Date Arithmetic

// Method 1: Add/subtract days
function addDays(date, days) {
    const result = new Date(date);
    result.setDate(result.getDate() + days);
    return result;
}

function subtractDays(date, days) {
    return addDays(date, -days);
}

const today = new Date();
console.log('Today:', today);
console.log('Tomorrow:', addDays(today, 1));
console.log('Yesterday:', subtractDays(today, 1));

// Method 2: Add/subtract months
function addMonths(date, months) {
    const result = new Date(date);
    result.setMonth(result.getMonth() + months);
    return result;
}

console.log('Next month:', addMonths(today, 1));
console.log('Last month:', addMonths(today, -1));

// Method 3: Add/subtract years
function addYears(date, years) {
    const result = new Date(date);
    result.setFullYear(result.getFullYear() + years);
    return result;
}

console.log('Next year:', addYears(today, 1));

// Method 4: Add/subtract hours
function addHours(date, hours) {
    const result = new Date(date);
    result.setHours(result.getHours() + hours);
    return result;
}

console.log('In 2 hours:', addHours(today, 2));

// Method 5: Add/subtract minutes
function addMinutes(date, minutes) {
    const result = new Date(date);
    result.setMinutes(result.getMinutes() + minutes);
    return result;
}

console.log('In 30 minutes:', addMinutes(today, 30));

// Method 6: Using timestamps
function addTime(date, milliseconds) {
    return new Date(date.getTime() + milliseconds);
}

console.log('Add 1 day (ms):', addTime(today, 24 * 60 * 60 * 1000));
console.log('Add 1 hour (ms):', addTime(today, 60 * 60 * 1000));

// Method 7: Date difference
function dateDifference(date1, date2) {
    const diff = Math.abs(date1 - date2);
    const days = Math.floor(diff / (1000 * 60 * 60 * 24));
    const hours = Math.floor((diff % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
    const minutes = Math.floor((diff % (1000 * 60 * 60)) / (1000 * 60));
    return { days, hours, minutes };
}

const date1 = new Date('2024-01-01');
const date2 = new Date('2024-01-15');
console.log('Difference:', dateDifference(date1, date2));