func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
    return Pockyt.shared.handleOpenURL(url)
}
  
@available(iOS 9.0, *)
func application(_ application: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
    return Pockyt.shared.handleOpenURL(url)
}

// For WeChat Pay
func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
    return Pockyt.shared.handleOpenUniversalLink(userActivity)
}

// For Alipay
let payment = Alipay(payInfo: payInfo, fromScheme: "pockyt2alipay")
Pockyt.shared.requestPay(payment) { result in
    DispatchQueue.main.async {
        self.resultLabel.text = "Paid: \(result.isSuccessful), cancelled: \(result.isCancelled), \(result)"
    }
}

// For WeChat Pay
let request = WechatPayRequest(partnerId: partnerid, prepayId: prepayid, packageValue: package, nonceStr: noncestr, timeStamp: timestamp, sign: sign)
Pockyt.shared.requestPay(WechatPay(request)) { result in
    DispatchQueue.main.async {
        self.resultLabel.text = "Paid: \(result.isSuccessful), cancelled: \(result.isCancelled), \(result)"
    }
}

// For Drop-in UI
let dropReq = BTDropInRequest()
// BTDropInRequest has many configuration options
// ThreeDSeucre for card, optional
// dropReq.threeDSecureRequest = createThreeDSecure()
let payment = DropInPay(uiViewController: self, clientToken: authorization, dropInRequest: dropReq)
Pockyt.shared.requestPay(payment) { result in
    DispatchQueue.main.async {
        if let nonce = result.dropInResult?.paymentMethod?.nonce{
            self.resultLabel.text = "Obtained nonce: \(result.isSuccessful), cancelled: \(result.isCancelled), nonce: \(nonce)"
        } else if .applePay == result.dropInResult?.paymentMethodType {
            self.resultLabel.text = result.respMsg
            // Note that Apple Pay requires continuing the payment flow initiation
            self.startApplePay()
        } else if let error = result.respMsg {
            self.resultLabel.text = "Failed to obtain nonce, cancelled: \(result.isCancelled), error: \(error)"
        } else {
            self.resultLabel.text = "Failed to obtain nonce, cancelled: \(result.isCancelled)"
        }
    }
}

// For PayPal
let request = BTPayPalCheckoutRequest(amount: "1.00")
let request = BTPayPalVaultRequest()
let paypal = PayPal(authorization: HttpUtils.CLIENT_TOKEN, paypalRequest: request)
Pockyt.shared.requestPay(paypal) { result in
    DispatchQueue.main.async {
        if result.isSuccessful {
            if let nonce = result.paypalAccountNonce?.nonce {
                self.resultLabel.text = "Obtained nonce: \(nonce)"
            } else {
                self.resultLabel.text = "Failed to obtain nonce"
            }
        } else {
            self.resultLabel.text = "Failed to obtain nonce, error: \(result.respMsg ?? "Unknown error")"
        }
    }
}

// For Venmo
let request = BTVenmoRequest()
request.paymentMethodUsage = .multiUse
let venmo = Venmo(authorization: HttpUtils.CLIENT_TOKEN, venmoRequest: request)
Pockyt.shared.requestPay(venmo) { result in
    DispatchQueue.main.async {
        if result.isSuccessful {
            if let nonce = result.venmoNonce?.nonce {
                self.resultLabel.text = "Obtained nonce: \(nonce)"
            } else {
                self.resultLabel.text = "Failed to obtain nonce"
            }
        } else {
            self.resultLabel.text = "Failed to obtain nonce, error: \(result.respMsg ?? "Unknown error")"
        }
    }
}

// For Apple Pay, There are a few additional steps in the payment process compared to the ones mentioned above
// First, initialize the Apple Pay request parameters
let applePay = ApplePay(viewController: self, authorization: HttpUtils.CLIENT_TOKEN)
applePay.initPaymentRequest() { paymentRequest, error in
    DispatchQueue.main.async {
        if let paymentRequest = paymentRequest {
            self.resultLabel.text = "Payment request initialized"
            self.showApplePaySheet(paymentRequest: paymentRequest)
            self.presentAuthorizationViewController(applePay)
        } else {
            self.resultLabel.text = "Failed to initialize payment request"
        }
    }
}
// Then, present the Apple Pay sheet
private func showApplePaySheet(paymentRequest: PKPaymentRequest) {
    paymentRequest.requiredBillingContactFields = [.postalAddress]
    // Set other PKPaymentRequest properties here
    paymentRequest.merchantCapabilities = .capability3DS
    paymentRequest.paymentSummaryItems =
    [
        PKPaymentSummaryItem(label: "test_item", amount: NSDecimalNumber(string: "0.02")),
        // Add add'l payment summary items...
        PKPaymentSummaryItem(label: "Pockyt.io", amount: NSDecimalNumber(string: "0.02")),
    ]
    // ...
}
// Secondly, present the Apple Pay authorization view controller
private func presentAuthorizationViewController(_ applePay: ApplePay) {
    applePay.requestPay() { result in
        DispatchQueue.main.async {
            if result.isSuccessful {
                self.resultLabel.text = "Payment processing, please wait..."
                self.submitNonceToServer(applePay: applePay, transactionNo: "xxx", nonce: result.applePayNonce!.nonce)
                self.resultLabel.text = "Payment successful, nonce: \(result.applePayNonce!.nonce)"
            } else {
                self.resultLabel.text = result.respMsg
            }
        }
    }
}
// Finally, Submit the Apple Pay nonce to your server, Notify the Apple Pay wallet of the payment status based on the API result
if (apiSuccess) {
    applePay.notifyPaymentCompletion(true)
} else {
    applePay.notifyPaymentCompletion(false)
}