Widget Manager

/**
 * Interface for widget managers that handle model and view lifecycle
 */
interface IWidgetManager {
  /**
   * Get a model by its unique identifier
   * @param model_id - Unique model identifier
   * @returns Promise that resolves to the widget model, or undefined if not found
   */
  get_model(model_id: string): Promise<WidgetModel>;

  /**
   * Check if a model is registered with the manager
   * @param model_id - Model identifier to check
   * @returns True if model exists, false otherwise
   */
  has_model(model_id: string): boolean;

  /**
   * Register a model instance with the manager
   * @param model_id - Unique identifier for the model
   * @param modelPromise - Promise that resolves to the model instance
   */
  register_model(model_id: string, modelPromise: Promise<WidgetModel>): void;

  /**
   * Create a new widget with communication channel
   * @param options - Widget creation options (includes view information)
   * @param serialized_state - Optional initial state for the widget
   * @returns Promise that resolves to the created widget model
   */
  new_widget(options: IWidgetOptions, serialized_state?: JSONObject): Promise<WidgetModel>;

  /**
   * Create a new model instance
   * @param options - Model creation options
   * @param serialized_state - Optional initial state for the model
   * @returns Promise that resolves to the created model
   */
  new_model(options: IModelOptions, serialized_state?: JSONObject): Promise<WidgetModel>;

  /**
   * Create a view for a given model
   * @param model - Widget model to create view for
   * @param options - View creation options
   * @returns Promise that resolves to the created view
   */
  create_view<VT extends DOMWidgetView = DOMWidgetView>(
    model: DOMWidgetModel,
    options?: unknown
  ): Promise<VT>;
  create_view<VT extends WidgetView = WidgetView>(
    model: WidgetModel,
    options?: unknown
  ): Promise<VT>;

  /**
   * Get callback handlers for a specific view
   * @param view - View to get callbacks for (optional)
   * @returns Callback configuration object
   */
  callbacks(view?: WidgetView): ICallbacks;

  /**
   * Resolve a URL relative to the current notebook location
   * @param url - URL to resolve
   * @returns Promise that resolves to the absolute URL
   */
  resolveUrl(url: string): Promise<string>;

  /**
   * Sanitize HTML content for inline display
   * @param s - HTML string to sanitize
   * @returns Sanitized HTML string
   */
  inline_sanitize(s: string): string;
}

// Get existing model
const model = await widgetManager.get_model('widget-123');

// Check if model exists
if (widgetManager.has_model('widget-123')) {
  // Model is available
}

// Create new widget with comm
const widget = await widgetManager.new_widget({
  model_name: 'IntSlider',
  model_module: '@jupyter-widgets/controls',
  model_module_version: '1.0.0',
  view_name: 'IntSliderView',
  view_module: '@jupyter-widgets/controls',
  view_module_version: '1.0.0'
}, { value: 50, min: 0, max: 100 });

// Create view for model
const view = await widgetManager.create_view(model);

/**
 * Options for creating widget models
 */
interface IModelOptions {
  /**
   * Target name of the widget model class to create
   */
  model_name: string;

  /**
   * Module name containing the widget model class
   */
  model_module: string;

  /**
   * Semver version requirement for the model module
   */
  model_module_version: string;

  /**
   * Target name of the widget view class (optional for model-only creation)
   */
  view_name?: string | null;

  /**
   * Module name containing the widget view class
   */
  view_module?: string | null;

  /**
   * Semver version requirement for the view module
   */
  view_module_version?: string;

  /**
   * Communication object for kernel interaction
   */
  comm?: any;

  /**
   * Unique identifier for the model (auto-generated if not provided)
   */
  model_id?: string;
}

/**
 * Options for creating connected widgets (requires view information)
 */
interface IWidgetOptions extends IModelOptions {
  /**
   * Target name of the widget model class to create (required)
   */
  model_name: string;

  /**
   * Module name containing the widget model class (required)
   */
  model_module: string;

