message(e.to_string())
+                    .no()?,
+                flow::Transition::None,
+            )),
         }
     }
 
     async fn list(
         self,
-        reference: &MailboxCodec,
-        mailbox_wildcard: &ListMailbox,
+        reference: &MailboxCodec<'a>,
+        mailbox_wildcard: &ListMailbox<'a>,
         is_lsub: bool,
-    ) -> Result<(Response, flow::Transition)> {
-        let reference = String::try_from(reference.clone())?;
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let mbx_hier_delim: QuotedChar = QuotedChar::unvalidated(MBX_HIER_DELIM_RAW);
+
+        let reference: &str = MailboxName(reference).try_into()?;
         if !reference.is_empty() {
             return Ok((
-                Response::bad("References not supported")?,
+                Response::build()
+                    .to_req(self.req)
+                    .message("References not supported")
+                    .bad()?,
                 flow::Transition::None,
             ));
         }
 
-        let wildcard = String::try_from(mailbox_wildcard.clone())?;
+        // @FIXME would probably need a rewrite to better use the imap_codec library
+        let wildcard = match mailbox_wildcard {
+            ListMailbox::Token(v) => std::str::from_utf8(v.as_ref())?,
+            ListMailbox::String(v) => std::str::from_utf8(v.as_ref())?,
+        };
         if wildcard.is_empty() {
             if is_lsub {
                 return Ok((
-                    Response::ok("LSUB complete")?.with_body(vec![Data::Lsub {
-                        items: vec![],
-                        delimiter: Some(MAILBOX_HIERARCHY_DELIMITER),
-                        mailbox: "".try_into().unwrap(),
-                    }]),
+                    Response::build()
+                        .to_req(self.req)
+                        .message("LSUB complete")
+                        .data(Data::Lsub {
+                            items: vec![],
+                            delimiter: Some(mbx_hier_delim),
+                            mailbox: "".try_into().unwrap(),
+                        })
+                        .ok()?,
                     flow::Transition::None,
                 ));
             } else {
                 return Ok((
-                    Response::ok("LIST complete")?.with_body(vec![Data::List {
-                        items: vec![],
-                        delimiter: Some(MAILBOX_HIERARCHY_DELIMITER),
-                        mailbox: "".try_into().unwrap(),
-                    }]),
+                    Response::build()
+                        .to_req(self.req)
+                        .message("LIST complete")
+                        .data(Data::List {
+                            items: vec![],
+                            delimiter: Some(mbx_hier_delim),
+                            mailbox: "".try_into().unwrap(),
+                        })
+                        .ok()?,
                     flow::Transition::None,
                 ));
             }
@@ -147,7 +210,7 @@ impl<'a> AuthenticatedContext<'a> {
         let mailboxes = self.user.list_mailboxes().await?;
         let mut vmailboxes = BTreeMap::new();
         for mb in mailboxes.iter() {
-            for (i, _) in mb.match_indices(MAILBOX_HIERARCHY_DELIMITER) {
+            for (i, _) in mb.match_indices(MBX_HIER_DELIM_RAW) {
                 if i > 0 {
                     let smb = &mb[..i];
                     vmailboxes.entry(smb).or_insert(false);
@@ -163,22 +226,22 @@ impl<'a> AuthenticatedContext<'a> {
                     .to_string()
                     .try_into()
                     .map_err(|_| anyhow!("invalid mailbox name"))?;
-                let mut items = vec![FlagNameAttribute::Extension(
-                    "Subscribed".try_into().unwrap(),
-                )];
+                let mut items = vec![FlagNameAttribute::try_from(Atom::unvalidated(
+                    "Subscribed",
+                ))?];
                 if !*is_real {
                     items.push(FlagNameAttribute::Noselect);
                 }
                 if is_lsub {
                     ret.push(Data::Lsub {
                         items,
-                        delimiter: Some(MAILBOX_HIERARCHY_DELIMITER),
+                        delimiter: Some(mbx_hier_delim),
                         mailbox,
                     });
                 } else {
                     ret.push(Data::List {
                         items,
-                        delimiter: Some(MAILBOX_HIERARCHY_DELIMITER),
+                        delimiter: Some(mbx_hier_delim),
                         mailbox,
                     });
                 }
@@ -190,79 +253,120 @@ impl<'a> AuthenticatedContext<'a> {
         } else {
             "LIST completed"
         };
-        Ok((Response::ok(msg)?.with_body(ret), flow::Transition::None))
+        Ok((
+            Response::build()
+                .to_req(self.req)
+                .message(msg)
+                .many_data(ret)
+                .ok()?,
+            flow::Transition::None,
+        ))
     }
 
