import { describe, expect, it, vi } from "vitest";
import {
  bootstrapHost,
  type HostModuleUiDescriptor,
  loadDashboardNavigation,
  loadHostPrincipal,
  parseDashboardNavigation,
  parseHostPrincipal,
} from "../src/host-protocol.js";
import { createModuleUiContext, moduleUiSourceUrl } from "../src/module-context.js";

const apiBaseUrl = "https://ekklesia.example.test";

function jsonResponse(body: unknown, status = 200): Response {
  return new Response(JSON.stringify(body), {
    headers: { "content-type": "application/json" },
    status,
  });
}

/** A fetch double that answers the two platform paths and records every call, so the tests can
 * assert both the URL the shell built and the credentials it used. */
function stubFetch(routes: Readonly<Record<string, () => Response>>) {
  const calls: Array<{ init: RequestInit | undefined; url: string }> = [];
  const implementation = vi.fn(async (input: RequestInfo | URL, init?: RequestInit) => {
    const url = String(input);
    calls.push({ init, url });
    const route = Object.entries(routes).find(([path]) => url === `${apiBaseUrl}${path}`);
    if (!route) {
      return new Response(JSON.stringify({ code: "NOT_FOUND" }), { status: 404 });
    }
    return route[1]();
  });
  return { calls, implementation: implementation as unknown as typeof fetch };
}

const inventoryPayload = {
  modules: [
    {
      api: { baseUrl: "/api/v1/modules/example" },
      id: "example",
      permissions: ["example.records.read"],
      realtime: { baseUrl: "/api/v1/module-realtime/example" },
      ui: { url: "/api/v1/module-ui/example/0.1.0" },
      version: "0.1.0",
    },
  ],
};

const calendarDescriptor: HostModuleUiDescriptor = {
  apiBaseUrl: "/api/v1/modules/calendar",
  id: "calendar",
  permissions: [],
  realtimeBaseUrl: "/api/v1/module-realtime/calendar",
  uiUrl: "/api/v1/module-ui/calendar/2.0.0",
  version: "2.0.0",
};

const navigationPayload = {
  groups: [
    {
      id: "media",
      label: "Media",
      modules: [{ module: inventoryPayload.modules[0], name: "Example Module" }],
      order: 10,
    },
  ],
  ungrouped: [
    {
      module: {
        api: { baseUrl: "/api/v1/modules/calendar" },
        id: "calendar",
        permissions: [],
        realtime: { baseUrl: "/api/v1/module-realtime/calendar" },
        ui: { url: "/api/v1/module-ui/calendar/2.0.0" },
        version: "2.0.0",
      },
      name: "Calendar",
    },
  ],
};

const exampleDescriptor: HostModuleUiDescriptor = {
  apiBaseUrl: "/api/v1/modules/example",
  id: "example",
  permissions: ["example.records.read"],
  realtimeBaseUrl: "/api/v1/module-realtime/example",
  uiUrl: "/api/v1/module-ui/example/0.1.0",
  version: "0.1.0",
};

function navigationWithModule(module: unknown): unknown {
  return { groups: [], ungrouped: [{ module, name: "Example Module" }] };
}

describe("host protocol — descriptor validation", () => {
  it("parses a well-formed descriptor out of the navigation view", () => {
    const navigation = parseDashboardNavigation(navigationWithModule(inventoryPayload.modules[0]));

    expect(navigation.ungrouped[0]?.descriptor).toEqual(exampleDescriptor);
  });

  it("rejects a malformed descriptor rather than yielding a half-built one", () => {
    const base = inventoryPayload.modules[0] as Record<string, unknown>;
    const malformed: unknown[] = [
      {},
      { id: "example", version: "0.1.0" },
      { ...base, ui: {} },
      { ...base, api: { baseUrl: "" } },
      { ...base, realtime: {} },
      { ...base, permissions: "example.records.read" },
      { ...base, permissions: [42] },
      // Every URL must be root-relative, so a value that would resolve against another origin is
      // refused rather than silently used to fetch browser code.
      { ...base, ui: { url: "https://evil.example.test/x.js" } },
      { ...base, ui: { url: "//evil.example.test/x.js" } },
      { ...base, ui: { url: "relative/x.js" } },
      { ...base, api: { baseUrl: "https://evil.example.test/api" } },
      { ...base, realtime: { baseUrl: "https://evil.example.test/live" } },
      { ...base, realtime: { baseUrl: "//evil.example.test/live" } },
      { ...base, realtime: { baseUrl: "/\\evil.example.test/live" } },
    ];
    for (const module of malformed) {
      expect(
        () => parseDashboardNavigation(navigationWithModule(module)),
        JSON.stringify(module),
      ).toThrowError(expect.objectContaining({ code: "HOST_RESPONSE_INVALID" }));
    }
  });

