ts-time-utils/dist/age.js

A comprehensive TypeScript utility library for time, dates, durations, and calendar operations with full tree-shaking support

/**
 * Calculate detailed age from birth date
 * @param birthDate - date of birth
 * @param referenceDate - date to calculate age from (defaults to now)
 */
export function calculateAge(birthDate, referenceDate = new Date()) {
    const birth = new Date(birthDate);
    const reference = new Date(referenceDate);
    let years = reference.getFullYear() - birth.getFullYear();
    let months = reference.getMonth() - birth.getMonth();
    let days = reference.getDate() - birth.getDate();
    // Adjust for negative days
    if (days < 0) {
        months--;
        const lastMonth = new Date(reference.getFullYear(), reference.getMonth(), 0);
        days += lastMonth.getDate();
    }
    // Adjust for negative months
    if (months < 0) {
        years--;
        months += 12;
    }
    const totalDays = Math.floor((reference.getTime() - birth.getTime()) / (1000 * 60 * 60 * 24));
    const totalMonths = years * 12 + months;
    return { years, months, days, totalDays, totalMonths };
}
/**
 * Get age in specific units
 * @param birthDate - date of birth
 * @param unit - unit to return age in
 * @param referenceDate - date to calculate from (defaults to now)
 */
export function getAgeInUnits(birthDate, unit, referenceDate = new Date()) {
    const diffMs = referenceDate.getTime() - birthDate.getTime();
    switch (unit) {
        case 'years':
            return Math.floor(diffMs / (1000 * 60 * 60 * 24 * 365.25));
        case 'months':
            return Math.floor(diffMs / (1000 * 60 * 60 * 24 * 30.44));
        case 'weeks':
            return Math.floor(diffMs / (1000 * 60 * 60 * 24 * 7));
        case 'days':
            return Math.floor(diffMs / (1000 * 60 * 60 * 24));
        case 'hours':
            return Math.floor(diffMs / (1000 * 60 * 60));
        case 'minutes':
            return Math.floor(diffMs / (1000 * 60));
        case 'seconds':
            return Math.floor(diffMs / 1000);
        case 'milliseconds':
        default:
            return diffMs;
    }
}
/**
 * Determine life stage based on age
 * @param birthDate - date of birth
 * @param referenceDate - date to calculate from (defaults to now)
 */
export function getLifeStage(birthDate, referenceDate = new Date()) {
    const ageInYears = getAgeInUnits(birthDate, 'years', referenceDate);
    if (ageInYears < 2)
        return 'infant';
    if (ageInYears < 13)
        return 'child';
    if (ageInYears < 18)
        return 'teen';
    if (ageInYears < 65)
        return 'adult';
    return 'senior';
}
/**
 * Get the next birthday date
 * @param birthDate - date of birth
 * @param referenceDate - date to calculate from (defaults to now)
 */
export function getNextBirthday(birthDate, referenceDate = new Date()) {
    const birth = new Date(birthDate);
    const reference = new Date(referenceDate);
    const nextBirthday = new Date(reference.getFullYear(), birth.getMonth(), birth.getDate());
    // If birthday has passed this year, get next year's birthday
    if (nextBirthday <= reference) {
        nextBirthday.setFullYear(reference.getFullYear() + 1);
    }
    return nextBirthday;
}
/**
 * Get days until next birthday
 * @param birthDate - date of birth
 * @param referenceDate - date to calculate from (defaults to now)
 */
export function getDaysUntilBirthday(birthDate, referenceDate = new Date()) {
    const nextBirthday = getNextBirthday(birthDate, referenceDate);
    return Math.ceil((nextBirthday.getTime() - referenceDate.getTime()) / (1000 * 60 * 60 * 24));
}
/**
 * Check if today is someone's birthday
 * @param birthDate - date of birth
 * @param referenceDate - date to check (defaults to now)
 */
export function isBirthday(birthDate, referenceDate = new Date()) {
    const birth = new Date(birthDate);
    const reference = new Date(referenceDate);
    return (birth.getMonth() === reference.getMonth() &&
        birth.getDate() === reference.getDate());
}