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

// Pins
#define LDR_PIN 34       // Analog LDR pin
#define PIR_PIN 27       // Digital PIR pin
#define LED_PIN 5        // PWM LED pin

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

// HiveMQ Cloud
const char* mqtt_server = "2f77695c0fe64529822ff2e4579f5844.s1.eu.hivemq.cloud";  
const int mqtt_port = 8883;   // TLS
const char* mqtt_user = "esp32user";
const char* mqtt_pass = "Smart1234";

// Root CA Certificate
const char* root_ca = 
"-----BEGIN CERTIFICATE-----\n"
"MIIFazCCA1OgAwIBAgIRAIIQz7DSQONZRGPgu2OCiwAwDQYJKoZIhvcNAQELBQAw\n"
"TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh\n"
"cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMTUwNjA0MTEwNDM4\n"
"WhcNMzUwNjA0MTEwNDM4WjBPMQswCQYDVQQGEwJVUzEpMCcGA1UEChMgSW50ZXJu\n"
"ZXQgU2VjdXJpdHkgUmVzZWFyY2ggR3JvdXAxFTATBgNVBAMTDElTUkcgUm9vdCBY\n"
"MTCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAK3oJHP0FDfzm54rVygc\n"
"h77ct984kIxuPOZXoHj3dcKi/vVqbvYATyjb3miGbESTtrFj/RQSa78f0uoxmyF+\n"
"0TM8ukj13Xnfs7j/EvEhmkvBioZxaUpmZmyPfjxwv60pIgbz5MDmgK7iS4+3mX6U\n"
"A5/TR5d8mUgjU+g4rk8Kb4Mu0UlXjIB0ttov0DiNewNwIRt18jA8+o+u3dpjq+sW\n"
"T8KOEUt+zwvo/7V3LvSye0rgTBIlDHCNAymg4VMk7BPZ7hm/ELNKjD+Jo2FR3qyH\n"
"B5T0Y3HsLuJvW5iB4YlcNHlsdu87kGJ55tukmi8mxdAQ4Q7e2RCOFvu396j3x+UC\n"
"B5iPNgiV5+I3lg02dZ77DnKxHZu8A/lJBdiB3QW0KtZB6awBdpUKD9jf1b0SHzUv\n"
"KBds0pjBqAlkd25HN7rOrFleaJ1/ctaJxQZBKT5ZPt0m9STJEadao0xAH0ahmbWn\n"
"OlFuhjuefXKnEgV4We0+UXgVCwOPjdAvBbI+e0ocS3MFEvzG6uBQE3xDk3SzynTn\n"
"jh8BCNAw1FtxNrQHusEwMFxIt4I7mKZ9YIqioymCzLq9gwQbooMDQaHWBfEbwrbw\n"
"qHyGO0aoSCqI3Haadr8faqU9GY/rOPNk3sgrDQoo//fb4hVC1CLQJ13hef4Y53CI\n"
"rU7m2Ys6xt0nUW7/vGT1M0NPAgMBAAGjQjBAMA4GA1UdDwEB/wQEAwIBBjAPBgNV\n"
"HRMBAf8EBTADAQH/MB0GA1UdDgQWBBR5tFnme7bl5AFzgAiIyBpY9umbbjANBgkq\n"
"hkiG9w0BAQsFAAOCAgEAVR9YqbyyqFDQDLHYGmkgJykIrGF1XIpu+ILlaS/V9lZL\n"
"ubhzEFnTIZd+50xx+7LSYK05qAvqFyFWhfFQDlnrzuBZ6brJFe+GnY+EgPbk6ZGQ\n"
"3BebYhtF8GaV0nxvwuo77x/Py9auJ/GpsMiu/X1+mvoiBOv/2X/qkSsisRcOj/KK\n"
"NFtY2PwByVS5uCbMiogziUwthDyC3+6WVwW6LLv3xLfHTjuCvjHIInNzktHCgKQ5\n"
"ORAzI4JMPJ+GslWYHb4phowim57iaztXOoJwTdwJx4nLCgdNbOhdjsnvzqvHu7Ur\n"
"TkXWStAmzOVyyghqpZXjFaH3pO3JLF+l+/+sKAIuvtd7u+Nxe5AW0wdeRlN8NwdC\n"
"jNPElpzVmbUq4JUagEiuTDkHzsxHpFKVK7q4+63SM1N95R1NbdWhscdCb+ZAJzVc\n"
"oyi3B43njTOQ5yOf+1CceWxG1bQVs5ZufpsMljq4Ui0/1lvh+wjChP4kqKOJ2qxq\n"
"4RgqsahDYVvTH9w7jXbyLeiNdd8XM2w9U/t7y0Ff/9yi0GE44Za4rF2LN9d11TPA\n"
"mRGunUHBcnWEvgJBQl9nJEiU0Zsnvgc/ubhPgXRR4Xq37Z0j4r7g1SgEEzwxA57d\n"
"emyPxgcYxn/eR44/KJ4EBs+lVDR3veyJm+kXQ99b21/+jh5Xos1AnX5iItreGCc=\n"
"-----END CERTIFICATE-----\n";

WiFiClientSecure espClient;
PubSubClient client(espClient);

// Setup WiFi
void setup_wifi() {
  Serial.print("Connecting to WiFi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(200);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected.");
}

// MQTT reconnect
void reconnect() {
  while (!client.connected()) {
    Serial.print("Connecting to MQTT securely...");
    if (client.connect("ESP32SecureClient", mqtt_user, mqtt_pass)) {
      Serial.println("connected!");
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      delay(5000);
    }
  }
}

// Rule-based Edge AI for LED brightness
int getBrightness(int ldrValue, int pirValue) {
  // Map LDR analog value (0–4095) to PWM (255=bright, 0=off)
  int brightness = map(ldrValue, 0, 4095, 255, 0);

  // Boost brightness if motion detected
  if (pirValue == HIGH) brightness = min(255, brightness + 50);

  return brightness;
}

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

  pinMode(LDR_PIN, INPUT);
  pinMode(PIR_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);

  setup_wifi();
  espClient.setCACert(root_ca);
  client.setServer(mqtt_server, mqtt_port);
}

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

  // Read sensors
  int ldrValue = analogRead(LDR_PIN);      // 0–4095
  int pirValue = digitalRead(PIR_PIN);     // 0 or 1

  // Compute LED brightness using rule-based Edge AI
  int brightness = getBrightness(ldrValue, pirValue);
  analogWrite(LED_PIN, brightness);

  // Publish sensor data
  client.publish("street/light/ldr", String(ldrValue).c_str());
  client.publish("street/light/pir", String(pirValue).c_str());
  client.publish("street/light/brightness", String(brightness).c_str());

  // Debug output
  Serial.print("LDR: "); Serial.print(ldrValue);
  Serial.print(" | PIR: "); Serial.print(pirValue);
  Serial.print(" | LED PWM: "); Serial.println(brightness);

  delay(1000);
}