src/imap/attributes.rs

@@ -1,4 +1,5 @@
 use imap_codec::imap_types::fetch::{MacroOrMessageDataItemNames, MessageDataItemName, Section};
+use imap_codec::imap_types::command::FetchModifier;
 
 /// Internal decisions based on fetched attributes
 /// passed by the client
@@ -7,7 +8,7 @@ pub struct AttributesProxy {
     pub attrs: Vec<MessageDataItemName<'static>>,
 }
 impl AttributesProxy {
-    pub fn new(attrs: &MacroOrMessageDataItemNames<'static>, is_uid_fetch: bool) -> Self {
+    pub fn new(attrs: &MacroOrMessageDataItemNames<'static>, modifiers: &[FetchModifier], is_uid_fetch: bool) -> Self {
         // Expand macros
         let mut fetch_attrs = match attrs {
             MacroOrMessageDataItemNames::Macro(m) => {
@@ -31,6 +32,14 @@ impl AttributesProxy {
             fetch_attrs.push(MessageDataItemName::Uid);
         }
 
+        // Handle inferred MODSEQ tag
+        let is_changed_since = modifiers
+            .iter()
+            .any(|m| matches!(m, FetchModifier::ChangedSince(..)));
+        if is_changed_since && !fetch_attrs.contains(&MessageDataItemName::ModSeq) {
+            fetch_attrs.push(MessageDataItemName::ModSeq);
+        }
+
         Self { attrs: fetch_attrs }
     }
 

src/imap/command/examined.rs

@@ -1,4 +1,5 @@
 use std::sync::Arc;
+use std::num::NonZeroU64;
 
 use anyhow::Result;
 use imap_codec::imap_types::command::{Command, CommandBody, FetchModifier};
@@ -11,7 +12,7 @@ use crate::imap::attributes::AttributesProxy;
 use crate::imap::capability::{ClientCapability, ServerCapability};
 use crate::imap::command::{anystate, authenticated};
 use crate::imap::flow;
-use crate::imap::mailbox_view::MailboxView;
+use crate::imap::mailbox_view::{MailboxView, UpdateParameters};
 use crate::imap::response::Response;
 use crate::mail::user::User;
 
@@ -93,9 +94,15 @@ impl<'a> ExaminedContext<'a> {
         modifiers: &[FetchModifier],
         uid: &bool,
     ) -> Result<(Response<'static>, flow::Transition)> {
-        let ap = AttributesProxy::new(attributes, *uid);
+        let ap = AttributesProxy::new(attributes, modifiers, *uid);
+        let mut changed_since: Option<NonZeroU64> = None;
+        modifiers.iter().for_each(|m| match m {
+            FetchModifier::ChangedSince(val) => {
+                changed_since = Some(*val);
+            },
+        });
 
-        match self.mailbox.fetch(sequence_set, &ap, uid).await {
+        match self.mailbox.fetch(sequence_set, &ap, changed_since, uid).await {
             Ok(resp) => {
                 // Capabilities enabling logic only on successful command
                 // (according to my understanding of the spec)
@@ -144,7 +151,7 @@ impl<'a> ExaminedContext<'a> {
     pub async fn noop(self) -> Result<(Response<'static>, flow::Transition)> {
         self.mailbox.internal.mailbox.force_sync().await?;
 
-        let updates = self.mailbox.update().await?;
+        let updates = self.mailbox.update(UpdateParameters::default()).await?;
         Ok((
             Response::build()
                 .to_req(self.req)

src/imap/command/selected.rs

@@ -1,4 +1,5 @@
 use std::sync::Arc;
+use std::num::NonZeroU64;
 
 use anyhow::Result;
 use imap_codec::imap_types::command::{Command, CommandBody, FetchModifier, StoreModifier};
@@ -13,7 +14,7 @@ use imap_codec::imap_types::sequence::SequenceSet;
 use crate::imap::capability::{ClientCapability, ServerCapability};
 use crate::imap::command::{anystate, authenticated, MailboxName};
 use crate::imap::flow;
-use crate::imap::mailbox_view::MailboxView;
+use crate::imap::mailbox_view::{MailboxView, UpdateParameters};
 use crate::imap::response::Response;
 use crate::imap::attributes::AttributesProxy;
 use crate::mail::user::User;
@@ -118,9 +119,15 @@ impl<'a> SelectedContext<'a> {
         modifiers: &[FetchModifier],
         uid: &bool,
     ) -> Result<(Response<'static>, flow::Transition)> {
-        let ap = AttributesProxy::new(attributes, *uid);
+        let ap = AttributesProxy::new(attributes, modifiers, *uid);
+        let mut changed_since: Option<NonZeroU64> = None;
+        modifiers.iter().for_each(|m| match m {
+            FetchModifier::ChangedSince(val) => {
+                changed_since = Some(*val);
+            },
+        });
 
