import { describe, it, expect } from 'vitest';
import express from 'express';
import request from 'supertest';
import { z } from 'zod';
import { validate } from '../../lib/api/validate.js';
import { errorMiddleware } from '../../lib/api/errors.js';
import { parsePagination } from '../../lib/api/pagination.js';

function buildApp() {
  const app = express();
  app.use(express.json());

  app.post('/body',
    validate({ body: z.object({ name: z.string().min(1) }) }),
    (req, res) => res.json(req.body)
  );

  app.get('/params/:id',
    validate({ params: z.object({ id: z.string().uuid() }) }),
    (req, res) => res.json(req.params)
  );

  app.get('/page', (req, res) => {
    try {
      const p = parsePagination(req);
      res.json(p);
    } catch (e) { errorMiddleware(e, req, res, () => {}); }
  });

  app.use(errorMiddleware);
  return app;
}

describe('api/validate', () => {
  it('body schema parses and replaces req.body', async () => {
    const res = await request(buildApp()).post('/body').send({ name: 'home' });
    expect(res.status).toBe(200);
    expect(res.body).toEqual({ name: 'home' });
  });

  it('body schema failure → 400 with zod issues in details', async () => {
    const res = await request(buildApp()).post('/body').send({ name: '' });
    expect(res.status).toBe(400);
    expect(res.body.error.code).toBe('validation_failed');
    expect(Array.isArray(res.body.error.details)).toBe(true);
    expect(res.body.error.details.length).toBeGreaterThan(0);
  });

  it('params schema failure → 400', async () => {
    const res = await request(buildApp()).get('/params/not-a-uuid');
    expect(res.status).toBe(400);
  });
});

describe('api/pagination', () => {
  it('defaults to limit=50 offset=0', async () => {
    const res = await request(buildApp()).get('/page');
    expect(res.body).toEqual({ limit: 50, offset: 0 });
  });

  it('honors ?limit&offset', async () => {
    const res = await request(buildApp()).get('/page?limit=10&offset=5');
    expect(res.body).toEqual({ limit: 10, offset: 5 });
  });

  it('rejects negative offset', async () => {
    const res = await request(buildApp()).get('/page?offset=-1');
    expect(res.status).toBe(400);
  });

  it('rejects limit above max', async () => {
    const res = await request(buildApp()).get('/page?limit=999');
    expect(res.status).toBe(400);
  });
});