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

// PIN CONFIGURATION
#define RED_LED_PIN 13     // Red LED on GPIO13
#define DHT_PIN 15         // DHT22 on GPIO15
#define DHTTYPE DHT22

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

// MQTT
const char* mqtt_server = "broker.hivemq.com";
const int mqtt_port = 1883;
const char* mqtt_topic_control = "wokwi/alexa/control";
const char* mqtt_topic_status = "wokwi/alexa/status";

WiFiClient espClient;
PubSubClient client(espClient);
DHT dht(DHT_PIN, DHTTYPE);

void setup_wifi() {
  Serial.println("\n🔌 Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\n✅ WiFi Connected!");
  Serial.print("📡 IP: ");
  Serial.println(WiFi.localIP());
}

void callback(char* topic, byte* payload, unsigned int length) {
  Serial.println("\n========================================");
  Serial.println("📨 MESSAGE RECEIVED!");
  
  String message = "";
  for (unsigned int i = 0; i < length; i++) {
    message += (char)payload[i];
  }
  
  Serial.print("Command: ");
  Serial.println(message);
  Serial.println("========================================");
  
  // Turn LED ON
  if (message == "ON" || message == "RED_ON" || message == "LIGHT_ON") {
    digitalWrite(RED_LED_PIN, HIGH);
    Serial.println("🔴 RED LED → ON");
    client.publish(mqtt_topic_status, "Red light is ON");
  }
  
  // Turn LED OFF
  else if (message == "OFF" || message == "RED_OFF" || message == "LIGHT_OFF") {
    digitalWrite(RED_LED_PIN, LOW);
    Serial.println("⚫ RED LED → OFF");
    client.publish(mqtt_topic_status, "Red light is OFF");
  }
  
  // Get Temperature
  else if (message == "TEMP" || message == "GET_TEMP" || message == "TEMPERATURE") {
    float temp = dht.readTemperature();
    float humidity = dht.readHumidity();
    
    if (!isnan(temp) && !isnan(humidity)) {
      char msg[100];
      sprintf(msg, "Temperature: %.1f°C, Humidity: %.1f%%", temp, humidity);
      Serial.println("🌡️ " + String(msg));
      client.publish(mqtt_topic_status, msg);
    } else {
      Serial.println("❌ Sensor error!");
      client.publish(mqtt_topic_status, "Sensor error");
    }
  }
  
  else {
    Serial.println("⚠️ Unknown: " + message);
  }
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("🔄 Connecting to MQTT...");
    String clientId = "Wokwi-" + String(random(0xffff), HEX);
    
    if (client.connect(clientId.c_str())) {
      Serial.println(" ✅ Connected!");
      client.subscribe(mqtt_topic_control);
      Serial.println("📡 Subscribed to: " + String(mqtt_topic_control));
    } else {
      Serial.print(" ❌ Failed, rc=");
      Serial.println(client.state());
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  delay(1000);
  
  Serial.println("\n🚀 WOKWI ALEXA CONTROLLER");
  Serial.println("Red LED: GPIO13");
  Serial.println("DHT22: GPIO15");
  
  pinMode(RED_LED_PIN, OUTPUT);
  digitalWrite(RED_LED_PIN, LOW);
  
  dht.begin();
  setup_wifi();
  
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);
  
  Serial.println("\n✅ READY! Waiting for commands...\n");
}

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