import { describe, expect, it } from 'vitest'
import { formatDate, formatTime } from '../datetime-format'

describe('datetime-format', () => {
  it('returns an empty string for an empty format', () => {
    const date = new Date(2026, 2, 15, 0, 5, 9)
    expect(formatDate(date, '')).toBe('')
    expect(formatTime(date, '')).toBe('')
  })

  it('formats dates and times with shared helpers', () => {
    const date = new Date(2026, 2, 15, 14, 5, 9)

    expect(formatDate(date, 'YYYY-MM-DD')).toBe('2026-03-15')
    expect(formatDate(date, 'dddd, MMMM D, YYYY')).toBe('Sunday, March 15, 2026')
    expect(formatTime(date, 'HH:mm')).toBe('14:05')
    expect(formatTime(date, 'h:mm A')).toBe('2:05 PM')
  })

  it('formats every date token without token-order collisions', () => {
    const date = new Date(2026, 0, 5, 0, 5, 9)
    expect(formatDate(date, 'YYYY YY MMMM MMM MM M dddd ddd DD D')).toBe(
      '2026 26 January Jan 01 1 Monday Mon 05 5',
    )
  })

  it.each([
    [1, '1st'], [2, '2nd'], [3, '3rd'], [4, '4th'],
    [11, '11th'], [12, '12th'], [13, '13th'],
    [21, '21st'], [22, '22nd'], [23, '23rd'], [30, '30th'], [31, '31st'],
  ])('formats ordinal day %s as %s', (day, ordinal) => {
    const date = new Date(2025, 0, day)
    expect(formatDate(date, 'MMMM Do, YYYY')).toBe(`January ${ordinal}, 2025`)
    expect(formatDate(date, 'Do D DD')).toBe(`${ordinal} ${day} ${String(day).padStart(2, '0')}`)
  })

  it('formats both twelve-hour periods and every time token', () => {
    const morning = new Date(2026, 0, 5, 0, 5, 9)
    const evening = new Date(2026, 0, 5, 23, 15, 42)
    expect(formatTime(morning, 'HH H hh h mm m ss s A a')).toBe('00 0 12 12 05 5 09 9 AM am')
    expect(formatTime(evening, 'HH H hh h mm m ss s A a')).toBe('23 23 11 11 15 15 42 42 PM pm')
  })
})