import { describe, it, before, after, beforeEach } from 'node:test';
import assert from 'node:assert/strict';
import Koa from 'koa';
import bodyParser from 'koa-bodyparser';
import supertest from 'supertest';
import { rateLimit } from '../middleware/ratelimit.js';

describe('rateLimit 中间件', () => {
  let app, agent;

  before(() => {
    app = new Koa();
    app.use(bodyParser());
    app.use(rateLimit(3, 60_000));
    app.use(async (ctx) => {
      ctx.body = { ok: true };
    });
    agent = supertest(app.callback());
  });

  it('前3次请求应正常通过', async () => {
    for (let i = 0; i < 3; i++) {
      const res = await agent.post('/test').send({});
      assert.equal(res.status, 200);
      assert.equal(res.body.ok, true);
    }
  });

  it('第4次请求应被限流', async () => {
    const res = await agent.post('/test').send({});
    assert.equal(res.status, 200); // HTTP 200，业务码 429
    assert.equal(res.body.code, 429);
    assert.ok(res.body.msg.includes('请求过于频繁'));
    assert.ok(res.headers['retry-after']);
  });

  it('限流响应头应包含 X-RateLimit 信息', async () => {
    // 新建一个不受之前计数影响的中间件（不同限流阈值 + 不同路径）
    const freshApp = new Koa();
    freshApp.use(bodyParser());
    freshApp.use(rateLimit(100, 60_000));
    freshApp.use(async (ctx) => { ctx.body = { ok: true }; });
    const freshAgent = supertest(freshApp.callback());

    const res = await freshAgent.post('/headercheck').send({});
    assert.equal(res.headers['x-ratelimit-limit'], '100');
    assert.equal(res.headers['x-ratelimit-remaining'], '99');
  });
});