#include <WiFi.h>
#include <ThingSpeak.h>

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

WiFiClient client;

// Replace with your ThingSpeak details
unsigned long channelID = 3433689;
const char* writeAPIKey = "E0KQNIYKTS91SV4G";

// Analog sensor pin
const int sensorPin = 0;   // ESP0 (GPIO0)

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

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

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

  Serial.println("\nWiFi Connected");
  ThingSpeak.begin(client);
}

void loop() {

  // Read analog value
  int adcValue = analogRead(sensorPin);

  // Convert to voltage
  float voltage = adcValue * (3.3 / 4095.0);

  // LM35 formula: 10 mV = 1°C
  // (For Wokwi Analog NTC this is only an approximation.)
  float temperature = voltage * 100.0;

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

  ThingSpeak.setField(1, temperature);

  int status = ThingSpeak.writeFields(channelID, writeAPIKey);

  if (status == 200) {
    Serial.println("Data uploaded successfully");
  } else {
    Serial.print("Upload failed. Error: ");
    Serial.println(status);
  }

  delay(15000);   // ThingSpeak requires at least 15 seconds between updates
}