  it("distinguishes an authentication challenge from an authorization denial", async () => {
    const unauthenticated = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse({ code: "AUTHORIZATION_DENIED" }, 401),
    });
    await expect(
      loadDashboardNavigation({ apiBaseUrl, fetch: unauthenticated.implementation }),
    ).rejects.toMatchObject({ code: "HOST_UNAUTHENTICATED" });

    const forbidden = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse({ code: "AUTHORIZATION_DENIED" }, 403),
    });
    await expect(
      loadDashboardNavigation({ apiBaseUrl, fetch: forbidden.implementation }),
    ).rejects.toMatchObject({ code: "HOST_ACCESS_DENIED" });

    const { implementation } = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse({ code: "INTERNAL_ERROR" }, 500),
    });
    await expect(
      loadDashboardNavigation({ apiBaseUrl, fetch: implementation }),
    ).rejects.toMatchObject({ code: "HOST_REQUEST_FAILED" });
  });

  it("never renders a caught cause, a URL, or a server path in its message", async () => {
    const failing = vi.fn(async () => {
      throw new Error("connect ECONNREFUSED /run/postgres/.s.PGSQL.5432");
    }) as unknown as typeof fetch;

    const error = await loadDashboardNavigation({ apiBaseUrl, fetch: failing }).catch(
      (caught: unknown) => caught,
    );

    expect(error).toMatchObject({ code: "HOST_REQUEST_FAILED" });
    expect((error as Error).message).toBe("Ekklesia could not be reached.");
    expect((error as Error).message).not.toContain("PGSQL");
  });
});

describe("host protocol — principal", () => {
  it("maps the platform principal onto the browser-safe SDK shape", () => {
    expect(parseHostPrincipal({ kind: "anonymous" })).toEqual({ kind: "anonymous" });
    expect(parseHostPrincipal({ kind: "authenticated", userId: "user-1" })).toEqual({
      kind: "authenticated",
      userId: "user-1",
    });
  });

  it("carries nothing beyond kind and userId, even when the server sends more", () => {
    const principal = parseHostPrincipal({
      email: "someone@example.test",
      kind: "authenticated",
      roles: ["owner"],
      sessionToken: "secret",
      userId: "user-1",
    });

    expect(Object.keys(principal).sort()).toEqual(["kind", "userId"]);
    expect(JSON.stringify(principal)).not.toContain("secret");
  });

  it("rejects a principal it does not recognize", () => {
    for (const payload of [null, {}, { kind: "authenticated" }, { kind: "owner" }]) {
      expect(() => parseHostPrincipal(payload)).toThrowError(
        expect.objectContaining({ code: "HOST_RESPONSE_INVALID" }),
      );
    }
  });
});

describe("host protocol — Dashboard navigation", () => {
  it("parses the server's resolved arrangement, keeping the mount descriptor nested", () => {
    const navigation = parseDashboardNavigation(navigationPayload);

    expect(navigation.groups.map((group) => [group.id, group.label])).toEqual([["media", "Media"]]);
    expect(navigation.groups[0]?.modules).toEqual([
      { descriptor: exampleDescriptor, name: "Example Module" },
    ]);
    expect(navigation.ungrouped).toEqual([{ descriptor: calendarDescriptor, name: "Calendar" }]);
  });

  it("rejects a malformed navigation document rather than rendering half of it", () => {
    const malformed: unknown[] = [
      {},
      { groups: [] },
      { groups: {}, ungrouped: [] },
      { groups: [{ id: "media", label: "Media" }], ungrouped: [] },
      { groups: [{ id: "media", modules: [] }], ungrouped: [] },
      { groups: [], ungrouped: [{ name: "Example" }] },
      { groups: [], ungrouped: [{ module: inventoryPayload.modules[0] }] },
      // An absolute artifact URL must be refused here exactly as in the inventory.
      {
        groups: [],
        ungrouped: [
          {
            module: {
              ...inventoryPayload.modules[0],
              ui: { url: "https://evil.example.test/x.js" },
            },
            name: "Example",
          },
        ],
      },
    ];
    for (const payload of malformed) {
      expect(() => parseDashboardNavigation(payload), JSON.stringify(payload)).toThrowError(
        expect.objectContaining({ code: "HOST_RESPONSE_INVALID" }),
      );
    }
  });

