Complete WS2812B LED ESP8266 Programming Code

#include <ESP8266WiFi.h>
#include <ESP8266mDNS.h>
#include <WiFiUdp.h>
#include <ArduinoOTA.h>
#include <PubSubClient.h>
#include <WS2812FX.h>

// ──────────────────── USER SETTINGS ────────────────────
#define LED_PIN        D4           // Data pin (GPIO2 on NodeMCU)
#define LED_COUNT      30           // Number of LEDs in your strip
#define WIFI_SSID      "YOUR_SSID"
#define WIFI_PASSWORD  "YOUR_PASSWORD"

#define MQTT_SERVER    "192.168.1.100"  // Your MQTT broker IP
#define MQTT_PORT      1883
#define MQTT_USER      ""           // Leave blank if no auth
#define MQTT_PASS      ""           // Leave blank if no auth
#define MQTT_CLIENT_ID "ESP8266_LED"

#define TOPIC_POWER    "home/led/power"
#define TOPIC_EFFECT   "home/led/effect"
#define TOPIC_COLOR    "home/led/color"
#define TOPIC_BRIGHT   "home/led/brightness"
// ────────────────────────────────────────────────────────

WS2812FX ws2812fx = WS2812FX(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);
WiFiClient   espClient;
PubSubClient mqttClient(espClient);
WiFiServer   webServer(80);

bool     powerOn    = true;
uint8_t  effectIdx  = 0;
uint32_t color      = 0xFF0000;  // Default: Red
uint8_t  brightness = 128;

unsigned long lastMQTTReconnectAttempt = 0; // For non-blocking MQTT

void mqttCallback(char* topic, byte* payload, unsigned int len);
void reconnectMQTT();

// ═══════════════════════════════════ SETUP ════════════════════════════════════
void setup() {
  Serial.begin(115200);
  Serial.println("\n=== WS2812B Upgraded Sketch ===");

  // --- LED Init ---
  ws2812fx.init();
  ws2812fx.setBrightness(brightness);
  ws2812fx.setSpeed(100);
  ws2812fx.setMode(effectIdx);
  ws2812fx.setColor(color);
  ws2812fx.start();

  // --- Wi-Fi ---
  WiFi.mode(WIFI_STA);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); }
  Serial.println("\nConnected! IP: " + WiFi.localIP().toString());

  // --- mDNS (access via esp8266-led.local) ---
  if (MDNS.begin("esp8266-led")) Serial.println("mDNS started");

  // --- OTA ---
  ArduinoOTA.setHostname("esp8266-led");
  ArduinoOTA.onStart([]()  { Serial.println("OTA Start"); });
  ArduinoOTA.onEnd([]()    { Serial.println("\nOTA End"); });
  ArduinoOTA.onProgress([](unsigned int p, unsigned int t) {
    Serial.printf("OTA Progress: %u%%\r", (p * 100) / t);
  });
  ArduinoOTA.onError([](ota_error_t e) {
    Serial.printf("OTA Error[%u]: ", e);
    if      (e == OTA_AUTH_ERROR)    Serial.println("Auth Failed");
    else if (e == OTA_BEGIN_ERROR)   Serial.println("Begin Failed");
    else if (e == OTA_CONNECT_ERROR) Serial.println("Connect Failed");
    else if (e == OTA_RECEIVE_ERROR) Serial.println("Receive Failed");
    else if (e == OTA_END_ERROR)     Serial.println("End Failed");
  });
  ArduinoOTA.begin();
  Serial.println("OTA ready");

  // --- MQTT ---
  mqttClient.setServer(MQTT_SERVER, MQTT_PORT);
  mqttClient.setCallback(mqttCallback);

  // --- Web Server ---
  webServer.begin();
  Serial.println("Web server started");
}

// ═══════════════════════════════════ LOOP ════════════════════════════════════
void loop() {
  ArduinoOTA.handle();
  ws2812fx.service();

  // Non-blocking MQTT Reconnect
  if (!mqttClient.connected()) {
    if (millis() - lastMQTTReconnectAttempt > 5000) {
      lastMQTTReconnectAttempt = millis();
      reconnectMQTT();
    }
  } else {
    mqttClient.loop();
  }

