export function parseISODate(value: string): Date | undefined {
  if (!isISODate(value)) return undefined

  const [year, month, day] = value.split("-").map(Number)
  return new Date(year!, month! - 1, day)
}

export function toISODate(date: Date): string {
  const year = date.getFullYear()
  const month = String(date.getMonth() + 1).padStart(2, "0")
  const day = String(date.getDate()).padStart(2, "0")
  return `${year}-${month}-${day}`
}

export function formatDate(date: Date, locale?: string): string {
  return new Intl.DateTimeFormat(locale, { dateStyle: "long" }).format(date)
}

export function isISODate(value: string): boolean {
  if (!/^\d{4}-\d{2}-\d{2}$/.test(value)) return false

  const [year, month, day] = value.split("-").map(Number)
  const date = new Date(year!, month! - 1, day)
  return (
    date.getFullYear() === year &&
    date.getMonth() === month! - 1 &&
    date.getDate() === day
  )
}