Calculate estimated shipping date based on predefined interval, excluding weekends and holidays

dynamic-delivery-date.liquid

<script>
  // Calculate the sequence number of the holidays here: https://miniwebtool.com/day-of-the-year-calculator/
  // function to check leap year
  function checkLeapYear(year) {
    const isLeap = new Date(year, 1, 29).getDate() === 29;
    return isLeap;
  }

  const currentYear = new Date().getFullYear();
  if (checkLeapYear(currentYear)) {
    const PUBLIC_HOLIDAYS_DAYS = [1,97,100,122,140,150,277,317,360,361];
  } else {
    const PUBLIC_HOLIDAYS_DAYS = [1,97,100,121,139,149,276,316,359,360];
  }
  
  const dateFormatConnector = '{{ "products.product.date_format_connector" | t }}';

  function calcWithHolidays(holidays, today, total) {
    var finalTotal = total;
    var futureDate = today + total;
    for (let i = today; i <= futureDate; i++) {
      if (holidays.includes(i)) {
        finalTotal++;
      }
    }
    return finalTotal
  }

  function getShortDayName(day) {
    const dayNumber = day.getDay();
    const shortDayNames = ['So', 'Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa'];
    return shortDayNames[dayNumber];
  }

  function getFullDayName(day) {
    const dayNumber = day.getDay();
    const longDayNames = ['Sonntag', 'Montag', 'Dienstag', 'Mittwoch', 'Donnerstag', 'Freitag', 'Sonnabend'];
    return longDayNames[dayNumber];
  }

  function getShortMonthName(day) {
    const monthNumber = day.getMonth();
    const shortMonthNames = ['Jan', 'Feb', 'Mär', 'Apr', 'Mai', 'Jun', 'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dez'];
    return shortMonthNames[monthNumber];
  }

  function getFullMonthName(day) {
    const monthNumber = day.getMonth();
    const shortMonthNames = ['Januar', 'Februar', 'März', 'April', 'Mai', 'Juni', 'Juli', 'August', 'September', 'Oktober', 'November', 'Dezember'];
    return shortMonthNames[monthNumber];
  }

  function calculateDate() {
    // define which class to alter
    const className = "dynamic-date";

    // start with today
    const today = new Date();
    var hours = today.getHours();
    var extraDay = hours < 12 ? 0 : 1;
    var start = new Date(today.getFullYear(), 0, 0);
    var diff = today - start;
    var oneDay = 1000 * 60 * 60 * 24;
    var day = Math.floor(diff / oneDay);
    console.log(day);
    console.log(hours);

    const currentDayOfWeekNumber = today.getDay();

    // skip over weekend logic

    // Monday -> Tuesday, Tuesday -> Wednesday, Wedneday -> Friday
    let futureTotalDays = 2;
    let calcFutureTotalDays;

    // Thursday -> Monday
    if (currentDayOfWeekNumber === 4 ) {
      futureTotalDays = 4;
      calcFutureTotalDays = calcWithHolidays(PUBLIC_HOLIDAYS_DAYS, day, futureTotalDays);
      futureTotalDays = Math.max(futureTotalDays, calcFutureTotalDays);
    }
    // Friday -> Monday
    else if (currentDayOfWeekNumber === 5 ) {
      futureTotalDays = 3;
      calcFutureTotalDays = calcWithHolidays(PUBLIC_HOLIDAYS_DAYS, day, futureTotalDays);
      futureTotalDays = Math.max(futureTotalDays, calcFutureTotalDays);
    }
    // Saturday -> Monday
    else if (currentDayOfWeekNumber === 6 ) {
      futureTotalDays = 2;
      calcFutureTotalDays = calcWithHolidays(PUBLIC_HOLIDAYS_DAYS, day, futureTotalDays);
      futureTotalDays = Math.max(futureTotalDays, calcFutureTotalDays);
    }
    // Saturday -> Tuesday
    else if (currentDayOfWeekNumber === 0 ) {
      futureTotalDays = 1;
      calcFutureTotalDays = calcWithHolidays(PUBLIC_HOLIDAYS_DAYS, day, futureTotalDays);
      futureTotalDays = Math.max(futureTotalDays, calcFutureTotalDays);
    }

    // Calculate Future Delivery Date
    const futureDate = new Date(today.getTime() + ((futureTotalDays + extraDay) * 24 * 60 * 60 * 1000));

    // Get the day, month, and year of the Future Delivery day
    const shortDayName = getShortDayName(futureDate);
    const longDayName = getFullDayName(futureDate);
    const month = getFullMonthName(futureDate);
    const date = futureDate.getDate();

    let content = `${longDayName}${dateFormatConnector}${date}. ${month}`;


    // get the element with the "date" id
    var dateElements = Array.from(document.querySelectorAll("." + className));

    for (const dateElement of dateElements) {
      // set the text of the paragraph element to the day and date
      dateElement.textContent = content
    }

    console.log("Set the content of " + dateElements.length + " elements with class " + className + " to", content)
  }


  setInterval(() => {
    calculateDate();
  }, 100)
</script>