/**
 * AppRegistry - Central registry for app definitions
 *
 * Apps register themselves here with their mount functions and metadata.
 * This is the "catalog" of available apps - not instances.
 */

import { SLOT_IDS } from './types';

/** @type {Map<string, import('./types').AppDefinition>} */
const registry = new Map();

/**
 * Register an app definition
 * @param {import('./types').AppDefinition} definition
 */
export function registerApp(definition) {
  if (!definition.appId) {
    throw new Error('App definition must have appId');
  }
  if (!definition.mountWidget) {
    throw new Error('App definition must have mountWidget function');
  }
  if (registry.has(definition.appId)) {
    console.warn(`App ${definition.appId} already registered, overwriting`);
  }
  registry.set(definition.appId, {
    order: 0,
    defaultSlot: SLOT_IDS.TOP_RIGHT,
    permissions: {},
    ...definition,
  });
}

/**
 * Get an app definition by ID
 * @param {string} appId
 * @returns {import('./types').AppDefinition | undefined}
 */
export function getApp(appId) {
  return registry.get(appId);
}

/**
 * Get all registered apps
 * @returns {import('./types').AppDefinition[]}
 */
export function getAllApps() {
  return Array.from(registry.values());
}

/**
 * Check if an app is registered
 * @param {string} appId
 * @returns {boolean}
 */
export function hasApp(appId) {
  return registry.has(appId);
}

/**
 * Unregister an app (mainly for testing)
 * @param {string} appId
 */
export function unregisterApp(appId) {
  registry.delete(appId);
}

/**
 * Clear all registered apps (mainly for testing)
 */
export function clearRegistry() {
  registry.clear();
}

export default {
  registerApp,
  getApp,
  getAllApps,
  hasApp,
  unregisterApp,
  clearRegistry,
};