update MeshService to use Position struct

src/mesh/MeshService.cpp

@@ -213,27 +213,32 @@ int MeshService::onGPSChanged(const meshtastic::GPSStatus *newStatus)
 {
     // Update our local node info with our position (even if we don't decide to update anyone else)
     NodeInfo *node = refreshMyNodeInfo();
-    Position pos = node->position;
+    Position pos = Position_init_default;
 
     if (newStatus->getHasLock()) {
-        if (gps->altitude != 0)
-            pos.altitude = gps->altitude;
-        pos.latitude_i = gps->latitude;
-        pos.longitude_i = gps->longitude;
+        // load data from GPS object, will add timestamp + battery further down
+        pos = gps->p;
     } else {
         // The GPS has lost lock, if we are fixed position we should just keep using
         // the old position
+#if GPS_EXTRAVERBOSE
+        DEBUG_MSG("onGPSchanged() - lost validLocation\n");
+#endif
         if (radioConfig.preferences.fixed_position) {
             DEBUG_MSG("WARNING: Using fixed position\n");
-        } else {
-            // throw away old position
-            pos.latitude_i = 0;
-            pos.longitude_i = 0;
-            pos.altitude = 0;
+            pos = node->position;
         }
     }
 
-    DEBUG_MSG("got gps notify time=%u, lat=%d, bat=%d\n", pos.time, pos.latitude_i, pos.battery_level);
+    // Finally add a fresh timestamp and battery level reading
+    // I KNOW this is redundant with refreshMyNodeInfo() above, but these are
+    //   inexpensive nonblocking calls and can be refactored in due course
+    pos.time = getValidTime(RTCQualityGPS);
+    pos.battery_level = powerStatus->getBatteryChargePercent();
+
+    // In debug logs, identify position by @timestamp:stage (stage 4 = nodeDB)
+    DEBUG_MSG("onGPSChanged() pos@%x:4, time=%u, lat=%d, bat=%d\n", 
+                pos.pos_timestamp, pos.time, pos.latitude_i, pos.battery_level);
 
     // Update our current position in the local DB
     nodeDB.updatePosition(nodeDB.getNodeNum(), pos, RX_SRC_LOCAL);