/*
  NovaGuard Firmware V1
  LoRa RX · Departamento · Cliente 103

  ESP32 + LoRa RX + Buzzer + WiFi HTTP Worker
  Opcional OLED.

  Función:
  - Recibe paquetes desde el TX del sótano.
  - Muestra por Serial.
  - Activa buzzer si detecta "alarma":true.
  - Reenvía el JSON recibido a Cloudflare Worker / Firestore.

  IMPORTANTE:
  - Ajustar pines LoRa según placa real.
  - Para Heltec ESP32 S3 LoRa SX1262 puede requerir RadioLib/Heltec, no LoRa clásica.
*/

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

// Pines LoRa genéricos. Ajustar según placa.
#define LORA_SS      18
#define LORA_RST     14
#define LORA_DIO0    26
#define LORA_FREQ    433E6

#define PIN_BUZZER   25

const char* WIFI_SSID = "TU_WIFI";
const char* WIFI_PASS = "TU_PASSWORD";
const char* ENDPOINT  = "https://tu-worker-novaguard.workers.dev/ingest-lora";

const char* CLIENTE_ID = "103";
const char* EQUIPO_ID  = "depto_rx_103";
const char* UBICACION  = "Departamento Garcia";

unsigned long lastPacketAt = 0;
const unsigned long LINK_TIMEOUT = 60000;

void conectarWiFi(){
  if(WiFi.status() == WL_CONNECTED) return;

  Serial.print("Conectando WiFi");
  WiFi.begin(WIFI_SSID, WIFI_PASS);

  unsigned long start = millis();
  while(WiFi.status() != WL_CONNECTED && millis() - start < 15000){
    delay(500);
    Serial.print(".");
  }

  Serial.println();
  if(WiFi.status() == WL_CONNECTED){
    Serial.print("WiFi OK · IP: ");
    Serial.println(WiFi.localIP());
  }else{
    Serial.println("WiFi NO conectado");
  }
}

void iniciarLoRa(){
  LoRa.setPins(LORA_SS, LORA_RST, LORA_DIO0);

  if(!LoRa.begin(LORA_FREQ)){
    Serial.println("ERROR: no inicia LoRa RX");
    while(true){
      digitalWrite(PIN_BUZZER, HIGH);
      delay(150);
      digitalWrite(PIN_BUZZER, LOW);
      delay(850);
    }
  }

  LoRa.setSpreadingFactor(10);
  LoRa.setSignalBandwidth(125E3);
  LoRa.setCodingRate4(5);
  LoRa.enableCrc();

  Serial.println("LoRa RX listo");
}

void enviarWorker(String payload){
  if(WiFi.status() != WL_CONNECTED){
    conectarWiFi();
    if(WiFi.status() != WL_CONNECTED) return;
  }

  String wrapped = "{";
  wrapped += "\"cliente_id\":\"" + String(CLIENTE_ID) + "\",";
  wrapped += "\"equipo_id\":\"" + String(EQUIPO_ID) + "\",";
  wrapped += "\"ubicacion\":\"" + String(UBICACION) + "\",";
  wrapped += "\"tipo\":\"LORA_RX_DEPTO\",";
  wrapped += "\"rssi\":" + String(LoRa.packetRssi()) + ",";
  wrapped += "\"snr\":" + String(LoRa.packetSnr()) + ",";
  wrapped += "\"payload\":" + payload;
  wrapped += "}";

  HTTPClient http;
  http.begin(ENDPOINT);
  http.addHeader("Content-Type", "application/json");

  int code = http.POST(wrapped);
  Serial.print("HTTP Worker: ");
  Serial.println(code);

  if(code > 0){
    Serial.println(http.getString());
  }

  http.end();
}

void setup(){
  Serial.begin(115200);
  delay(800);

  pinMode(PIN_BUZZER, OUTPUT);
  digitalWrite(PIN_BUZZER, LOW);

  conectarWiFi();
  iniciarLoRa();

  Serial.println("NovaGuard LoRa RX Departamento listo");
}

void loop(){
  int packetSize = LoRa.parsePacket();

  if(packetSize){
    String payload = "";

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

    lastPacketAt = millis();

    int rssi = LoRa.packetRssi();
    float snr = LoRa.packetSnr();

    Serial.println("RX LoRa:");
    Serial.println(payload);
    Serial.print("RSSI: ");
    Serial.print(rssi);
    Serial.print(" · SNR: ");
    Serial.println(snr);

    bool alarma = payload.indexOf("\"alarma\":true") >= 0;
    digitalWrite(PIN_BUZZER, alarma ? HIGH : LOW);

    enviarWorker(payload);
  }

  if(millis() - lastPacketAt > LINK_TIMEOUT && lastPacketAt > 0){
    // Aviso de posible pérdida de enlace: dos pitidos cortos cada ciclo de timeout.
    digitalWrite(PIN_BUZZER, HIGH);
    delay(120);
    digitalWrite(PIN_BUZZER, LOW);
    delay(120);
    digitalWrite(PIN_BUZZER, HIGH);
    delay(120);
    digitalWrite(PIN_BUZZER, LOW);

    lastPacketAt = millis();
    Serial.println("Advertencia: sin paquetes LoRa recientes");
  }

  delay(50);
}