* refactor: LocationProvider classes moved to src/helpers/sensors

* refactor:  Heltec_Wireless_Tracker* env moved to new variants/heltec_tracker dir

src/helpers/sensors/LocationProvider.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "Mesh.h"
+
+
+class LocationProvider {
+
+public:
+    virtual long getLatitude() = 0;
+    virtual long getLongitude() = 0;
+    virtual bool isValid() = 0;
+    virtual long getTimestamp() = 0;
+    virtual void reset();
+    virtual void begin();
+    virtual void stop();
+    virtual void loop();
+};

src/helpers/sensors/MicroNMEALocationProvider.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include "LocationProvider.h"
+#include <MicroNMEA.h>
+#include <RTClib.h>
+
+#ifndef GPS_EN
+#define GPS_EN (-1)
+#endif
+
+#ifndef GPS_RESET
+#define GPS_RESET (-1)
+#endif
+
+#ifndef GPS_RESET_FORCE
+#define GPS_RESET_FORCE LOW
+#endif
+
+class MicroNMEALocationProvider : public LocationProvider {
+    char _nmeaBuffer[100];
+    MicroNMEA nmea;
+    Stream* _gps_serial;
+    int _pin_reset;
+    int _pin_en;
+
+public :
+    MicroNMEALocationProvider(Stream& ser, int pin_reset = GPS_RESET, int pin_en = GPS_EN) :
+    _gps_serial(&ser), nmea(_nmeaBuffer, sizeof(_nmeaBuffer)), _pin_reset(pin_reset), _pin_en(pin_en) {
+        if (_pin_reset != -1) {
+            pinMode(_pin_reset, OUTPUT);
+            digitalWrite(_pin_reset, GPS_RESET_FORCE);
+        }
+        if (_pin_en != -1) {
+            pinMode(_pin_en, OUTPUT);
+            digitalWrite(_pin_en, LOW);
+        }
+    }
+
+    void begin() override {
+        if (_pin_reset != -1) {
+            digitalWrite(_pin_reset, !GPS_RESET_FORCE);
+        }
+        if (_pin_en != -1) {
+            digitalWrite(_pin_en, HIGH);
+        }
+    }
+
+    void reset() override {
+        if (_pin_reset != -1) {
+            digitalWrite(_pin_reset, GPS_RESET_FORCE);
+            delay(100);
+            digitalWrite(_pin_reset, !GPS_RESET_FORCE);
+        }
+    }
+
+    void stop() override {
+        if (_pin_en != -1) {
+            digitalWrite(_pin_en, LOW);
+        }        
+    }
+
+    long getLatitude() override { return nmea.getLatitude(); }
+    long getLongitude() override { return nmea.getLongitude(); }
+    bool isValid() override { return nmea.isValid(); }
+
+    long getTimestamp() override { 
+        DateTime dt(nmea.getYear(), nmea.getMonth(),nmea.getDay(),nmea.getHour(),nmea.getMinute(),nmea.getSecond());
+        return dt.unixtime();
+    } 
+
+    void loop() override {
+        while (_gps_serial->available()) {
+            char c = _gps_serial->read();
+            #ifdef GPS_NMEA_DEBUG
+            Serial.print(c);
+            #endif
+            nmea.process(c);
+        }
+    }
+};