#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Adjust the address and dimensions if your LCD is different

#define sensor_pin 0 // Adjust the pin if connected to a different analog pin
int read_ADC;
int ntu;

#define RELAY1_PIN 12  // Define the pins for the relays
#define RELAY2_PIN 13
#define RELAY3_PIN 14

bool relay2_active = false;  // Flag to track whether relay 2 is active
unsigned long relay2_start_time = 0;  // Time when relay 2 was activated

void setup() {
  pinMode(sensor_pin, INPUT);
  pinMode(RELAY1_PIN, OUTPUT);
  pinMode(RELAY2_PIN, OUTPUT);
  pinMode(RELAY3_PIN, OUTPUT);
  
  Serial.begin(115200);
  
  lcd.init(); //menginisialisasi tampilan
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("   Welcome To   ");
  lcd.setCursor(0, 1);
  lcd.print("Turbidity Sensor");
  delay(2000);
  lcd.clear();
}

void loop() {
  read_ADC = analogRead(sensor_pin);
  if (read_ADC > 208) read_ADC = 208;

  ntu = map(read_ADC, 0, 208, 300, 0);

  lcd.setCursor(0, 0);
  lcd.print("Turbidity: ");
  lcd.print(ntu);
  lcd.print("  ");

  lcd.setCursor(0, 1);
  if (ntu < 10) {
    lcd.print("Water Very Clean");
    activateRelay(1);
  }
  else if (ntu >= 10 && ntu < 25) {
    lcd.print("Water Norm Clean");
    activateRelay(2);
  }
  else {
    lcd.print("Water Very Dirty");
    if (!relay2_active) {
      relay2_active = true;
      relay2_start_time = millis();
    }
    activateRelay(3);
  }

  delay(200);
}

void activateRelay(int relayNumber) {
  switch (relayNumber) {
    case 1:
      digitalWrite(RELAY1_PIN, HIGH);
      digitalWrite(RELAY2_PIN, LOW);
      digitalWrite(RELAY3_PIN, LOW);
      break;
    case 2:
      digitalWrite(RELAY1_PIN, LOW);
      digitalWrite(RELAY2_PIN, HIGH);
      digitalWrite(RELAY3_PIN, LOW);
      break;
    case 3:
      digitalWrite(RELAY1_PIN, LOW);
      digitalWrite(RELAY2_PIN, HIGH);
      //digitalWrite(RELAY3_PIN, LOW); // Activate relay 3
      if (millis() - relay2_start_time >= 10000) {  // Check if 10 seconds have passed since relay 2 was activated
        digitalWrite(RELAY3_PIN, HIGH); // Turn off relay 2
      }
      break;
    default:
      // Invalid relay number
      break;
  }
}