import { describe, expect, it, vi } from 'vitest';

import { ApiError, request } from '@/api/client';

function jsonResponse(body: unknown, status = 200): Response {
  return new Response(JSON.stringify(body), {
    status,
    headers: { 'Content-Type': 'application/json' },
  });
}

describe('api client', () => {
  it('returns the parsed payload on success', async () => {
    const fetchMock = vi.fn().mockResolvedValue(jsonResponse({ api_version: 'v1' }));
    vi.stubGlobal('fetch', fetchMock);

    await expect(request<{ api_version: string }>('/meta')).resolves.toEqual({
      api_version: 'v1',
    });
    expect(fetchMock).toHaveBeenCalledWith(
      '/api/v1/meta',
      expect.objectContaining({ method: 'GET', credentials: 'same-origin' }),
    );
  });

  it('maps the server error envelope to ApiError', async () => {
    vi.stubGlobal(
      'fetch',
      vi
        .fn()
        .mockResolvedValue(
          jsonResponse({ error: { code: 'perm.denied', message: 'no access' } }, 403),
        ),
    );

    await expect(request('/guilds/1')).rejects.toMatchObject({
      name: 'ApiError',
      code: 'perm.denied',
      status: 403,
    });
  });

  it('falls back to internal.error when the body is not an envelope', async () => {
    vi.stubGlobal(
      'fetch',
      vi.fn().mockResolvedValue(new Response('gateway timeout', { status: 504 })),
    );

    const error = await request('/meta').catch((reason: unknown) => reason);
    expect(error).toBeInstanceOf(ApiError);
    expect((error as ApiError).code).toBe('internal.error');
    expect((error as ApiError).status).toBe(504);
  });

  it('sends a json body for write requests', async () => {
    const fetchMock = vi.fn().mockResolvedValue(jsonResponse({ ok: true }));
    vi.stubGlobal('fetch', fetchMock);

    await request('/guilds', { method: 'POST', body: { name: 'test' } });

    const init = fetchMock.mock.calls[0]?.[1] as RequestInit;
    expect(init.body).toBe('{"name":"test"}');
    expect((init.headers as Record<string, string>)['Content-Type']).toBe('application/json');
  });
});