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

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

// MQTT broker privat (shiftr.io)
const char* mqtt_server   = "pings-112.cloud.shiftr.io";
const int   mqtt_port     = 1883;
const char* mqtt_user     = "pings-112";     // username broker
const char* mqtt_pass     = "pinsss";        // password/token broker

// Topik
const char* topic_publish = "esp32/pir_sensor";      // publish status PIR
const char* topic_control = "esp32/alarm_control";   // subscribe kontrol alarm

// Pin
#define PIR_PIN    27      
#define LED_ALARM  26    

WiFiClient espClient;
PubSubClient client(espClient);

bool alarmAktif = false;

// Koneksi WiFi
void setup_wifi() {
  Serial.print("Menghubungkan ke WiFi ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi terhubung!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
}

// Callback MQTT
void callback(char* topic, byte* payload, unsigned int length) {
  String msg;
  for (unsigned int i = 0; i < length; i++) {
    msg += (char)payload[i];
  }
  msg.trim();

  Serial.print("Pesan diterima [");
  Serial.print(topic);
  Serial.print("] ");
  Serial.println(msg);

  // Kontrol reset alarm
  if (String(topic) == topic_control) {
    if (msg.equalsIgnoreCase("reset")) {
      digitalWrite(LED_ALARM, LOW);
      alarmAktif = false;
      Serial.println("Alarm direset → LED mati");
    }
  }
}

// Reconnect MQTT
void reconnect() {
  while (!client.connected()) {
    Serial.print("Menghubungkan ke broker MQTT...");
    String clientId = "ESP32Client-" + String(random(0xffff), HEX);

    if (client.connect(clientId.c_str(), mqtt_user, mqtt_pass)) {
      Serial.println("TERHUBUNG!");
      client.subscribe(topic_control);  
      Serial.print("Subscribe ke topik: ");
      Serial.println(topic_control);
    } else {
      Serial.print("Gagal, rc=");
      Serial.print(client.state());
      Serial.println(" coba lagi 2 detik...");
      delay(2000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_ALARM, OUTPUT);

  setup_wifi();
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);
}

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

  int gerakan = digitalRead(PIR_PIN);

  if (gerakan == HIGH && !alarmAktif) {
    digitalWrite(LED_ALARM, HIGH);
    alarmAktif = true;
    client.publish(topic_publish, "Gerakan Terdeteksi!");
    Serial.println("Gerakan Terdeteksi! → LED nyala");
  }

  delay(200);
}