/**
 * @file newBuildReload.ts
 * @description Reloads the tab onto the new UI build after the server was
 * updated. Every update — the dashboard's own Update button in any tab,
 * `/agenthub-update`, a restart onto a newer plugin — drops the WebSocket; when
 * it comes back, `GET /api/health` names the server's version, and a version
 * other than this bundle's `__APP_VERSION__` means the page is stale. At most
 * one reload per version (sessionStorage), so a server whose UI build failed
 * cannot make the tab reload on every reconnect.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { eventBus } from "./eventBus";

const KEY = "agenthub.reloadedFor";

export function reloadOnNewBuild({
  bundle = __APP_VERSION__,
  health = () => fetch("/api/health").then((r) => r.json() as Promise<{ version?: string }>),
  reload = () => window.location.reload(),
  storage = window.sessionStorage,
}: {
  bundle?: string;
  health?: () => Promise<{ version?: string }>;
  reload?: () => void;
  storage?: Pick<Storage, "getItem" | "setItem">;
} = {}): () => void {
  let wasDown = false;
  return eventBus.onConnection((up) => {
    if (!up) {
      wasDown = true;
      return;
    }
    if (!wasDown) return;
    wasDown = false;
    health()
      .then(({ version }) => {
        if (!version || version === bundle || storage.getItem(KEY) === version) return;
        storage.setItem(KEY, version);
        reload();
      })
      .catch(() => {
        /* the next reconnect asks again */
      });
  });
}