#include <Adafruit_Sensor.h>
#include <DHT_U.h>
#include <WiFi.h>
#include <PubSubClient.h>
#include <ESP32Servo.h>
#include <FastLED.h>

// ---------------------------
// Pin Definitions
// ---------------------------
#define DHTPIN 12
#define DHTTYPE DHT22

#define LED_PIN_SIMPLE 26  // Normal LED
#define SERVO_PIN 2
#define NEOPIXEL_PIN 4
#define NUM_LEDS 16

// ---------------------------
// Sensor / Devices
// ---------------------------
DHT_Unified dht(DHTPIN, DHTTYPE);
Servo servo;
CRGB leds[NUM_LEDS];

// ---------------------------
// WiFi + MQTT
// ---------------------------
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqttServer = "broker.emqx.io";

WiFiClient espClient;
PubSubClient client(espClient);

unsigned long lastPublish = 0;

// ---------------------------
// Read Temperature Function
// ---------------------------
float getTemperature() {
  sensors_event_t event;
  dht.temperature().getEvent(&event);
  if (isnan(event.temperature)) return -1;
  return event.temperature;
}

// ---------------------------
// Read Humidity Function
// ---------------------------
float getHumidity() {
  sensors_event_t event;
  dht.humidity().getEvent(&event);
  if (isnan(event.relative_humidity)) return -1;
  return event.relative_humidity;
}

// ---------------------------
// WiFi Setup
// ---------------------------
void setup_wifi() {
  Serial.print("Connecting to WiFi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(250);
    Serial.print(".");
  }
  Serial.println("\nWiFi Connected!");
}

// ---------------------------
// MQTT Reconnect
// ---------------------------
void reconnect() {
  while (!client.connected()) {
    Serial.print("MQTT connecting... ");
    if (client.connect("ESP32-Dashboard-Device")) {
      Serial.println("connected");

      client.subscribe("lights");
      client.subscribe("servo");
      client.subscribe("lights/neopixel");

    } else {
      Serial.print("Failed (rc=");
      Serial.print(client.state());
      Serial.println("). Retry in 5 sec...");
      delay(5000);
    }
  }
}

// ---------------------------
// MQTT Callback
// ---------------------------
void callback(char* topic, byte* payload, unsigned int len) {
  String data = "";
  for (int i = 0; i < len; i++) data += (char)payload[i];

  Serial.print("Topic: ");
  Serial.println(topic);
  Serial.print("Payload: ");
  Serial.println(data);

  // ---------------------------
  // LED ON/OFF
  // ---------------------------
  if (String(topic) == "lights") {
    if (data == "ON") digitalWrite(LED_PIN_SIMPLE, HIGH);
    else digitalWrite(LED_PIN_SIMPLE, LOW);
  }

  // ---------------------------
  // Servo Control
  // ---------------------------
  if (String(topic) == "servo") {
    int degree = data.toInt();
    servo.write(degree);
    Serial.printf("Servo → %d degrees\n", degree);
  }

  // ---------------------------
  // RGB Parsing for Neopixel
  // Format: "R,G,B"
  // ---------------------------
  if (String(topic) == "lights/neopixel") {
    int r, g, b;
    sscanf(data.c_str(), "%d,%d,%d", &r, &g, &b);

    Serial.printf("Neopixel → R:%d G:%d B:%d\n", r, g, b);

    fill_solid(leds, NUM_LEDS, CRGB(r, g, b));
    FastLED.show();
  }
}

// ---------------------------
// Setup
// ---------------------------
void setup() {
  Serial.begin(115200);

  // Sensors
  dht.begin();

  // Simple LED
  pinMode(LED_PIN_SIMPLE, OUTPUT);
  digitalWrite(LED_PIN_SIMPLE, LOW);

  // Servo
  servo.attach(SERVO_PIN);
  servo.write(0);

  // Neopixel
  FastLED.addLeds<WS2812, NEOPIXEL_PIN, GRB>(leds, NUM_LEDS);

  // WiFi & MQTT
  setup_wifi();
  client.setServer(mqttServer, 1883);
  client.setCallback(callback);
}

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

  unsigned long now = millis();
  if (now - lastPublish > 1000) {  // every 1 second
    lastPublish = now;

    float t = getTemperature();
    float h = getHumidity();

    Serial.printf("Temp: %.2f | Hum: %.2f\n", t, h);

    client.publish("temperature", String(t).c_str());
    client.publish("humidity", String(h).c_str());
  }
}