  it("fetches navigation from the platform path with credentials", async () => {
    const { calls, implementation } = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse(navigationPayload),
    });

    await loadDashboardNavigation({ apiBaseUrl, fetch: implementation });

    expect(calls[0]?.url).toBe(`${apiBaseUrl}/api/v1/dashboard/navigation`);
    expect(calls[0]?.init?.credentials).toBe("include");
  });
});

describe("host protocol — bootstrap", () => {
  it("resolves the principal and then the Dashboard navigation", async () => {
    const { calls, implementation } = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse(navigationPayload),
      "/api/v1/principal": () => jsonResponse({ kind: "authenticated", userId: "user-1" }),
    });

    const bootstrap = await bootstrapHost({ apiBaseUrl, fetch: implementation });

    expect(calls.map((call) => call.url)).toEqual([
      `${apiBaseUrl}/api/v1/principal`,
      `${apiBaseUrl}/api/v1/dashboard/navigation`,
    ]);
    expect(bootstrap.principal).toEqual({ kind: "authenticated", userId: "user-1" });
    expect(bootstrap.navigation.groups[0]?.modules[0]?.descriptor).toEqual(exampleDescriptor);
  });

  it("never requests navigation for an anonymous viewer", async () => {
    const { calls, implementation } = stubFetch({
      "/api/v1/dashboard/navigation": () => jsonResponse(navigationPayload),
      "/api/v1/principal": () => jsonResponse({ kind: "anonymous" }),
    });

    const bootstrap = await bootstrapHost({ apiBaseUrl, fetch: implementation });

    expect(bootstrap.principal).toEqual({ kind: "anonymous" });
    expect(bootstrap.navigation).toEqual({ groups: [], ungrouped: [] });
    expect(calls.map((call) => call.url)).toEqual([`${apiBaseUrl}/api/v1/principal`]);
  });

  it("sends the platform principal request with credentials too", async () => {
    const { calls, implementation } = stubFetch({
      "/api/v1/principal": () => jsonResponse({ kind: "anonymous" }),
    });

    await loadHostPrincipal({ apiBaseUrl, fetch: implementation });

    expect(calls[0]?.init?.credentials).toBe("include");
  });
});

describe("module UI host context", () => {
  function contextFor(fetchImplementation: typeof fetch, descriptor = exampleDescriptor) {
    return createModuleUiContext({
      config: { apiBaseUrl, fetch: fetchImplementation },
      descriptor,
      principal: { kind: "authenticated", userId: "user-1" },
    });
  }

  function recordingFetch() {
    const calls: Array<{ init: RequestInit | undefined; url: string }> = [];
    const implementation = vi.fn(async (input: RequestInfo | URL, init?: RequestInit) => {
      calls.push({ init, url: String(input) });
      return new Response("[]", { status: 200 });
    });
    return { calls, implementation: implementation as unknown as typeof fetch };
  }

  it("resolves a module-relative path onto the server-produced module API root", async () => {
    const { calls, implementation } = recordingFetch();

    await contextFor(implementation).api.request("records");

    expect(calls[0]?.url).toBe(`${apiBaseUrl}/api/v1/modules/example/records`);
  });

  it("normalizes a leading slash and preserves query strings and nested paths", async () => {
    const { calls, implementation } = recordingFetch();
    const api = contextFor(implementation).api;

    await api.request("/records");
    await api.request("records?since=2026-01-01&limit=10");
    await api.request("records/abc/comments");
    await api.request("");

    expect(calls.map((call) => call.url)).toEqual([
      `${apiBaseUrl}/api/v1/modules/example/records`,
      `${apiBaseUrl}/api/v1/modules/example/records?since=2026-01-01&limit=10`,
      `${apiBaseUrl}/api/v1/modules/example/records/abc/comments`,
      `${apiBaseUrl}/api/v1/modules/example`,
    ]);
  });

  it("forwards the module's own RequestInit and imposes credentials", async () => {
    const { calls, implementation } = recordingFetch();

