create a function that can parse a date or datetime with different source formats including american standards and iso 8601 in javascript

index.tsx
function parseDateTime(dateTimeString) {
  // First, check if the input is already a date object
  if (Object.prototype.toString.call(dateTimeString) === '[object Date]') {
    return dateTimeString;
  }
  
  // Define regular expressions to match different date formats
  const amRegex = /^(\d{1,2})\/(\d{1,2})\/(\d{4}) (\d{1,2}):(\d{2}):(\d{2}) (AM|PM)$/;
  const isoRegex = /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})\.(\d{3})Z$/;
  
  // Try parsing the input using the American date format first
  let match = dateTimeString.match(amRegex);
  if (match) {
    const [, month, day, year, hours, minutes, seconds, amPm] = match;
    const adjustedHours = (hours % 12) + ((amPm === 'PM') ? 12 : 0);
    return new Date(year, month - 1, day, adjustedHours, minutes, seconds);
  }
  
  // If that fails, try parsing using the ISO 8601 format
  match = dateTimeString.match(isoRegex);
  if (match) {
    const [, year, month, day, hours, minutes, seconds, milliseconds] = match;
    return new Date(Date.UTC(year, month - 1, day, hours, minutes, seconds, milliseconds));
  }
  
  // If all else fails, return NaN to indicate an error
  return NaN;
}
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index.tsx
const date1 = parseDateTime('02/14/2022 10:30:00 AM'); // returns a Date object representing February 14, 2022 at 10:30:00 AM
const date2 = parseDateTime('2022-02-14T10:30:00.000Z'); // also returns a Date object representing the same datetime
const date3 = parseDateTime('not a valid date'); // returns NaN to indicate an error
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