Manejo de fechas con vanilla JS

date-formate.js

//Fecha actual
const date = new Date()

//Fecha menos X dias - ejm 1
const day_past = new Date(new Date().getTime() - 1*86400000)

//Formato de fechas: 
const day = '0'.concat(date.getDate()).slice(-2) // dd
const month = '0'.concat(date.getMonth() + 1).slice(-2) // mm
const year = date.getFullYear() // yyyy

const hours = '0'.concat(date.getHours()).slice(-2)
const minutes = '0'.concat(date.getMinutes()).slice(-2)

const hours12 = '0'.concat(hours % 12 || 12).slice(-2)
const period = hours < 12 ? 'AM' : 'PM'

// return `${hours}:${minutes} ${day}/${month}/${year}`
// return `${day}/${month}/${year} (${hours12}:${minutes} ${period})`