/**
 * Sicherheits-Grundtests der Baseline (Express 5, node:test).
 *
 * Diese Datei NICHT pro App anpassen. Alles App-Spezifische steht in security.config.ts.
 * Regel: Wird ein Test hier rot, wird der App-Code repariert, nie der Test gelockert.
 *
 * Läuft mit `node --import tsx --test tests/security/baseline.test.ts`.
 */
import assert from "node:assert/strict";
import type { AddressInfo } from "node:net";
import { after, before, describe, it } from "node:test";
import { collectRoutes, fillPath, installRouteRecorder, type Route } from "./route-inventory.ts";

installRouteRecorder();
// Erst NACH installRouteRecorder() importieren, sonst fehlen die Mount-Pfade.
const { default: config } = await import("./security.config.ts");

type Headers = Record<string, string>;
const BODY_METHODS = new Set(["POST", "PUT", "PATCH"]);

let app: Awaited<ReturnType<typeof config.createApp>>;
let server: import("node:http").Server;
let baseUrl = "";
let owner: Headers = {};
let other: Headers = {};

const key = (r: Route) => `${r.method} ${r.path}`;
const protectedRoutes = () => collectRoutes(app).filter((r) => !config.publicRoutes.includes(key(r)));
const fill = (template: string, obj: Record<string, unknown>) =>
  template.replace(/\{(\w+)\}/g, (_, name: string) => String(obj[name]));

async function call(method: string, path: string, headers: Headers = {}, body?: unknown) {
  const init: RequestInit = { method, headers: { ...headers }, redirect: "manual" };
  if (typeof body === "string") {
    init.body = body;
    (init.headers as Headers)["content-type"] = "application/json";
  } else if (body !== undefined || BODY_METHODS.has(method)) {
    init.body = JSON.stringify(body ?? {});
    (init.headers as Headers)["content-type"] = "application/json";
  }
  return fetch(baseUrl + path, init);
}

before(async () => {
  app = await config.createApp();
  server = app.listen(0, "127.0.0.1");
  await new Promise((resolve) => server.once("listening", resolve));
  baseUrl = `http://127.0.0.1:${(server.address() as AddressInfo).port}`;
  owner = await config.ownerHeaders(baseUrl);
  other = await config.otherHeaders(baseUrl);
});

after(() => new Promise<void>((resolve) => server.close(() => resolve())));

describe("Authentifizierung", () => {
  it("Leerlauf-Sperre: genug geschützte Routen erkannt", () => {
    const found = protectedRoutes();
    assert.ok(
      found.length >= config.minProtectedRoutes,
      `Nur ${found.length} geschützte Routen erkannt, erwartet >= ${config.minProtectedRoutes}: ${found.map(key).join(", ")}`,
    );
    assert.ok(!found.some((r) => r.path.includes("?")), "Mount-Pfad nicht auflösbar (Array/RegExp in app.use)");
  });

  it("Public-Liste enthält keine Leichen", () => {
    const existing = new Set(collectRoutes(app).map(key));
    const stale = config.publicRoutes.filter((r) => !existing.has(r));
    assert.deepEqual(stale, [], `Public-Routen existieren nicht mehr: ${stale.join(", ")}`);
  });

  it("jede Route verlangt Login", async () => {
    const failures: string[] = [];
    for (const route of protectedRoutes()) {
      const res = await call(route.method, fillPath(route.path));
      if (![401, 403].includes(res.status)) failures.push(`${key(route)} -> ${res.status}`);
    }
    assert.deepEqual(failures, [], `Ohne Login erreichbar:\n${failures.join("\n")}`);
  });

  it("gefälschte Identität wird abgelehnt", async () => {
    const failures: string[] = [];
    for (const route of protectedRoutes()) {
      const res = await call(route.method, fillPath(route.path), config.spoofedHeaders);
      if (![401, 403].includes(res.status)) failures.push(`${key(route)} -> ${res.status}`);
    }
    assert.deepEqual(failures, [], `Gefälschte Identität akzeptiert:\n${failures.join("\n")}`);
  });
});

// idorGap: bewusst offene, dokumentierte Lücke. Die Tests laufen trotzdem und zeigen den
// Ist-Zustand, werden aber als TODO gemeldet statt den Lauf rot zu machen.
const idorGap = (config as { idorGap?: string }).idorGap;
const idorOptions = idorGap ? { todo: `OFFENE LÜCKE: ${idorGap}` } : {};

