collection: add update_flags() method

On NewFlags events, the threads in Collection were not being updated, so
if an envelope's seen status was toggled the thread's unseen count was
  not updated, and thus not reflected in the UI even though the
  envelope's new flags event was registered properly.

1 files changed, 37 insertions, 0 deletions

diff --git a/melib/src/collection.rs b/melib/src/collection.rs
index a677c5de..159626ac 100644
--- a/melib/src/collection.rs
+++ b/melib/src/collection.rs
@@ -351,6 +351,43 @@ impl Collection {
         }
     }
 
+    pub fn update_flags(&mut self, env_hash: EnvelopeHash, mailbox_hash: MailboxHash) {
+        if self
+            .sent_mailbox
+            .map(|f| f == mailbox_hash)
+            .unwrap_or(false)
+        {
+            for (_, t) in self.threads.iter_mut() {
+                t.update_envelope(&self.envelopes, env_hash, env_hash)
+                    .unwrap_or(());
+            }
+        }
+        {
+            if self
+                .threads
+                .entry(mailbox_hash)
+                .or_default()
+                .update_envelope(&self.envelopes, env_hash, env_hash)
+                .is_ok()
+            {
+                return;
+            }
+        }
+        /* envelope is not in threads, so insert it */
+        self.threads
+            .entry(mailbox_hash)
+            .or_default()
+            .insert(&mut self.envelopes, env_hash);
+        for (h, t) in self.threads.iter_mut() {
+            if *h == mailbox_hash {
+                continue;
+            }
+            t.update_envelope(&self.envelopes, env_hash, env_hash)
+                .ok()
+                .take();
+        }
+    }
+
     pub fn insert(&mut self, envelope: Envelope, mailbox_hash: MailboxHash) -> bool {
         let hash = envelope.hash();
         if self.message_ids.contains_key(envelope.message_id().raw()) {