import {
  ANONYMOUS_PRINCIPAL,
  createAuthenticatedPrincipal,
  parsePermissionId,
} from "@ekklesia/contracts";
import {
  type AuthorizationEvaluator,
  createPermissionRegistry,
} from "@ekklesia/core/authorization";
import type { EkklesiaIdentityRuntime } from "@ekklesia/core/identity";
import { Hono } from "hono";
import { describe, expect, it, vi } from "vitest";
import {
  type AuthorizationMiddlewareOptions,
  getAuthorizedPrincipal,
  requirePermission,
  requireTrustedOrigin,
} from "../src/authorization-middleware.js";

const testPermission = parsePermissionId("core.test.restricted-thing");
const unregisteredPermission = parsePermissionId("core.test.unregistered-thing");
const registry = createPermissionRegistry([
  { baseline: "restricted", description: "A restricted test permission.", id: testPermission },
]);

function fakeRuntime(overrides: Partial<EkklesiaIdentityRuntime> = {}): EkklesiaIdentityRuntime {
  return {
    handleAuthRequest: vi.fn(),
    resolvePrincipal: vi.fn().mockResolvedValue(ANONYMOUS_PRINCIPAL),
    ...overrides,
  };
}

function fakeEvaluator(overrides: Partial<AuthorizationEvaluator> = {}): AuthorizationEvaluator {
  return {
    authorize: vi.fn().mockResolvedValue({ allowed: true }),
    ...overrides,
  };
}

function buildTestApp(options: Partial<AuthorizationMiddlewareOptions> = {}) {
  const runtime = options.runtime ?? fakeRuntime();
  const evaluator = options.evaluator ?? fakeEvaluator();
  const middlewareOptions: AuthorizationMiddlewareOptions = { evaluator, registry, runtime };

  const app = new Hono();
  app.get("/protected", requirePermission(middlewareOptions, testPermission), (c) => {
    const principal = getAuthorizedPrincipal(c);
    return c.json({ principalKind: principal.kind });
  });
  app.get("/unregistered", requirePermission(middlewareOptions, unregisteredPermission), (c) =>
    c.json({ ok: true }),
  );
  app.get("/unprotected", (c) => {
    let threw = false;
    try {
      getAuthorizedPrincipal(c);
    } catch {
      threw = true;
    }
    return c.json({ threw });
  });

  return { app, evaluator, runtime };
}

describe("requirePermission", () => {
  it("allows the request through and stores the resolved principal on context when the decision is allowed", async () => {
    const runtime = fakeRuntime({
      resolvePrincipal: vi.fn().mockResolvedValue(createAuthenticatedPrincipal("user_1")),
    });
    const { app } = buildTestApp({ runtime });

    const response = await app.request("/protected");

    expect(response.status).toBe(200);
    expect(await response.json()).toEqual({ principalKind: "authenticated" });
  });

  it("returns a sanitized 403 when the evaluator denies", async () => {
    const evaluator = fakeEvaluator({ authorize: vi.fn().mockResolvedValue({ allowed: false }) });
    const { app } = buildTestApp({ evaluator });

    const response = await app.request("/protected");

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "AUTHORIZATION_DENIED" });
    expect(response.headers.get("cache-control")).toBe("no-store");
  });

  it("returns a sanitized 403 for an unregistered permission without ever resolving the principal", async () => {
    const runtime = fakeRuntime();
    const { app } = buildTestApp({ runtime });

    const response = await app.request("/unregistered");

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "AUTHORIZATION_DENIED" });
    expect(runtime.resolvePrincipal).not.toHaveBeenCalled();
  });

  it("returns a sanitized 503, not a 403, when principal resolution fails", async () => {
    const runtime = fakeRuntime({
      resolvePrincipal: vi.fn().mockRejectedValue(new Error("connection terminated")),
    });
    const { app } = buildTestApp({ runtime });

    const response = await app.request("/protected");

    expect(response.status).toBe(503);
    expect(await response.json()).toEqual({ code: "PRINCIPAL_RESOLUTION_FAILED" });
  });

