li3: decode status flags, fix info-sensor expire_after, restart bluetooth after first failed scan

- status_text: decode the 24-bit "status" field into human-readable flag
  names (e.g. "Cell Temp Low, Low Voltage") instead of raw hex, using the
  bit table pulled from com.lithionics.bms's array/advanced resource (dumped
  with aapt -- the app's own StatusCodeTable class references stale/wrong
  resource IDs and can't be trusted for this). Applied to "status" only;
  last_fault_code is a lifetime latch that accumulates many bits over time
  and isn't meaningfully summarized the same way.

- Fixed the info sensors (total_consumed, firmware_version, serial_number,
  etc.) showing "Unavailable" in HA a minute after connecting: they were
  getting the same expire_after as the periodic telemetry sensors, but the
  $info line the come from is only sent once per BLE connection, so HA's
  expire timer always fired. These are retained-topic diagnostics meant to
  hold their last value indefinitely; expire_after now only applies to the
  periodic SENSORS group.

- STUCK_DISCOVERY_THRESHOLD 3 -> 1: restart bluetooth.service after the
  first failed scan instead of waiting for three, cutting reconnect time
  roughly in third. Still rate-limited via BLUETOOTH_RESTART_COOLDOWN_S.

Also removed the per-line "RAW ..." debug print (was flooding the journal).

All three changes verified live on host wan via journalctl/mosquitto_sub.

README.md

@@ -282,8 +282,8 @@ script's docstring for the full field layout.
   systemd restarts. This Pi's onboard Bluetooth adapter (Cypress/CYW43) occasionally
   wedges bluetoothd's discovery state after a run of failed connects to this specific
   device (`Discovering` stays `yes` forever, every subsequent connect fails with
-  `le-connection-abort-by-local`) — after 3 consecutive scan failures the daemon
+  `le-connection-abort-by-local`) — as soon as a scan fails the daemon restarts
-  restarts `bluetooth.service` itself to clear it, rate-limited to once per 5 min so it
+  `bluetooth.service` itself to clear it, rate-limited to once per 5 min so it
   doesn't repeatedly disrupt the AP's other BLE gear (motion sensors, IR remote).
 - This BLE module accepts only **one central connection at a time** — while
   `van-li3-battery` holds it, the Li3 phone app can't connect simultaneously.

li3/van-li3-battery

@@ -11,10 +11,11 @@
 # occasionally wedges its discovery state after a run of failed connection
 # attempts (Discovering stays "yes" forever, and every subsequent connect
 # fails with le-connection-abort-by-local) — observed happening from our own
-# repeated scan/connect cycling, not anything external. After several
+# repeated scan/connect cycling, not anything external. We restart
-# consecutive failures we restart bluetooth.service ourselves to clear that,
+# bluetooth.service ourselves as soon as a scan fails to clear that, rate-
-# rate-limited so we don't do it so often it disrupts the other BLE gear on
+# limited (BLUETOOTH_RESTART_COOLDOWN_S) so we don't do it so often it
-# this hub (motion sensors, IR remote, etc. also served by bluetoothd here).
+# disrupts the other BLE gear on this hub (motion sensors, IR remote, etc.
+# also served by bluetoothd here).
 #
 # Only exits (letting systemd Restart=always give us a fresh process) on
 # MQTT-level failure, which shouldn't happen in normal operation.
@@ -29,7 +30,7 @@ import paho.mqtt.client as mqtt
 from bleak import BleakClient, BleakScanner
 
 BLE_RETRY_DELAY_S = 8
-STUCK_DISCOVERY_THRESHOLD = 3       # consecutive scan failures before we intervene
+STUCK_DISCOVERY_THRESHOLD = 1       # consecutive scan failures before we intervene
 BLUETOOTH_RESTART_COOLDOWN_S = 300  # don't restart bluetooth.service more than this often
 
 config_path = sys.argv[1] if len(sys.argv) > 1 else "/etc/van-li3/config.json"
@@ -94,6 +95,37 @@ INFO_SENSORS = [
 
 info_topic = cfg.get("info_topic", f"van/{device_id}/info")
 