     async fn status(
         self,
-        mailbox: &MailboxCodec,
-        attributes: &[StatusAttribute],
-    ) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
-        let mb_opt = self.user.open_mailbox(&name).await?;
+        mailbox: &MailboxCodec<'static>,
+        attributes: &[StatusDataItemName],
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
+        let mb_opt = self.user.open_mailbox(name).await?;
         let mb = match mb_opt {
             Some(mb) => mb,
             None => {
                 return Ok((
-                    Response::no("Mailbox does not exist")?,
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Mailbox does not exist")
+                        .no()?,
                     flow::Transition::None,
                 ))
             }
         };
 
-        let (view, _data) = MailboxView::new(mb).await?;
+        let view = MailboxView::new(mb).await;
 
         let mut ret_attrs = vec![];
         for attr in attributes.iter() {
             ret_attrs.push(match attr {
-                StatusAttribute::Messages => StatusAttributeValue::Messages(view.exists()?),
-                StatusAttribute::Unseen => StatusAttributeValue::Unseen(view.unseen_count() as u32),
-                StatusAttribute::Recent => StatusAttributeValue::Recent(view.recent()?),
-                StatusAttribute::UidNext => StatusAttributeValue::UidNext(view.uidnext()),
-                StatusAttribute::UidValidity => {
-                    StatusAttributeValue::UidValidity(view.uidvalidity())
+                StatusDataItemName::Messages => StatusDataItem::Messages(view.exists()?),
+                StatusDataItemName::Unseen => StatusDataItem::Unseen(view.unseen_count() as u32),
+                StatusDataItemName::Recent => StatusDataItem::Recent(view.recent()?),
+                StatusDataItemName::UidNext => StatusDataItem::UidNext(view.uidnext()),
+                StatusDataItemName::UidValidity => {
+                    StatusDataItem::UidValidity(view.uidvalidity())
                 }
+                StatusDataItemName::Deleted => {
+                    bail!("quota not implemented, can't return deleted elements waiting for EXPUNGE");
+                },
+                StatusDataItemName::DeletedStorage => {
+                    bail!("quota not implemented, can't return freed storage after EXPUNGE will be run");
+                },
             });
         }
 
-        let data = vec![Body::Data(Data::Status {
+        let data = Data::Status {
             mailbox: mailbox.clone(),
-            attributes: ret_attrs,
-        })];
+            items: ret_attrs.into(),
+        };
 
         Ok((
-            Response::ok("STATUS completed")?.with_body(data),
+            Response::build()
+                .to_req(self.req)
+                .message("STATUS completed")
+                .data(data)
+                .ok()?,
             flow::Transition::None,
         ))
     }
 
-    async fn subscribe(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    async fn subscribe(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         if self.user.has_mailbox(&name).await? {
-            Ok((Response::ok("SUBSCRIBE complete")?, flow::Transition::None))
+            Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message("SUBSCRIBE complete")
+                    .ok()?,
+                flow::Transition::None,
+            ))
         } else {
             Ok((
-                Response::bad(&format!("Mailbox {} does not exist", name))?,
+                Response::build()
+                    .to_req(self.req)
+                    .message(format!("Mailbox {} does not exist", name))
+                    .bad()?,
                 flow::Transition::None,
             ))
         }
     }
 
