import type { MaybeComputedRef, UseTimeAgoOptions } from '@vueuse/core'

export const useFormattedDateTime = (
  value: MaybeComputedRef<string | Date | undefined | null>,
  options: Intl.DateTimeFormatOptions = { dateStyle: 'long', timeStyle: 'medium' },
) => {
  const formatter = Intl.DateTimeFormat(undefined, options)
  return computed(() => {
    const v = resolveUnref(value)
    return v ? formatter.format(new Date(v)) : ''
  })
}

export const timeAgoOptions: UseTimeAgoOptions<false> = {
  showSecond: true,
  messages: {
    justNow: 'just now',
    past: n => n,
    future: n => n.match(/\d/) ? `in ${n}` : n,
    month: (n, past) => n === 1
      ? past
        ? 'last month'
        : 'next month'
      : `${n}m`,
    year: (n, past) => n === 1
      ? past
        ? 'last year'
        : 'next year'
      : `${n}y`,
    day: (n, past) => n === 1
      ? past
        ? 'yesterday'
        : 'tomorrow'
      : `${n}d`,
    week: (n, past) => n === 1
      ? past
        ? 'last week'
        : 'next week'
      : `${n} week${n > 1 ? 's' : ''}`,
    hour: n => `${n}h`,
    minute: n => `${n}min`,
    second: n => `${n}s`,
  },
}