import base from './base';
import _fs from 'fs';

jest.mock('fs');

const fs: jest.Mocked<typeof _fs> = _fs as any;

class ErrnoException extends Error {
  constructor(public code: string, public message = '') {
    super(message);
    Object.setPrototypeOf(this, ErrnoException.prototype);
  }
}

describe('base', () => {
  describe('read', () => {
    describe('when file exists', () => {
      beforeEach(() => {
        // @ts-ignore until fixed
        fs.readFile.mockImplementation((_path, options, callback) => {
          if (typeof options === 'string' && options === 'utf8') {
            callback(
              null,
              Buffer.from(JSON.stringify({ phone: '5555555555' }), options)
            );
          }
        });
      });

      it('reads the file', async () => {
        expect(
          await base.read<{ phone: '5555555555' }>('users', '5555555555')
        ).toEqual({
          phone: '5555555555'
        });
        expect(fs.readFile).toHaveBeenCalled();
      });
    });
    describe('when file does not exist', () => {
      beforeEach(() => {
        // @ts-ignore until fixed
        fs.readFile.mockImplementation((_path, _options, callback) => {
          callback(new ErrnoException('ENOENT'));
        });
      });

      it('throws an error', () => {
        expect(base.read('users', '5555555555')).rejects.toEqual(
          expect.objectContaining({ code: 'ENOENT' })
        );
        expect(fs.readFile).toHaveBeenCalled();
      });
    });
  });
});