createTimes.js

const moment = require("moment");

// weekly meetings, begining at startDate
function createDates(startDate, n) {
    const dates = [];
    const m = moment(startDate);
    for (var i = 0; i < n; i++) {
        m.add(7, "days");
        dates.push(m.format("DD.MM.YYYY"));
    }
    return dates;
}

// meeting slots, with an added buffer and lunch break
function createSlots(
    startSlot,
    n,
    opts = { duration: 60, buffer: 20, lunch: 30 }
) {
    const { duration, buffer, lunch } = opts;
    const slots = [];
    let end = moment(startSlot, "HH:mm");
    for (var i = 0; i < n; i++) {
        let start = moment(end);
        end.add(duration, "m");
        // print slot duration
        slots.push(`${start.format("HH:mm")} – ${end.format("HH:mm")}`);
        end.add(buffer, "m");
        // add lunch break
        if (start.hour() < 12 && end.hour() > 12) {
            end.add(lunch, "m");
        }
    }
    return slots;
}

module.exports = {
    createDates,
    createSlots
};