#include <DHT.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h> // Include the LCD library
#include <Servo.h> // Include the Servo library

#define DHTPIN 2         // Pin where the DHT22 sensor is connected
#define DHTTYPE DHT22    // Define the DHT22 sensor type

DHT dht(DHTPIN, DHTTYPE);  // Create DHT object

LiquidCrystal_I2C lcd(0x27, 16, 2); // Create LCD object with I2C address 0x27 (default)

// Define the number of LEDs in the Wokwi LED Bar Graph
const int ledPins[] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12}; // Connect the LED bar graph to these pins
const int numLEDs = 10; // Number of LEDs in the bar graph

Servo myServo;  // Create servo object to control the servo motor

// Define the initial servo position and speed multiplier
int servoPosition = 0;
float speedMultiplier = 1.0;

// Define the Wokwi LED on pin 13
const int ledPin = 13; // Wokwi LED connected to pin 13

void setup() {
  Serial.begin(9600);           // Start serial communication at 9600 baud
  Serial.println("DHT sensor test");
  
  dht.begin();                  // Initialize the DHT sensor
  lcd.begin(16, 2);             // Initialize the LCD screen (16x2)

  lcd.print("DHT22 Sensor");    // Display initial message on LCD
  delay(2000);                  // Wait for a while to show the initial message
  lcd.clear();                  // Clear the screen
  
  // Initialize the LED bar graph pins
  for (int i = 0; i < numLEDs; i++) {
    pinMode(ledPins[i], OUTPUT);  // Set each LED pin as an output
  }

  // Attach the servo to pin 13
  myServo.attach(13);

  // Initialize the Wokwi LED pin
  pinMode(ledPin, OUTPUT);  // Set the LED pin as an output
}

void loop() {
  delay(2000);                  // Wait 2 seconds before reading again

  // Read temperature and humidity from the DHT22 sensor
  float h = dht.readHumidity();  // Read humidity
  float t = dht.readTemperature(); // Read temperature

  // Check if the readings are valid (returns NaN if invalid)
  if (isnan(h) || isnan(t)) {
    lcd.clear();
    lcd.print("Error reading!");
    Serial.println("Failed to read from DHT sensor!");
    return; // Skip the rest of the loop and try again
  }

  // Display the temperature and humidity values on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);           // Set cursor to the first row
  lcd.print("Temp: ");
  lcd.print(t);                  // Print temperature on the LCD
  lcd.print(" C");

  lcd.setCursor(0, 1);           // Set cursor to the second row
  lcd.print("Humidity: ");
  lcd.print(h);                  // Print humidity on the LCD
  lcd.print(" %");

  // Map the temperature to the LED bar graph
  int tempLEDs = mapTemperatureToLED(t);

  // Update the LED bar graph based on the temperature
  updateLEDs(tempLEDs);

  // Control the servo motor based on the temperature
  if (t > 20) {
    // Increase speed multiplier for every 5°C above 20°C
    int speedLevel = (t - 20) / 5;  // How many 5°C increments above 20°C
    speedMultiplier = 1.0 + (speedLevel * 0.2);

    // Rotate the servo continuously and increase speed
    for (servoPosition = 0; servoPosition <= 180; servoPosition++) {
      myServo.write(servoPosition);  // Rotate servo to current position
      delay(15 / speedMultiplier);   // Delay adjusted by speedMultiplier
    }
    for (servoPosition = 180; servoPosition >= 0; servoPosition--) {
      myServo.write(servoPosition);  // Rotate servo back
      delay(15 / speedMultiplier);   // Delay adjusted by speedMultiplier
    }
  } else {
    // If temperature is below or equal to 20°C, stop the servo
    myServo.write(0);  // Set servo to initial position (0 degrees)
  }

  // Blink the Wokwi LED if the temperature is above 40°C
  if (t > 40) {
    digitalWrite(ledPin, HIGH);  // Turn on the LED
    delay(500);                  // Wait for 500 milliseconds (0.5 seconds)
    digitalWrite(ledPin, LOW);   // Turn off the LED
    delay(500);                  // Wait for another 500 milliseconds (0.5 seconds)
  } else {
    // If the temperature is below or equal to 40°C, keep the LED off
    digitalWrite(ledPin, LOW);   // Ensure the LED is off
  }

  // Print the temperature and humidity to the Serial Monitor as well
  Serial.print("Temperature: ");
  Serial.println(t);
  Serial.print("Humidity: ");
  Serial.println(h);
}

// Function to map temperature (-40 to 80°C) to LED range (0 to 10 LEDs)
int mapTemperatureToLED(float temp) {
  // Map the temperature from the range of -40°C to 80°C to the range 0 to numLEDs
  int mappedLED = map(temp, -40, 80, 0, numLEDs);

  // Ensure that the value stays within the valid range (0 to numLEDs)
  if (mappedLED < 0) {
    mappedLED = 0;
  }
  if (mappedLED > numLEDs) {
    mappedLED = numLEDs;
  }

  return mappedLED;
}

// Function to update the LED bar graph based on the mapped temperature
void updateLEDs(int numActiveLEDs) {
  // Loop through all LEDs (0 to numLEDs - 1) and turn on the corresponding LEDs
  for (int i = 0; i < numLEDs; i++) {
    if (i < numActiveLEDs) {
      digitalWrite(ledPins[i], HIGH);  // Turn on the LED
    } else {
      digitalWrite(ledPins[i], LOW);   // Turn off the LED
    }
  }
}