import { route } from 'quasar/wrappers';
import {
  createMemoryHistory,
  createRouter,
  createWebHashHistory,
  createWebHistory,
} from 'vue-router';

import routes from './routes';

/*
 * If not building with SSR mode, you can
 * directly export the Router instantiation;
 *
 * The function below can be async too; either use
 * async/await or return a Promise which resolves
 * with the Router instance.
 */

/**
 * Set by the [vtables] embed document (includes/Classes/Embed.php) — present
 * only inside the public iframe, never in wp-admin.
 */
interface EmbedContext {
  tableId: number;
}

/** Classes\Embed::QUERY_VAR — the plain-permalinks form of the embed URL. */
const EMBED_QUERY_VAR = 'vtables_embed';

function parseTableId(raw: unknown): EmbedContext | undefined {
  const tableId = Number(raw);

  return Number.isInteger(tableId) && tableId > 0 ? { tableId } : undefined;
}

/**
 * The table id, from whichever of the embed document's three carriers survived.
 *
 * The inline global alone was a single point of failure. That document is now
 * emitted by WordPress rather than served as a static file, so page optimisers
 * (WP Rocket, LiteSpeed, Autoptimize) get to rewrite it, and deferring or moving
 * inline <script> blocks is routine for them — with the global gone the router
 * falls through to '/' and renders the admin table list inside a visitor's page.
 * Embed.php asks them to keep their hands off, and these fallbacks cover the
 * case where something rewrites the document anyway.
 */
function getEmbedContext(): EmbedContext | undefined {
  if (typeof window === 'undefined') {
    return undefined;
  }

  const { __vtablesEmbed: fromGlobal } = window as unknown as {
    __vtablesEmbed?: EmbedContext;
  };
  const { search, pathname } = window.location;

  return (
    parseTableId(fromGlobal?.tableId) ||
    parseTableId(document.getElementById('q-app')?.dataset.vtablesTable) ||
    parseTableId(new URLSearchParams(search).get(EMBED_QUERY_VAR)) ||
    // Default slug only — a site that filters 'vtables_embed_slug' is
    // already covered by the two carriers above.
    parseTableId(pathname.match(/\/vtables-embed\/(\d+)\/?$/)?.[1])
  );
}

export default route(function (/* { store, ssrContext } */) {
  const embed = getEmbedContext();

  // In the public iframe the route comes from the embed document, not from the
  // URL: a memory history keeps the address at /vtables-embed/{id}/ with no
  // hash, and stops in-frame navigation from pushing entries onto the top
  // window's session history (an iframe hash change is a real history entry,
  // which used to hijack the visitor's Back button). Everything else — wp-admin
  // and the legacy dist/spa/#/front-table/{id} entry point — keeps the
  // configured hash history.
  const createHistory = process.env.SERVER || embed
    ? createMemoryHistory
    : (process.env.VUE_ROUTER_MODE === 'history' ? createWebHistory : createWebHashHistory);

  // Leave this as is and make changes in quasar.conf.js instead!
  // quasar.conf.js -> build -> vueRouterMode
  // quasar.conf.js -> build -> publicPath
  const history = createHistory(process.env.VUE_ROUTER_BASE);

  // A memory history starts at '/', so seed it here — before createRouter.
  // Router.replace() after the fact does not work: vue-router's install() runs
  // push(routerHistory.location) on mount, which would override the pending
  // navigation and land on the index page (in the public iframe that means the
  // admin table list, firing an admin-ajax call with no nonce).
  if (embed) {
    history.replace(`/front-table/${embed.tableId}`);
  }

  const Router = createRouter({
    scrollBehavior: () => ({ left: 0, top: 0 }),
    routes,
    history,
  });

  return Router;
});