introduce two new events

src/events.rs

@@ -307,4 +307,12 @@ pub enum EventType {
     WebxdcInstanceDeleted {
         msg_id: MsgId,
     },
+
+    WebxdcBusyUpdating {
+        msg_id: MsgId,
+    },
+
+    WebxdcUpToDate {
+        msg_id: MsgId,
+    },
 }

src/scheduler.rs

@@ -332,7 +332,7 @@ async fn smtp_loop(ctx: Context, started: Sender<()>, smtp_handlers: SmtpConnect
                 if !duration_until_can_send.is_zero() {
                     info!(
                         ctx,
-                        "smtp got rate limited, waiting for {} until can send again",
+                        "smtp got rate limited, delaying next try by {}",
                         duration_to_str(duration_until_can_send)
                     );
                     tokio::time::timeout(duration_until_can_send, async {

src/smtp.rs

@@ -22,6 +22,7 @@ use crate::mimefactory::MimeFactory;
 use crate::oauth2::get_oauth2_access_token;
 use crate::provider::Socket;
 use crate::sql;
+use crate::webxdc::get_busy_webxdc_instances;
 use crate::{context::Context, scheduler::connectivity::ConnectivityStore};
 
 /// SMTP write and read timeout in seconds.
@@ -499,7 +500,15 @@ async fn send_mdns(context: &Context, connection: &mut Smtp) -> Result<()> {
 pub(crate) async fn send_smtp_messages(context: &Context, connection: &mut Smtp) -> Result<()> {
     let ratelimited = if context.ratelimit.read().await.can_send() {
         // add status updates and sync messages to end of sending queue
+
+        let update_needed = get_busy_webxdc_instances();
         context.flush_status_updates().await?;
+        let update_needed_after_sending = get_busy_webxdc_instances();
+    
+        for msg_id in update_needed.difference(&update_needed_after_sending) {
+            context.emit_event(EventType::WebxdcUpToDate { msg_id: *msg_id })
+        }
+
         context.send_sync_msg().await?;
         false
     } else {

src/webxdc.rs

@@ -1,5 +1,6 @@
 //! # Handle webxdc messages.
 
+use std::collections::HashSet;
 use std::convert::TryFrom;
 use std::path::Path;
 
@@ -377,6 +378,10 @@ impl Context {
             )
             .await?;
 
+        self.emit_event(EventType::WebxdcBusyUpdating {
+            msg_id: instance.id,
+        });
+
         if send_now {
             self.sql.insert(
                 "INSERT INTO smtp_status_updates (msg_id, first_serial, last_serial, descr) VALUES(?, ?, ?, ?)
@@ -390,7 +395,6 @@ impl Context {
     }
 
     /// Pops one record of queued webxdc status updates.
-    /// This function exists to make the sqlite statement testable.
     async fn pop_smtp_status_update(
         &self,
     ) -> Result<Option<(MsgId, StatusUpdateSerial, StatusUpdateSerial, String)>> {
@@ -744,6 +748,12 @@ impl Message {
     }
 }
 
+/// Returns a hashset of all webxdc instaces which still have updates to send
+pub(crate) fn get_busy_webxdc_instances() -> HashSet<MsgId> {
+    // TODO: add sql statement to find that out
+    unimplemented!()
+}
+
 #[cfg(test)]
 mod tests {
     use crate::chat::{