Simplifying ISO 8601 Date Handling in Effect Typescript

const Iso8601Date = S.String.pipe(
  S.pattern(/^(\d{4})-(\d{2})-(\d{2})$/),
  S.transformOrFail(
    S.DateTimeUtcFromSelf,
    {
      decode: (input, _, ast) => {
        const match = input.match(/^(\d{4})-(\d{2})-(\d{2})$/)!
        const [, yearStr, monthStr, dayStr] = match
        
        const dateOption = DateTime.make(
          { year: Number(yearStr), month: Number(monthStr), day: Number(dayStr) }
        )
        
        return Option.match(dateOption, {
          onNone: () => ParseResult.fail(new ParseResult.Type(ast, input)),
          onSome: (date) => ParseResult.succeed(date)
        })
      },
      encode: (dateTime) => {
        const { year, month, day } = DateTime.toParts(dateTime)
        return ParseResult.succeed(
          `${year.toString().padStart(4, '0')}-${month.toString().padStart(2, '0')}-${day.toString().padStart(2, '0')}`
        )
      }
    }
  )
)