  it("returns a sanitized 503, not a 403, when evaluation itself fails", async () => {
    const evaluator = fakeEvaluator({
      authorize: vi.fn().mockRejectedValue(new Error("connection terminated")),
    });
    const { app } = buildTestApp({ evaluator });

    const response = await app.request("/protected");

    expect(response.status).toBe(503);
    expect(await response.json()).toEqual({ code: "AUTHORIZATION_EVALUATION_FAILED" });
  });

  it("never leaks a raw infrastructure error message through either sanitized 503", async () => {
    const hostileMessage = "password=hunter2 host=db.internal.example port=5432";
    const evaluator = fakeEvaluator({
      authorize: vi.fn().mockRejectedValue(new Error(hostileMessage)),
    });
    const { app } = buildTestApp({ evaluator });

    const response = await app.request("/protected");
    const text = await response.text();

    expect(text).not.toContain("hunter2");
    expect(text).not.toContain("db.internal.example");
  });

  it("passes the registry's own baseline and permission id to the evaluator, never a client-supplied value", async () => {
    const evaluator = fakeEvaluator();
    const { app } = buildTestApp({ evaluator });

    // A hostile client cannot even express "use this baseline instead" — there is no request
    // field the middleware reads for it — but sending an unrelated header proves it is ignored.
    await app.request("/protected", { headers: { "x-baseline": "public" } });

    expect(evaluator.authorize).toHaveBeenCalledWith(
      expect.objectContaining({ baseline: "restricted", permission: testPermission }),
    );
  });
});

describe("requirePermission with module-owned declarations", () => {
  // requirePermission has no concept of "Core" versus "module" — it only ever consults whatever
  // registry it is given. These declarations are shaped exactly like what
  // composePlatformPermissionRegistry would contribute from a real installed module (an id
  // namespaced under a module, not `core.*`), proving the shared enforcement mechanism works
  // identically for module-owned permissions without any module-specific code path.
  const modulePublicPermission = parsePermissionId("calendar.events.list");
  const moduleAuthenticatedPermission = parsePermissionId("calendar.events.subscribe");
  const moduleRestrictedPermission = parsePermissionId("calendar.events.read");
  const moduleRegistry = createPermissionRegistry([
    {
      baseline: "public",
      description: "List public calendar events.",
      id: modulePublicPermission,
    },
    {
      baseline: "authenticated",
      description: "Subscribe to calendar event updates.",
      id: moduleAuthenticatedPermission,
    },
    {
      baseline: "restricted",
      description: "Read calendar events.",
      id: moduleRestrictedPermission,
    },
  ]);

  function buildModuleApp(
    permissionId: typeof modulePublicPermission,
    options: Partial<AuthorizationMiddlewareOptions> = {},
  ) {
    const runtime = options.runtime ?? fakeRuntime();
    const evaluator = options.evaluator ?? fakeEvaluator();
    const middlewareOptions: AuthorizationMiddlewareOptions = {
      evaluator,
      registry: moduleRegistry,
      runtime,
    };
    const app = new Hono();
    app.get("/module-protected", requirePermission(middlewareOptions, permissionId), (c) =>
      c.json({ ok: true }),
    );
    return { app, evaluator, runtime };
  }

  it("resolves a module public permission's trusted baseline and passes it to the evaluator unchanged", async () => {
    const evaluator = fakeEvaluator();
    const { app } = buildModuleApp(modulePublicPermission, { evaluator });

    const response = await app.request("/module-protected");

    expect(response.status).toBe(200);
    expect(evaluator.authorize).toHaveBeenCalledWith(
      expect.objectContaining({ baseline: "public", permission: modulePublicPermission }),
    );
  });

  it("resolves a module authenticated permission's trusted baseline and passes it to the evaluator unchanged", async () => {
    const evaluator = fakeEvaluator();
    const { app } = buildModuleApp(moduleAuthenticatedPermission, { evaluator });

    await app.request("/module-protected");

    expect(evaluator.authorize).toHaveBeenCalledWith(
      expect.objectContaining({
        baseline: "authenticated",
        permission: moduleAuthenticatedPermission,
      }),
    );
  });

