Check Credit Card Valid

//newway :

//http://stackoverflow.com/questions/33137885/validating-credit-cards-using-stripe-with-ios



extension ViewController: UITextFieldDelegate {
    internal func textFieldDidEndEditing(_ textField: UITextField) {
        //let (type, formatted, valid) = checkCardNumber(stringWithCardNumber)
        print(checkCardNumber(input: textField.text!))
    }

}

enum CardType: String {
    case Unknown, Amex, Visa, MasterCard, Diners, Discover, JCB, Elo, Hipercard, UnionPay

    static let allCards = [Amex, Visa, MasterCard, Diners, Discover, JCB, Elo, Hipercard, UnionPay]
    static let imgCards = ["stp_card_amex", "stp_card_visa", "stp_card_mastercard", "stp_card_diners", "stp_card_discover", "stp_card_jcb", "stp_card_visa", "stp_card_visa", "stp_card_visa"]

    var regex : String {
        switch self {
        case .Amex:
            return "^3[47][0-9]{5,}$"
        case .Visa:
            return "^4[0-9]{6,}([0-9]{3})?$"
        case .MasterCard:
            return "^(5[1-5][0-9]{4}|677189)[0-9]{5,}$"
        case .Diners:
            return "^3(?:0[0-5]|[68][0-9])[0-9]{4,}$"
        case .Discover:
            return "^6(?:011|5[0-9]{2})[0-9]{3,}$"
        case .JCB:
            return "^(?:2131|1800|35[0-9]{3})[0-9]{3,}$"
        case .UnionPay:
            return "^(62|88)[0-9]{5,}$"
        case .Hipercard:
            return "^(606282|3841)[0-9]{5,}$"
        case .Elo:
            return "^((((636368)|(438935)|(504175)|(451416)|(636297))[0-9]{0,10})|((5067)|(4576)|(4011))[0-9]{0,12})$"
        default:
            return ""
        }
    }
}

func matchesRegex(regex: String!, text: String!) -> Bool {
        do {
            let regex = try NSRegularExpression(pattern: regex, options: [.caseInsensitive])
            let nsString = text as NSString
            let match = regex.firstMatch(in: text, options: [], range: NSMakeRange(0, nsString.length))
            return (match != nil)
        } catch {
            return false
        }
    }
    func luhnCheck(number: String) -> Bool {
        var sum = 0
        let digitStrings = number.characters.reversed().map { String($0) }

        for tuple in digitStrings.enumerated() {
            guard let digit = Int(tuple.element) else { return false }
            let odd = Int(tuple.element)! % 2 == 1

            switch (odd, digit) {
            case (true, 9):
                sum += 9
            case (true, 0...8):
                sum += (digit * 2) % 9
            default:
                sum += digit
            }
        }

        return sum % 10 == 0
    }

    func checkCardNumber(input: String) -> (type: CardType, formatted: String, valid: Bool) {
        // Get only numbers from the input string
        //let numberOnly = input.stringByReplacingOccurrencesOfString("[^0-9]", withString: "", options: .RegularExpressionSearch)
        let numberOnly = input.replacingOccurrences(of: "[^0-9]", with: "", options: .regularExpression)
        var type: CardType = .Unknown
        var formatted = ""
        var valid = false

        // detect card type
        for card in CardType.allCards {
            if (matchesRegex(regex: card.regex, text: numberOnly)) {
                type = card
                break
            }
        }

        // check validity
        valid = luhnCheck(number: numberOnly)

        // format
        var formatted4 = ""
        for character in numberOnly.characters {
            if formatted4.characters.count == 4 {
                formatted += formatted4 + " "
                formatted4 = ""
            }
            formatted4.append(character)
        }

        formatted += formatted4 // the rest

        // return the tuple
        return (type, formatted, valid)
    }