-    async fn unsubscribe(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    async fn unsubscribe(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         if self.user.has_mailbox(&name).await? {
             Ok((
-                Response::bad(&format!(
-                    "Cannot unsubscribe from mailbox {}: not supported by Aerogramme",
-                    name
-                ))?,
+                Response::build()
+                    .to_req(self.req)
+                    .message(format!(
+                        "Cannot unsubscribe from mailbox {}: not supported by Aerogramme",
+                        name
+                    ))
+                    .bad()?,
                 flow::Transition::None,
             ))
         } else {
             Ok((
-                Response::bad(&format!("Mailbox {} does not exist", name))?,
+                Response::build()
+                    .to_req(self.req)
+                    .message(format!("Mailbox {} does not exist", name))
+                    .no()?,
                 flow::Transition::None,
             ))
         }
@@ -301,83 +405,113 @@ impl<'a> AuthenticatedContext<'a> {
 
     * TRACE END ---
     */
-    async fn select(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    async fn select(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         let mb_opt = self.user.open_mailbox(&name).await?;
         let mb = match mb_opt {
             Some(mb) => mb,
             None => {
                 return Ok((
-                    Response::no("Mailbox does not exist")?,
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Mailbox does not exist")
+                        .no()?,
                     flow::Transition::None,
                 ))
             }
         };
         tracing::info!(username=%self.user.username, mailbox=%name, "mailbox.selected");
 
-        let (mb, data) = MailboxView::new(mb).await?;
+        let mb = MailboxView::new(mb).await;
+        let data = mb.summary()?;
 
         Ok((
-            Response::ok("Select completed")?
-                .with_extra_code(Code::ReadWrite)
-                .with_body(data),
+            Response::build()
+                .message("Select completed")
+                .to_req(self.req)
+                .code(Code::ReadWrite)
+                .set_body(data)
+                .ok()?,
             flow::Transition::Select(mb),
         ))
     }
 
-    async fn examine(self, mailbox: &MailboxCodec) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    async fn examine(
+        self,
+        mailbox: &MailboxCodec<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         let mb_opt = self.user.open_mailbox(&name).await?;
         let mb = match mb_opt {
             Some(mb) => mb,
             None => {
                 return Ok((
-                    Response::no("Mailbox does not exist")?,
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Mailbox does not exist")
+                        .no()?,
                     flow::Transition::None,
                 ))
             }
         };
         tracing::info!(username=%self.user.username, mailbox=%name, "mailbox.examined");
 
-        let (mb, data) = MailboxView::new(mb).await?;
+        let mb = MailboxView::new(mb).await;
+        let data = mb.summary()?;
 
         Ok((
-            Response::ok("Examine completed")?
-                .with_extra_code(Code::ReadOnly)
-                .with_body(data),
+            Response::build()
+                .to_req(self.req)
+                .message("Examine completed")
+                .code(Code::ReadOnly)
+                .set_body(data)
+                .ok()?,
             flow::Transition::Examine(mb),
         ))
     }
 
     async fn append(
         self,
-        mailbox: &MailboxCodec,
-        flags: &[Flag],
-        date: &Option<MyDateTime>,
-        message: &NonZeroBytes,
-    ) -> Result<(Response, flow::Transition)> {
+        mailbox: &MailboxCodec<'a>,
+        flags: &[Flag<'a>],
+        date: &Option<DateTime>,
+        message: &Literal<'a>,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let append_tag = self.req.tag.clone();
         match self.append_internal(mailbox, flags, date, message).await {
             Ok((_mb, uidvalidity, uid)) => Ok((
-                Response::ok("APPEND completed")?.with_extra_code(Code::Other(
-                    "APPENDUID".try_into().unwrap(),
-                    Some(format!("{} {}", uidvalidity, uid)),
-                )),
+                Response::build()
+                    .tag(append_tag)
+                    .message("APPEND completed")
+                    .code(Code::Other(CodeOther::unvalidated(
+                        format!("APPENDUID {} {}", uidvalidity, uid).into_bytes(),
+                    )))
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .tag(append_tag)
+                    .message(e.to_string())
+                    .no()?,
                 flow::Transition::None,
             )),
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
         }
     }
 
