Add local settings management

Add cellular-first ntfy delivery with WiFi fallback and safe SIM868 HTTP header framing.

Co-authored-by: Copilot <[email protected]>

modules/app_alerts.py

@@ -6,7 +6,15 @@ from urllib.parse import urlparse
 
 import requests
 
-from modules import app_dash, app_gps, app_health, app_obd, app_sql, app_video
+from modules import (
+    app_cellular,
+    app_dash,
+    app_gps,
+    app_health,
+    app_obd,
+    app_sql,
+    app_video,
+)
 
 
 CHECK_INTERVAL = 60
@@ -94,9 +102,29 @@ def send_ntfy(url, token, title, message, priority="default", tags=None):
         headers["Tags"] = ",".join(tags)
     if token:
         headers["Authorization"] = f"Bearer {token}"
+    body = message.encode("utf-8")
+    if app_cellular.is_configured():
+        cellular_failure = None
+        try:
+            status_code, _response_body = app_cellular.http_post(
+                url,
+                body,
+                headers,
+                content_type="text/plain; charset=utf-8",
+            )
+            if 200 <= status_code < 300:
+                return
+            cellular_failure = f"HTTP {status_code}"
+        except app_cellular.CellularError:
+            cellular_failure = "modem error"
+        print(
+            f"Cellular notification failed ({cellular_failure}); "
+            "trying WiFi/Ethernet."
+        )
+
     response = requests.post(
         url,
-        data=message.encode("utf-8"),
+        data=body,
         headers=headers,
         timeout=5,
     )
@@ -104,6 +132,8 @@ def send_ntfy(url, token, title, message, priority="default", tags=None):
 
 
 def _transport_error(error):
+    if isinstance(error, app_cellular.CellularError):
+        return "Cellular notification failed"
     if isinstance(error, requests.Timeout):
         return "Notification request timed out"
     if isinstance(error, requests.HTTPError):
@@ -398,7 +428,10 @@ def process_conditions(conditions, config, now=None, sender=send_ntfy):
                         condition["priority"],
                         condition["tags"],
                     )
-                except requests.RequestException as error:
+                except (
+                    requests.RequestException,
+                    app_cellular.CellularError,
+                ) as error:
                     state["last_error"] = _transport_error(error)
                 else:
                     state["last_sent_at"] = now
@@ -423,7 +456,10 @@ def process_conditions(conditions, config, now=None, sender=send_ntfy):
                         "default",
                         ["white_check_mark"],
                     )
-                except requests.RequestException as error:
+                except (
+                    requests.RequestException,
+                    app_cellular.CellularError,
+                ) as error:
                     state["last_error"] = _transport_error(error)
                 else:
                     state["recovery_pending"] = False
@@ -455,6 +491,7 @@ def _loop():
             RuntimeError,
             sqlite3.Error,
             requests.RequestException,
+            app_cellular.CellularError,
         ) as error:
             _last_run_error = str(error)
             print("Alert check failed:", error)