Calculates weekdays, sundays, saturdays and total days for a time period

days.ts

/* run with 'deno days --help' 
 */
import containedPeriodicValues from 'https://cdn.skypack.dev/contained-periodic-values';
import sugarDate from 'https://cdn.skypack.dev/sugar-date';
import { ld } from 'https://x.nest.land/deno-lodash@1.0.0/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 start = getArg('start', args) || getArg('_', args)[0] || "last month"
const end = getArg('end', args) || getArg('_', args)[1] || "today"

logDebug(args)


class Days {
  calc(start:any, end:any) {
    // console.log(start.raw)
    // console.log(end.raw)
    let startDay = start.raw.getDay()
    let days = sugarDate.Date.range(start.raw, end.raw).days()
    let sundays = containedPeriodicValues(startDay, days + startDay, 0, 7)
    let saturdays = containedPeriodicValues(startDay, days + startDay, 6, 7)
    let daysResult = {start: sugarDate.Date.short(start), end: sugarDate.Date.short(end), total: days, sundays: sundays, saturdays: saturdays, weekdays: days-sundays-saturdays}
    return daysResult
  }
}

if(bHelp) {
  console.log('Usage: days <start end> [options]') 
  console.log(`
Options
--start:     start date. Can be any of sugarjs.com constructor values
--end:       end date. Can be any of sugarjs.com constructor values
--help:      show this help screen
--debug:     show debug information
`)
  Deno.exit(0);
}

let daysResult = new Days().calc(sugarDate.Date(start).reset(), sugarDate.Date(end))
console.log(JSON.stringify(daysResult))