/******************************************************
 * COURSE CODE: DFN40312 - Embedded Internet of Things
 * PRACTICAL EXERCISE: 2 (Manufacturing Industry)
 * PROJECT TITLE: Smart Machine Vibration Monitoring System
 * STUDENT NAME: NURKHAIRUNASS BINTI ABDULLAH & JESSYCIA CANKEH 
 * STUDENT ID: 20DDT23F1065 & 20DDT22F2009
 * CLASS: DDT5G & DDT6F
 * LECTURER: SIR TS. FAIZ BIN TONY
 * OBJECTIVE: 
 *   To design an IoT system that detects abnormal machine vibration 
 *   in manufacturing environments to reduce downtime and improve efficiency.
 ******************************************************/


#include "DHTesp.h"

#define DHT_PIN 4
#define VIBRATION_PIN 34
#define ALERT_LED 13

DHTesp dhtSensor;

// ===== Simple function (1 function only) =====
void readDHT(float &temp, float &hum) {
  TempAndHumidity data = dhtSensor.getTempAndHumidity();

  if (isnan(data.temperature) || isnan(data.humidity)) {
    Serial.println("DHT22 read error!");
    temp = 0;
    hum = 0;
  } else {
    temp = data.temperature;
    hum = data.humidity;
  }
}

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

  pinMode(VIBRATION_PIN, INPUT);
  pinMode(ALERT_LED, OUTPUT);

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  Serial.println("=======================================");
  Serial.println("IoT Predictive Maintenance System (Hybrid Version)");
  Serial.println("=======================================");
  delay(2000);
}

void loop() {
  float temperature, humidity;

  // ===== Read sensors =====
  readDHT(temperature, humidity);      // simple function
  int vibration = analogRead(VIBRATION_PIN); // student style

  // ===== Display data =====
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C | Humidity: ");
  Serial.print(humidity);
  Serial.print(" % | Vibration: ");
  Serial.println(vibration);

  // ===== Simple alert logic =====
  if (temperature > 40 || vibration > 2500) {
    digitalWrite(ALERT_LED, HIGH);
    Serial.println("⚠️ WARNING: Machine at risk!");
  } else {
    digitalWrite(ALERT_LED, LOW);
    Serial.println("✅ Machine operating normally.");
  }

  Serial.println("---------------------------------------");
  delay(2000);
}