Returns holidays for a year, country and state. Many countries are supported

holidays.ts

import dateHolidays from 'https://cdn.skypack.dev/date-holidays';
import { ld } from 'https://x.nest.land/[email protected]/mod.ts'
import { parse } from "https://deno.land/std/flags/mod.ts"

/**
 * returns a command line argument by name from the args array
 */
const getArg = function(argName: string, args: any[]): string {
	//@ts-ignore
	const arg = ld.find(args, (arg: string[]) => arg[0] === argName)
	return arg ? arg[1]: null
}

/**
 * Helper method that logs a msg if debug flag is set
 */
const logDebug=function(msg: any) {
  if(bDebug) {
    console.log(msg)
  }
}
// parse the args array into an array of 2-dimensionals array.
// Each array element is an array with 2 members: 0-argument, 1-argument value
const args = ld.toPairs(parse(Deno.args))
//console.log(args)
// save the command line parameters in variables.
const bHelp = getArg('help', args)
const bDebug = getArg('debug', args)
const year = getArg('year', args) || getArg('_', args)[0] || new Date().getFullYear()
const country = getArg('country', args) || getArg('_', args)[1] || "DE"
const state = getArg('state', args) || getArg('_', args)[2] || "NI"
const bCountries = getArg('countries', args)
const bStates = getArg('states', args)
const bQuery = getArg('query', args)

logDebug(args)
logDebug(year)

class HolidayViewer {
  private hd: dateHolidays

  constructor() {
    this.hd = new dateHolidays(country, state, null, null);
  }


  processInput() {
    if(bCountries) {
      this.showCountries()
    } else if(bStates) {
      this.showStates()
    } else if(bQuery) {
      this.showQueryResults()
    } else {
      this.showHolidays()
    }
  }

  showQueryResults() {
    let queryResult = this.hd.query(country)
    console.log(queryResult)
  }

  showCountries() {
    let countries = this.hd.getCountries()
    console.log(countries)
  }

  showStates() {
    let states = this.hd.getStates(country)
    console.log(states);
  }

  showHolidays() {
    let holidays:Array<any> = this.hd.getHolidays(year, "de");

    let publics:Array<{date:string, name:string}> = holidays.filter(holiday => {return holiday.type === "public"})
                  .map(entry => {return {date: entry.date, name: entry.name}});
    console.log(JSON.stringify(publics));
    // Deno.stdout.writeSync(new TextEncoder().encode(JSON.stringify(publics)));
  }

}

if(bHelp) {
  console.log('Usage: holidays <year country state> [options]') 
  console.log('Usage: hoidays [options]') 
  console.log(`
Returns the holidays for a year, country and state.
ex: holidays 2022 DE NI -> this returns the holidays for lower saxony in germany

Options
--year:      year for which to show the holidays
--country:   country for which you want to see the date-holidays. Get a list of countries with holidays --countries
--countries: get a list of supported countries
--states:    get a list of available states for a country. Needs --country to be set. Get a list of states with e.g. holidays --states --country DE
--state:     state of the country for which you want to see the holidays
--help:      show this help screen
--debug:     show debug information
`)
  Deno.exit(0);
}

new HolidayViewer().processInput();