detect 12 or 24 hour.swift

func usesAMPM() -> Bool {
    let locale = NSLocale.currentLocale()
    let dateFormat = NSDateFormatter.dateFormatFromTemplate("j", options: 0, locale: locale)!
    if dateFormat.rangeOfString("a") != nil {
        return true
    }
    else {
        return false
    }
}

func hourInLocalFormat(hour:Int) -> String {
    let currentTimeFormatter = NSDateFormatter()
    currentTimeFormatter.dateFormat = "HH"
    let date2 = currentTimeFormatter.dateFromString("\(hour)")
    let formatter = NSDateFormatter()
    if usesAMPM(){
        formatter.dateFormat = "h aa"
    } else {
        formatter.dateFormat = "H"
    }
    return formatter.stringFromDate(date2!)
}