Optimise start of LocationController to after Network is connected

Source/Meadow.Clima/Controllers/LocationController.cs

@@ -1,6 +1,8 @@
 using Meadow.Devices.Clima.Hardware;
 using Meadow.Peripherals.Sensors.Location.Gnss;
+using Meadow.Units;
 using System;
+using System.Threading;
 
 namespace Meadow.Devices.Clima.Controllers;
 
@@ -21,6 +23,8 @@ public class LocationController
     /// </summary>
     public event EventHandler<GnssPositionInfo>? PositionReceived = null;
 
+    private ManualResetEvent positionReceived = new ManualResetEvent(false);
+
     /// <summary>
     /// Initializes a new instance of the <see cref="LocationController"/> class.
     /// </summary>
@@ -31,21 +35,66 @@ public LocationController(IClimaHardware clima)
         {
             this.gnss = gnss;
             this.gnss.GnssDataReceived += OnGnssDataReceived;
-            this.gnss.StartUpdating();
         }
     }
 
+    /// <summary>
+    /// Gets the current geographic position as a <see cref="GeographicCoordinate"/>.
+    /// </summary>
+    /// <value>
+    /// The geographic position, including latitude, longitude, and altitude, if available.
+    /// </value>
+    /// <remarks>
+    /// This property is updated when valid GNSS data is received. It represents the last known position
+    /// and remains unchanged until new valid data is processed.
+    /// </remarks>
+    public GeographicCoordinate? Position { get; private set; } = default;
+
     private void OnGnssDataReceived(object sender, IGnssResult e)
     {
         if (e is GnssPositionInfo pi)
         {
             if (pi.IsValid && pi.Position != null)
             {
+                // remember our position
+                Position = pi.Position;
                 // we only need one position fix - weather stations don't move
                 Resolver.Log.InfoIf(LogData, $"GNSS Position: lat: [{pi.Position.Latitude}], long: [{pi.Position.Longitude}]");
+                positionReceived.Set();
                 PositionReceived?.Invoke(this, pi);
-                gnss?.StopUpdating();
+                StopUpdating();
             }
         }
     }
-}
+
+    /// <summary>
+    /// Starts the GNSS sensor to begin updating location data.
+    /// </summary>
+    /// <remarks>
+    /// This method invokes the <see cref="IGnssSensor.StartUpdating"/> method on the associated GNSS sensor,
+    /// if it is available, to start receiving GNSS data updates.
+    /// </remarks>
+    public void StartUpdating(bool forced = false)
+    {
+        // start updating if forced to find new data or we don;t have current location
+        if (forced || !positionReceived.WaitOne(0))
+        {
+            gnss?.StartUpdating();
+        };
+    }
+
+    /// <summary>
+    /// Stops the GNSS sensor from updating location data.
+    /// </summary>
+    /// <remarks>
+    /// This method halts the GNSS data updates by invoking the <see cref="IGnssSensor.StopUpdating"/> 
+    /// method on the associated GNSS sensor, if it is available.
+    /// </remarks>
+    public void StopUpdating()
+    {
+        // stop listening to data arriving from GNSS
+        gnss?.StopUpdating();
+
+        // TODO: can we tell GNSS sensor to stop calculating GPS location and stop sending data to reduce power consumption?
+    }
+}

Source/Meadow.Clima/MainController.cs

@@ -14,9 +14,9 @@
 /// </summary>
 public class MainController
 {
     private NotificationController notificationController;
     private SensorController sensorController;
     private PowerController powerController;
     private LocationController locationController;
     private NetworkController? networkController;
     private CloudController cloudController;
@@ -58,9 +58,9 @@
         powerController.SolarVoltageWarning += OnSolarVoltageWarning;
         powerController.BatteryVoltageWarning += OnBatteryVoltageWarning;
 
-        locationController = new LocationController(hardware);
 
-        locationController.PositionReceived += OnPositionReceived;
+
+
 
         if (networkAdapter == null)
         {
@@ -91,6 +91,9 @@
         Resolver.MeadowCloudService.ConnectionStateChanged += OnMeadowCloudServiceConnectionStateChanged;
         cloudController.LogAppStartup(hardware.RevisionString);
 
+        locationController = new LocationController(hardware);
+        locationController.PositionReceived += OnPositionReceived;
+
         Resolver.Device.PlatformOS.AfterWake += PlatformOS_AfterWake;
 
         if (!lowPowerMode)
@@ -113,6 +116,7 @@
         Resolver.Log.Info($"Start Updating");
         sensorController.StartUpdating(sensorController.UpdateInterval);
         powerController.StartUpdating(powerController.UpdateInterval);
+        locationController.StartUpdating();
     }
 
     /// <summary>
@@ -123,6 +127,7 @@
         Resolver.Log.Info($"Stop Updating");
         sensorController.StopUpdating();
         powerController.StopUpdating();
+        locationController.StopUpdating();
         sleepSimulationTimer.Change(-1, -1); // stop timer
     }
 
@@ -206,7 +211,15 @@
         {
             case CloudConnectionState.Connected:
                 notificationController.SetSystemStatus(NotificationController.SystemStatus.Connected);
+
+                locationController.StartUpdating();
                 break;
+
+            case CloudConnectionState.Disconnected:
+            case CloudConnectionState.Unknown:
+                locationController.StopUpdating();
+                break;
+
             default:
                 notificationController.SetSystemStatus(NotificationController.SystemStatus.ConnectingToCloud);
                 break;
@@ -312,4 +325,4 @@
             Resolver.Log.Info(report);
         }
     }
-}
+}