#include <Wire.h>
#include <WiFi.h>
#include <PubSubClient.h>

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

// MQTT broker details
const char* mqtt_server = "localhost"; // You can use any public MQTT broker
const int mqtt_port = 1883;
const char* mqtt_topic = "sensor/ecg";

WiFiClient espClient;
PubSubClient client(espClient);

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

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

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ESP32Client")) {
      Serial.println("connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, mqtt_port);

  Wire.begin(21, 22); // SDA, SCL
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  Wire.requestFrom(0x57, 2); // Request 2 bytes from the custom chip
  while (Wire.available()) {
    uint8_t highByte = Wire.read();
    uint8_t lowByte = Wire.read();
    int heartRate = (highByte << 8) | lowByte;
    Serial.println(heartRate);
    
    String heartRateStr = String(heartRate);
    client.publish(mqtt_topic, heartRateStr.c_str());
  }

  delay(1000); // Send data every second
}