import { describe, expect, it } from 'vitest';
import { formatRelativeTime } from './relativeTime';

describe('formatRelativeTime', () => {
  const now = new Date('2024-01-10T12:00:00Z');

  it('returns empty string when value is missing', () => {
    expect(formatRelativeTime(null, { now })).toBe('');
  });

  it('returns original value for invalid date strings', () => {
    expect(formatRelativeTime('not-a-date', { now })).toBe('not-a-date');
  });

  it('formats recent timestamps', () => {
    const result = formatRelativeTime('2024-01-10T11:59:30Z', { now, locale: 'en' });
    expect(result).toContain('second');
  });

  it('formats hours ago', () => {
    const result = formatRelativeTime('2024-01-10T11:00:00Z', { now, locale: 'en' });
    expect(result).toBe('1 hour ago');
  });

  it('formats future days', () => {
    const result = formatRelativeTime('2024-01-13T12:00:00Z', { now, locale: 'en' });
    expect(result).toBe('in 3 days');
  });
});