import { describe, expect, it } from "vitest";
import {
  type ModuleUiHostContext,
  type ModuleUiNavigation,
  ModuleUiNavigationError,
  NO_MODULE_UI_CONTRIBUTIONS,
} from "../src/index.js";

/** The navigation capability's public surface (ADR 0063). Its behaviour is the host's: the
 * Dashboard's implementation is proven in `surfaces/shell/tests/module-navigation.test.tsx`. */
describe("module UI navigation contract", () => {
  it("reports a refused path with a stable code and a fixed message that never echoes the path", () => {
    for (const code of [
      "MODULE_NAVIGATION_PATH_INVALID",
      "MODULE_NAVIGATION_PATH_UNKNOWN",
    ] as const) {
      const error = new ModuleUiNavigationError(code);
      expect(error).toBeInstanceOf(Error);
      expect(error.name).toBe("ModuleUiNavigationError");
      expect(error.code).toBe(code);
      expect(error.stack).toBe(`ModuleUiNavigationError: ${error.message}`);
      expect(error.message).not.toMatch(/[/:?#]/u);
    }
  });

  it("keeps a context built before navigation existed a complete, valid context", () => {
    // Exactly the seven members every host supplied before ADR 0063, with no `navigation` member at
    // all. This must keep compiling unchanged: `tsc` over this file is the compatibility proof, and
    // `satisfies` makes the check exact rather than structural-by-accident.
    const preNavigationContext = {
      api: { request: async () => new Response(null, { status: 204 }) },
      contributions: NO_MODULE_UI_CONTRIBUTIONS,
      display: undefined,
      moduleId: "announcements",
      permissions: { has: () => false },
      principal: { kind: "anonymous" },
      realtime: { subscribe: () => ({ close: () => undefined }) },
    } satisfies ModuleUiHostContext;
    const asContext: ModuleUiHostContext = preNavigationContext;

    expect("navigation" in asContext).toBe(false);
    expect(asContext.navigation?.location().path).toBeUndefined();
  });

  it("lets a host supply navigation, omit it, or set it to undefined, and a module feature-detect it", () => {
    const navigation: ModuleUiNavigation = {
      link: () => ({ href: "/m/x", onClick: () => undefined }),
      location: () => ({ page: "x", path: "x" }),
      navigate: () => undefined,
      settings: undefined,
      subscribe: () => () => undefined,
    };
    const where = (context: Pick<ModuleUiHostContext, "navigation">): string =>
      context.navigation?.location().path ?? "no navigation";

    expect(where({ navigation })).toBe("x");
    expect(where({})).toBe("no navigation");
    expect(where({ navigation: undefined })).toBe("no navigation");
    // Present, it must be the real capability — not any object.
    // @ts-expect-error a navigation member must satisfy ModuleUiNavigation
    expect(where({ navigation: { location: () => "x" } })).toBeDefined();
  });
});