Regex validation for time tracking

Question

I am trying to validate a string the way it is done in Jira in Javascript. I'm trying to replicate how it is validated in Jira. I am guessing I could do this with Regex but I am not sure how.

A user can type a string in the format of "1d 6h 30m" which would mean 1 day, 6 hours, 30 minutes. I do not need the weeks for my use case. I want to show an error if the user uses an invalid character (anything except 'd','h','m', or ' '). Also the string must separate the time durations by spaces and ideally I would like to force the user to enter the time durations in descending order meaning '6h 1d' would be invalid because the days should come first. Also the user does not have to enter all information so '30m' would be valid.

This is my code for getting the days, hours and minutes which seems to work. I just need help with the validation part.

let time = '12h 21d 30m'; //example
let times = time.split(' ');
let days = 0;
let hours = 0;
let min = 0;
for(let i = 0; i < times.length; i++) {
    if (times[i].includes('d')){
        days = times[i].split('d')[0];
    }
    if (times[i].includes('h')){
        hours = times[i].split('h')[0];
    }
    if (times[i].includes('m')){
        min = times[i].split('m')[0];
    }
}
console.log(days);
console.log(hours);
console.log(min);

Answer 1

const INPUT = "12h 21d  30s";

checkTimespanFormat(INPUT);

if (checkTimespanKeysOrder(INPUT, true))
  console.log(`${INPUT} keys order is valid`);
else console.log(`${INPUT} keys order is NOT valid`);
//******************************************************************

/**
 * Ensures that time keys are:
 * - Preceeded by one or two digits
 * - Separated by one or many spaces
 */
function checkTimespanFormat(timespanStr, maltiSpacesSeparation = false) {
  // timespan items must be separated by 1 space
  if (maltiSpacesSeparation) timespanStr = timespanStr.toLowerCase().split(" ");
  // timespan items must be separated by one or many space
  else timespanStr = timespanStr.toLowerCase().split(/ +/);

  // timespan items must be formatted correctly
  timespanStr.forEach((item) => {
    if (!/^\d{1,2}[dhms]$/.test(item)) console.log("invalid", item);
    else console.log("valid", item);
  });
}

/**
 * Validates:
 * - Keys order
 * - Duplicate keys
 */
function checkTimespanKeysOrder(timespanStr) {
  const ORDER = ["d", "h", "m", "s"];

  let timeKeysOrder = timespanStr
    .replace(/[^dhms]/g, "") // Removing non time keys characters
    .split("") // toArray
    .map((char) => {
      return ORDER.indexOf(char); // Getting the order of time keys
    });

  for (i = 0; i < timeKeysOrder.length - 1; i++)
    if (timeKeysOrder.at(i) >= timeKeysOrder.at(i + 1)) return false;
  return true;
}