// Define the pins for the GPS and GSM modules
#define RX1 3   // GPS RX
#define TX1 1   // GPS TX
#define RX2 16  // GSM RX
#define TX2 17  // GSM TX

void setup() {
  // Start serial communication
  Serial.begin(115200);  // Debugging via Serial (UART0)
  Serial1.begin(9600, SERIAL_8N1, RX1, TX1);  // GPS Serial (UART1)
  Serial2.begin(9600, SERIAL_8N1, RX2, TX2);  // GSM Serial (UART2)

  // Initialize the modules
  Serial.println("Initializing...");
}

void loop() {
  // Inject fake NMEA data
  String fakeNMEA = "$GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47";
  parseNMEA(fakeNMEA);

  // Simulate a delay
  delay(5000);  // Wait 5 seconds before the next iteration
}

void parseNMEA(String nmea) {
  // Example NMEA sentence: $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47
  // Split the string by commas
  int index = 0;
  String parts[15];
  
  while (nmea.length() > 0) {
    int commaIndex = nmea.indexOf(',');
    if (commaIndex == -1) {
      parts[index++] = nmea;
      break;
    } else {
      parts[index++] = nmea.substring(0, commaIndex);
      nmea = nmea.substring(commaIndex + 1);
    }
  }

  if (index >= 6) {
    // Parse latitude and longitude
    String latStr = parts[2];
    String latDir = parts[3];
    String lngStr = parts[4];
    String lngDir = parts[5];

    float latitude = convertToDecimalDegrees(latStr, latDir);
    float longitude = convertToDecimalDegrees(lngStr, lngDir);

    Serial.print("Latitude: ");
    Serial.println(latitude, 6);
    Serial.print("Longitude: ");
    Serial.println(longitude, 6);

    sendData(latitude, longitude);
  }
}

float convertToDecimalDegrees(String rawCoord, String direction) {
  float degrees = rawCoord.substring(0, 2).toFloat();
  float minutes = rawCoord.substring(2).toFloat();

  float decimalDegrees = degrees + (minutes / 60.0);
  if (direction == "S" || direction == "W") {
    decimalDegrees *= -1;
  }

  return decimalDegrees;
}

void sendData(float lat, float lng) {
  String lat_str = String(lat, 6);
  String lng_str = String(lng, 6);

  // Fake SIM800L setup using Serial2
  Serial2.println("AT");
  delay(1000);
  Serial2.println("AT+CPIN?"); // Check SIM card presence
  delay(1000);
  Serial2.println("AT+CREG?"); // Check network registration
  delay(1000);
  Serial2.println("AT+CGATT?"); // Check GPRS status
  delay(1000);
  Serial2.println("AT+CIPSHUT"); // Reset IP session
  delay(1000);
  Serial2.println("AT+CIPMUX=0"); // Single connection mode
  delay(1000);
  Serial2.println("AT+CSTT=\"your_apn\",\"\",\"\""); // Setup APN
  delay(1000);
  Serial2.println("AT+CIICR"); // Bring up wireless connection
  delay(3000);
  Serial2.println("AT+CIFSR"); // Get IP address
  delay(2000);
  Serial2.println("AT+CIPSTART=\"TCP\",\"your.server.com\",\"80\""); // Start connection to the server
  delay(5000);

  // Prepare HTTP POST data
  String httpRequest = "GET /track?lat=" + lat_str + "&lng=" + lng_str + " HTTP/1.1\r\nHost: your.server.com\r\n\r\n";

  Serial2.print("AT+CIPSEND=");
  Serial2.println(httpRequest.length());
  delay(100);
  Serial2.print(httpRequest);

  delay(1000);
  Serial2.println("AT+CIPCLOSE"); // Close the connection
  delay(1000);
}