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

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

const char* mqtt_server = "io.adafruit.com";
const char* aio_username = "sriharish05";  // 
const char* aio_key = "aio_zQXf560JS1EuxpauUw8iDWAMzNdA"; 

#define LOCK1 16
#define LOCK2 17
#define LOCK3 18

WiFiClient espClient;
PubSubClient client(espClient);

// Define MQTT Topics for the Group
String lock_command_topic = String(aio_username) + "/feeds/locks.command";
String lock_status_topic = String(aio_username) + "/feeds/locks.status";
String lock_log_topic = String(aio_username) + "/feeds/locks.log";

void callback(char* topic, byte* payload, unsigned int length) {
    
    String message = "";
    for (int i = 0; i < length; i++) {
        message += (char)payload[i];
    }
    Serial.println("Received MQTT Message: " + message);

    int commaIndex = message.indexOf(',');
    if (commaIndex == -1) {
        Serial.println("Invalid message format!");
        return;
    }

    int lock_id = message.substring(0, commaIndex).toInt();
    String action = message.substring(commaIndex + 1);

    int pin = 0;
    if (lock_id == 1) pin = LOCK1;
    else if (lock_id == 2) pin = LOCK2;
    else if (lock_id == 3) pin = LOCK3;

    if (pin != 0) {
        if (action == "lock") {
            digitalWrite(pin, HIGH);
        } else if (action == "unlock") {
            digitalWrite(pin, LOW);
        }
        sendMQTTResponse(lock_id,action+"ing", "success");
    } else {
        sendMQTTResponse(lock_id,action+"ing", "failure");
    }
}

void sendMQTTResponse(int lock_id, String act ,String status) {
    String message = String(lock_id) + "," +act+","+status;
    client.publish(lock_status_topic.c_str(), message.c_str());
    Serial.println("Published: " + message);

    // Log the action
    char logMessage[100];
    sprintf(logMessage, "Lock %d -> Action: %s | Status: %s", lock_id, act, status);
    client.publish(lock_log_topic, logMessage);
    Serial.print("Logged: ");
    Serial.println(logMessage);
}

void reconnect() {
    while (!client.connected()) {
        Serial.print("Reconnecting to MQTT...");
        if (client.connect("ESP32_Client", aio_username, aio_key)) {
            Serial.println("Connected!");
            client.subscribe(lock_command_topic.c_str());
        } else {
            Serial.println("Failed. Retrying...");
            delay(2000);
        }
    }
}

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

    pinMode(LOCK1, OUTPUT);
    pinMode(LOCK2, OUTPUT);
    pinMode(LOCK3, OUTPUT);

    WiFi.mode(WIFI_STA);
    WiFi.begin(ssid, password);
    Serial.println("Connecting to WiFi.");
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("Connected to WiFi");

    client.setServer(mqtt_server, 1883);
    client.setCallback(callback);
    reconnect();
}

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