module.exports = function gmmktime() {
  //  discuss at: https://locutus.io/php/gmmktime/
  // original by: Brett Zamir (https://brett-zamir.me)
  // original by: mktime
  //   example 1: gmmktime(14, 10, 2, 2, 1, 2008)
  //   returns 1: 1201875002
  //   example 2: gmmktime(0, 0, -1, 1, 1, 1970)
  //   returns 2: -1

  const d = new Date()
  const r = arguments
  let i = 0
  const e = ['Hours', 'Minutes', 'Seconds', 'Month', 'Date', 'FullYear']

  for (i = 0; i < e.length; i++) {
    if (typeof r[i] === 'undefined') {
      r[i] = d['getUTC' + e[i]]()
      // +1 to fix JS months.
      r[i] += i === 3
    } else {
      r[i] = parseInt(r[i], 10)
      if (isNaN(r[i])) {
        return false
      }
    }
  }

  // Map years 0-69 to 2000-2069 and years 70-100 to 1970-2000.
  r[5] += r[5] >= 0 ? (r[5] <= 69 ? 2e3 : r[5] <= 100 ? 1900 : 0) : 0

  // Set year, month (-1 to fix JS months), and date.
  // !This must come before the call to setHours!
  d.setUTCFullYear(r[5], r[3] - 1, r[4])

  // Set hours, minutes, and seconds.
  d.setUTCHours(r[0], r[1], r[2])

  const time = d.getTime()

  // Divide milliseconds by 1000 to return seconds and drop decimal.
  // Add 1 second if negative or it'll be off from PHP by 1 second.
  return ((time / 1e3) >> 0) - (time < 0)
}