offline queue bump, lossless message sync via ble

zephcore/Kconfig

@@ -120,9 +120,10 @@ config ZEPHCORE_MAX_CHANNELS
 
 config ZEPHCORE_OFFLINE_QUEUE_SIZE
 	int "Offline message queue size"
-	default 16
+	default 256
 	help
 	  Size of the offline message queue for incoming messages.
+	  Arduino MeshCore uses 256 for both T1000-E and Wio Tracker.
 
 config ZEPHCORE_ACK_TABLE_SIZE
 	int "ACK tracking table size"

zephcore/adapters/ble/ZephyrBLE.cpp

@@ -121,6 +121,7 @@ static bool dle_requested;
 /* Advertising state */
 static bool adv_switching = false;
 static bool adv_is_slow = false;
+static bool adv_post_disconnect = false;  /* skip fast advert after disconnect */
 
 /* Runtime BLE passkey */
 static uint32_t ble_passkey = CONFIG_ZEPHCORE_BLE_PASSKEY;
@@ -340,6 +341,10 @@ static void disconnected(struct bt_conn *conn, uint8_t reason)
 	k_work_cancel_delayable(&tx_drain_work);
 	k_work_cancel_delayable(&overflow_retry_work);
 
+	/* Skip fast advertising on reconnect — go straight to slow.
+	 * Prevents tight reconnect flapping loops on flaky links. */
+	adv_post_disconnect = true;
+
 	/* Notify main of BLE disconnection */
 	if (ble_cbs && ble_cbs->on_disconnected) {
 		ble_cbs->on_disconnected();
@@ -354,6 +359,16 @@ static void recycled(void)
 			adv_switching, adv_is_slow);
 		return;
 	}
+
+	if (adv_post_disconnect) {
+		/* After disconnect, skip fast advertising — go straight to slow.
+		 * Prevents rapid reconnect flapping on flaky BLE links. */
+		adv_post_disconnect = false;
+		LOG_INF("post-disconnect: starting slow advertising directly");
+		adv_slow_work_fn(NULL);
+		return;
+	}
+
 	LOG_DBG("restart advertising");
 	start_adv();
 }

zephcore/app/CompanionMesh.cpp

@@ -158,6 +158,7 @@ CompanionMesh::CompanionMesh(mesh::Radio &radio, mesh::MillisecondClock &ms, mes
 	_offline_queue_head = 0;
 	_offline_queue_tail = 0;
 	_offline_queue_count = 0;
+	_sync_pending = false;
 	memset(_ack_table, 0, sizeof(_ack_table));
 	_ack_next_overwrite = 0;
 	memset(_advert_paths, 0, sizeof(_advert_paths));
@@ -392,6 +393,22 @@ bool CompanionMesh::dequeueOfflineMessage(uint8_t *dest, size_t &len)
 	return true;
 }
 
+bool CompanionMesh::peekOfflineMessage(uint8_t *dest, size_t &len)
+{
+	if (_offline_queue_count == 0) return false;
+	QueuedFrame *f = &_offline_queue[_offline_queue_head];
+	len = f->len;
+	memcpy(dest, f->buf, len);
+	return true;  /* head NOT advanced — message stays in queue */
+}
+
+void CompanionMesh::confirmOfflineMessage()
+{
+	if (_offline_queue_count == 0) return;
+	_offline_queue_head = (_offline_queue_head + 1) % OFFLINE_QUEUE_SIZE;
+	_offline_queue_count--;
+}
+
 void CompanionMesh::resetContactIterator()
 {
 	if (_contact_iter_active) {
@@ -1677,12 +1694,21 @@ bool CompanionMesh::handleProtocolFrame(const uint8_t *data, size_t len)
 	}
 
 	case CMD_SYNC_NEXT_MESSAGE: {
-		LOG_INF("CMD_SYNC_NEXT_MESSAGE: queue_count=%d", _offline_queue_count);
+		LOG_INF("CMD_SYNC_NEXT_MESSAGE: queue_count=%d pending=%d",
+			_offline_queue_count, _sync_pending);
+
+		/* Phone asking for next = implicit ACK for the previously-peeked message */
+		if (_sync_pending) {
+			confirmOfflineMessage();
+			_sync_pending = false;
+		}
+
 		uint8_t buf[MAX_FRAME_SIZE];
 		size_t msg_len;
-		if (dequeueOfflineMessage(buf, msg_len)) {
-			LOG_INF("CMD_SYNC_NEXT_MESSAGE: dequeued msg_len=%u type=0x%02x", (unsigned)msg_len, buf[0]);
+		if (peekOfflineMessage(buf, msg_len)) {
+			LOG_INF("CMD_SYNC_NEXT_MESSAGE: peeked msg_len=%u type=0x%02x", (unsigned)msg_len, buf[0]);
 			writeFrame(buf, msg_len);
+			_sync_pending = true;  /* will be confirmed on next request or lost on disconnect */
 		} else {
 			LOG_INF("CMD_SYNC_NEXT_MESSAGE: queue empty, sending NO_MORE_MSGS");
 			uint8_t rsp[] = { PACKET_NO_MORE_MSGS };

