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

// Pin dan tipe sensor
#define DHTPIN 2          // Pin sensor DHT22
#define DHTTYPE DHT22

#define RELAY_PIN 12      // Pin relay untuk mengontrol lampu
#define BUZZER_PIN 10     // Pin buzzer
#define LDR_PIN A0       // Pin untuk sensor LDR

DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2); // LCD 16x2 dengan alamat 0x27

// Simulasi pembacaan sensor gas MQ-2 dengan range 0-350 (bisa lebih)
int readGasValue() {
  return random(0, 351); // nilai gas antara 0 sampai 350
}

void setup() {
  Serial.begin(9600);
  dht.begin();
  lcd.init();
  lcd.backlight();
  pinMode(RELAY_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(LDR_PIN, INPUT); // Set pin LDR sebagai input
  digitalWrite(RELAY_PIN, LOW);  // Kipas mati awal
  digitalWrite(BUZZER_PIN, LOW); // Buzzer mati awal
  randomSeed(analogRead(0));     // Seed random untuk simulasi gas
}

void loop() {
  float suhu = dht.readTemperature();

  if (isnan(suhu)) {
    Serial.println("Gagal membaca sensor DHT!");
    delay(3000);
    return;
  }

  int gasValue = readGasValue();
  int ldrValue = analogRead(LDR_PIN); // Membaca nilai dari sensor LDR

  // Kontrol relay (kipas) berdasarkan suhu
  if (suhu > 25.0) {
    digitalWrite(RELAY_PIN, HIGH); // Kipas menyala
  } else {
    digitalWrite(RELAY_PIN, LOW);  // Kipas mati
  }

  // Kontrol buzzer berdasarkan gas (menyala jika gas bocor)
  if (gasValue >= 320) {
    digitalWrite(BUZZER_PIN, HIGH); // Buzzer aktif
  } else {
    digitalWrite(BUZZER_PIN, LOW);  // Buzzer mati
  }

  // Tampilan suhu di LCD (tampilan 1)
  lcd.clear();
  lcd.setCursor(0, 0);
  if (suhu > 25.0) {
    lcd.print("Suhu Over     ");
  } else {
    lcd.print("Suhu Normal   ");
  }
  lcd.setCursor(0, 1);
  lcd.print("Suhu: ");
  lcd.print(suhu, 1);
  lcd.print(" C");
  delay(4000);

  // Tampilan gas di LCD (tampilan 2)
  lcd.clear();
  lcd.setCursor(0, 0);
  if (gasValue <= 210) {
    lcd.print("Gas Normal   ");
  } else if (gasValue < 320) {
    lcd.print("Waspada      ");
  } else {
    lcd.print("Gas Bocor    ");
  }
  lcd.setCursor(0, 1);
  lcd.print("Nilai: ");
  lcd.print(gasValue);
  lcd.print("   ");
  delay(4000);

  // Output debug di Serial Monitor
  Serial.print("Suhu: ");
  Serial.print(suhu, 1);
  Serial.print(" C, Gas Nilai: ");
  Serial.print(gasValue);
  Serial.print(", Relay (Kipas): ");
  Serial.print(digitalRead(RELAY_PIN) ? "ON" : "OFF");
  Serial.print(", Buzzer: ");
  Serial.println(digitalRead(BUZZER_PIN) ? "ON" : "OFF");

  // Kontrol relay berdasarkan nilai LDR
  if (ldrValue < 500) { // Threshold LDR, sesuaikan sesuai kebutuhan
    digitalWrite(RELAY_PIN, HIGH); // Relay menyala (misal untuk lampu)
  } else {
    digitalWrite(RELAY_PIN, LOW);  // Relay mati
  }

  // Tampilkan nilai LDR di Serial Monitor
  Serial.print("Nilai LDR: ");
  Serial.println(ldrValue);

  delay(3000);
}