// Verify the orphan-rescue fallback: if the current-visit pointer is lost
// (storage.session cleared, simulating SW eviction / restart with a stable tab),
// a follow-on click should still attach to the tab's last page via IndexedDB.
//
//   node scripts/orphan-probe.mjs   (after `npm run build`)

import { chromium } from "playwright";
import { mkdtempSync } from "node:fs";
import { tmpdir } from "node:os";
import { fileURLToPath } from "node:url";
import { dirname, resolve } from "node:path";

const DIST = resolve(dirname(fileURLToPath(import.meta.url)), "../dist");
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

const context = await chromium.launchPersistentContext(mkdtempSync(resolve(tmpdir(), "hg-")), {
  headless: false,
  args: [`--disable-extensions-except=${DIST}`, `--load-extension=${DIST}`],
});

try {
  let [sw] = context.serviceWorkers();
  if (!sw) sw = await context.waitForEvent("serviceworker", { timeout: 10_000 });
  const extId = new URL(sw.url()).host;

  const page = await context.newPage();
  await page.goto("https://en.wikipedia.org/wiki/Main_Page", { waitUntil: "load" });
  await sleep(1500);
  await page.goto("https://en.wikipedia.org/wiki/Istanbul", { waitUntil: "load" });
  await sleep(1500);

  // Simulate a lost current-visit pointer (eviction / browser restart).
  const wiper = await context.newPage();
  await wiper.goto(`chrome-extension://${extId}/viewer.html`, { waitUntil: "load" });
  await wiper.evaluate(() => chrome.storage.session.clear());
  await wiper.close();

  // Follow-on click — pointer is gone, so this would orphan without the fallback.
  await page.bringToFront();
  await page.evaluate(() => {
    const a = document.createElement("a");
    a.href = "/wiki/Turkish_language";
    document.body.prepend(a);
    a.click();
  });
  await page.waitForLoadState("load");
  await sleep(1800);

  const viewer = await context.newPage();
  await viewer.goto(`chrome-extension://${extId}/viewer.html`, { waitUntil: "load" });
  const visits = await viewer.evaluate(async () => {
    const db = await new Promise((res, rej) => {
      const q = indexedDB.open("history-graph");
      q.onsuccess = () => res(q.result);
      q.onerror = () => rej(q.error);
    });
    return await new Promise((res, rej) => {
      const q = db.transaction("visits").objectStore("visits").getAll();
      q.onsuccess = () => res(q.result);
      q.onerror = () => rej(q.error);
    });
  });

  const byId = new Map(visits.map((v) => [v.id, v]));
  const short = (u) => u.replace("https://en.wikipedia.org/wiki/", "");
  console.log("\nafter clearing the pointer, the next click:");
  for (const v of visits.sort((a, b) => a.ts - b.ts)) {
    const parent = v.parentId ? short(byId.get(v.parentId)?.url ?? "?") : "(root)";
    console.log(`  ${short(v.url).padEnd(20)} ← ${parent}`);
  }
} finally {
  await context.close();
}