siftlode/frontend/src/lib/localData.dom.test.ts

// @vitest-environment jsdom
//
// A browser holds ONE account's local state: the keys carry no account id, and the browser records
// whose they are. These pin the boot-time claim — the move of the old per-account keys onto the plain
// ones, the wipe when another account starts here — and the guard that keeps a tab from reading or
// writing them before its account is known, or after another tab has claimed them for someone else.
import { beforeEach, describe, expect, it, vi } from "vitest";

beforeEach(() => {
  localStorage.clear();
  sessionStorage.clear();
  vi.resetModules(); // the claim lives in module state: each case starts unclaimed
});

const storage = () => import("./storage");
const keys = (s: Storage) => Object.keys(s).sort();

describe("claiming the browser's local data", () => {
  it("moves the account's old per-account copies onto the plain keys and drops other accounts' copies", async () => {
    localStorage.setItem("siftlode.filters.1", '{"q":"mine"}');
    localStorage.setItem("siftlode.filters.7", '{"q":"theirs"}');
    localStorage.setItem("siftlode.onboarding.dismissed.1", "1");
    localStorage.setItem("siftlode.notifications.7", "[]");
    sessionStorage.setItem("siftlode.settingsTab.1", "account");
    sessionStorage.setItem("siftlode.settingsTab.7", "plex");
    const { claimLocalData, LS } = await storage();

    claimLocalData(1);

    expect(localStorage.getItem(LS.filters)).toBe('{"q":"mine"}');
    expect(localStorage.getItem(LS.onboardingDismissed)).toBe("1");
    expect(sessionStorage.getItem(LS.settingsTab)).toBe("account");
    expect(keys(localStorage)).toEqual(
      ["siftlode.filters", "siftlode.onboarding.dismissed", "siftlode.owner"].sort(),
    );
    expect(keys(sessionStorage)).toEqual(["siftlode.owner", "siftlode.settingsTab"]);
  });

  it("an old per-account copy wins over a plain key already there", async () => {
    localStorage.setItem("siftlode.hints", "1");
    localStorage.setItem("siftlode.hints.1", "0");
    const { claimLocalData } = await storage();

    claimLocalData(1);

    expect(localStorage.getItem("siftlode.hints")).toBe("0");
  });

  it("leaves a key that only looks like an account copy alone", async () => {
    localStorage.setItem("siftlode.somethingElse.3", "x");
    const { claimLocalData } = await storage();

    claimLocalData(1);

    expect(localStorage.getItem("siftlode.somethingElse.3")).toBe("x");
  });

  it("drops the per-tab account pin the multi-account build kept", async () => {
    sessionStorage.setItem("siftlode.activeAccount", "1");
    sessionStorage.setItem("siftlode.nextAccount", "7");
    const { claimLocalData } = await storage();

    claimLocalData(1);

    expect(sessionStorage.getItem("siftlode.activeAccount")).toBeNull();
    expect(sessionStorage.getItem("siftlode.nextAccount")).toBeNull();
  });

  it("another account starting here wipes the previous one's state, but not the browser's own", async () => {
    localStorage.setItem("siftlode.owner", "7");
    localStorage.setItem("siftlode.filters", '{"q":"theirs"}');
    localStorage.setItem("siftlode.theme", "dark");
    localStorage.setItem("siftlode.watchResume", '{"tok":{"at":5,"t":1}}');
    localStorage.setItem("siftlode.watchRepeat", "false");
    localStorage.setItem("unrelated.key", "kept");
    sessionStorage.setItem("siftlode.settingsTab", "plex");
    const { claimLocalData } = await storage();

    claimLocalData(1);

    expect(keys(localStorage)).toEqual(
      ["siftlode.owner", "siftlode.watchRepeat", "siftlode.watchResume", "unrelated.key"].sort(),
    );
    expect(localStorage.getItem("siftlode.owner")).toBe("1");
    expect(keys(sessionStorage)).toEqual(["siftlode.owner"]);
  });

  it("a tab reloading for the account another tab claimed the browser for drops its own view state", async () => {
    // Tab 2 signed in as 7 and claimed the browser; this tab still holds 1's sub-tab and the
    // onboarding flow 1 was in. Its sessionStorage is its own, so the browser's owner says nothing
    // about it.
    localStorage.setItem("siftlode.owner", "7");
    sessionStorage.setItem("siftlode.owner", "1");
    sessionStorage.setItem("siftlode.settingsTab", "plex");
    sessionStorage.setItem("siftlode.onboarding.active", "1");
    const { claimLocalData } = await storage();

    claimLocalData(7);

    expect(keys(sessionStorage)).toEqual(["siftlode.owner"]);
    expect(sessionStorage.getItem("siftlode.owner")).toBe("7");
  });

  it("the same account starting again keeps everything", async () => {
    localStorage.setItem("siftlode.owner", "1");
    localStorage.setItem("siftlode.filters", '{"q":"mine"}');
    sessionStorage.setItem("siftlode.settingsTab", "account");
    const { claimLocalData } = await storage();

    claimLocalData(1);

    expect(localStorage.getItem("siftlode.filters")).toBe('{"q":"mine"}');
    expect(sessionStorage.getItem("siftlode.settingsTab")).toBe("account");
  });

  it("tells the stores read at import to read again", async () => {
    const { claimLocalData, onLocalDataClaimed } = await storage();
    const reread = vi.fn();
    onLocalDataClaimed(reread);

    claimLocalData(1);

    expect(reread).toHaveBeenCalledOnce();
  });
});

describe("the account's local state", () => {
  it("is neither read nor written before the account is known", async () => {
    localStorage.setItem("siftlode.hints", "0");
    const { getAccountRaw, setAccountRaw, readAccount, writeAccount, ownKey } = await storage();

    expect(getAccountRaw("siftlode.hints")).toBeNull();
    expect(readAccount("siftlode.filters", "fallback")).toBe("fallback");
    expect(ownKey("siftlode.filters")).toBeNull();
    setAccountRaw("siftlode.page", "plex");
    writeAccount("siftlode.filters", { q: "x" });

    expect(localStorage.getItem("siftlode.page")).toBeNull();
    expect(localStorage.getItem("siftlode.filters")).toBeNull();
  });

  it("is read and written under the plain key once claimed", async () => {
    const { claimLocalData, getAccountRaw, setAccountRaw, ownKey } = await storage();
    claimLocalData(1);

    setAccountRaw("siftlode.page", "plex");

    expect(localStorage.getItem("siftlode.page")).toBe("plex");
    expect(getAccountRaw("siftlode.page")).toBe("plex");
    expect(ownKey("siftlode.filters")).toBe("siftlode.filters");
  });

  it("stops being touched once another tab has claimed the browser for someone else", async () => {
    const { claimLocalData, getAccountRaw, setAccountRaw } = await storage();
    claimLocalData(1);
    setAccountRaw("siftlode.page", "plex");

    // Another tab signed in as account 6: its boot wiped the state and recorded the new owner.
    localStorage.clear();
    localStorage.setItem("siftlode.owner", "6");
    localStorage.setItem("siftlode.hints", "0"); // account 6's
    setAccountRaw("siftlode.page", "feed");

    expect(localStorage.getItem("siftlode.page")).toBeNull();
    expect(getAccountRaw("siftlode.hints")).toBeNull();
  });
});