import { describe, expect, it } from "vitest";

import {
  ROUTE_FEATURE_OWNER,
  ROUTE_REGISTRY,
} from "../../src/features/installed-feature-contracts.ts";
import { ROUTE_RUNTIME } from "../../src/features/installed-feature-runtimes.tsx";
import { INSTALLED_PRODUCT_FEATURE_IDS } from "../../src/features/installed-product-manifest.ts";

/**
 * §3.5. The runtime kill switch, as it applies to *this* product.
 *
 * The template asserted the switch end to end by rendering the reference
 * feature's screens and taking them out of service. This product deleted those
 * screens during the UI migration, so that render is no longer possible: the
 * feature contributes API operations, schemas and mappers, but no route.
 *
 * Deleting the test with the screens would have removed the only thing watching
 * this seam, so what is asserted here is the invariant that survives the
 * migration and would have caught the trap the merge itself nearly introduced —
 * a route registered from a feature contract whose component no longer exists.
 * The moment a feature-owned route is registered again, the second test starts
 * asserting the switch end to end without being rewritten.
 */
describe("runtime product feature switch", () => {
  it("registers no route that cannot be mounted", () => {
    const unmountable = Object.keys(ROUTE_REGISTRY).filter(
      (routeId) => !(routeId in ROUTE_RUNTIME),
    );
    expect(unmountable).toEqual([]);
  });

  it("keeps every feature-owned route inside the installed selection", () => {
    // A route owned by a feature the manifest did not install would be
    // reachable with nothing behind it.
    const orphaned = Object.entries(ROUTE_FEATURE_OWNER)
      .filter(([routeId]) => routeId in ROUTE_REGISTRY)
      .filter(([, featureId]) => !INSTALLED_PRODUCT_FEATURE_IDS.includes(featureId));
    expect(orphaned).toEqual([]);
  });

  it("still declares a product manifest to narrow", () => {
    // The switch is only meaningful while something is selectable; if this ever
    // empties, the mechanism above is dead code rather than a guarantee.
    expect(INSTALLED_PRODUCT_FEATURE_IDS.length).toBeGreaterThan(0);
  });
});