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

// Pin Definitions
#define LDR_PIN 3 // Digital pin for LDR
#define DHT_PIN 2 // Digital pin for DHT11
#define RAIN_SENSOR_PIN 4 // Digital pin for Rain Sensor

// DHT11 setup
// #define DHT_TYPE DHT11
#define DHT_TYPE DHT22
DHT dht(DHT_PIN, DHT_TYPE);

// LCD setup
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Weather thresholds
const int lightThreshold = HIGH;   // LDR threshold for "dark"
const int rainThreshold = HIGH;   // Rain sensor threshold for "rain"

const float highHumidity = 60.0;  // Humidity threshold for "very high"
const float mediumHumidity = 40.0; // Humidity threshold for "medium"

const float lowTemp = 20.0;        // Low temperature threshold
const float mediumTemp = 30.0;     // Medium temperature threshold
const float highTemp = 40.0;       // High temperature threshold

// Variables for sensor readings
int ldrValue;
bool isRaining;
float temperature;
float humidity;
String weatherStatus;

void setup() {
  // Initialize serial monitor
  Serial.begin(9600);

  // Initialize DHT sensor
  dht.begin();

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

  // Set pin modes
  pinMode(LDR_PIN, INPUT);
  pinMode(RAIN_SENSOR_PIN, INPUT);

  // Initial message
  lcd.setCursor(0, 0);
  lcd.print("Weather Sensor");
  lcd.setCursor(0, 1);
  lcd.print("Initializing...");
  delay(2000);
  lcd.clear();
}

void loop() {
  // Read sensor values
  ldrValue = digitalRead(LDR_PIN);
  isRaining = digitalRead(RAIN_SENSOR_PIN) == rainThreshold;
  temperature = dht.readTemperature();
  humidity = dht.readHumidity();

  // Error handling for DHT sensor
  if (isnan(temperature) || isnan(humidity)) {
    lcd.setCursor(0, 0);
    lcd.print("Sensor Error");
    delay(2000);
    return;
  }

  // Determine weather status
  if (ldrValue == lightThreshold && temperature < lowTemp && humidity > highHumidity && isRaining) {
    weatherStatus = "Very Cold Weather";
  } else if (ldrValue == lightThreshold && temperature >= lowTemp && temperature <= mediumTemp && humidity > mediumHumidity && isRaining) {
    weatherStatus = "Cold Weather";
  } else if (temperature >= lowTemp && temperature <= mediumTemp && humidity <= mediumHumidity && !isRaining) {
    weatherStatus = "Normal Weather";
  } else if (temperature > mediumTemp && humidity <= mediumHumidity) {
    weatherStatus = "Hot Weather";
  } else if (temperature > highTemp && humidity < mediumHumidity) {
    weatherStatus = "Very Hot Weather";
  } else {
    weatherStatus = "----";
  }

  // Display values on LCD
  lcd.setCursor(0, 0);
  lcd.print("T:");
  lcd.print(temperature, 1);
  lcd.print((char)223); // Degree symbol
  lcd.print("C ");
  lcd.print("H:");
  lcd.print(humidity, 1);
  lcd.print("%");

  lcd.setCursor(0, 1);
  lcd.print("L:");
  lcd.print(ldrValue == lightThreshold ? "Dark" : "Light");
  lcd.print(" R:");
  lcd.print(isRaining ? "Rain" : "NoRain");

  delay(3000);

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Status:");
  lcd.setCursor(0, 1);
  lcd.print(weatherStatus);

  // Print to serial monitor for debugging
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" C, Humidity: ");
  Serial.print(humidity);
  Serial.print(" %, LDR: ");
  Serial.print(ldrValue == lightThreshold ? "Dark" : "Light");
  Serial.print(", Rain: ");
  Serial.println(isRaining ? "Yes" : "No");
  Serial.print("Weather Status: ");
  Serial.println(weatherStatus);

  delay(7000); // Total delay = 10 seconds
}