     pub(crate) async fn append_internal(
         self,
-        mailbox: &MailboxCodec,
-        flags: &[Flag],
-        date: &Option<MyDateTime>,
-        message: &NonZeroBytes,
+        mailbox: &MailboxCodec<'a>,
+        flags: &[Flag<'a>],
+        date: &Option<DateTime>,
+        message: &Literal<'a>,
     ) -> Result<(Arc<Mailbox>, ImapUidvalidity, ImapUidvalidity)> {
-        let name = String::try_from(mailbox.clone())?;
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         let mb_opt = self.user.open_mailbox(&name).await?;
         let mb = match mb_opt {
@@ -389,8 +523,8 @@ impl<'a> AuthenticatedContext<'a> {
             bail!("Cannot set date when appending message");
         }
 
-        let msg = IMF::try_from(message.as_slice())
-            .map_err(|_| anyhow!("Could not parse e-mail message"))?;
+        let msg =
+            IMF::try_from(message.data()).map_err(|_| anyhow!("Could not parse e-mail message"))?;
         let flags = flags.iter().map(|x| x.to_string()).collect::<Vec<_>>();
         // TODO: filter allowed flags? ping @Quentin
 
@@ -422,7 +556,7 @@ fn matches_wildcard(wildcard: &str, name: &str) -> bool {
                     && j > 0
                     && matches[i - 1][j]
                     && (wildcard[j - 1] == '*'
-                        || (wildcard[j - 1] == '%' && name[i - 1] != MAILBOX_HIERARCHY_DELIMITER)));
+                        || (wildcard[j - 1] == '%' && name[i - 1] != MBX_HIER_DELIM_RAW)));
         }
     }
 
diff --git a/src/imap/command/examined.rs b/src/imap/command/examined.rs
index 1740b39..7de94f4 100644
--- a/src/imap/command/examined.rs
+++ b/src/imap/command/examined.rs
@@ -1,56 +1,60 @@
 use std::sync::Arc;
 
 use anyhow::Result;
-use boitalettres::proto::Request;
-use boitalettres::proto::Response;
-use imap_codec::types::command::{CommandBody, SearchKey};
-use imap_codec::types::core::{Charset, NonZeroBytes};
-use imap_codec::types::datetime::MyDateTime;
-use imap_codec::types::fetch_attributes::MacroOrFetchAttributes;
-use imap_codec::types::flag::Flag;
-use imap_codec::types::mailbox::Mailbox as MailboxCodec;
-use imap_codec::types::response::Code;
-use imap_codec::types::sequence::SequenceSet;
+use imap_codec::imap_types::command::{Command, CommandBody};
+use imap_codec::imap_types::core::Charset;
+use imap_codec::imap_types::fetch::MacroOrMessageDataItemNames;
+use imap_codec::imap_types::search::SearchKey;
+use imap_codec::imap_types::sequence::SequenceSet;
 
-use crate::imap::command::authenticated;
+use crate::imap::command::{anystate, authenticated};
 use crate::imap::flow;
 use crate::imap::mailbox_view::MailboxView;
+use crate::imap::response::Response;
 use crate::mail::user::User;
 
 pub struct ExaminedContext<'a> {
-    pub req: &'a Request,
+    pub req: &'a Command<'static>,
     pub user: &'a Arc<User>,
     pub mailbox: &'a mut MailboxView,
 }
 
