import { describe, it, expect, beforeEach } from "vitest";
import {
  reportServerVersion,
  subscribeNewVersion,
  getNewVersion,
  BUILD_VERSION,
  __resetVersionStateForTest,
} from "../admin/utils/appVersion";

/**
 * Client store backing the "new version available" banner. The server stamps
 * X-App-Version on every response; apiFetch feeds it here. A version that
 * differs from the one baked into THIS bundle (BUILD_VERSION) means a deploy
 * happened → latch it and notify subscribers (the banner).
 */

describe("appVersion store", () => {
  beforeEach(() => __resetVersionStateForTest());

  it("ignores the same version, empty, or null", () => {
    reportServerVersion(BUILD_VERSION);
    reportServerVersion("");
    reportServerVersion(null);
    reportServerVersion(undefined);
    expect(getNewVersion()).toBeNull();
  });

  it("latches + notifies once when the server reports a different version", () => {
    let notified = 0;
    const unsub = subscribeNewVersion(() => {
      notified++;
    });

    reportServerVersion(`${BUILD_VERSION}-next`);
    expect(getNewVersion()).toBe(`${BUILD_VERSION}-next`);
    expect(notified).toBe(1);

    // Idempotent: once a new version is known, further reports don't re-notify
    // or overwrite (the banner is already showing).
    reportServerVersion("99.0.0");
    expect(getNewVersion()).toBe(`${BUILD_VERSION}-next`);
    expect(notified).toBe(1);

    unsub();
  });
});