#include <Wire.h>
#include <WiFi.h>
#include <DHT.h>
#include <PubSubClient.h>
#include <LiquidCrystal_I2C.h>

// Define pin connections
#define DHT_PIN 14        // Pin where the DHT22 is connected
#define DHTTYPE DHT22     // DHT22 sensor type
#define BUZZER_PIN 25     // Pin where the buzzer is connected
#define RED_LED_PIN 26    // Pin where the red LED is connected
#define PULSE_SENSOR_PIN 34 // Pin where the pulse sensor is connected

#define MQTT_SERVER "broker.emqx.io"
#define MQTT_PORT 1883

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

#define MQTT_TOPIC_HR "/heartRate"
#define MQTT_TOPIC_TEMP "/tempValue"
#define MQTT_TOPIC_HUM "/humValue"

// Create instances of the sensors and MQTT client
DHT dht(DHT_PIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2); // Set the LCD address to 0x27 for a 16 chars and 2 line display

WiFiClient espClient;
PubSubClient client(espClient);

// Variables for pulse sensor
int pulseValue = 0;
int threshold = 600; // Example threshold value, you might need to calibrate it

void setup() {
  // Initialize serial communication
  Serial.begin(115200);

  // Initialize the sensors
  dht.begin();
  
  // Initialize the LCD
  lcd.init();
  lcd.backlight();

  // Initialize the buzzer and LED pins
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(RED_LED_PIN, OUTPUT);

  // Initialize the pulse sensor pin
  pinMode(PULSE_SENSOR_PIN, INPUT);

  // Initialize WiFi and MQTT
  connectToWiFi();
  client.setServer(MQTT_SERVER, MQTT_PORT);
}

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

  // Read temperature and humidity from DHT22 sensor
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();

  // Read the pulse value from the pulse sensor
  pulseValue = analogRead(PULSE_SENSOR_PIN);

  // Display the temperature, humidity, and pulse rate on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print("C");

  lcd.setCursor(0, 1);
  lcd.print("Hum: ");
  lcd.print(humidity);
  lcd.print("%");

  delay(2000); // Wait for 2 seconds

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Pulse: ");
  lcd.print(pulseValue);

  // Check conditions for asthma warning
  if (temperature >= 30.0 && humidity >= 70.0 && pulseValue > threshold) {
    // Trigger the buzzer and red LED if conditions are met
    digitalWrite(BUZZER_PIN, HIGH);
    digitalWrite(RED_LED_PIN, HIGH);

    lcd.setCursor(0, 1);
    lcd.print("Patient Not Safe");
  } else {
    // Turn off the buzzer and red LED if conditions are not met
    digitalWrite(BUZZER_PIN, LOW);
    digitalWrite(RED_LED_PIN, LOW);

    lcd.setCursor(0, 1);
    lcd.print("Patient Safe");
  }

  delay(2000); // Wait for 2 seconds before the next loop

  // Publish sensor data to MQTT
  client.publish(MQTT_TOPIC_HR, String(pulseValue).c_str());
  client.publish(MQTT_TOPIC_TEMP, String(temperature).c_str());
  client.publish(MQTT_TOPIC_HUM, String(humidity).c_str());
}

void connectToWiFi() {
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

void reconnect() {
  while (!client.connected()) {
    if (client.connect("esp32_health_monitor")) {
      Serial.println("Connected to MQTT");
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      Serial.println(" Retrying in 5 seconds...");
      delay(5000);
    }
  }
}