import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { POST } from '#app/api/revalidate/route';

const { revalidateTag } = vi.hoisted(() => ({ revalidateTag: vi.fn() }));

vi.mock('next/cache', () => ({ revalidateTag }));

const SECRET = 'test-revalidate-secret';

function request({
  secret = SECRET,
  body = JSON.stringify({ tags: ['web-manager'] })
}: { secret?: string | null; body?: string } = {}) {
  const headers = new Headers({ 'content-type': 'application/json' });
  if (secret !== null) {
    headers.set('x-revalidate-secret', secret);
  }

  return new Request('http://web.test/api/revalidate', { method: 'POST', headers, body });
}

beforeEach(() => {
  vi.stubEnv('REVALIDATE_SECRET', SECRET);
  revalidateTag.mockReset();
});

afterEach(() => {
  vi.unstubAllEnvs();
});

describe('authentication', () => {
  it('rejects a request with no secret header', async () => {
    const response = await POST(request({ secret: null }));

    expect(response.status).toBe(401);
    expect(revalidateTag).not.toHaveBeenCalled();
  });

  it('rejects a wrong secret', async () => {
    const response = await POST(request({ secret: 'wrong' }));

    expect(response.status).toBe(401);
    expect(revalidateTag).not.toHaveBeenCalled();
  });

  it('rejects everything when the server has no secret configured — even a matching empty header', async () => {
    vi.stubEnv('REVALIDATE_SECRET', '');

    expect((await POST(request({ secret: '' }))).status).toBe(401);
    expect((await POST(request())).status).toBe(401);
    expect(revalidateTag).not.toHaveBeenCalled();
  });
});

describe('payload validation', () => {
  it('rejects a body that is not JSON', async () => {
    const response = await POST(request({ body: 'not json {' }));

    expect(response.status).toBe(400);
    expect(await response.json()).toEqual({ message: 'Invalid JSON body' });
  });

  it.each([
    ['a non-object payload', JSON.stringify('tags')],
    ['a null payload', JSON.stringify(null)],
    ['a missing tags field', JSON.stringify({})],
    ['tags that are not an array', JSON.stringify({ tags: 'web-manager' })],
    ['an empty tags array', JSON.stringify({ tags: [] })],
    ['a non-string tag', JSON.stringify({ tags: ['ok', 7] })],
    ['an empty-string tag', JSON.stringify({ tags: [''] })]
  ])('rejects %s with 400', async (_label, body) => {
    const response = await POST(request({ body }));

    expect(response.status).toBe(400);
    expect(revalidateTag).not.toHaveBeenCalled();
  });

  it('accepts exactly 50 tags but rejects 51', async () => {
    const fifty = Array.from({ length: 50 }, (_, i) => `tag-${i}`);

    expect((await POST(request({ body: JSON.stringify({ tags: fifty }) }))).status).toBe(200);
    expect(
      (await POST(request({ body: JSON.stringify({ tags: [...fifty, 'one-more'] }) }))).status
    ).toBe(400);
  });

  it('accepts a 256-character tag but rejects 257', async () => {
    expect(
      (await POST(request({ body: JSON.stringify({ tags: ['a'.repeat(256)] }) }))).status
    ).toBe(200);
    expect(
      (await POST(request({ body: JSON.stringify({ tags: ['a'.repeat(257)] }) }))).status
    ).toBe(400);
  });
});

describe('revalidation', () => {
  it('revalidates every tag with the max profile and echoes them back', async () => {
    const tags = ['web-manager', 'web-manager:page:en:about'];
    const response = await POST(request({ body: JSON.stringify({ tags }) }));

    expect(response.status).toBe(200);
    expect(await response.json()).toEqual({ revalidated: tags });
    expect(revalidateTag).toHaveBeenCalledTimes(2);
    expect(revalidateTag).toHaveBeenNthCalledWith(1, 'web-manager', 'max');
    expect(revalidateTag).toHaveBeenNthCalledWith(2, 'web-manager:page:en:about', 'max');
  });
});