import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import { consume, _resetMemoryBuckets, clientIp } from "./ratelimit";

describe("memory rate limiter", () => {
  beforeEach(() => {
    _resetMemoryBuckets();
    vi.useFakeTimers();
    vi.setSystemTime(new Date(0));
  });
  afterEach(() => {
    vi.useRealTimers();
  });

  it("allows requests under the limit", async () => {
    const r1 = await consume("k", 3, 1000);
    const r2 = await consume("k", 3, 1000);
    const r3 = await consume("k", 3, 1000);
    expect(r1.ok).toBe(true);
    expect(r2.ok).toBe(true);
    expect(r3.ok).toBe(true);
    expect(r3.remaining).toBe(0);
  });

  it("rejects the request that exceeds the limit", async () => {
    await consume("k", 2, 1000);
    await consume("k", 2, 1000);
    const r3 = await consume("k", 2, 1000);
    expect(r3.ok).toBe(false);
    expect(r3.remaining).toBe(0);
  });

  it("resets the bucket after the window elapses", async () => {
    await consume("k", 1, 1000);
    const blocked = await consume("k", 1, 1000);
    expect(blocked.ok).toBe(false);

    vi.advanceTimersByTime(1001);

    const allowed = await consume("k", 1, 1000);
    expect(allowed.ok).toBe(true);
  });

  it("isolates buckets by key", async () => {
    await consume("a", 1, 1000);
    const a2 = await consume("a", 1, 1000);
    const b1 = await consume("b", 1, 1000);
    expect(a2.ok).toBe(false);
    expect(b1.ok).toBe(true);
  });

  it("returns a sensible resetAt timestamp", async () => {
    const r = await consume("k", 5, 1000);
    expect(r.resetAt).toBe(1000);
  });
});

describe("clientIp", () => {
  it("trusts the first hop in x-forwarded-for", () => {
    const h = new Headers({ "x-forwarded-for": "1.2.3.4, 5.6.7.8" });
    expect(clientIp(h)).toBe("1.2.3.4");
  });

  it("falls back to x-real-ip", () => {
    const h = new Headers({ "x-real-ip": "9.9.9.9" });
    expect(clientIp(h)).toBe("9.9.9.9");
  });

  it("returns 'unknown' when no header is present", () => {
    expect(clientIp(new Headers())).toBe("unknown");
  });
});