#include <WiFiManager.h>         // WiFiManager library
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>

// OLED display settings
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1 // We don't use reset pin on most OLEDs
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// DHT22 settings
#define DHTPIN 4          // GPIO pin for DHT22
#define DHTTYPE DHT22     // DHT22 sensor type
DHT dht(DHTPIN, DHTTYPE);

WiFiManager wifiManager; // Create WiFiManager instance

void setup() {
  // Start the Serial Monitor
  Serial.begin(115200);

  // Initialize DHT22
  dht.begin();

  // Initialize the OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  // Clear display buffer
  display.clearDisplay();
  
  // Start WiFiManager
  wifiManager.autoConnect("ESP32_DHT22_OLED");  // SSID for the Access Point

  // Once connected to WiFi, display success message
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("Connected to Wi-Fi");
  display.display();  // Update the display
  delay(2000);  // Wait for 2 seconds

  // Clear the screen for sensor data
  display.clearDisplay();
}

void loop() {
  // Read temperature and humidity from DHT22
  float humidity = dht.readHumidity();
  float temperatureF = dht.readTemperature(true); // Fahrenheit

  // Check if readings are valid
  if (isnan(humidity) || isnan(temperatureF)) {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }

  // Clear the display before showing new data
  display.clearDisplay();

  // Display temperature in Fahrenheit
  display.setCursor(0, 10);
  display.setTextSize(2);
  display.println("Temp:");
  display.setTextSize(2);
  display.setCursor(0, 30);
  display.print(temperatureF);
  display.println(" F");

  // Display humidity
  display.setCursor(0, 50);
  display.setTextSize(2);
  display.print("Hum:");
  display.setCursor(0, 70);
  display.print(humidity);
  display.println(" %");

  // Update the display with new values
  display.display();

  // Print the same data to Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(temperatureF);
  Serial.print(" F, Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  // Wait a few seconds between measurements
  delay(2000);
}