Format time by hour of the day and minute of the hour

formatTime.js

/**
 * Returns formatted time depending on the clock (e.g. 00:00 / 12:00am)
 * @param {number} hour - The hour of the day (0-24)
 * @param {number} minute - The minute of the the hour (0-59)
 * @param {string} clock - Either "12h" or "24h"
 * @returns The time as a well formated string or false in case of an error
 */
function formatTime(hour, minute, clock) {
	( minute < 10 )
		? minute = '0' + minute
		: minute = '' + minute

	if ( clock === '12h' ) {
		// Attach a.m / p.m.
		if ( hour < 12 || hour === 24 )
			minute += 'am'
		else
			minute += 'pm'

		// 12h clock specific transformations 00:00/24:00 -> 12 am, 12:00 -> 12:00pm
		if ( hour === 0 )
			hour = 12
		else if ( hour === 24 )
			hour = 0
		// Decrease hour by 12 on noon
		else if ( hour > 13 )
			hour -= 12
	}

	hour = '' + hour

	if (hour.length === 1)
		hour = '0' + hour

	return hour + ':' + minute
}