-        match self.mailbox.fetch(sequence_set, &ap, uid).await {
+        match self.mailbox.fetch(sequence_set, &ap, changed_since, uid).await {
             Ok(resp) => {
                 // Capabilities enabling logic only on successful command
                 // (according to my understanding of the spec)
@@ -170,7 +177,7 @@ impl<'a> SelectedContext<'a> {
     pub async fn noop(self) -> Result<(Response<'static>, flow::Transition)> {
         self.mailbox.internal.mailbox.force_sync().await?;
 
-        let updates = self.mailbox.update().await?;
+        let updates = self.mailbox.update(UpdateParameters::default()).await?;
         Ok((
             Response::build()
                 .to_req(self.req)
@@ -204,10 +211,18 @@ impl<'a> SelectedContext<'a> {
         modifiers: &[StoreModifier],
         uid: &bool,
     ) -> Result<(Response<'static>, flow::Transition)> {
-        let data = self
+        let mut unchanged_since: Option<NonZeroU64> = None;
+        modifiers.iter().for_each(|m| match m {
+            StoreModifier::UnchangedSince(val) => {
+                unchanged_since = Some(*val);
+            },
+        });
+
+        let (data, modified) = self
             .mailbox
-            .store(sequence_set, kind, response, flags, uid)
+            .store(sequence_set, kind, response, flags, unchanged_since, uid)
             .await?;
+        let modified_str = format!("MODIFIED {}", modified.into_iter().map(|x| x.to_string()).collect::<Vec<_>>().join(","));
 
         self.client_capabilities.store_modifiers_enable(modifiers);
 
@@ -215,6 +230,7 @@ impl<'a> SelectedContext<'a> {
             Response::build()
                 .to_req(self.req)
                 .message("STORE completed")
+                .code(Code::Other(CodeOther::unvalidated(modified_str.into_bytes())))
                 .set_body(data)
                 .ok()?,
             flow::Transition::None,

src/imap/index.rs

@@ -1,4 +1,4 @@
-use std::num::NonZeroU32;
+use std::num::{NonZeroU32, NonZeroU64};
 
 use anyhow::{anyhow, Result};
 use imap_codec::imap_types::sequence::{SeqOrUid, Sequence, SequenceSet};
@@ -126,6 +126,36 @@ impl<'a> Index<'a> {
             _ => self.fetch_on_id(sequence_set),
         }
     }
+
+    pub fn fetch_changed_since(
+        self: &'a Index<'a>,
+        sequence_set: &SequenceSet,
+        maybe_modseq: Option<NonZeroU64>,
+        by_uid: bool,
+    ) -> Result<Vec<&'a MailIndex<'a>>> {
+        let raw = self.fetch(sequence_set, by_uid)?;
+        let res = match maybe_modseq {
+            Some(pit) => raw.into_iter().filter(|midx| midx.modseq > pit).collect(),
+            None => raw,
+        };
+
+        Ok(res)
+    }
+
+    pub fn fetch_unchanged_since(
+        self: &'a Index<'a>,
+        sequence_set: &SequenceSet,
+        maybe_modseq: Option<NonZeroU64>,
+        by_uid: bool,
+    ) -> Result<(Vec<&'a MailIndex<'a>>, Vec<&'a MailIndex<'a>>)> {
+        let raw = self.fetch(sequence_set, by_uid)?;
+        let res = match maybe_modseq {
+            Some(pit) => raw.into_iter().partition(|midx| midx.modseq <= pit),
+            None => (raw, vec![]),
+        };
+
+        Ok(res)
+    }
 }
 
 #[derive(Clone, Debug)]

src/imap/mailbox_view.rs

@@ -1,5 +1,6 @@
 use std::num::{NonZeroU32, NonZeroU64};
 use std::sync::Arc;
+use std::collections::HashSet;
 
 use anyhow::{anyhow, Error, Result};
 
@@ -12,6 +13,7 @@ use imap_codec::imap_types::response::{Code, CodeOther, Data, Status};
 use imap_codec::imap_types::search::SearchKey;
 use imap_codec::imap_types::sequence::SequenceSet;
 
+use crate::mail::unique_ident::UniqueIdent;
 use crate::mail::mailbox::Mailbox;
 use crate::mail::query::QueryScope;
 use crate::mail::snapshot::FrozenMailbox;
@@ -32,6 +34,21 @@ const DEFAULT_FLAGS: [Flag; 5] = [
     Flag::Draft,
 ];
 
+pub struct UpdateParameters {
+    pub silence: HashSet<UniqueIdent>,
+    pub with_modseq: bool,
+    pub with_uid: bool,
+}
+impl Default for UpdateParameters {
+    fn default() -> Self {
+        Self {
+            silence: HashSet::new(),
+            with_modseq: false,
+            with_uid: false,
+        }
+    }
+}
+
 /// A MailboxView is responsible for giving the client the information
 /// it needs about a mailbox, such as an initial summary of the mailbox's
 /// content and continuous updates indicating when the content
@@ -59,7 +76,7 @@ impl MailboxView {
     /// what the client knows and what is actually in the mailbox.
     /// This does NOT trigger a sync, it bases itself on what is currently
     /// loaded in RAM by Bayou.
-    pub async fn update(&mut self) -> Result<Vec<Body<'static>>> {
+    pub async fn update(&mut self, params: UpdateParameters) -> Result<Vec<Body<'static>>> {
         let old_snapshot = self.internal.update().await;
         let new_snapshot = &self.internal.snapshot;
 
