Fuzzy Humanize date using Moment.js for datatable searching

Question

In my JS project, I am using datatable plugin to show data where I have a date column which users can filter/search.

In order to help users to search using a logical string such as today, thismonth , lastweek I am writting a fucntion which uses MomentJs.

I am looking at the most efficient way of writing this fuzzyDate function.

function fuzzyDate(mydate){
  var fuzzy1 = ''; var fuzzy2 = ''; var fuzzy3 = '';

  var todaydt = moment(moment().format('YYYY-MM-DD'));
  var daydiff = mydate.diff(todaydt,'day');
  if (daydiff==-1){fuzzy1='Yesterday'}
  if (daydiff==0){fuzzy1='Today'}
  if (daydiff==1){fuzzy1='Tomorrow'}

  var weekdiff = mydate.diff(todaydt,'week');
  if (weekdiff==-1){fuzzy2='LastWeek'}
  if (weekdiff==0){fuzzy2='ThisWeek'}
  if (weekdiff==1){fuzzy2='NextWeek'}

  var monthdiff = mydate.diff(todaydt,'month');
  if (monthdiff==-1){fuzzy3='LastMonth'}
  if (monthdiff==0){fuzzy3='ThisMonth'}
  if (monthdiff==1){fuzzy3='NextMonth'}

  return fuzzy1 + ' ' + fuzzy2 + ' ' + fuzzy3;
}

console.log( '2018-06-01 - ', fuzzyDate(moment('2018-06-01','YYYY-MM-DD')) ) ;
console.log( '2018-07-01 - ', fuzzyDate(moment('2018-07-01','YYYY-MM-DD')) ) ;
console.log( '2018-07-07 - ', fuzzyDate(moment('2018-07-07','YYYY-MM-DD')) ) ;
console.log( '2018-07-10 - ', fuzzyDate(moment('2018-07-10','YYYY-MM-DD')) ) ;
console.log( '2018-07-11 - ', fuzzyDate(moment('2018-07-11','YYYY-MM-DD')) ) ;
console.log( '2018-07-12 - ', fuzzyDate(moment('2018-07-12','YYYY-MM-DD')) ) ;
console.log( '2018-07-13 - ', fuzzyDate(moment('2018-07-13','YYYY-MM-DD')) ) ;
console.log( '2018-07-15 - ', fuzzyDate(moment('2018-07-15','YYYY-MM-DD')) ) ;
console.log( '2018-07-30 - ', fuzzyDate(moment('2018-07-30','YYYY-MM-DD')) ) ;
console.log( '2018-08-30 - ', fuzzyDate(moment('2018-08-30','YYYY-MM-DD')) ) ;

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.22.2/moment.min.js"></script>

Output of the above function

2018-06-01 - LastMonth
2018-07-01 - LastWeek ThisMonth
2018-07-07 - ThisWeek ThisMonth
2018-07-10 - ThisWeek ThisMonth
2018-07-11 - Yesterday ThisWeek ThisMonth
2018-07-12 - Today ThisWeek ThisMonth
2018-07-13 - Tomorrow ThisWeek ThisMonth
2018-07-15 - ThisWeek ThisMonth
2018-07-30 - ThisMonth
2018-08-30 - NextMonth

Answer 1

What if you have three functions that each calculate the string on its own? Therefore:

function days_diff(daydiff) {
  if (daydiff==0) return 'Today'
  if (daydiff==1) return 'Tomorrow'
  if (daydiff==-1) return 'Yesterday'
  return null
}
function weeks_diff(daydiff) {
  if (daydiff > 0 && daydiff < 7) return 'Thisweek'
  if (daydiff < 7) return 'Nextweek'
  return null
  ...

Then you can have your one aggregate function that calls the three of them...

Here's the much more complicated one from Rails that might provide guidance/inspiration: https://github.com/rails/rails/blob/2c97fbf6503c9199f3fe5ed06222e7226dc6fcd9/actionview/lib/action_view/helpers/date_helper.rb#L104