#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Servo.h>
#include <DHT.h>

// Inisialisasi LCD (alamat I2C: 0x27, ukuran 16x2)
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Pin sensor dan komponen
#define trigPin 9
#define echoPin 10
#define gasPin A0
#define pirPin 2
#define ldrPin A1
#define dhtPin 3
#define switchPin 4
#define buzzerPin 6
#define ledRedPin 7
#define ledGreenPin 8

Servo myservo;
DHT dht(dhtPin, DHT22); // DHT22

void setup() {
  // Inisialisasi pin
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(gasPin, INPUT);
  pinMode(pirPin, INPUT);
  pinMode(ldrPin, INPUT);
  pinMode(switchPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledRedPin, OUTPUT);
  pinMode(ledGreenPin, OUTPUT);

  // Inisialisasi servo
  myservo.attach(9);
  
  // Inisialisasi LCD dan DHT22
  lcd.begin(16, 2); // Menentukan 16 kolom dan 2 baris
  lcd.backlight();
  dht.begin();
  
  // Tampilkan pesan awal di LCD
  lcd.setCursor(0, 0);
  lcd.print("Sistem Start...");
  delay(2000);
  lcd.clear();
}

void loop() {
  // Baca status switch (menghidupkan/mematikan sistem)
  int switchState = digitalRead(switchPin);

  if (switchState == HIGH) {
    lcd.setCursor(0, 0);
    lcd.print("Sistem Aktif");

    // 1. Jarak dari sensor Ultrasonik
    long duration, distance;
    digitalWrite(trigPin, LOW);
    delayMicroseconds(2);
    digitalWrite(trigPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(trigPin, LOW);
    duration = pulseIn(echoPin, HIGH);
    distance = (duration / 2) / 29.1;  // Menghitung jarak dalam cm

    // 2. Gas Sensor (MQ-2)
    int gasLevel = analogRead(gasPin);

    // 3. PIR Sensor (Passive Infrared)
    int pirState = digitalRead(pirPin);

    // 4. LDR (Light Sensor)
    int ldrValue = analogRead(ldrPin);

    // 5. DHT22 Sensor (Suhu dan Kelembaban)
    float temperature = dht.readTemperature();
    float humidity = dht.readHumidity();

    // Tampilkan hasil sensor di LCD
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(temperature);
    lcd.print("C");

    lcd.setCursor(0, 1);
    lcd.print("Gas: ");
    lcd.print(gasLevel);

    // Logika sistem untuk LED, Servo, dan Buzzer berdasarkan sensor
    if (gasLevel > 300 || pirState == HIGH || distance < 50) {
      // Kondisi berbahaya (Gas, Gerakan, Jarak terlalu dekat)
      digitalWrite(ledRedPin, HIGH);   // Nyalakan LED Merah
      digitalWrite(ledGreenPin, LOW);  // Matikan LED Hijau
      digitalWrite(buzzerPin, HIGH);   // Nyalakan Buzzer
      myservo.write(90);                // Gerakkan Servo

      lcd.setCursor(0, 1);
      lcd.print("Danger!          ");
    } else {
      // Kondisi aman
      digitalWrite(ledGreenPin, HIGH); // Nyalakan LED Hijau
      digitalWrite(ledRedPin, LOW);    // Matikan LED Merah
      digitalWrite(buzzerPin, LOW);    // Matikan Buzzer
      myservo.write(0);                 // Servo kembali ke posisi awal

      lcd.setCursor(0, 1);
      lcd.print("All Safe         ");
    }

    delay(1000);  // Pembaruan setiap 1 detik

  } else {
    // Jika switch dimatikan, sistem dalam mode standby
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Sistem Mati");
    digitalWrite(ledGreenPin, LOW);
    digitalWrite(ledRedPin, LOW);
    digitalWrite(buzzerPin, LOW);
    myservo.write(0);  // Servo kembali ke posisi awal
  }
}