Improve scan terminal freshness and AMSC overlay consistency

web/services/canonical_engine.py

@@ -185,7 +185,18 @@ def build_realtime_event_from_canonical(canonical: dict[str, Any]) -> Optional[d
         text = str(canonical.get(key) or "").strip()
         if text:
             payload[key] = text
-    for key in ("freshness_sec", "confidence"):
+    for key in (
+        "freshness_sec",
+        "confidence",
+        "max_so_far",
+        "signed_gap",
+        "gap_to_target",
+        "touch_distance",
+        "current_reference",
+        "edge",
+        "edge_percent",
+        "deb_prediction",
+    ):
         value_meta = canonical.get(key)
         if value_meta is not None and value_meta != "":
             payload[key] = value_meta

web/services/canonical_temperature.py

@@ -28,6 +28,14 @@ def _to_int(value: Any) -> Optional[int]:
         return None
 
 
+def _first_float(*values: Any) -> Optional[float]:
+    for value in values:
+        number = _to_float(value)
+        if number is not None:
+            return number
+    return None
+
+
 def _now_iso() -> str:
     return datetime.now(timezone.utc).isoformat()
 
@@ -127,6 +135,7 @@ def build_canonical_temperature(
     canonical = {
         "city": str(city or payload.get("name") or payload.get("city") or "").strip().lower(),
         "value": round(value, 2),
+        "max_so_far": _first_float(current.get("max_so_far"), current.get("max_temp_so_far")),
         "temp_symbol": str(payload.get("temp_symbol") or "°C"),
         "source": source,
         "source_label": source_label,
@@ -142,6 +151,10 @@ def build_canonical_temperature(
     }
     age_text = f" updated {freshness_sec}s ago" if freshness_sec is not None else ""
     canonical["explanation"] = f"{source_label or source or 'Source'}{age_text}."
+    deb = payload.get("deb") if isinstance(payload.get("deb"), dict) else {}
+    deb_prediction = _to_float(deb.get("prediction"))
+    if deb_prediction is not None:
+        canonical["deb_prediction"] = deb_prediction
     return canonical
 
 
@@ -190,6 +203,7 @@ def build_city_weather_from_canonical(city: str, canonical: Dict[str, Any]) -> O
     }
     current = {
         "temp": value,
+        "max_so_far": _first_float(canonical.get("max_so_far"), value),
         "source_code": source,
         "settlement_source": source,
         "settlement_source_label": source_label,
@@ -201,6 +215,7 @@ def build_city_weather_from_canonical(city: str, canonical: Dict[str, Any]) -> O
     }
     airport_primary = {
         "temp": value,
+        "max_so_far": _first_float(canonical.get("max_so_far"), value),
         "source_code": source,
         "source_label": source_label,
         "obs_time": observed_at or observed_at_local,

web/services/latest_observation_overlay.py

@@ -45,12 +45,19 @@ def _payload_latest_epoch(payload: dict[str, Any], keys: tuple[str, ...]) -> Opt
 def _block_epoch(block: Any) -> Optional[int]:
     if not isinstance(block, dict):
         return None
-    return _payload_latest_epoch(
+    canonical_epoch = _payload_latest_epoch(
         block,
         (
             "observed_at",
             "observation_time",
             "obs_time",
+        ),
+    )
+    if canonical_epoch is not None:
+        return canonical_epoch
+    return _payload_latest_epoch(
+        block,
+        (
             "observed_at_local",
             "observation_time_local",
         ),

web/services/scan_api.py

@@ -23,6 +23,17 @@ def _supports_timing_recorder(func: Any) -> bool:
     )
 
 
+def _supports_keyword(func: Any, name: str) -> bool:
+    try:
+        params = signature(func).parameters.values()
+    except (TypeError, ValueError):
+        return True
+    return any(
+        param.name == name or param.kind == Parameter.VAR_KEYWORD
+        for param in params
+    )
+
+
 async def get_scan_terminal_payload(
     request: Request,
     *,
@@ -36,6 +47,8 @@ async def get_scan_terminal_payload(
     time_range: str = "today",
     limit: int = 25,
     force_refresh: bool = False,
+    diff: bool = False,
+    since_snapshot_id: str | None = None,
     region: str = "",
     timezone_offset_seconds: int | None = None,
 ) -> Dict[str, Any]:
@@ -67,6 +80,10 @@ async def get_scan_terminal_payload(
         async def build_payload():
             builder = legacy_routes.build_scan_terminal_payload
             kwargs: Dict[str, Any] = {"force_refresh": force_refresh}
+            if _supports_keyword(builder, "diff"):
+                kwargs["diff"] = diff
+            if _supports_keyword(builder, "since_snapshot_id"):
+                kwargs["since_snapshot_id"] = since_snapshot_id
             if _supports_timing_recorder(builder):
                 kwargs["timing_recorder"] = timer
             return await run_in_threadpool(builder, filters, **kwargs)