// @vitest-environment jsdom
//
// The dialog's focus behaviour under React 18 StrictMode — its own file because StrictMode's
// mount→cleanup→mount is what the code under test reacts to, and the module-level layer stack in
// ui/Modal (and the overlay-host registry in ui/Toaster) leaks between tests in one file.
//
// Round 5 fixed this in Chrome and shipped it with NO test: the second mount found the focus
// outside the dialog (its own cleanup had just handed it back to the trigger) and moved it to the
// first focusable — taking it off an `autoFocus` field a beat after the browser had put it there.
// The command palette opened focused on its ✕ in dev and on its search field in prod, from the same
// code. Round 6 measured that deleting the fix left all 1009 tests green, which is why this exists.
//
// Same offsetParent stub as Modal.dom.test.tsx: jsdom never lays out, so every element reports
// offsetParent null and `focusablesIn` would see nothing.
import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
import { StrictMode } from "react";
import { render, screen, cleanup } from "@testing-library/react";

vi.mock("react-i18next", async (importOriginal) => {
  const actual = await importOriginal<typeof import("react-i18next")>();
  return { ...actual, useTranslation: () => ({ t: (key: string) => key }) };
});
vi.mock("../../lib/history", () => ({ useBackToClose: () => {} }));

import Modal from "./Modal";

describe("Modal focus under StrictMode", () => {
  let origDesc: PropertyDescriptor | undefined;
  beforeEach(() => {
    origDesc = Object.getOwnPropertyDescriptor(HTMLElement.prototype, "offsetParent");
    Object.defineProperty(HTMLElement.prototype, "offsetParent", {
      configurable: true,
      get(this: HTMLElement) {
        return this.isConnected ? document.body : null;
      },
    });
  });
  afterEach(() => {
    cleanup();
    if (origDesc) Object.defineProperty(HTMLElement.prototype, "offsetParent", origDesc);
  });

  it("keeps the focus its autoFocus child asked for across the double mount", () => {
    render(
      <StrictMode>
        <Modal initialFocus="close" title="t" onClose={() => {}}>
          <input aria-label="field" autoFocus />
        </Modal>
      </StrictMode>,
    );
    // Without the remembered focus the second mount lands on the first focusable — the header ✕.
    expect(document.activeElement).toBe(screen.getByLabelText("field"));
  });
});