Generating Time Slots using Moment Js

I have Object structured like this

var x = {
    nextSlot: 30,
    breakTime: [
        ['11:00', '14:00'], ['16:00', '18:00']
    ],
    startTime: '8:00',
    endTime: '20:00'
}

I want to geneate time slots , starting from startTime till endTime. But i dont want to consider breakTime in timeslot. Output should be

['08:00','08:30','09:00','09:30','10:00','10:30','14:00','14:30','15:00','15:30', '17:30', '18:00', '18:30','19:00','19:30']

I implemented my own logic. But that works on;y for the breaktime array of length 1.

// Check whether the startTime is less than endTime
while (moment(x.startTime, ['HH:mm']).format('HH:mm') < moment(x.endTime, ['HH:mm']).format('HH:mm')) {
    for (let i = 0; i < x.breakTime.length; i++) {
        // if startTime is greater then breakTime[i][0], and if starttime is less then breaktime[i][1], 
        //just add nextSlot to starttime 
        if (moment(x.startTime, ['HH:mm']).format('HH:mm') >= moment(x.breakTime[i][0], ['HH:mm']).format('HH:mm') && moment(x.startTime, ['HH:mm']).format('HH:mm') < moment(x.breakTime[i][1], ['HH:mm']).format('HH:mm')) {
            x.startTime = moment(x.startTime, ['HH:mm']).add(x.nextSlot, 'm').format('HH:mm');
        } else {
        //otherwise, push the time to slot array and then increment it by nextSlot 
            slots.push(moment(x.startTime, ['HH:mm']).format('hh:mm'));
            x.startTime = moment(x.startTime, ['HH:mm']).add(x.nextSlot, 'm').format('HH:mm');
        }
    }
}

This doesn't work if i add one more array element to breakTime.

Solution

Something like this should work:

var x = {
    nextSlot: 30,
    breakTime: [
        ['11:00', '14:00'], ['16:00', '18:00']
    ],
    startTime: '8:00',
    endTime: '20:00'
};

var slotTime = moment(x.startTime, "HH:mm");
var endTime = moment(x.endTime, "HH:mm");

function isInBreak(slotTime, breakTimes) {
    return breakTimes.some((br) => {
      return slotTime >= moment(br[0], "HH:mm") && slotTime < moment(br[1], "HH:mm");
  });
}

let times = [];
while (slotTime < endTime)
{
  if (!isInBreak(slotTime, x.breakTime)) {
     times.push(slotTime.format("HH:mm"));
  }
  slotTime = slotTime.add(x.nextSlot, 'minutes');
}

console.log("Time slots: ", times);

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