+# The "status" field (main Cs telemetry line, and identically-coded but
+# cumulative/latched "last_fault_code" from $info) is a 24-bit flag mask.
+# Bit meanings pulled from the app's own "advanced" string-array resource
+# (com.lithionics.bms base.apk, array/advanced -- dumped with aapt since the
+# app's Kotlin StatusCodeTable class references stale/wrong resource IDs and
+# can't be trusted). Index 0 = bit 23 (MSB) down to index 23 = bit 0 (LSB);
+# blank entries are unused bits. Applied to "status" only -- last_fault_code
+# is a lifetime latch (many bits accumulate over time) and isn't meaningfully
+# summarized the same way.
+STATUS_FLAGS = [
+    "", "BMS Temp High", "Overcurrent State", "Charge OFF", "Aux Input State",
+    "Cell Temp Low", "Cell Temp High", "AGSR State", "Temp Sensor Fault",
+    "CAN Charger Fault", "CAN Charger Present", "AC Power Present",
+    "Contactor Flutter", "Pre-Charge Fault", "Contactor Fault",
+    "Contactor State", "Power Off State", "Battery Protection", "Low Voltage",
+    "Reserve Range", "OptoLoop Open", "NeverDie Reserve", "Charge Detected",
+    "High Voltage",
+]
+
+
+def decode_status(hex_code):
+    try:
+        value = int(hex_code, 16)
+    except (ValueError, TypeError):
+        return hex_code
+    active = [
+        label for i, label in enumerate(STATUS_FLAGS)
+        if label and (value >> (23 - i)) & 1
+    ]
+    return ", ".join(active) if active else "OK"
+
 
 def parse_line(line):
     """Cs-series main telemetry line (no prefix character)."""
@@ -158,7 +190,7 @@ def parse_info_line(line):
         return None
 
 
-def _sensor_config(key, name, unit, device_class, precision, topic_state, device_info):
+def _sensor_config(key, name, unit, device_class, precision, topic_state, device_info, expire_after=None):
     numeric = precision is not None
     payload = {
         "name": name,
@@ -172,8 +204,9 @@ def _sensor_config(key, name, unit, device_class, precision, topic_state, device
             else f"{{{{ value_json.{key} }}}}"
         ),
         "device": device_info,
-        "expire_after": publish_interval_s * 4,
     }
+    if expire_after is not None:
+        payload["expire_after"] = expire_after
     if numeric:
         payload["suggested_display_precision"] = precision
         payload["state_class"] = "measurement"
@@ -189,7 +222,10 @@ def publish_discovery(mqc):
     }
     for key, name, unit, device_class, precision in SENSORS:
         topic = f"{discovery_prefix}/sensor/{device_id}/{key}/config"
-        payload = _sensor_config(key, name, unit, device_class, precision, state_topic, device_info)
+        payload = _sensor_config(
+            key, name, unit, device_class, precision, state_topic, device_info,
+            expire_after=publish_interval_s * 4,
+        )
         mqc.publish(topic, json.dumps(payload), retain=True)
 
     status_topic = f"{discovery_prefix}/sensor/{device_id}/status/config"
@@ -197,7 +233,7 @@ def publish_discovery(mqc):
         "name": "Status",
         "unique_id": f"{device_id}_status",
         "state_topic": state_topic,
-        "value_template": "{{ 'OK' if value_json.status == '000000' else value_json.status }}",
+        "value_template": "{{ value_json.status_text }}",
         "device": device_info,
         "expire_after": publish_interval_s * 4,
     }
@@ -223,8 +259,9 @@ def build_state_payload(cs_reading, trace_fields):
     # cell4_voltage=34013.63) — publish only the status in that case. Trace
     # ("&" line) fields come from a separate message and are published
     # regardless.
-    if cs_reading["status"] != "000000":
+    status = cs_reading["status"]
-        payload = {"status": cs_reading["status"]}
+    if status != "000000":
+        payload = {"status": status}
     else:
         payload = {
             "voltage": cs_reading["voltage"],
@@ -236,14 +273,15 @@ def build_state_payload(cs_reading, trace_fields):
             "soc": cs_reading["soc_pct"],
             "bms_temperature": cs_reading["bms_temp_f"],
             "battery_temperature": cs_reading["batt_temp_f"],
-            "status": cs_reading["status"],
+            "status": status,
         }
+    payload["status_text"] = decode_status(status)
     payload.update(trace_fields)
     return payload
 
 
 def restart_bluetooth_service():
-    print("too many consecutive scan failures; restarting bluetooth.service")
+    print("scan failed; restarting bluetooth.service")
     subprocess.run(["systemctl", "restart", "bluetooth.service"], check=False)
     time.sleep(3)
 
@@ -285,7 +323,6 @@ async def stream_from_device(dev, mqc):
             line = line.strip()
             if not line:
                 continue
-            print("RAW", line)
             if line.startswith("&"):
                 trace = parse_trace_line(line)
                 if trace: