feat: add realtime GNSS monitor with telemetry websocket

backend/app/mqtt/repository.py

@@ -77,6 +77,74 @@ def mark_failed(
     session.add(row)
 
 
+def _build_satellite_signal_summary(
+    *,
+    gsv_satellites: list[dict[str, Any]],
+    satellites_in_view: int | None,
+    used_satellite_ids: set[str],
+) -> dict[str, Any]:
+    deduped: dict[tuple[str, str], dict[str, Any]] = {}
+    for satellite in gsv_satellites:
+        constellation = str(satellite.get("constellation", "Unknown"))
+        satellite_id = str(satellite.get("satellite_id", "")).strip()
+        if not satellite_id:
+            continue
+        key = (constellation, satellite_id)
+        existing = deduped.get(key)
+        if existing is None:
+            deduped[key] = satellite
+            continue
+
+        incoming_snr = satellite.get("snr_dbhz")
+        existing_snr = existing.get("snr_dbhz")
+        if isinstance(incoming_snr, int) and (
+            not isinstance(existing_snr, int) or incoming_snr > existing_snr
+        ):
+            deduped[key] = satellite
+
+    satellites = list(deduped.values())
+    satellites.sort(
+        key=lambda sat: (str(sat["constellation"]), str(sat["satellite_id"]))
+    )
+
+    snr_values: list[int] = []
+    cn0_values: list[int] = []
+    constellation_summary: dict[str, dict[str, int]] = {}
+
+    for satellite in gsv_satellites:
+        cn0_value = satellite.get("snr_dbhz")
+        if isinstance(cn0_value, int):
+            cn0_values.append(cn0_value)
+
+    for satellite in satellites:
+        constellation = str(satellite["constellation"])
+        sat_id = str(satellite["satellite_id"])
+        used_in_navigation = sat_id in used_satellite_ids
+        satellite["used_in_navigation"] = used_in_navigation
+
+        constellation_item = constellation_summary.setdefault(
+            constellation,
+            {"count": 0, "with_signal": 0, "used_in_navigation": 0},
+        )
+        constellation_item["count"] += 1
+        if used_in_navigation:
+            constellation_item["used_in_navigation"] += 1
+
+        snr_dbhz = satellite.get("snr_dbhz")
+        if isinstance(snr_dbhz, int):
+            snr_values.append(snr_dbhz)
+            constellation_item["with_signal"] += 1
+
+    return {
+        "satellites_in_view": satellites_in_view or len(satellites),
+        "snr_values": snr_values,
+        "cn0_values": cn0_values,
+        "used_satellite_ids": sorted(used_satellite_ids),
+        "constellations": constellation_summary,
+        "satellites": satellites,
+    }
+
+
 def update_device_state_from_events(
     *,
     session: Session,
@@ -96,6 +164,10 @@ def update_device_state_from_events(
     if state is None:
         state = TerminalDeviceState(device_id=row.device_id)
 
+    gsv_satellites: list[dict[str, Any]] = []
+    satellites_in_view: int | None = None
+    used_satellite_ids: set[str] = set()
+
     for event in events:
         payload = event.get("payload", {})
         event_type = str(event.get("event_type", "unknown"))
@@ -114,16 +186,52 @@ def update_device_state_from_events(
             if payload.get("lon") is not None:
                 state.lon = payload.get("lon")
             status = payload.get("status")
-            if status is not None:
+            if status is not None and state.fix_status is None:
                 state.fix_status = str(status)
         elif event_type == "nmea_gsv":
-            state.satellite_signal_summary = {
-                "snr_values": payload.get("snr_values", []),
-                "satellites_in_view": payload.get("satellites_in_view"),
-            }
+            payload_satellites = payload.get("satellites", [])
+            if isinstance(payload_satellites, list):
+                for sat in payload_satellites:
+                    if not isinstance(sat, dict):
+                        continue
+                    gsv_satellites.append(
+                        {
+                            "satellite_id": str(sat.get("satellite_id", "")),
+                            "elevation_deg": sat.get("elevation_deg"),
+                            "azimuth_deg": sat.get("azimuth_deg"),
+                            "snr_dbhz": sat.get("snr_dbhz"),
+                            "constellation": payload.get("constellation", "Unknown"),
+                        }
+                    )
+            satellites_count = payload.get("satellites_in_view")
+            if isinstance(satellites_count, int):
+                satellites_in_view = max(satellites_in_view or 0, satellites_count)
+        elif event_type == "nmea_gsa":
+            for satellite_id in payload.get("used_satellite_ids", []):
+                if satellite_id is None:
+                    continue
+                used_satellite_ids.add(str(satellite_id))
         elif event_type == "rtcm_summary":
             state.rtcm_type_summary = payload.get("rtcm_types", {})
 
+    if gsv_satellites:
+        state.satellite_signal_summary = _build_satellite_signal_summary(
+            gsv_satellites=gsv_satellites,
+            satellites_in_view=satellites_in_view,
+            used_satellite_ids=used_satellite_ids,
+        )
+    elif used_satellite_ids and state.satellite_signal_summary:
+        current_summary = dict(state.satellite_signal_summary)
+        current_summary["used_satellite_ids"] = sorted(used_satellite_ids)
+        satellites = current_summary.get("satellites", [])
+        if isinstance(satellites, list):
+            for satellite in satellites:
+                if not isinstance(satellite, dict):
+                    continue
+                sat_id = str(satellite.get("satellite_id", ""))
+                satellite["used_in_navigation"] = sat_id in used_satellite_ids
+        state.satellite_signal_summary = current_summary
+
     state.last_event_time = row.received_at
     state.updated_at = get_datetime_utc()
     session.add(state)