#include <SPI.h>
#include <LoRa.h>
#include <TinyGPS++.h>
#include <SoftwareSerial.h>

#include "pb_common.h"
#include "pb.h"
#include "pb_encode.h"

#include "message.pb.h"

unsigned long previousMillis = 0;
const long interval = 5000;
float lat = 0;
float lng = 0;

TinyGPSPlus gps;

SoftwareSerial ss(6, 7);

void setup() {
  Serial.begin(9600);
  ss.begin(9600);
  
  while (!Serial);

  Serial.println("LoRa Transceiver");

  if (!LoRa.begin(915E6)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }
   LoRa.setSpreadingFactor(7);
}

void loop() {

  int packetSize = LoRa.parsePacket();
  if (packetSize) {
    Serial.print("Received Packet: ");
    while (LoRa.available()) {
      Serial.print((char) LoRa.read());  
    }
    Serial.println();
  }

  unsigned long currentMillis = millis();
  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
    
    // Gather GPS data
    if (gps.encode(ss.read()) && gps.location.isValid()) {
      Serial.println("Valid GPS");
      lat = gps.location.lat();
      lng = gps.location.lng(); 
    } else {
      lat = 0;
      lng = 0;  
    }

    // Encode as protobuf packet
    if (lat && lng) {
      uint8_t buffer[50] = {0};
      Fenceless_CollarResponse m = Fenceless_CollarResponse_init_zero;
      pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
      m.loc.x = lat;
      m.loc.y = lng;

      int status = pb_encode(&stream, Fenceless_CollarResponse_fields, &m);
      
      if (!status) {
        Serial.println("Failed to encode");  
      } else {
        Serial.print("Status: ");
        Serial.println(status);  
      }

      Serial.print("Sending packet Lat / Long: ");
      Serial.print(lat);
      Serial.println(lng);

      // send packet
  
      LoRa.beginPacket();
      LoRa.print((char *) buffer);
      LoRa.endPacket();
      
    } else {
      Serial.println("GPS has not yet initialized");  
    }
  }
}