#include <SoftwareSerial.h>
SoftwareSerial gsm (9, 10);

int gasValue;
int fiftyFlag = 0;
int hundredFlag = 0;
int buzzerPin = 8;  // Assign buzzer pin

void setup() {
  Serial.begin(9600);
  gsm.begin(9600);
  gsm.println("AT+CNMI=2,2,0,0,0");
  delay(500);
  gsm.println("AT+CMGF=1");
  delay(1000);
  gsm.println((char)26);
  delay(500);

  pinMode(buzzerPin, OUTPUT); // Set buzzer pin as output
}

void loop() {
  gasValue = analogRead(A0);
  
  if (gasValue < 600 && fiftyFlag == 1) {
    fiftyFlag = 0;
    noTone(buzzerPin); // Matikan buzzer jika kondisi turun di bawah 50%
  }
  
  if (gasValue < 800 && hundredFlag == 1) {
    hundredFlag = 0;
    noTone(buzzerPin); // Matikan buzzer jika kondisi turun di bawah 100%
  }
  
  if (gasValue > 600 && gasValue < 800 && fiftyFlag == 0) {
    fiftyPercent();
    fiftyFlag = 1;
    tone(buzzerPin, 1000); // Nyalakan buzzer dengan frekuensi 1000 Hz untuk 50%
  }
  
  if (gasValue > 800 && hundredFlag == 0) {
    hundredPercent();
    hundredFlag = 1;
    tone(buzzerPin, 2000); // Nyalakan buzzer dengan frekuensi 2000 Hz untuk 100%
  }
  
  delay(1000); // Sesuaikan delay sesuai kebutuhan aplikasi
}

void fiftyPercent() {
  gsm.println("AT+CMGF=1");
  delay(500);
  gsm.println("AT+CMGS=\"+6281262022171\"\r"); // Ganti dengan nomor telepon Anda
  delay(500);
  gsm.println("awas ada api pak !!!");
  delay(100);
  gsm.println("Gas Leakage = 50%");
  delay(100);
  gsm.println((char)26);
  delay(500);
  Serial.println("Message sent - 50% leakage");
  gsm.println("AT+CMGF=1");
  delay(500);
}

void hundredPercent() {
  gsm.println("AT+CMGF=1");
  delay(500);
  gsm.println("AT+CMGS=\"+6281262022171\"\r"); // Ganti dengan nomor telepon Anda
  delay(500);
  gsm.println("awas ada api pak !!!");
  delay(100);
  gsm.println("Gas Leakage = 100%");
  delay(100);
  gsm.println((char)26);
  delay(500);
  Serial.println("Message sent - 100% leakage");
  gsm.println("AT+CMGF=1");
  delay(500);
}