-pub async fn dispatch(ctx: ExaminedContext<'_>) -> Result<(Response, flow::Transition)> {
-    match &ctx.req.command.body {
-        // CLOSE in examined state is not the same as in selected state
-        // (in selected state it also does an EXPUNGE, here it doesn't)
+pub async fn dispatch(ctx: ExaminedContext<'_>) -> Result<(Response<'static>, flow::Transition)> {
+    match &ctx.req.body {
+        // Any State
+        // noop is specific to this state
+        CommandBody::Capability => anystate::capability(ctx.req.tag.clone()),
+        CommandBody::Logout => anystate::logout(),
+
+        // Specific to the EXAMINE state (specialization of the SELECTED state)
+        // ~3 commands -> close, fetch, search + NOOP
         CommandBody::Close => ctx.close().await,
         CommandBody::Fetch {
             sequence_set,
-            attributes,
+            macro_or_item_names,
             uid,
-        } => ctx.fetch(sequence_set, attributes, uid).await,
+        } => ctx.fetch(sequence_set, macro_or_item_names, uid).await,
         CommandBody::Search {
             charset,
             criteria,
             uid,
         } => ctx.search(charset, criteria, uid).await,
-        CommandBody::Noop => ctx.noop().await,
-        CommandBody::Append {
-            mailbox,
-            flags,
-            date,
-            message,
-        } => ctx.append(mailbox, flags, date, message).await,
+        CommandBody::Noop | CommandBody::Check => ctx.noop().await,
+        CommandBody::Expunge { .. } | CommandBody::Store { .. } => Ok((
+            Response::build()
+                .to_req(ctx.req)
+                .message("Forbidden command: can't write in read-only mode (EXAMINE)")
+                .bad()?,
+            flow::Transition::None,
+        )),
+
+        // In examined mode, we fallback to authenticated when needed
         _ => {
-            let ctx = authenticated::AuthenticatedContext {
+            authenticated::dispatch(authenticated::AuthenticatedContext {
                 req: ctx.req,
                 user: ctx.user,
-            };
-            authenticated::dispatch(ctx).await
+            })
+            .await
         }
     }
 }
@@ -58,71 +62,69 @@ pub async fn dispatch(ctx: ExaminedContext<'_>) -> Result<(Response, flow::Trans
 // --- PRIVATE ---
 
 impl<'a> ExaminedContext<'a> {
-    async fn close(self) -> Result<(Response, flow::Transition)> {
-        Ok((Response::ok("CLOSE completed")?, flow::Transition::Unselect))
+    /// CLOSE in examined state is not the same as in selected state
+    /// (in selected state it also does an EXPUNGE, here it doesn't)
+    async fn close(self) -> Result<(Response<'static>, flow::Transition)> {
+        Ok((
+            Response::build()
+                .to_req(self.req)
+                .message("CLOSE completed")
+                .ok()?,
+            flow::Transition::Unselect,
+        ))
     }
 
     pub async fn fetch(
         self,
         sequence_set: &SequenceSet,
-        attributes: &MacroOrFetchAttributes,
+        attributes: &'a MacroOrMessageDataItemNames<'static>,
         uid: &bool,
-    ) -> Result<(Response, flow::Transition)> {
+    ) -> Result<(Response<'static>, flow::Transition)> {
         match self.mailbox.fetch(sequence_set, attributes, uid).await {
             Ok(resp) => Ok((
-                Response::ok("FETCH completed")?.with_body(resp),
+                Response::build()
+                    .to_req(self.req)
+                    .message("FETCH completed")
+                    .set_body(resp)
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message(e.to_string())
+                    .no()?,
                 flow::Transition::None,
             )),
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
         }
     }
 
     pub async fn search(
         self,
-        _charset: &Option<Charset>,
-        _criteria: &SearchKey,
+        _charset: &Option<Charset<'a>>,
+        _criteria: &SearchKey<'a>,
         _uid: &bool,
-    ) -> Result<(Response, flow::Transition)> {
-        Ok((Response::bad("Not implemented")?, flow::Transition::None))
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        Ok((
+            Response::build()
+                .to_req(self.req)
+                .message("Not implemented")
+                .bad()?,
+            flow::Transition::None,
+        ))
     }
 
-    pub async fn noop(self) -> Result<(Response, flow::Transition)> {
+    pub async fn noop(self) -> Result<(Response<'static>, flow::Transition)> {
         self.mailbox.mailbox.force_sync().await?;
 
         let updates = self.mailbox.update().await?;
         Ok((
-            Response::ok("NOOP completed.")?.with_body(updates),
+            Response::build()
+                .to_req(self.req)
+                .message("NOOP completed.")
+                .set_body(updates)
+                .ok()?,
             flow::Transition::None,
         ))
     }
-
-    async fn append(
-        self,
-        mailbox: &MailboxCodec,
-        flags: &[Flag],
-        date: &Option<MyDateTime>,
-        message: &NonZeroBytes,
-    ) -> Result<(Response, flow::Transition)> {
-        let ctx2 = authenticated::AuthenticatedContext {
-            req: self.req,
-            user: self.user,
-        };
-
-        match ctx2.append_internal(mailbox, flags, date, message).await {
-            Ok((mb, uidvalidity, uid)) => {
-                let resp = Response::ok("APPEND completed")?.with_extra_code(Code::Other(
-                    "APPENDUID".try_into().unwrap(),
-                    Some(format!("{} {}", uidvalidity, uid)),
-                ));
-
-                if Arc::ptr_eq(&mb, &self.mailbox.mailbox) {
-                    let data = self.mailbox.update().await?;
-                    Ok((resp.with_body(data), flow::Transition::None))
-                } else {
-                    Ok((resp, flow::Transition::None))
-                }
-            }
-            Err(e) => Ok((Response::no(&e.to_string())?, flow::Transition::None)),
-        }
-    }
 }
diff --git a/src/imap/command/mod.rs b/src/imap/command/mod.rs
index 0b7e576..dc95746 100644
--- a/src/imap/command/mod.rs
+++ b/src/imap/command/mod.rs
@@ -1,4 +1,21 @@
 pub mod anonymous;
+pub mod anystate;
 pub mod authenticated;
 pub mod examined;
 pub mod selected;
+
+use crate::mail::user::INBOX;
+use imap_codec::imap_types::mailbox::Mailbox as MailboxCodec;
+
+/// Convert an IMAP mailbox name/identifier representation
+/// to an utf-8 string that is used internally in Aerogramme
+struct MailboxName<'a>(&'a MailboxCodec<'a>);
+impl<'a> TryInto<&'a str> for MailboxName<'a> {
+    type Error = std::str::Utf8Error;
+    fn try_into(self) -> Result<&'a str, Self::Error> {
+        match self.0 {
+            MailboxCodec::Inbox => Ok(INBOX),
+            MailboxCodec::Other(aname) => Ok(std::str::from_utf8(aname.as_ref())?),
+        }
+    }
+}
diff --git a/src/imap/command/selected.rs b/src/imap/command/selected.rs
index 90a00ee..220a952 100644
--- a/src/imap/command/selected.rs
+++ b/src/imap/command/selected.rs
@@ -1,31 +1,50 @@
 use std::sync::Arc;
 
