#pragma once

#include "lvgl.h"
#include "esp_err.h"
#include <string>
#include <memory>

// Forward declaration
class InteractionHandler;

/**
 * @brief Base class for all UI applications
 *
 * All UI applications (apps) must inherit from this class.
 * Each app is responsible for managing its own widgets within
 * the provided LVGL container. The UIHandler will manage the
 * lifecycle of apps and event routing.
 */
class UIApp {
public:
  virtual ~UIApp() = default;

  /**
   * @brief Initialize the app with the given container
   *
   * The app should create all its widgets as children of the
   * provided container. The container is already positioned
   * between the header and navigation bar.
   *
   * @param container LVGL container object for this app
   * @param interaction_handler Pointer to interaction handler for keyboard support
   * @return ESP_OK on success, error code otherwise
   */
  virtual esp_err_t init(lv_obj_t* container, InteractionHandler* interaction_handler) = 0;

  /**
   * @brief Deinitialize and clean up app resources
   *
   * The app should delete all widgets and release any resources.
   * The container itself will be handled by UIHandler.
   *
   * @return ESP_OK on success, error code otherwise
   */
  virtual esp_err_t deinit(void) = 0;

  /**
   * @brief Get the display name of this app
   *
   * Used for logging and potentially showing in navigation.
   *
   * @return std::string app name
   */
  virtual std::string get_name(void) const = 0;

  /**
   * @brief Handle back button press
   *
   * Called when the back button is pressed.
   * The app can choose to handle it (e.g., close a dialog)
   * or return false to let UIHandler handle it (e.g., return to main screen).
   *
   * @return true if the event was handled, false otherwise
   */
  virtual bool on_back_button_pressed(void) {
    return false; // default: not handled
  }

protected:
  lv_obj_t* container_ = nullptr;  ///< LVGL container provided by UIHandler
};

class AppDescriptor {
public:
  virtual ~AppDescriptor() = default;
  virtual void draw_icon(lv_obj_t* parent) = 0;

  std::string get_name() const {
    return name_;
  }

  UIApp* get_app_instance() const {
    return app_instance_.get();
  }

protected:
  AppDescriptor(std::string name, std::unique_ptr<UIApp> app_instance)
    : name_(name), app_instance_(std::move(app_instance)) { }

  std::string name_;
  std::unique_ptr<UIApp> app_instance_;
};