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

#define DHTPIN 26        // DHT22 pin
#define DHTTYPE DHT22
#define THERMISTOR_PIN 34 // Analog input (simulate with potentiometer)

const char* ssid = "Wokwi-GUEST";        // WiFi credentials
const char* password = "";               // Leave blank for open network
const char* mqtt_server = "mqtt.eclipseprojects.io"; // MQTT broker address

WiFiClient espClient;
PubSubClient client(espClient);
DHT dht(DHTPIN, DHTTYPE);  // Initialize DHT sensor

void setup_wifi() {
  Serial.print("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("Connected to WiFi");
}

void reconnect() {
  // Loop until we're reconnected to the broker
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ESP32Client")) {
      Serial.println("Connected to MQTT Broker");
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  dht.begin();
  setup_wifi();  // Connect to WiFi
  client.setServer(mqtt_server, 1883);  // Set MQTT broker address
}

void loop() {
  if (!client.connected()) {
    reconnect();  // Reconnect to MQTT broker if disconnected
  }
  client.loop();  // Ensure the connection stays alive

  // Read sensor data
  float temp = dht.readTemperature();
  float hum = dht.readHumidity();
  int thermistorRaw = analogRead(THERMISTOR_PIN);
  float thermistorTemp = map(thermistorRaw, 0, 4095, 10, 50); // Rough estimate of temperature from thermistor

  // Check if sensor readings are valid
  if (!isnan(temp) && !isnan(hum)) {
    // Create payload string
    String payload = String("{\"temperature\":") + temp + 
                     ",\"humidity\":" + hum + 
                     ",\"thermistor\":" + thermistorTemp + "}";

    // Publish to MQTT topic
    client.publish("iot/sensor/data", payload.c_str());

    // Print payload to serial monitor for debugging
    Serial.println(payload);
  } else {
    Serial.println("Failed to read from DHT sensor!");
  }

  // Delay for 3 seconds before taking new readings
  delay(500);
}