dates.js

export function calculateRevisionDates(dateString) {
  const [year, month, day] = dateString.split("-").map(Number);
  const addWeeks = (y, m, d, weeks) => {
    const date = new Date(Date.UTC(y, m - 1, d + weeks * 7));
    return formatDate(date);
  };
  const addMonths = (y, m, d, months) => {
    const date = new Date(Date.UTC(y, m - 1 + months, d));
    return formatDate(date);
  };
  return [
    addWeeks(year, month, day, 1),
    addMonths(year, month, day, 1),
    addMonths(year, month, day, 3),
    addMonths(year, month, day, 6),
    addMonths(year, month, day, 12),
  ];
}

export function formatDate(date) {
  const y = date.getUTCFullYear();
  const m = String(date.getUTCMonth() + 1).padStart(2, "0");
  const d = String(date.getUTCDate()).padStart(2, "0");
  return `${y}-${m}-${d}`;
}

export function stringifiedTodayDate() {
  const today = new Date();
  const year = today.getFullYear();
  const month = String(today.getMonth() + 1).padStart(2, "0");
  const day = String(today.getDate()).padStart(2, "0");
  return `${year}-${month}-${day}`;
}

export function upcomingItems(agendaItems) {
  const today = stringifiedTodayDate();
  const upcomingItems = agendaItems.filter((agendaItem) => {
    return agendaItem.date >= today;
  });
  const sortedUpcomingItems = upcomingItems.toSorted((a, b) => {
    return a.date.localeCompare(b.date);
  });
  return sortedUpcomingItems;
}