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

LiquidCrystal_I2C lcd(0x27, 20, 4);  // Initialize LCD with I2C address 0x27, 20 columns, 4 rows
const int relayPin = 26;             // GPIO pin to which the relay is connected

void setup() {
  Wire.begin(23, 22);                // Initialize I2C communication with SDA 23 and SCL 22
  Serial.begin(9600);                // Initialize Serial communication at 9600 baud rate
  lcd.init();                        // Initialize the LCD
  lcd.backlight();                   // Turn on the LCD backlight
  pinMode(relayPin, OUTPUT);         // Set the relay pin as an output
  digitalWrite(relayPin, HIGH);      // Initially turn the relay OFF (HIGH means OFF for active-low relay)
}

void loop() {
  // Step 1: Read soil moisture value from the sensor
  int16_t moistureValue = analogRead(34); // Read the analog value from moisture sensor

  // Step 2: Determine the moisture status based on the sensor value
  String moistureStatus = (moistureValue < 30) ? "DRY" : (moistureValue > 70) ? "WET" : "OK";
  
  // Step 3: Control the relay (pump) based on the soil moisture reading
  if (moistureValue < 30) {
    // Soil is dry, turn on the pump (relay on)
    digitalWrite(relayPin, LOW);       // LOW activates the relay for active-low relays
  } else {
    // Soil is not dry, turn off the pump (relay off)
    digitalWrite(relayPin, HIGH);      // HIGH deactivates the relay
  }
  
  // Step 4: Display on the LCD
  lcd.clear();                         // Clear the LCD before displaying new content
  lcd.setCursor(0, 0);                 // Set cursor to the first line
  lcd.print("Moisture: ");
  lcd.print(moistureValue);            // Display actual moisture value
  
  lcd.setCursor(0, 1);                 // Move cursor to the second line
  lcd.print("Status: ");
  lcd.print(moistureStatus);           // Show "DRY", "OK", or "WET" on the LCD
  
  lcd.setCursor(0, 2);                 // Move cursor to the third line
  lcd.print("Pump: ");
  lcd.print(moistureValue < 30 ? "ON  " : "OFF "); // Display pump status

  delay(1000);                         // Wait for 1 second before the next loop iteration
}