// Blynk settings
#define BLYNK_TEMPLATE_ID "TMPL2CttZpODg"
#define BLYNK_TEMPLATE_NAME "Exercice2"
#define BLYNK_AUTH_TOKEN "RZ7VL8jjvgFV0pbN1VkZ57I3okUO7hP3"

#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>


char auth[] = BLYNK_AUTH_TOKEN;
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

// Define DHT sensor
#define DHTPIN 4
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);

// Variables for ThingSpeak update
unsigned long previousThingSpeakUpdate = 0;
const unsigned long thingSpeakUpdateInterval = 15000; // Update interval in milliseconds (15 seconds)

// Blynk virtual pins for displaying temperature and humidity
#define VIRTUAL_PIN_TEMP V1
#define VIRTUAL_PIN_HUMID V2

// Define pin numbers for LCD
#define I2C_ADDR 0x27
#define LCD_COLS 16
#define LCD_ROWS 2
LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLS, LCD_ROWS);

void setup() {
  // Debug console
  Serial.begin(115200);

  Blynk.begin(auth, ssid, pass);

  // Initialize DHT sensor
  dht.begin();

  // Connect to Wi-Fi
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

  // Initialize LCD
  lcd.init();
  lcd.backlight(); // turn on backlight
}

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

  // Update Blynk app with temperature and humidity values
  Blynk.virtualWrite(VIRTUAL_PIN_TEMP, temperature);
  Blynk.virtualWrite(VIRTUAL_PIN_HUMID, humidity);

  // Display temperature and humidity on LCD
  displayOnLCD(temperature, humidity);

  // Update ThingSpeak every specified interval
  unsigned long currentMillis = millis();
  if (currentMillis - previousThingSpeakUpdate >= thingSpeakUpdateInterval) {
    // Save the last update time
    previousThingSpeakUpdate = currentMillis;

    // Update ThingSpeak channel with temperature and humidity values using HTTP GET
    updateThingSpeakField(1, temperature);
    updateThingSpeakField(2, humidity);
  }

  // Add a delay to avoid continuous rapid readings
  delay(1000);
}

void updateThingSpeakField(int field, float value) {
  // You can replace this function with the ThingSpeak update logic if needed
  // For now, it's just a placeholder
}

// BLYNK_WRITE function to handle virtual pin writes
BLYNK_WRITE(V1) {
  // Get value of temperature directly from DHT sensor
  float temperature = dht.readTemperature();

  // Add your logic here based on the received temperature value
  Serial.print("Received Temperature: ");
  Serial.println(temperature);
}

BLYNK_WRITE(V2) {
  // Get value of humidity directly from DHT sensor
  float humidity = dht.readHumidity();

  // Add your logic here based on the received humidity value
  Serial.print("Received Humidity: ");
  Serial.println(humidity);
}

// Function to display temperature and humidity on LCD
void displayOnLCD(float temp, float humid) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temp);
  lcd.print("C");
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humid);
  lcd.print("%");
}