/**
 * @file mqttClient.hpp
 * @author Gustice
 * @brief Wrapper class for TCP/IP based MQTT APIs
 *
 * @copyright Copyright (c) 2024
 */
#pragma once

#include "esp_event.h"
#include "esp_system.h"
#include "mqtt_client.h"
#include <functional>
#include <string>
#include <string_view>

/**
 * @brief MqttClient wrapper (Singleton)
 */
class MqttClient {
  public:
    /// @brief Init and mount file system
    /// @param broker URI to web MQTT broker server
  static MqttClient &init(std::string broker, std::string prefix);
    void addSubscription(std::string topic, std::function<void(std::string)> call);
    void publish(std::string topic, std::string data);
    void start();
    bool isRunning() { return _state != State::Init; }

    /// @brief Get instance, ensure initialization
    /// @param broker URI to web MQTT broker server
    /// @returnb
    static MqttClient &getInstance();

    // Disable move and assignment
    MqttClient(MqttClient &other) = delete;
    void operator=(const MqttClient &) = delete;

  // protected:
     MqttClient(std::string broker, std::string pefix);
     ~MqttClient();

  private:
    enum class State {
        Init,
        Started,
        Disconnected,
        Connected
    };
    struct Subscription {
        std::string topic;
        std::function<void(std::string)> callback;
        bool active{};
        int id{};
    };

    std::string _broker;
    std::string _prefix;
    State _state{};
    static MqttClient *_instance;
    esp_mqtt_client_handle_t _client;
    std::vector<Subscription> _subscriptions;

    static void eventHandler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data);
};