feat: detect XCHATMAIL capability and expose it as is_chatmail config

deltachat-ffi/deltachat.h

@@ -517,6 +517,7 @@ char*           dc_get_blobdir               (const dc_context_t* context);
  *                    0=Nothing else happens when the key changes.
  *                    1=After the key changed, `dc_chat_can_send()` returns false and `dc_chat_is_protection_broken()` returns true
  *                    until `dc_accept_chat()` is called.
+ * - `is_chatmail` = 1 if the the server is a chatmail server, 0 otherwise.
  * - `ui.*`         = All keys prefixed by `ui.` can be used by the user-interfaces for system-specific purposes.
  *                    The prefix should be followed by the system and maybe subsystem,
  *                    e.g. `ui.desktop.foo`, `ui.desktop.linux.bar`, `ui.android.foo`, `ui.dc40.bar`, `ui.bot.simplebot.baz`.

src/config.rs

@@ -254,6 +254,9 @@ pub enum Config {
     /// True if account is configured.
     Configured,
 
+    /// True if account is a chatmail account.
+    IsChatmail,
+
     /// All secondary self addresses separated by spaces
     /// (`addr1@example.org addr2@example.org addr3@example.org`)
     SecondaryAddrs,

src/configure.rs

@@ -112,6 +112,11 @@ impl Context {
 
         let mut param = LoginParam::load_candidate_params(self).await?;
         let old_addr = self.get_config(Config::ConfiguredAddr).await?;
+
+        // Reset our knowledge about whether the server is a chatmail server.
+        // We will update it when we connect to IMAP.
+        self.set_config_internal(Config::IsChatmail, None).await?;
+
         let success = configure(self, &mut param).await;
         self.set_config_internal(Config::NotifyAboutWrongPw, None)
             .await?;
@@ -453,6 +458,10 @@ async fn configure(ctx: &Context, param: &mut LoginParam) -> Result<()> {
 
     progress!(ctx, 900);
 
+    if imap_session.is_chatmail() {
+        ctx.set_config(Config::MvboxMove, Some("0")).await?;
+    }
+
     let create_mvbox = ctx.should_watch_mvbox().await?;
 
     imap.configure_folders(ctx, &mut imap_session, create_mvbox)

src/context.rs

@@ -461,18 +461,10 @@ impl Context {
             return;
         }
 
-        {
-            if self
-                .get_config(Config::ConfiguredAddr)
-                .await
-                .unwrap_or_default()
-                .filter(|s| s.ends_with(".testrun.org"))
-                .is_some()
-            {
-                let mut lock = self.ratelimit.write().await;
-                // Allow at least 1 message every second + a burst of 3.
-                *lock = Ratelimit::new(Duration::new(3, 0), 3.0);
-            }
+        if self.is_chatmail().await.unwrap_or_default() {
+            let mut lock = self.ratelimit.write().await;
+            // Allow at least 1 message every second + a burst of 3.
+            *lock = Ratelimit::new(Duration::new(3, 0), 3.0);
         }
         self.scheduler.start(self.clone()).await;
     }
@@ -493,6 +485,11 @@ impl Context {
         self.scheduler.maybe_network().await;
     }
 
+    /// Returns true if an account is on a chatmail server.
+    pub async fn is_chatmail(&self) -> Result<bool> {
+        self.get_config_bool(Config::IsChatmail).await
+    }
+
     /// Does a background fetch
     /// pauses the scheduler and does one imap fetch, then unpauses and returns
     pub async fn background_fetch(&self) -> Result<()> {
@@ -799,6 +796,8 @@ impl Context {
             res.insert("imap_server_id", format!("{server_id:?}"));
         }
 
+        res.insert("is_chatmail", self.is_chatmail().await?.to_string());
+
         if let Some(metadata) = &*self.metadata.read().await {
             if let Some(comment) = &metadata.comment {
                 res.insert("imap_server_comment", format!("{comment:?}"));

src/imap/capabilities.rs

@@ -32,6 +32,14 @@ pub(crate) struct Capabilities {
     /// This is supported by <https://github.com/deltachat/chatmail>
     pub can_push: bool,
 
+    /// True if the server has an XCHATMAIL capability
+    /// indicating that it is a <https://github.com/deltachat/chatmail> server.
+    ///
+    /// This can be used to hide some advanced settings in the UI
+    /// that are only interesting for normal email accounts,
+    /// e.g. the ability to move messages to Delta Chat folder.
+    pub is_chatmail: bool,
+
     /// Server ID if the server supports ID capability.
     pub server_id: Option<HashMap<String, String>>,
 }

src/imap/client.rs

@@ -61,6 +61,7 @@ async fn determine_capabilities(
         can_condstore: caps.has_str("CONDSTORE"),
         can_metadata: caps.has_str("METADATA"),
         can_push: caps.has_str("XDELTAPUSH"),
+        is_chatmail: caps.has_str("XCHATMAIL"),
         server_id,
     };
     Ok(capabilities)

src/imap/session.rs

@@ -94,6 +94,11 @@ impl Session {
         self.capabilities.can_push
     }
 
+    // Returns true if IMAP server has `XCHATMAIL` capability.
+    pub fn is_chatmail(&self) -> bool {
+        self.capabilities.is_chatmail
+    }
+
     /// Returns the names of all folders on the IMAP server.
     pub async fn list_folders(&mut self) -> Result<Vec<async_imap::types::Name>> {
         let list = self.list(Some(""), Some("*")).await?.try_collect().await?;

src/scheduler.rs

@@ -466,6 +466,12 @@ pub async fn convert_folder_meaning(
 }
 
 async fn inbox_fetch_idle(ctx: &Context, imap: &mut Imap, mut session: Session) -> Result<Session> {
+    ctx.set_config_internal(
+        Config::IsChatmail,
+        crate::config::from_bool(session.is_chatmail()),
+    )
+    .await?;
+
     // Update quota no more than once a minute.
     let quota_needs_update = {
         let quota = ctx.quota.read().await;