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

// Pin definitions
#define DHTPIN 35       // DHT22 data pin connected to D35
#define DHTTYPE DHT22   // DHT 22 (AM2302)
#define SOIL_PIN 34     // Soil moisture sensor pin connected to D34
#define DS18B20_PIN 32  // DS18B20 data pin connected to D32
#define LED_PIN 2       // LED pin connected to D2

// Initialize the DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// Initialize OneWire and DS18B20 sensors
OneWire oneWire(DS18B20_PIN);
DallasTemperature ds18b20(&oneWire);

// Initialize LCD (I2C Address 0x27, 16 characters and 2 lines)
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Variables for sensor readings
float temperatureDHT, humidity, ds18b20Temperature;
int soilMoistureValue, soilMoisturePercent;

// Threshold values for LED activation
float tempThreshold = 30.0;   // Temperature threshold for LED (in Celsius)
float humidityThreshold = 40.0; // Humidity threshold for LED (in percentage)
int soilMoistureThreshold = 30; // Soil moisture threshold (in percentage)

void setup() {
  Serial.begin(115200);    // Start Serial communication

  // Initialize sensors
  dht.begin();
  ds18b20.begin();

  // Initialize the LCD
  lcd.init();
  lcd.backlight();

  // Set LED pin as output
  pinMode(LED_PIN, OUTPUT);

  // Welcome message on LCD
  lcd.setCursor(0, 0);
  lcd.print("Smart Irrigation");
  lcd.setCursor(0, 1);
  lcd.print("System Starting");
  delay(2000);
  lcd.clear();
}

void loop() {
  // Reading DHT22 sensor
  temperatureDHT = dht.readTemperature();
  humidity = dht.readHumidity();

  // Read soil moisture sensor
  soilMoistureValue = analogRead(SOIL_PIN);
  soilMoisturePercent = map(soilMoistureValue, 4095, 0, 0, 100);

  // Request temperature from DS18B20 sensor
  ds18b20.requestTemperatures();
  ds18b20Temperature = ds18b20.getTempCByIndex(0);

  // Check for proper DS18B20 reading
  if (ds18b20Temperature == DEVICE_DISCONNECTED_C) {
    Serial.println("Error: DS18B20 sensor disconnected.");
    lcd.setCursor(0, 0);
    lcd.print("DS18B20 Error");
  } else {
    // Display readings on LCD
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(temperatureDHT);
    lcd.print("C ");

    lcd.setCursor(0, 1);
    lcd.print("Hum: ");
    lcd.print(humidity);
    lcd.print("% SM:");
    lcd.print(soilMoisturePercent);
  }

  // Print to Serial Monitor for debugging
  Serial.print("DHT22 Temp: ");
  Serial.print(temperatureDHT);
  Serial.print("C, Humidity: ");
  Serial.print(humidity);
  Serial.print("%, Soil Moisture: ");
  Serial.print(soilMoisturePercent);
  Serial.print("%, DS18B20 Temp: ");
  Serial.println(ds18b20Temperature);

  // LED control based on thresholds
  if (temperatureDHT > tempThreshold && humidity < humidityThreshold && soilMoisturePercent < soilMoistureThreshold) {
    digitalWrite(LED_PIN, HIGH);  // Turn on LED
  } else {
    digitalWrite(LED_PIN, LOW);   // Turn off LED
  }

  delay(2000); // Wait for 2 seconds before next reading
}