 use anyhow::Result;
-use boitalettres::proto::Request;
-use boitalettres::proto::Response;
-use imap_codec::types::command::CommandBody;
-use imap_codec::types::flag::{Flag, StoreResponse, StoreType};
-use imap_codec::types::mailbox::Mailbox as MailboxCodec;
-use imap_codec::types::response::Code;
-use imap_codec::types::sequence::SequenceSet;
-
-use crate::imap::command::examined;
+use imap_codec::imap_types::command::{Command, CommandBody};
+use imap_codec::imap_types::core::Charset;
+use imap_codec::imap_types::fetch::MacroOrMessageDataItemNames;
+use imap_codec::imap_types::flag::{Flag, StoreResponse, StoreType};
+use imap_codec::imap_types::mailbox::Mailbox as MailboxCodec;
+use imap_codec::imap_types::response::{Code, CodeOther};
+use imap_codec::imap_types::search::SearchKey;
+use imap_codec::imap_types::sequence::SequenceSet;
+
+use crate::imap::command::{anystate, authenticated, MailboxName};
 use crate::imap::flow;
 use crate::imap::mailbox_view::MailboxView;
+use crate::imap::response::Response;
 
 use crate::mail::user::User;
 
 pub struct SelectedContext<'a> {
-    pub req: &'a Request,
+    pub req: &'a Command<'static>,
     pub user: &'a Arc<User>,
     pub mailbox: &'a mut MailboxView,
 }
 
-pub async fn dispatch(ctx: SelectedContext<'_>) -> Result<(Response, flow::Transition)> {
-    match &ctx.req.command.body {
-        // Only write commands here, read commands are handled in
-        // `examined.rs`
+pub async fn dispatch<'a>(
+    ctx: SelectedContext<'a>,
+) -> Result<(Response<'static>, flow::Transition)> {
+    match &ctx.req.body {
+        // Any State
+        // noop is specific to this state
+        CommandBody::Capability => anystate::capability(ctx.req.tag.clone()),
+        CommandBody::Logout => anystate::logout(),
+
+        // Specific to this state (7 commands + NOOP)
         CommandBody::Close => ctx.close().await,
+        CommandBody::Noop | CommandBody::Check => ctx.noop().await,
+        CommandBody::Fetch {
+            sequence_set,
+            macro_or_item_names,
+            uid,
+        } => ctx.fetch(sequence_set, macro_or_item_names, uid).await,
+        CommandBody::Search {
+            charset,
+            criteria,
+            uid,
+        } => ctx.search(charset, criteria, uid).await,
         CommandBody::Expunge => ctx.expunge().await,
         CommandBody::Store {
             sequence_set,
@@ -39,13 +58,14 @@ pub async fn dispatch(ctx: SelectedContext<'_>) -> Result<(Response, flow::Trans
             mailbox,
             uid,
         } => ctx.copy(sequence_set, mailbox, uid).await,
+
+        // In selected mode, we fallback to authenticated when needed
         _ => {
-            let ctx = examined::ExaminedContext {
+            authenticated::dispatch(authenticated::AuthenticatedContext {
                 req: ctx.req,
                 user: ctx.user,
-                mailbox: ctx.mailbox,
-            };
-            examined::dispatch(ctx).await
+            })
+            .await
         }
     }
 }
@@ -53,18 +73,81 @@ pub async fn dispatch(ctx: SelectedContext<'_>) -> Result<(Response, flow::Trans
 // --- PRIVATE ---
 
 impl<'a> SelectedContext<'a> {
-    async fn close(self) -> Result<(Response, flow::Transition)> {
+    async fn close(self) -> Result<(Response<'static>, flow::Transition)> {
         // We expunge messages,
         // but we don't send the untagged EXPUNGE responses
+        let tag = self.req.tag.clone();
         self.expunge().await?;
-        Ok((Response::ok("CLOSE completed")?, flow::Transition::Unselect))
+        Ok((
+            Response::build().tag(tag).message("CLOSE completed").ok()?,
+            flow::Transition::Unselect,
+        ))
+    }
+
+    pub async fn fetch(
+        self,
+        sequence_set: &SequenceSet,
+        attributes: &'a MacroOrMessageDataItemNames<'static>,
+        uid: &bool,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        match self.mailbox.fetch(sequence_set, attributes, uid).await {
+            Ok(resp) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message("FETCH completed")
+                    .set_body(resp)
+                    .ok()?,
+                flow::Transition::None,
+            )),
+            Err(e) => Ok((
+                Response::build()
+                    .to_req(self.req)
+                    .message(e.to_string())
+                    .no()?,
+                flow::Transition::None,
+            )),
+        }
+    }
+
+    pub async fn search(
+        self,
+        _charset: &Option<Charset<'a>>,
+        _criteria: &SearchKey<'a>,
+        _uid: &bool,
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        Ok((
+            Response::build()
+                .to_req(self.req)
+                .message("Not implemented")
+                .bad()?,
+            flow::Transition::None,
+        ))
     }
 
