Google Apps Script for parsing duration strings

parseDuration.gs

/* Based on: https://stackoverflow.com/a/44018490/31493 */

var duration = /(-?\d*\.?\d+(?:e[-+]?\d+)?)\s*([a-zμ]*)/ig

/**
 * conversion ratios
 */



/**
 * convert `str` to ms
 *
 * @param {String} str
 * @return {Number}
 */
function parseDuration(str){
  var result = 0
  var error = null;
  // ignore commas
  str = str.replace(/(\d),(\d)/g, '$1$2')
  if (/^\d+$/.test(str)) result = str*60;
  else if (str.indexOf(':')>=0) {
    var arr = str.split(':')
    if (arr.length != 2) error = true;
    else result = parseInt(arr[0])*60+ parseInt(arr[1])
    
  }
  else if (duration.test(str)) str.replace(duration, function(_, n, units){
    units = getUnits(units)
      || getUnits[units.toLowerCase().replace(/s$/, '')]
      || undefined;
    console.log(n)
    if (typeof units === 'undefined') error = true;
    else result += parseFloat(n, 10) * units;
  })
  else error = true;
  return error ? null : result;
}

function getUnits(unit){
  var to_ret;
  switch(unit){
    case "seconds":
    case "second":
    case "secs":
    case "sec":
    case "s": to_ret = 0; break;
    
    case "minutes":
    case "minute":
    case "mins":
    case "min":
    case "m": to_ret = 1; break;
    
    case "hours":
    case "hour": 
    case "hr":
    case "hrs":
    case "h": to_ret =  60; break;
    
    case "days":
    case "day":
    case "d": to_ret = 24 * 60; break;
    
    case "weeks":
    case "week":
    case "w": to_ret = 7 * 24 * 60; break;
    
    default: to_ret = undefined;
  }
  
  return to_ret;
}

function stripSeconds(str) {
  return str.replaceAll(/\d+s/g, '')
}