#include <SoftwareSerial.h>
//#include <TinyGPS++.h>

// Define GSM and GPS pins
#define GSM_TX_PIN 4
#define GSM_RX_PIN 2
#define GSM_RST_PIN 0

// #define GPS_TX_PIN 16
// #define GPS_RX_PIN 17

// Define button pin
#define BUTTON_PIN 18

SoftwareSerial gsmSerial(GSM_TX_PIN, GSM_RX_PIN); // RX, TX for GSM
//SoftwareSerial gpsSerial(GPS_TX_PIN, GPS_RX_PIN); // RX, TX for GPS

//TinyGPSPlus gps;

void updateSerial() {
  while (gsmSerial.available()) {
    Serial.write(gsmSerial.read());
  }
  while (Serial.available()) {
    gsmSerial.write(Serial.read());
  }
}

void sendSMS(const String& message) {
  gsmSerial.println("AT+CMGF=1"); // Set GSM module to text mode
  delay(1000);
  gsmSerial.println("AT+CMGS=\"+919820443686\""); // Replace with the recipient's phone number
  delay(1000);
  gsmSerial.print(message);
  delay(100);
  gsmSerial.write(26); // ASCII code for CTRL+Z to send the message
  delay(1000);
}

void setup() {
  Serial.begin(115200);
  gsmSerial.begin(115200); // Initialize communication with SIM800L
  //gpsSerial.begin(9600); // Initialize communication with GPS module

  pinMode(BUTTON_PIN, INPUT_PULLUP); // Initialize button pin with internal pull-up resistor

  Serial.println("Initializing");

  gsmSerial.println("AT"); // Check if SIM800L is responding
  updateSerial();

  delay(1000);

  Serial.println("Ready to send SMS when button is pressed.");
}

void loop() {
  if (digitalRead(BUTTON_PIN) == LOW) {
    Serial.println("Button pressed!");

    String message = "HELP! My current location is:\n";

    // // Get GPS data
    // while (gpsSerial.available() > 0) {
    //   gps.encode(gpsSerial.read());
    //   if (gps.location.isUpdated()) {
    //     message += "Latitude: " + String(gps.location.lat(), 6) + "\n";
    //     message += "Longitude: " + String(gps.location.lng(), 6) + "\n";
    //     break;
    //   }
    // }

    // // If no GPS data, indicate that location is unavailable
    // if (!gps.location.isValid()) {
    //   message += "GPS location not available.";
    // }

    // Send SMS with help message and location
    sendSMS(message);
    Serial.println("SMS sent: " + message);
    Serial.println("Message sucessfully sent to +91 9820443686 " );

    // Debounce delay to prevent multiple triggers from a single press
    delay(2000);
  }

  updateSerial(); // To keep the serial communication updated
}