// Verificar fechas ISO para el experimento BODYNESS

function getISOWeek(date: Date): { year: number; week: number } {
  const d = new Date(Date.UTC(date.getFullYear(), date.getMonth(), date.getDate()));
  const dayNum = d.getUTCDay() || 7;
  d.setUTCDate(d.getUTCDate() + 4 - dayNum);
  const yearStart = new Date(Date.UTC(d.getUTCFullYear(), 0, 1));
  const weekNum = Math.ceil((((d.getTime() - yearStart.getTime()) / 86400000) + 1) / 7);
  return { year: d.getUTCFullYear(), week: weekNum };
}

function getISOWeekMonday(year: number, week: number): number {
  const jan4 = new Date(Date.UTC(year, 0, 4));
  const dayOfWeek = jan4.getUTCDay() || 7;
  const week1Monday = new Date(Date.UTC(year, 0, 4 - (dayOfWeek - 1)));
  return week1Monday.getTime() + (week - 1) * 7 * 86400000;
}

function getWeeksInYear(year: number): number {
  const dec28 = new Date(Date.UTC(year, 11, 28));
  const iso = getISOWeek(dec28);
  return iso.week;
}

function calculateISOWeekRange(startDate: Date, endDate: Date): {
  numWeeks: number;
  expandedStartTs: number;
  expandedEndTs: number;
  weekKeys: string[];
} {
  const startISO = getISOWeek(startDate);
  const endISO = getISOWeek(endDate);

  const weekKeys: string[] = [];
  let currentYear = startISO.year;
  let currentWeek = startISO.week;

  while (true) {
    const weekKey = `${currentYear}-W${String(currentWeek).padStart(2, '0')}`;
    weekKeys.push(weekKey);

    if (currentYear === endISO.year && currentWeek === endISO.week) {
      break;
    }

    currentWeek++;
    const weeksInYear = getWeeksInYear(currentYear);
    if (currentWeek > weeksInYear) {
      currentWeek = 1;
      currentYear++;
    }
  }

  const expandedStartTs = getISOWeekMonday(startISO.year, startISO.week);
  const expandedEndTs = getISOWeekMonday(endISO.year, endISO.week) + 7 * 86400000;

  return {
    numWeeks: weekKeys.length,
    expandedStartTs,
    expandedEndTs,
    weekKeys,
  };
}

// Experimento: 22 enero - 4 febrero 2026
const startDate = new Date('2026-01-22');
const endDate = new Date('2026-02-04');

console.log('=== Experimento BODYNESS ES ===');
console.log('Start:', startDate.toISOString().split('T')[0], '(day', startDate.getDay(), ')');
console.log('End:', endDate.toISOString().split('T')[0], '(day', endDate.getDay(), ')');
console.log('');

const startISO = getISOWeek(startDate);
const endISO = getISOWeek(endDate);
console.log('Start ISO:', `W${startISO.week}-${startISO.year}`);
console.log('End ISO:', `W${endISO.week}-${endISO.year}`);
console.log('');

const isoRange = calculateISOWeekRange(startDate, endDate);
console.log('ISO Week Range:');
console.log('  numWeeks:', isoRange.numWeeks);
console.log('  weekKeys:', isoRange.weekKeys);
console.log('  expandedStart:', new Date(isoRange.expandedStartTs).toISOString().split('T')[0]);
console.log('  expandedEnd:', new Date(isoRange.expandedEndTs).toISOString().split('T')[0]);
console.log('');

// Verificar cada semana
isoRange.weekKeys.forEach(week => {
  const [year, weekNum] = week.split('-W');
  const monday = getISOWeekMonday(Number(year), Number(weekNum));
  const sunday = monday + 6 * 86400000 + 86399999;
  console.log(`  ${week}: ${new Date(monday).toISOString().split('T')[0]} (Mon) → ${new Date(sunday).toISOString().split('T')[0]} (Sun)`);
});