#include <WiFi.h>
#include <HTTPClient.h>
#include "DHT.h"

// -------- WiFi Setup --------
const char* ssid = "Wokwi-GUEST";   // Wokwi WiFi
const char* password = "";          // No password

// -------- ThingSpeak Setup --------
String apiKey = "39M9QPK8TMJD3QU1";     // Your Write API Key
const char* server = "http://api.thingspeak.com/update";

// -------- DHT22 Setup --------
#define DHTPIN 15
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  Serial.println("ESP32 + DHT22 + ThingSpeak");

  dht.begin();

  // Connect WiFi
  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("\nWiFi connected!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
}

void loop() {

  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Check sensor reading
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    delay(2000);
    return;
  }

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C | Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = String(server) + "?api_key=" + apiKey +
                 "&field1=" + String(temperature) +
                 "&field2=" + String(humidity);

    http.begin(url);
    int httpCode = http.GET();   // Send request
    http.end();

    if (httpCode > 0) {
      Serial.println("Data sent to ThingSpeak!");
    } else {
      Serial.println("Error sending data!");
    }
  }
  else {
    Serial.println("WiFi not connected!");
  }

  delay(20000);   // ThingSpeak minimum delay 15 sec
}