  // Web server handler
  WiFiClient client = webServer.available();
  if (client) {
    String request = client.readStringUntil('\r');
    client.flush();

    if      (request.indexOf("/power?state=on")  != -1) { powerOn = true;  ws2812fx.start(); }
    else if (request.indexOf("/power?state=off") != -1) { powerOn = false; ws2812fx.stop();  }
    else if (request.indexOf("/effect?n=")       != -1) {
      effectIdx = request.substring(request.indexOf("n=") + 2).toInt();
      if (effectIdx >= ws2812fx.getModeCount()) effectIdx = 0;
      ws2812fx.setMode(effectIdx);
    }
    else if (request.indexOf("/bright?v=")       != -1) {
      brightness = constrain(request.substring(request.indexOf("v=") + 2).toInt(), 0, 255);
      ws2812fx.setBrightness(brightness);
    }

    // Clean HTML response using Raw String Literal
    String html = R"rawliteral(
      HTTP/1.1 200 OK
      Content-Type: text/html
      Connection: close

      <!DOCTYPE html>
      <html>
      <head>
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <meta charset="utf-8">
        <style>
          body { font-family: Arial, sans-serif; text-align: center; margin: 40px; background: #222; color: #fff;}
          a { display: inline-block; padding: 12px 20px; margin: 8px; background: #007BFF; color: white; text-decoration: none; border-radius: 6px; font-weight: bold;}
          a.off { background: #DC3545; }
          a.on { background: #28A745; }
          h3 { margin-top: 30px; }
        </style>
      </head>
      <body>
        <h2>💡 ESP8266 LED Control</h2>
        
        <h3>Power</h3>
        <a href="/power?state=on" class="on">● ON</a>
        <a href="/power?state=off" class="off">○ OFF</a>
        
        <h3>Effects</h3>
        <a href="/effect?n=0">Static</a>
        <a href="/effect?n=1">Blink</a>
        <a href="/effect?n=8">Rainbow</a>
        <a href="/effect?n=10">Fire</a>
        
        <h3>Brightness</h3>
        <a href="/bright?v=50">Dim</a>
        <a href="/bright?v=128">Medium</a>
        <a href="/bright?v=255">Bright</a>
      </body>
      </html>
    )rawliteral";

    client.print(html);
    delay(1);
    client.stop();
  }
}

// ═══════════════════════════════ MQTT CALLBACK ═══════════════════════════════
void mqttCallback(char* topic, byte* payload, unsigned int len) {
  String msg = "";
  for (unsigned int i = 0; i < len; i++) msg += (char)payload[i];
  Serial.printf("MQTT [%s] -> %s\n", topic, msg.c_str());

  if (strcmp(topic, TOPIC_POWER) == 0) {
    if (msg.equalsIgnoreCase("ON"))  { powerOn = true;  ws2812fx.start(); }
    if (msg.equalsIgnoreCase("OFF")) { powerOn = false; ws2812fx.stop();  }
  }
  else if (strcmp(topic, TOPIC_EFFECT) == 0) {
    effectIdx = msg.toInt();
    if (effectIdx >= ws2812fx.getModeCount()) effectIdx = 0;
    ws2812fx.setMode(effectIdx);
  }
  else if (strcmp(topic, TOPIC_COLOR) == 0) {
    if (msg.startsWith("0x")) msg.remove(0, 2);
    if (msg.startsWith("#"))  msg.remove(0, 1);
    color = strtoul(msg.c_str(), nullptr, 16);
    ws2812fx.setColor(color);
  }
  else if (strcmp(topic, TOPIC_BRIGHT) == 0) {
    brightness = constrain(msg.toInt(), 0, 255);
    ws2812fx.setBrightness(brightness);
  }
}

// ═══════════════════════════════ MQTT RECONNECT ══════════════════════════════
void reconnectMQTT() {
  Serial.print("MQTT connecting...");
  if (mqttClient.connect(MQTT_CLIENT_ID, MQTT_USER, MQTT_PASS)) {
    Serial.println("connected");
    mqttClient.subscribe(TOPIC_POWER);
    mqttClient.subscribe(TOPIC_EFFECT);
    mqttClient.subscribe(TOPIC_COLOR);
    mqttClient.subscribe(TOPIC_BRIGHT);
  } else {
    Serial.printf("failed rc=%d, retry in 5s\n", mqttClient.state());
  }
}