describe("Autorisierung (IDOR)", () => {
  it("fremde Objekte sind nicht erreichbar, eigene schon", idorOptions, async () => {
    assert.ok(config.idorCases.length > 0, "idorCases konfigurieren");
    const failures: string[] = [];
    for (const c of config.idorCases) {
      const obj = await config.createOwnedObject(baseUrl, owner);
      const path = fill(c.path, obj);
      const foreign = await call(c.method, path, other, c.body);
      if (![403, 404].includes(foreign.status)) failures.push(`${c.method} ${path} als Fremder -> ${foreign.status}`);
      // Gegenprobe: sonst wäre ein Endpunkt, der immer 404 liefert, "sicher".
      const own = await call(c.method, path, owner, c.body);
      if (own.status < 200 || own.status >= 300) failures.push(`${c.method} ${path} als Besitzer -> ${own.status} (Gegenprobe)`);
    }
    assert.deepEqual(failures, [], failures.join("\n"));
  });

  it("Listen enthalten keine fremden Objekte", idorOptions, async () => {
    assert.ok(config.listCases.length > 0, "listCases konfigurieren");
    const obj = await config.createOwnedObject(baseUrl, owner);
    for (const { path, key: field } of config.listCases) {
      const ids = async (h: Headers) => ((await (await call("GET", path, h)).json()) as Record<string, unknown>[]).map((i) => i[field]);
      assert.ok((await ids(owner)).includes(obj[field]), `${path}: Besitzer sieht eigenes Objekt nicht (Gegenprobe)`);
      assert.ok(!(await ids(other)).includes(obj[field]), `${path}: fremdes Objekt in der Liste`);
    }
  });
});

describe("Eingaben", () => {
  it("unbekannte/geschützte Felder werden abgelehnt (Mass Assignment)", async () => {
    assert.ok(config.massAssignmentCases.length > 0, "massAssignmentCases konfigurieren");
    const obj = await config.createOwnedObject(baseUrl, owner);
    const failures: string[] = [];
    for (const c of config.massAssignmentCases) {
      const res = await call(c.method, fill(c.path, obj), owner, c.body);
      if (![400, 422].includes(res.status)) failures.push(`${c.method} ${c.path} ${JSON.stringify(c.body)} -> ${res.status}`);
    }
    assert.deepEqual(failures, [], failures.join("\n"));
  });

  it("ungültige Eingaben führen nie zu 5xx", async () => {
    assert.ok(config.invalidInputCases.length > 0, "invalidInputCases konfigurieren");
    const obj = await config.createOwnedObject(baseUrl, owner);
    const failures: string[] = [];
    for (const c of config.invalidInputCases) {
      const res = await call(c.method, fill(c.path, obj), owner, c.body);
      if (res.status < 400 || res.status >= 500) failures.push(`${c.method} ${c.path} ${JSON.stringify(c.body)} -> ${res.status}`);
    }
    assert.deepEqual(failures, [], failures.join("\n"));
  });
});

describe("Konfiguration", () => {
  it("CORS lässt fremde Origins nicht zu", async () => {
    const route = protectedRoutes()[0];
    for (const origin of [config.forbiddenOrigin, "null"]) {
      const res = await fetch(baseUrl + fillPath(route.path), {
        method: "OPTIONS",
        headers: { origin, "access-control-request-method": route.method },
      });
      const allowed = res.headers.get("access-control-allow-origin");
      assert.ok(allowed !== origin && allowed !== "*", `CORS erlaubt ${origin}: ${allowed}`);
    }
  });

  it("CORS erlaubt die konfigurierte Origin (Gegenprobe)", async (t) => {
    if (!config.allowedOrigin) return t.skip("keine erlaubte Origin konfiguriert");
    const route = protectedRoutes()[0];
    const res = await fetch(baseUrl + fillPath(route.path), {
      method: "OPTIONS",
      headers: { origin: config.allowedOrigin, "access-control-request-method": route.method },
    });
    assert.equal(res.headers.get("access-control-allow-origin"), config.allowedOrigin);
  });

  it("Fehlerantworten verraten keine Interna", async () => {
    const leakMarker = "geheimer-interner-zustand-4711";
    app.get("/__baseline_boom__", () => {
      throw new Error(leakMarker);
    });
    // Route an den Anfang schieben, damit die Fehlerbehandlung der App dahinter greift.
    const stack = (app as unknown as { router: { stack: unknown[] } }).router.stack;
    stack.unshift(stack.pop());
    try {
      const res = await fetch(`${baseUrl}/__baseline_boom__`);
      const text = await res.text();
      assert.equal(res.status, 500);
      for (const marker of [leakMarker, "Error:", "    at ", "node_modules"]) {
        assert.ok(!text.includes(marker), `Fehlerantwort verrät ${JSON.stringify(marker)}`);
      }
    } finally {
      stack.shift();
    }
  });

  it("Security-Header gesetzt", async (t) => {
    if (!config.expectSecurityHeaders) return t.skip("expectSecurityHeaders=false – UNGEPRÜFT");
    const res = await fetch(baseUrl + (config.publicRoutes[0]?.split(" ")[1] ?? "/"));
    assert.equal(res.headers.get("x-content-type-options"), "nosniff");
    assert.equal(res.headers.get("x-powered-by"), null, "X-Powered-By verrät Express");
  });
});