randulate/src/datetime.js

Randulate is an npm package that simplifies the process of generating fake data for development, testing, and various other use cases. It allows you to create randomized data based on provided specifications and data types.

const {
  calculateAgeInMilliseconds,
  getTimeUnits
} = require('./helper');


/**
 * Generates a random date within a specified range.
 *
 * e.g:
 * const startDate = new Date('2023-01-01');
 * const endDate = new Date('2023-12-31');
 * const randomDate = getRandomDate(startDate, endDate);
 *
 * @param {Date} startDate - The start date of the range.
 * @param {Date} endDate - The end date of the range.
 * @returns {Date} A randomly generated date within the specified range.
 */
const getRandomDate = (startDate, endDate) => {
  const startTimestamp = startDate.getTime();
  const endTimestamp = endDate.getTime();
  const randomTimestamp = startTimestamp + Math.random() * (endTimestamp - startTimestamp);

  return new Date(randomTimestamp);
}


/**
 * Generates a random time in 24-hour format.
 *
 * @returns {string} A string representing a random time in the format 'hh:mm:ss'.
 */
const getRandomTime = () => {
  const hours = Math.floor(Math.random() * 24);
  const minutes = Math.floor(Math.random() * 60);
  const seconds = Math.floor(Math.random() * 60);

  return `${hours}:${minutes}:${seconds}`;
}


/**
 * Calculates the difference between two dates and returns a human-readable string representation in terms of years, months, days, hours, minutes, and seconds.
 *
 * e.g:
 * const startDate = new Date('2023-01-01');
 * const endDate = new Date('2023-12-31');
 * const dateDifference = Randulate.dateDifference(startDate, endDate);
 *
 * @param {Date} date1 - The first date.
 * @param {Date} date2 - The second date.
 * @returns {string} A human-readable string representing the time difference between the two dates.
 */
const dateDifference = (date1, date2) => {
  let difference = Math.abs(date1 - date2);
  const units = getTimeUnits();

  return units.reduce((output, unit) => {
    const value = Math.floor(difference / unit.ms);
    difference -= value * unit.ms;

    return value > 0 ? output + value + ' ' + unit.label + (value > 1 ? 's ' : ' ') : output;
  },
  ''
  ).trim();
}


/**
 * Calculates and returns a human-readable countdown timer string representing the time remaining between the current date and a specified future date.
 *
 * @param {Date} futureDate - The future date and time to count down to.
 * @returns {string} A string representing the time remaining in days, hours, minutes, and seconds.
 *
 * @example
 * // Example usage:
 * // Set a future date (e.g., December 31, 2023, 23:59:59)
 * const futureDate = new Date('2023-12-31T23:59:59');
 * countdownTimer(futureDate);
 */
const countdownTimer = (futureDate) => {
  const currentDate = new Date();
  const differenceInMilliseconds = futureDate.getTime() - currentDate.getTime();
  const millisecondsInDay = 1000 * 60 * 60 * 24;
  const millisecondsInHour = 1000 * 60 * 60;
  const millisecondsInMinute = 1000 * 60;

  // Calculate the remaining time in days, hours, minutes, and seconds
  const days = Math.floor(differenceInMilliseconds / millisecondsInDay);
  const hours = Math.floor((differenceInMilliseconds % (millisecondsInDay)) / millisecondsInHour);
  const minutes = Math.floor((differenceInMilliseconds % millisecondsInHour) / millisecondsInMinute);
  const seconds = Math.floor((differenceInMilliseconds % millisecondsInMinute) / 1000);

  return `Time Remaining: ${days} days, ${hours} hours, ${minutes} minutes, ${seconds} seconds`;
}


/**
 * Calculates and returns various details about the age based on the provided date of birth.
 *
 * @param {string} dateOfBirth - The date of birth in either "YYYY-MM-DD" or "MM-DD-YYYY" format.
 *
 * @throws {Error} Throws an error if the provided date of birth is invalid or in an unsupported format.
 *
 * @returns {Object} An object containing details about the age, including minutes, seconds, and milliseconds.
 *
 * @example
 * // Pass a date of birth in either "YYYY-MM-DD" or "MM-DD-YYYY" format
 * const customDateOfBirth1 = "1990-01-12";
 * const customDateOfBirth2 = "01-12-1990";
 * getAgeDetails(customDateOfBirth1); // Example with "YYYY-MM-DD" format
 * getAgeDetails(customDateOfBirth2); // Example with "MM-DD-YYYY" format
 */
const getAgeDetails = (dateOfBirth) => {
  if (dateOfBirth) {
    const ageInMilliseconds = calculateAgeInMilliseconds(dateOfBirth);
    const ageInSeconds = ageInMilliseconds / 1000;
    const ageInMinutes = ageInSeconds / 60;

    return {
      minutes: ageInMinutes.toFixed(4),
      seconds: ageInSeconds.toFixed(4),
      milliseconds: ageInMilliseconds
    };
  } else {
    throw new Error('Invalid date of birth. Please try again.');
  }
}


module.exports = {
  countdownTimer,
  dateDifference,
  getAgeDetails,
  getRandomDate,
  getRandomTime
};