randulate/src/country.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 countries = require('../lib/consts/countries');
const { filterByProperty } = require('./helper');


/**
 * Retrieves information about a specific country based on its name.
 *
 * @param {string} countryName - The name of the country to retrieve information for.
 * @returns {Object|null} An object containing details about the specified country, or null if the country is not found.
 */
const getCountryInfo = (countryName) => {
  const lowercaseCountryName = countryName.toLowerCase();

  return countries[
    Object.keys(countries).find(key => key.toLowerCase() === lowercaseCountryName)
  ] || null;
}


/**
 * Retrieves and returns an array containing the names of all countries.
 *
 * @returns {Array} An array of country names.
 */
const listAllCountries = () => Object.keys(countries);


/**
 * Calculates and returns the total approximate population of all countries.
 *
 * @returns {number} The total approximate population of all countries.
 */
const getTotalPopulation = () =>
  Object.values(countries).reduce(
    (previousValue, { approximatePopulation }) => previousValue + approximatePopulation,
    0
  );


/**
 * Retrieves countries based on their driving side and returns an array of their names.
 *
 * @param {string} side - The driving side to filter countries by ('Right' or 'Left').
 * @returns {Array} An array of country names with the specified driving side.
 */
const getCountriesByDrivingSide = (side) =>
  filterByProperty('drivingSide', drivingSide => drivingSide.toLowerCase() === side.toLowerCase(), countries);


/**
 * Retrieves countries with an area in mi² larger than a specified threshold and returns an array of their names.
 *
 * @param {number} thresholdArea - The minimum area in mi² required for a country to be included.
 * @returns {Array} An array of country names with an area larger than the specified threshold.
 */
const getCountriesWithLargerAreaThan = (thresholdArea) =>
  filterByProperty('area', area => area > thresholdArea, countries);


/**
 * Finds countries with a specified capital (case-insensitive) and returns an array of their names.
 *
 * @param {string} targetCapital - The capital to search for among the countries.
 * @returns {Array} An array of country names with the specified capital (case-insensitive).
 */
const findCountriesByCapital = (targetCapital) =>
  Object.entries(countries)
    .filter(([, { capital }]) => capital && capital.toLowerCase() === targetCapital.toLowerCase())
    .map(([countryName]) => countryName);


/**
 * Sorts countries by population in descending order and returns an array of country names.
 *
 * @returns {Array} An array of country names sorted by population in descending order.
 */
const sortCountriesByPopulation = () =>
  Object.entries(countries)
    .sort(([, a], [, b]) => b.approximatePopulation - a.approximatePopulation)
    .map(([countryName]) => countryName);


/**
 * Retrieves the name of the largest country by area in mi² from a collection of countries.
 *
 * @returns {string|null} The name of the largest country by area or null if the collection is empty.
 */
const getLargestCountryByArea = () =>
  Object.entries(countries)
    .reduce((largestCountry, [countryName, { area }]) =>
      area > largestCountry.area ? { name: countryName, area } : largestCountry,
      { name: '', area: 0 }
    ).name || null;


module.exports = {
  findCountriesByCapital,
  getCountriesWithLargerAreaThan,
  getCountriesByDrivingSide,
  getCountryInfo,
  getLargestCountryByArea,
  getTotalPopulation,
  listAllCountries,
  sortCountriesByPopulation
};