TrackProd: IIoT QR Traceability System

/*
===========================================================
   TRACKPROD IIoT SYSTEM - INDUSTRIAL TRACEABILITY
===========================================================

Este sistema realiza:

1. Lectura de cdigo QR (identificacin del producto)
2. Visualizacin en pantalla Nextion
3. Comunicacin inalmbrica LoRa (envo y recepcin)
4. Confirmacin desde interfaz (botn en Nextion)
5. Control de torre de sealizacin industrial:
      - Verde: operacin correcta
      - Amarillo: advertencia
      - Rojo: error total
      - Azul: fallo de comunicacin LoRa
6. Activacin de buzzer en fallos
7. Monitoreo de sensores industriales

Hardware (segn diagrama):
- Arduino UNO Q (main controller)
- Mdulo LoRa RA-02 (comunicacin)
- Pantalla Nextion (interfaz HMI)
- Mdulo de rels (control de torreta)
- Torreta luminosa industrial
- Buzzer
- Lector QR (serial)
- Fuente AC-DC (120V DC)

===========================================================
*/

#include <SPI.h>
#include <LoRa.h>

// ================= PINES =================

// Rels (torreta)
#define RELAY_GREEN 3     // Luz verde (OK)
#define RELAY_YELLOW 4    // Luz amarilla (advertencia)
#define RELAY_RED 5       // Luz roja (error)

// Buzzer
#define BUZZER 6

// LED indicador de estado LoRa
#define LED_BLUE 11       //  Error de comunicacin

// Sensores (simulacin / entrada digital)
#define SENSOR1 7
#define SENSOR2 8
#define SENSOR3 A0

// Pines LoRa (RA-02 / SX1278)
#define LORA_SS 10
#define LORA_RST 9
#define LORA_DIO0 2

// ================= VARIABLES =================

String qrData = "";        // QR ledo
String loraReceived = ""; // Datos recibidos LoRa

unsigned long lastLoRaTime = 0; // Control de comunicacin

// ================= SETUP =================
void setup() {

  // Comunicacin serial
  Serial.begin(9600);     // Debug
  Serial1.begin(9600);    // QR
  Serial2.begin(9600);    // Nextion

  // Configuracin de salidas
  pinMode(RELAY_GREEN, OUTPUT);
  pinMode(RELAY_YELLOW, OUTPUT);
  pinMode(RELAY_RED, OUTPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(LED_BLUE, OUTPUT);

  // Sensores
  pinMode(SENSOR1, INPUT);
  pinMode(SENSOR2, INPUT);
  pinMode(SENSOR3, INPUT);

  digitalWrite(LED_BLUE, LOW);

  // Inicializacin LoRa
  LoRa.setPins(LORA_SS, LORA_RST, LORA_DIO0);

  if (!LoRa.begin(433E6)) {
    Serial.println("Error LoRa");
    digitalWrite(LED_BLUE, HIGH); //  Indica fallo
    while (1); // Detener sistema
  }

  Serial.println("LoRa OK");

  resetOutputs();
}

// ================= LOOP =================
void loop() {

  readQR();         // Leer QR
  receiveLoRa();    // Recibir datos LoRa
  readNextion();    // Leer botn Nextion
  checkSensors();   // Evaluar sensores

  // Verificar comunicacin LoRa (timeout)
  if (millis() - lastLoRaTime > 5000) {
    digitalWrite(LED_BLUE, HIGH); //  fallo comunicacin
  }
}

// ================= LECTURA QR =================
void readQR() {

  while (Serial1.available()) {

    char c = Serial1.read();

    if (c == '\n') {

      Serial.println("QR: " + qrData);

      sendToNextion(qrData);       // Mostrar QR
      sendLoRa("QR:" + qrData);    // Enviar por LoRa

      qrData = "";

    } else {
      qrData += c;
    }
  }
}

// ================= RECEPCIN LORA =================
void receiveLoRa() {

  int packetSize = LoRa.parsePacket();

  if (packetSize) {

    loraReceived = "";

    while (LoRa.available()) {
      loraReceived += (char)LoRa.read();
    }

    Serial.println("Recibido LoRa: " + loraReceived);

    lastLoRaTime = millis();         // Comunicacin activa
    digitalWrite(LED_BLUE, LOW);     //  OFF

    sendToNextion(loraReceived);     // Mostrar datos
  }
}

// ================= NEXTION INPUT =================
void readNextion() {

  if (Serial2.available()) {

    String cmd = Serial2.readString();

    // Botn "Aceptar"
    if (cmd.indexOf("OK") != -1) {

      Serial.println("Confirmado desde Nextion");

      sendLoRa("CONFIRMADO"); // Enviar confirmacin
    }
  }
}

// ================= ENVO A NEXTION =================
void sendToNextion(String text) {

  Serial2.print("t0.txt=\"");
  Serial2.print(text);
  Serial2.print("\"");

  // Terminacin obligatoria
  Serial2.write(0xFF);
  Serial2.write(0xFF);
  Serial2.write(0xFF);
}

// ================= ENVO LORA =================
void sendLoRa(String data) {

  LoRa.beginPacket();
  LoRa.print(data);
  LoRa.endPacket();

  Serial.println("Enviado LoRa: " + data);
}

// ================= SENSORES =================
void checkSensors() {

  bool s1 = digitalRead(SENSOR1);
  bool s2 = digitalRead(SENSOR2);
  bool s3 = digitalRead(SENSOR3);

  int fails = (!s1) + (!s2) + (!s3);

  if (fails == 0) {
    estadoOK();
  }
  else if (fails < 3) {
    estadoAdvertencia();
  }
  else {
    estadoError();
  }
}

// ================= ESTADO OK =================
void estadoOK() {

  digitalWrite(RELAY_GREEN, HIGH);
  digitalWrite(RELAY_YELLOW, LOW);
  digitalWrite(RELAY_RED, LOW);

  digitalWrite(BUZZER, LOW);

  sendStatusNextion("OK");
}

// ================= ADVERTENCIA =================
void estadoAdvertencia() {

  digitalWrite(RELAY_GREEN, LOW);
  digitalWrite(RELAY_YELLOW, HIGH);
  digitalWrite(RELAY_RED, LOW);

  tone(BUZZER, 1000, 200);

  sendStatusNextion("WARNING");
}

// ================= ERROR =================
void estadoError() {

  digitalWrite(RELAY_GREEN, LOW);
  digitalWrite(RELAY_YELLOW, LOW);
  digitalWrite(RELAY_RED, HIGH);

  tone(BUZZER, 2000);

  sendStatusNextion("ERROR");
}

// ================= RESET =================
void resetOutputs() {

  digitalWrite(RELAY_GREEN, LOW);
  digitalWrite(RELAY_YELLOW, LOW);
  digitalWrite(RELAY_RED, LOW);
  digitalWrite(BUZZER, LOW);
}

// ================= STATUS NEXTION =================
void sendStatusNextion(String status) {

  Serial2.print("t1.txt=\"");
  Serial2.print(status);
  Serial2.print("\"");

  Serial2.write(0xFF);
  Serial2.write(0xFF);
  Serial2.write(0xFF);
}