zephcore/app/CompanionMesh.h

@@ -162,9 +162,22 @@ public:
 
 	/**
 	 * Reset contact iterator (call when new command received).
+	 * Sends PACKET_CONTACT_END if iteration was in progress.
 	 */
 	void resetContactIterator();
 
+	/**
+	 * Cancel contact iteration silently (no frame sent).
+	 * Call on BLE disconnect — there's nobody to send CONTACT_END to.
+	 */
+	void cancelContactIterator() { _contact_iter_active = false; }
+
+	/**
+	 * Cancel pending message sync. Un-ACKed message stays in queue.
+	 * Call on BLE disconnect so the message is re-sent on reconnect.
+	 */
+	void cancelSyncPending() { _sync_pending = false; }
+
 	/**
 	 * Get BLE device name for advertising.
 	 */
@@ -270,6 +283,7 @@ private:
 	int _offline_queue_head;
 	int _offline_queue_tail;
 	int _offline_queue_count;
+	bool _sync_pending;  /* true = last peeked message not yet ACKed by phone */
 
 	/* ACK tracking table */
 	struct AckEntry {
@@ -328,6 +342,8 @@ private:
 
 	void queueOfflineMessage(const uint8_t *data, size_t len);
 	bool dequeueOfflineMessage(uint8_t *dest, size_t &len);
+	bool peekOfflineMessage(uint8_t *dest, size_t &len);
+	void confirmOfflineMessage();
 
 	void queueContactMessage(const ContactInfo &contact, mesh::Packet *pkt,
 		uint8_t txt_type, uint32_t sender_timestamp, const uint8_t *extra, int extra_len, const char *text);

zephcore/src/main_companion.cpp

@@ -141,11 +141,21 @@ static void ble_on_connected(void)
 	ui_notify(UI_EVENT_BLE_CONNECTED);
 }
 
-/* BLE disconnected callback — notify UI */
+/* BLE disconnected callback — clean up state and notify UI */
 static void ble_on_disconnected(void)
 {
 #if IS_ENABLED(CONFIG_LOG)
 	zephcore_usb_companion_reset_rx();
+#endif
+#ifdef ZEPHCORE_LORA
+	/* Silently cancel any in-progress contact iteration.
+	 * Without this, reconnect triggers resetContactIterator() which sends
+	 * a stale PACKET_CONTACT_END to the NEW connection, confusing the
+	 * phone's sync state machine. */
+	companion_mesh_ptr->cancelContactIterator();
+	/* Reset message sync — un-ACKed peeked message stays in queue
+	 * and will be re-sent on next CMD_SYNC_NEXT_MESSAGE. */
+	companion_mesh_ptr->cancelSyncPending();
 #endif
 	ui_notify(UI_EVENT_BLE_DISCONNECTED);
 }
@@ -205,8 +215,10 @@ static void rx_process_work_fn(struct k_work *work)
 	/* Process all queued frames */
 	while (k_msgq_get(zephcore_ble_get_recv_queue(), &f, K_NO_WAIT) == 0) {
 #ifdef ZEPHCORE_LORA
-		/* Reset contact iterator when new command received */
-		companion_mesh_ptr->resetContactIterator();
+		/* handleProtocolFrame() resets the contact iterator internally
+		 * (line 1229) for any non-CMD_GET_CONTACTS command — no need
+		 * to call resetContactIterator() here.  Doing so sent a stale
+		 * PACKET_CONTACT_END before the command was even processed. */
 		if (!companion_mesh_ptr->handleProtocolFrame(f.buf, f.len)) {
 			LOG_DBG("rx_process: unknown cmd 0x%02x len=%u", f.buf[0], (unsigned)f.len);
 			uint8_t err_rsp[] = { 0x01, 0x01 };  /* PACKET_ERROR, ERR_UNSUPPORTED */