@@ -105,19 +122,31 @@ impl MailboxView {
         } else {
             // - if flags changed for existing mails, tell client
             for (i, (_uid, uuid)) in new_snapshot.idx_by_uid.iter().enumerate() {
+                if params.silence.contains(uuid) {
+                    continue;
+                }
+
                 let old_mail = old_snapshot.table.get(uuid);
                 let new_mail = new_snapshot.table.get(uuid);
                 if old_mail.is_some() && old_mail != new_mail {
-                    if let Some((uid, _modseq, flags)) = new_mail {
+                    if let Some((uid, modseq, flags)) = new_mail {
+                        let mut items = vec![
+                            MessageDataItem::Flags(
+                                flags.iter().filter_map(|f| flags::from_str(f)).collect(),
+                            ),
+                        ];
+
+                        if params.with_uid {
+                            items.push(MessageDataItem::Uid(*uid));
+                        }
+
+                        if params.with_modseq {
+                            items.push(MessageDataItem::ModSeq(*modseq));
+                        }
+
                         data.push(Body::Data(Data::Fetch {
                             seq: NonZeroU32::try_from((i + 1) as u32).unwrap(),
-                            items: vec![
+                            items: items.try_into()?,
-                                MessageDataItem::Uid(*uid),
-                                MessageDataItem::Flags(
-                                    flags.iter().filter_map(|f| flags::from_str(f)).collect(),
-                                ),
-                            ]
-                            .try_into()?,
                         }));
                     }
                 }
@@ -149,17 +178,20 @@ impl MailboxView {
         &mut self,
         sequence_set: &SequenceSet,
         kind: &StoreType,
-        _response: &StoreResponse,
+        response: &StoreResponse,
         flags: &[Flag<'a>],
+        unchanged_since: Option<NonZeroU64>,
         is_uid_store: &bool,
-    ) -> Result<Vec<Body<'static>>> {
+    ) -> Result<(Vec<Body<'static>>, Vec<NonZeroU32>)> {
         self.internal.sync().await?;
 
         let flags = flags.iter().map(|x| x.to_string()).collect::<Vec<_>>();
 
         let idx = self.index()?;
-        let mails = idx.fetch(sequence_set, *is_uid_store)?;
+        let (editable, in_conflict) = idx
-        for mi in mails.iter() {
+            .fetch_unchanged_since(sequence_set, unchanged_since, *is_uid_store)?;
+
+        for mi in editable.iter() {
             match kind {
                 StoreType::Add => {
                     self.internal.mailbox.add_flags(mi.uuid, &flags[..]).await?;
@@ -173,8 +205,23 @@ impl MailboxView {
             }
         }
 
-        // @TODO: handle _response
+        let silence = match response {
-        self.update().await
+            StoreResponse::Answer => HashSet::new(),
+            StoreResponse::Silent => editable.iter().map(|midx| midx.uuid).collect(),
+        };
+
+        let conflict_id_or_uid = match is_uid_store {
+            true => in_conflict.into_iter().map(|midx| midx.uid).collect(),
+            _ => in_conflict.into_iter().map(|midx| midx.i).collect(),
+        };
+
+        let summary = self.update(UpdateParameters {
+            with_uid: *is_uid_store,
+            with_modseq: unchanged_since.is_some(),
+            silence,
+        }).await?;
+
+        Ok((summary, conflict_id_or_uid))
     }
 
     pub async fn expunge(&mut self) -> Result<Vec<Body<'static>>> {
@@ -192,7 +239,7 @@ impl MailboxView {
             self.internal.mailbox.delete(msg).await?;
         }
 
-        self.update().await
+        self.update(UpdateParameters::default()).await
     }
 
     pub async fn copy(
@@ -247,7 +294,10 @@ impl MailboxView {
             ret.push((mi.uid, dest_uid));
         }
 
-        let update = self.update().await?;
+        let update = self.update(UpdateParameters {
+            with_uid: *is_uid_copy,
+            ..UpdateParameters::default()
+        }).await?;
 
         Ok((to_state.uidvalidity, ret, update))
     }
@@ -258,6 +308,7 @@ impl MailboxView {
         &self,
         sequence_set: &SequenceSet,
         ap: &AttributesProxy,
+        changed_since: Option<NonZeroU64>,
         is_uid_fetch: &bool,
     ) -> Result<Vec<Body<'static>>> {
         // [1/6] Pre-compute data
@@ -270,7 +321,11 @@ impl MailboxView {
         };
         tracing::debug!("Query scope {:?}", query_scope);
         let idx = self.index()?;
-        let mail_idx_list = idx.fetch(sequence_set, *is_uid_fetch)?;
+        let mail_idx_list = idx.fetch_changed_since(
+            sequence_set, 
+            changed_since, 
+            *is_uid_fetch
+        )?;
 
         // [2/6] Fetch the emails
         let uuids = mail_idx_list