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

// ====== DHT CONFIG ======
#define DHTPIN 4
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

// ====== WIFI ======
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// ====== THINGSPEAK ======
unsigned long channelID = "GRK_Temp_Alert";     // Replace
const char* writeAPIKey = "Z2NVHMGU4EQH7VN9"; // Replace

// ====== THRESHOLD ======
float threshold = 55.0;

void setup() {
  Serial.begin(115200);

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

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

  Serial.println("\nWiFi Connected!");

  dht.begin();
}

void loop() {

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

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

  Serial.println("-------------");
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  // ====== SEND DATA TO THINGSPEAK ======
  if (WiFi.status() == WL_CONNECTED) {

    HTTPClient http;

    String url = "http://api.thingspeak.com/update?api_key=" + String(writeAPIKey) +
                 "&field1=" + String(temperature) +
                 "&field2=" + String(humidity);

    http.begin(url);
    int httpResponseCode = http.GET();

    Serial.print("ThingSpeak Response: ");
    Serial.println(httpResponseCode);

    http.end();
  }

  // ====== LOCAL ALERT (SERIAL) ======
  if (temperature > threshold) {
    Serial.println("⚠️ ALERT: Temperature exceeded threshold!");
  }

  // ThingSpeak requires minimum 15 sec delay
  delay(15000);
}