import type { ComponentType } from 'react';
import type { PageType } from '@/types/storage';

type PageModule = { default: ComponentType };

let pagesStylesLoaded = false;

function ensurePagesStyles(): Promise<unknown> {
  if (pagesStylesLoaded) {
    return Promise.resolve();
  }
  pagesStylesLoaded = true;
  return import('@/styles/pages.css');
}

export function loadPage(key: PageType): Promise<PageModule> {
  return ensurePagesStyles().then(() => {
    switch (key) {
      case 'timestamp':
        return import('@/config/pageLoaders/timestamp').then((m) => m.default());
      case 'storageCleaner':
        return import('@/config/pageLoaders/storageCleaner').then((m) => m.default());
      case 'qrCode':
        return import('@/config/pageLoaders/qrCode').then((m) => m.default());
      case 'textStatistics':
        return import('@/config/pageLoaders/textStatistics').then((m) => m.default());
      case 'jwt':
        return import('@/config/pageLoaders/jwt').then((m) => m.default());
      case 'jsonTools':
        return import('@/config/pageLoaders/jsonTools').then((m) => m.default());
      case 'base64Converter':
        return import('@/config/pageLoaders/base64Converter').then((m) => m.default());
      case 'rightClickRestorer':
        return import('@/config/pageLoaders/rightClickRestorer').then((m) => m.default());
      case 'testDataGenerator':
        return import('@/config/pageLoaders/testDataGenerator').then((m) => m.default());
      default: {
        const _exhaustive: never = key;
        return Promise.reject(new Error(`Unknown page: ${String(_exhaustive)}`));
      }
    }
  });
}