Given a Gregorian Date, get the Broadcast Date Ranges for Week, Month, Quarter, and Year

getBroadcastDateRange.js

(function (url, onLoad) {
    var script = document.createElement('script');
    script.addEventListener('load', onLoad);
    script.src = url;
    document.getElementsByTagName('head')[0].appendChild(script);
}('https://cdn.jsdelivr.net/npm/[email protected]/moment.min.js', function () {
    
    const fmt = 'MM/DD/YYYY';

    function getBroadcastWeek(momentDate) {
      let date = momentDate.clone();
      let day = date.day();

      // Find the closest Monday <= the date
      let start = moment(date).subtract((day + 6) % 7, 'day');

      // Find the closest Sunday >= the date
      let end = moment(date).add((7 - day) % 7, 'day');

      return { start, end };
    }

    function getBroadcastMonth(momentDate) {
      // Given the start of the Gregorian month is always included in the start of the
      // broadcast month, we can use the broadcast week method to find it.
      let startDate = momentDate.clone().startOf('month');

      // The broadcast end date in the month is always the last Sunday of the month
      let endDate = momentDate.clone().endOf('month');

      let { start } = getBroadcastWeek(startDate);
      let end = endDate.subtract(endDate.day(), 'day');

      return { start, end };
    }

    function getBroadcastQuarter(momentDate) {
      // Given that a broadcast first of month always contains the gregorian first of the month, each
      // first day in a broadcast quarter contains the first day in the gregorian quarter.
      let { end: date } = getBroadcastWeek(momentDate.clone());
      let { start } = getBroadcastWeek(date.startOf('quarter'));
      let { end } = getBroadcastMonth(date.add(2, 'months'));

      return { start, end };
    }

    function getBroadcastYear(momentDate) {
      // Similar logic. We use the start of the month to get broadcast dates
      let { start } = getBroadcastWeek(momentDate.clone().startOf('year'));
      let { end } = getBroadcastMonth(momentDate.clone().month(11).startOf('month'));

      return { start, end };
    }

    // TEST
    let date = moment('01/11/2018', fmt);

    let { start: weekStart, end: weekEnd } = getBroadcastWeek(date);
    let { start: monthStart, end: monthEnd } = getBroadcastMonth(date);
    let { start: quarterStart, end: quarterEnd } = getBroadcastQuarter(date);
    let { start: yearStart, end: yearEnd } = getBroadcastYear(date);

    console.log('Date:', date.format(fmt));

    console.log('Broadcast Week:', weekStart.format(fmt), '->', weekEnd.format(fmt));
    console.log('Broadcast Month:', monthStart.format(fmt), '->', monthEnd.format(fmt));
    console.log('Broadcast Quarter:', quarterStart.format(fmt), '->', quarterEnd.format(fmt));
    console.log('Broadcast Year:', yearStart.format(fmt), '->', yearEnd.format(fmt));
}))

Just some limited testing. Hopefully it's correct based on https://en.wikipedia.org/wiki/Broadcast_calendar