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

// Define constants for I2C LCD and DHT22 sensor
#define DHTPIN 4 // Digital pin connected to the DHT sensor
#define DHTTYPE DHT22 // DHT 22 (or AM2302) sensor
#define LCD_ADDR 0x27 // I2C address of the LCD (check your LCD's datasheet)
#define LCD_COLS 20   // Number of columns on the LCD
#define LCD_ROWS 4    // Number of rows on the LCD

// Define pin for soil moisture sensor and LED (adjust as needed)
const int SOIL_MOISTURE_PIN = 5;
const int PUMP_LED_PIN = 2; // Replace with the LED pin connected to the pump

// Variables for sensor readings
float temp, humidity;
int soilMoisture;

// LiquidCrystal_I2C object for LCD control
LiquidCrystal_I2C lcd(LCD_ADDR, LCD_COLS, LCD_ROWS);

// DHT object for temperature and humidity readings
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600); // Optional for serial communication debugging
  lcd.init();       // Initialize the LCD
  lcd.backlight();  // Turn on LCD backlight

  lcd.setCursor(0, 0);  // Set cursor position (0, 0)
  lcd.print("Initializing...");

  dht.begin();       // Start DHT sensor
  pinMode(SOIL_MOISTURE_PIN, INPUT); // Set soil moisture pin as input
  pinMode(PUMP_LED_PIN, OUTPUT);    // Set LED pin as output
}

void loop() {
  // Read temperature and humidity from DHT sensor
  temp = dht.readTemperature();
  humidity = dht.readHumidity();

  // Check if any reads failed and exit early (to avoid NaN)
  if (isnan(temp) || isnan(humidity)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Read soil moisture value
  soilMoisture = analogRead(SOIL_MOISTURE_PIN);

  // Calculate soil moisture percentage with adjusted range (1% to 100%)
  int soilMoisturePercent = map(soilMoisture, 0, 1023, 1, 100);

  // Control pump based on soil moisture threshold
  bool pumpStatus = soilMoisturePercent < 80; // Turn pump on if below 80%
  digitalWrite(PUMP_LED_PIN, pumpStatus);  // LED on when pump is on (direct logic)

  // Display readings on LCD
  lcd.clear();

  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temp);
  lcd.print("°C");

  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print("%");

  lcd.setCursor(0, 2);
  lcd.print("Soil Moisture: ");
  lcd.print(soilMoisturePercent);
  lcd.print("%");

  lcd.setCursor(0, 3);
  lcd.print("Pump: ");
  lcd.print(pumpStatus ? "ON" : "OFF");

  delay(2000); // Update readings every 2 seconds
}