import { CoreApiClient, CoreApiClientError } from '../../src/adapters/notification/core-api-client';

describe('CoreApiClient', () => {
  const API_URL = 'http://core.local';
  const CLIENT_ID = 'cid';
  const CLIENT_SECRET = 'csec';

  beforeEach(() => {
    (global as any).fetch = jest.fn();
    jest.clearAllMocks();
  });

  it('requests token successfully and caches it', async () => {
    // token endpoint response
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't1', token_type: 'Bearer', expires_in: 3600 } }) });

    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET });

    const token = await client.getToken();
    expect(token).toBe('t1');

    // second call should not call fetch again for token
    const token2 = await client.getToken();
    expect(token2).toBe('t1');
    expect(global.fetch).toHaveBeenCalledTimes(1);
  });

  it('throws on invalid credentials (401)', async () => {
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 401, json: async () => ({}) });
    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET });
    await expect(client.getToken()).rejects.toThrow(CoreApiClientError);
  });

  it('retries once on 401 during authenticatedRequest', async () => {
    // initial token fetch
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't1', token_type: 'Bearer', expires_in: 3600 } }) });

    // first API call returns 401
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 401, json: async () => ({}) });

    // token refresh fetch returns new token
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't2', token_type: 'Bearer', expires_in: 3600 } }) });

    // retried API call returns 200
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ ok: true }) });

    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET });

    const res = await client.authenticatedRequest(`${API_URL}/api/v1/users`, { method: 'GET' });
    expect(res.status).toBe(200);
    expect(global.fetch).toHaveBeenCalledTimes(4);
  });

  it('does not retry on 403', async () => {
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't1', token_type: 'Bearer', expires_in: 3600 } }) });
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 403, json: async () => ({}) });

    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET });

    const res = await client.authenticatedRequest(`${API_URL}/api/v1/forbidden`, { method: 'GET' });
    expect(res.status).toBe(403);
    // only token fetch + one API call
    expect(global.fetch).toHaveBeenCalledTimes(2);
  });

  it('handles token refresh before expiry', async () => {
    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't1', token_type: 'Bearer', expires_in: 2 } }) });
    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET });

    const token1 = await client.getToken();
    expect(token1).toBe('t1');

    // force expiry by manipulating internal state
    (client as any).tokenExpiry = Date.now() - 1000;

    (global.fetch as jest.Mock).mockResolvedValueOnce({ status: 200, json: async () => ({ success: true, data: { access_token: 't2', token_type: 'Bearer', expires_in: 3600 } }) });

    const token2 = await client.getToken();
    expect(token2).toBe('t2');
  });

  it('handles network timeout', async () => {
    (global.fetch as jest.Mock).mockRejectedValueOnce(Object.assign(new Error('AbortError'), { name: 'AbortError' }));
    const client = new CoreApiClient({ apiUrl: API_URL, clientId: CLIENT_ID, clientSecret: CLIENT_SECRET, timeoutMs: 1 });
    await expect(client.getToken()).rejects.toThrow(CoreApiClientError);
  });
});