    await contextFor(implementation).api.request("records", {
      body: JSON.stringify({ value: "one" }),
      headers: { "content-type": "application/json" },
      method: "POST",
    });

    expect(calls[0]?.init).toMatchObject({
      credentials: "include",
      headers: { "content-type": "application/json" },
      method: "POST",
    });
  });

  it("reports only 401/403 to the host while returning the module's original response", async () => {
    const statuses = [401, 403, 404, 200];
    const onAuthorizationResponse = vi.fn();
    const implementation = vi.fn(async () => {
      const status = statuses.shift();
      if (status === undefined) {
        throw new Error("unexpected request");
      }
      return new Response("module response", { status });
    }) as unknown as typeof fetch;
    const context = createModuleUiContext({
      config: { apiBaseUrl, fetch: implementation },
      descriptor: exampleDescriptor,
      onAuthorizationResponse,
      principal: { kind: "authenticated", userId: "user-1" },
    });

    const responses = await Promise.all([
      context.api.request("one"),
      context.api.request("two"),
      context.api.request("three"),
      context.api.request("four"),
    ]);

    expect(responses.map((response) => response.status)).toEqual([401, 403, 404, 200]);
    expect(onAuthorizationResponse.mock.calls).toEqual([[401], [403]]);
  });

  it("refuses to address anything outside the module's own API", async () => {
    const { calls, implementation } = recordingFetch();
    const api = contextFor(implementation).api;

    const escapes = [
      "../calendar/records",
      "records/../../calendar/records",
      "/../../v1/grants",
      "https://evil.example.test/steal",
      "//evil.example.test/steal",
      "HTTPS://evil.example.test/steal",
      "javascript:alert(1)",
    ];
    for (const path of escapes) {
      await expect(api.request(path), path).rejects.toMatchObject({
        code: "MODULE_API_PATH_INVALID",
      });
    }
    // Not one of them reached the network.
    expect(calls).toEqual([]);
  });

  it("gives each module only its own API root", async () => {
    const { calls, implementation } = recordingFetch();
    const calendar: HostModuleUiDescriptor = {
      apiBaseUrl: "/api/v1/modules/calendar",
      id: "calendar",
      permissions: [],
      realtimeBaseUrl: "/api/v1/module-realtime/calendar",
      uiUrl: "/api/v1/module-ui/calendar/2.0.0",
      version: "2.0.0",
    };

    await contextFor(implementation).api.request("records");
    await contextFor(implementation, calendar).api.request("events");

    expect(calls.map((call) => call.url)).toEqual([
      `${apiBaseUrl}/api/v1/modules/example/records`,
      `${apiBaseUrl}/api/v1/modules/calendar/events`,
    ]);
  });

  it("builds permission hints from the server's granted set, never a default of true", () => {
    const { implementation } = recordingFetch();

    const granted = contextFor(implementation).permissions;
    const none = contextFor(implementation, { ...exampleDescriptor, permissions: [] }).permissions;

    expect(granted.has("example.records.read")).toBe(true);
    expect(granted.has("example.records.write")).toBe(false);
    // A module the viewer holds nothing for gets a hint set that answers false to everything.
    expect(none.has("example.records.read")).toBe(false);
    expect(none.has("core.authorization.grants.manage")).toBe(false);
  });

  it("exposes exactly the five contract members and the browser principal", () => {
    const { implementation } = recordingFetch();

    const context = contextFor(implementation);

    expect(Object.keys(context).sort()).toEqual([
      "api",
      "moduleId",
      "permissions",
      "principal",
      "realtime",
    ]);
    expect(context.moduleId).toBe("example");
    expect(context.principal).toEqual({ kind: "authenticated", userId: "user-1" });
  });

  it("resolves the artifact URL from the descriptor the server produced", () => {
    expect(moduleUiSourceUrl({ apiBaseUrl }, exampleDescriptor)).toBe(
      `${apiBaseUrl}/api/v1/module-ui/example/0.1.0`,
    );
    // Same descriptor, a different deployment origin: the shell composes, it never authors.
    expect(moduleUiSourceUrl({ apiBaseUrl: "http://127.0.0.1:3000" }, exampleDescriptor)).toBe(
      "http://127.0.0.1:3000/api/v1/module-ui/example/0.1.0",
    );
  });
});