  /**
   * Semver version requirement for the model module (required)
   */
  model_module_version: string;

  /**
   * Target name of the widget view class (required for widgets)
   */
  view_name: string | null;

  /**
   * Module name containing the widget view class (required for widgets)
   */
  view_module: string | null;

  /**
   * Semver version requirement for the view module (required)
   */
  view_module_version: string;

  /**
   * Communication object for kernel interaction
   */
  comm?: IClassicComm;

  /**
   * Unique identifier for the model
   */
  model_id?: string;
}

// Create model-only (no view)
const modelOptions: IModelOptions = {
  model_name: 'DataModel',
  model_module: 'my-widgets',
  model_module_version: '1.0.0',
  model_id: 'unique-data-model'
};
const dataModel = await widgetManager.new_model(modelOptions);

// Create complete widget
const widgetOptions: IWidgetOptions = {
  model_name: 'SliderModel',
  model_module: '@jupyter-widgets/controls',
  model_module_version: '1.0.0',
  view_name: 'SliderView',
  view_module: '@jupyter-widgets/controls',
  view_module_version: '1.0.0'
};
const slider = await widgetManager.new_widget(widgetOptions, { value: 42 });

// Manager initialization
class MyWidgetManager implements IWidgetManager {
  private models: Map<string, Promise<WidgetModel>> = new Map();
  
  async get_model(model_id: string): Promise<WidgetModel> {
    const modelPromise = this.models.get(model_id);
    if (!modelPromise) {
      throw new Error(`Model ${model_id} not found`);
    }
    return modelPromise;
  }
  
  has_model(model_id: string): boolean {
    return this.models.has(model_id);
  }
  
  register_model(model_id: string, modelPromise: Promise<WidgetModel>): void {
    this.models.set(model_id, modelPromise);
  }
  
  async new_model(options: IModelOptions, state?: JSONObject): Promise<WidgetModel> {
    // Load model class
    const ModelClass = await this.loadModelClass(options.model_module, options.model_name);
    
    // Create instance
    const model = new ModelClass(state || {}, {
      model_id: options.model_id || this.generateId(),
      widget_manager: this,
      comm: options.comm
    });
    
    // Register and return
    this.register_model(model.model_id, Promise.resolve(model));
    return model;
  }
  
  // Additional implementation methods...
}

// Create views with proper error handling
async createWidgetView(model: WidgetModel): Promise<WidgetView> {
  try {
    const view = await this.widgetManager.create_view(model, {
      parent: this.parentView
    });
    
    // Setup view lifecycle
    view.displayed.then(() => {
      console.log('View displayed');
    });
    
    return view;
  } catch (error) {
    console.error('Failed to create view:', error);
    throw error;
  }
}

// Manage view collections
const views = await Promise.all(
  models.map(model => this.widgetManager.create_view(model))
);

// Register models with manager
const registerWidget = async (modelClass: typeof WidgetModel, initialState: any) => {
  const model = new modelClass(initialState, {
    model_id: generateUniqueId(),
    widget_manager: widgetManager
  });
  
  widgetManager.register_model(model.model_id, Promise.resolve(model));
  return model;
};

// Lookup and use existing models
const findOrCreateModel = async (modelId: string, fallbackOptions: IModelOptions) => {
  if (widgetManager.has_model(modelId)) {
    return await widgetManager.get_model(modelId);
  } else {
    return await widgetManager.new_model({
      ...fallbackOptions,
      model_id: modelId
    });
  }
};

// Setup callbacks for widget communication
const setupWidgetCallbacks = (view: WidgetView): ICallbacks => {
  return widgetManager.callbacks(view);
};

// Handle model creation with communication
const createConnectedWidget = async (comm: IClassicComm, options: IWidgetOptions) => {
  const widget = await widgetManager.new_widget({
    ...options,
    comm: comm,
    model_id: comm.comm_id
  });
  
  // Widget is now connected to kernel
  return widget;
};