  it("resolves a module restricted permission's trusted baseline and passes it to the evaluator unchanged", async () => {
    const evaluator = fakeEvaluator();
    const { app } = buildModuleApp(moduleRestrictedPermission, { evaluator });

    await app.request("/module-protected");

    expect(evaluator.authorize).toHaveBeenCalledWith(
      expect.objectContaining({
        baseline: "restricted",
        permission: moduleRestrictedPermission,
      }),
    );
  });

  it("allows an anonymous principal for a module permission the evaluator authorizes", async () => {
    const runtime = fakeRuntime({
      resolvePrincipal: vi.fn().mockResolvedValue(ANONYMOUS_PRINCIPAL),
    });
    const { app } = buildModuleApp(modulePublicPermission, { runtime });

    const response = await app.request("/module-protected");

    expect(response.status).toBe(200);
  });

  it("allows an authenticated principal for a module permission the evaluator authorizes", async () => {
    const runtime = fakeRuntime({
      resolvePrincipal: vi.fn().mockResolvedValue(createAuthenticatedPrincipal("user_1")),
    });
    const { app } = buildModuleApp(moduleRestrictedPermission, { runtime });

    const response = await app.request("/module-protected");

    expect(response.status).toBe(200);
  });

  it("denies a module permission the evaluator does not authorize", async () => {
    const evaluator = fakeEvaluator({ authorize: vi.fn().mockResolvedValue({ allowed: false }) });
    const { app } = buildModuleApp(moduleRestrictedPermission, { evaluator });

    const response = await app.request("/module-protected");

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "AUTHORIZATION_DENIED" });
  });

  it("denies a module permission absent from the registry before ever resolving the principal or consulting the evaluator", async () => {
    const runtime = fakeRuntime();
    const evaluator = fakeEvaluator();
    const absentModulePermission = parsePermissionId("scheduler.jobs.read");
    const { app } = buildModuleApp(absentModulePermission, { evaluator, runtime });

    const response = await app.request("/module-protected");

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "AUTHORIZATION_DENIED" });
    expect(runtime.resolvePrincipal).not.toHaveBeenCalled();
    expect(evaluator.authorize).not.toHaveBeenCalled();
  });

  it("never lets a client-supplied baseline influence the decision for a module permission", async () => {
    const evaluator = fakeEvaluator();
    const { app } = buildModuleApp(moduleRestrictedPermission, { evaluator });

    // A hostile client cannot make a restricted module permission behave as public — there is no
    // request field the middleware reads for a baseline override.
    await app.request("/module-protected", {
      headers: { "x-baseline": "public", "x-permission-baseline": "public" },
    });

    expect(evaluator.authorize).toHaveBeenCalledWith(
      expect.objectContaining({ baseline: "restricted" }),
    );
  });
});

describe("getAuthorizedPrincipal", () => {
  it("throws when called on a route requirePermission never protected", async () => {
    const { app } = buildTestApp();

    const response = await app.request("/unprotected");

    expect(await response.json()).toEqual({ threw: true });
  });
});

describe("requireTrustedOrigin", () => {
  const trustedOrigins = new Set(["https://dashboard.example.test"]);

  function buildOriginApp() {
    const app = new Hono();
    app.post("/mutate", requireTrustedOrigin(trustedOrigins), (c) => c.json({ ok: true }));
    return app;
  }

  it("allows a request from a trusted origin", async () => {
    const app = buildOriginApp();

    const response = await app.request("/mutate", {
      headers: { origin: "https://dashboard.example.test" },
      method: "POST",
    });

    expect(response.status).toBe(200);
  });

  it("rejects a request with no Origin header at all", async () => {
    const app = buildOriginApp();

    const response = await app.request("/mutate", { method: "POST" });

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "UNTRUSTED_ORIGIN" });
  });

  it("rejects a request from an untrusted origin", async () => {
    const app = buildOriginApp();

    const response = await app.request("/mutate", {
      headers: { origin: "https://evil.example.test" },
      method: "POST",
    });

    expect(response.status).toBe(403);
    expect(await response.json()).toEqual({ code: "UNTRUSTED_ORIGIN" });
  });
});