import { describe, it, expect } from 'vitest';
import { createLogger, Logger, maskUserId } from '../../src/utils/logger';

describe('Logger', () => {
  it('createLogger returns a Logger instance', () => {
    const logger = createLogger('test-service');
    expect(logger).toBeInstanceOf(Logger);
  });

  it('info() does not throw', () => {
    const logger = createLogger('test-service');
    expect(() => logger.info('test message')).not.toThrow();
    expect(() => logger.info('with context', { key: 'value' })).not.toThrow();
  });

  it('warn() does not throw', () => {
    const logger = createLogger('test-service');
    expect(() => logger.warn('warning message')).not.toThrow();
    expect(() => logger.warn('with context', { count: 42 })).not.toThrow();
  });

  it('error() does not throw', () => {
    const logger = createLogger('test-service');
    expect(() => logger.error('error message')).not.toThrow();
    expect(() => logger.error('with error', new Error('boom'))).not.toThrow();
    expect(() => logger.error('full', new Error('boom'), { extra: true })).not.toThrow();
  });
});

describe('maskUserId', () => {
  it('masks a normal user ID correctly', () => {
    expect(maskUserId('821596605')).toBe('8215****');
  });

  it('masks a short ID (<=4 chars) as all asterisks', () => {
    expect(maskUserId('1234')).toBe('****');
    expect(maskUserId('abc')).toBe('****');
  });

  it('returns "unknown" for undefined', () => {
    expect(maskUserId(undefined)).toBe('unknown');
  });

  it('returns "unknown" for empty string', () => {
    expect(maskUserId('')).toBe('unknown');
  });

  it('handles numeric input', () => {
    expect(maskUserId(821596605)).toBe('8215****');
  });
});