-    async fn expunge(self) -> Result<(Response, flow::Transition)> {
+    pub async fn noop(self) -> Result<(Response<'static>, flow::Transition)> {
+        self.mailbox.mailbox.force_sync().await?;
+
+        let updates = self.mailbox.update().await?;
+        Ok((
+            Response::build()
+                .to_req(self.req)
+                .message("NOOP completed.")
+                .set_body(updates)
+                .ok()?,
+            flow::Transition::None,
+        ))
+    }
+
+    async fn expunge(self) -> Result<(Response<'static>, flow::Transition)> {
+        let tag = self.req.tag.clone();
         let data = self.mailbox.expunge().await?;
 
         Ok((
-            Response::ok("EXPUNGE completed")?.with_body(data),
+            Response::build()
+                .tag(tag)
+                .message("EXPUNGE completed")
+                .set_body(data)
+                .ok()?,
             flow::Transition::None,
         ))
     }
@@ -74,16 +157,20 @@ impl<'a> SelectedContext<'a> {
         sequence_set: &SequenceSet,
         kind: &StoreType,
         response: &StoreResponse,
-        flags: &[Flag],
+        flags: &[Flag<'a>],
         uid: &bool,
-    ) -> Result<(Response, flow::Transition)> {
+    ) -> Result<(Response<'static>, flow::Transition)> {
         let data = self
             .mailbox
             .store(sequence_set, kind, response, flags, uid)
             .await?;
 
         Ok((
-            Response::ok("STORE completed")?.with_body(data),
+            Response::build()
+                .to_req(self.req)
+                .message("STORE completed")
+                .set_body(data)
+                .ok()?,
             flow::Transition::None,
         ))
     }
@@ -91,18 +178,21 @@ impl<'a> SelectedContext<'a> {
     async fn copy(
         self,
         sequence_set: &SequenceSet,
-        mailbox: &MailboxCodec,
+        mailbox: &MailboxCodec<'a>,
         uid: &bool,
-    ) -> Result<(Response, flow::Transition)> {
-        let name = String::try_from(mailbox.clone())?;
+    ) -> Result<(Response<'static>, flow::Transition)> {
+        let name: &str = MailboxName(mailbox).try_into()?;
 
         let mb_opt = self.user.open_mailbox(&name).await?;
         let mb = match mb_opt {
             Some(mb) => mb,
             None => {
                 return Ok((
-                    Response::no("Destination mailbox does not exist")?
-                        .with_extra_code(Code::TryCreate),
+                    Response::build()
+                        .to_req(self.req)
+                        .message("Destination mailbox does not exist")
+                        .code(Code::TryCreate)
+                        .no()?,
                     flow::Transition::None,
                 ))
             }
@@ -126,10 +216,13 @@ impl<'a> SelectedContext<'a> {
         );
 
         Ok((
-            Response::ok("COPY completed")?.with_extra_code(Code::Other(
-                "COPYUID".try_into().unwrap(),
-                Some(copyuid_str),
-            )),
+            Response::build()
+                .to_req(self.req)
+                .message("COPY completed")
+                .code(Code::Other(CodeOther::unvalidated(
+                    format!("COPYUID {}", copyuid_str).into_bytes(),
+                )))
+                .ok()?,
             flow::Transition::None,
         ))
     }