using CoreScanner;
using SafeBagDE70.API;
using Serilog;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Automation;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Xml;
using System.Xml.Linq;

namespace SafeBagDE70
{
    /// <summary>
    /// Interaction logic for WelcomeWindow.xaml
    /// </summary>
    public partial class WelcomeUC : UserControl
    {
        public string? PinCode = null;
        public bool IsAuthenticated = false;
        public CCoreScannerClass? cCoreScannerClass=null;
        public WelcomeUC()
        {
            InitializeComponent();
            InitQRCodeScanner();
            Loaded += WelcomeUC_Loaded;
        }

        private void WelcomeUC_Loaded(object sender, RoutedEventArgs e)
        {
            AppData.IsAuthenticated = false;
            txtVersion.Text = "Version " + AppData.CurrentVersion;
        }
        public void Init()
        {
            AppData.IsAuthenticated = false;
            AppData.CurrentCustomerAccount = null;
            lblPincodeError.Content = "";
            PinCodeBox.Text = "";
            QrCodePanel.Visibility = Visibility.Collapsed;
        }
        public void ShowLogin()
        {
            gridInfor.Visibility = Visibility.Collapsed;
            gridMain.Visibility = Visibility.Visible;
        }
        public void ShowInfor(string strMessage)
        {
            gridInfor.Visibility = Visibility.Visible;
            gridMain.Visibility = Visibility.Collapsed;
            txtInfor.Text = strMessage;
            txtInfor.Foreground = new SolidColorBrush(Colors.DarkRed);
        }
        private void LoginButton_Click(object sender, RoutedEventArgs e)
        {

            string pin = PinCodeBox.Text;

            if (ValidatePin(pin))
            {
                PinCode=PinCodeBox.Text.ToString();
                if (AppData.customerAccounts != null)
                {
                    CustomerAccount? cca = null;
                    if (PinCode != null)
                    {
                        var strPincode = PinCode.ToUpper();
                        cca = AppData.customerAccounts.Where(x => x.PINCode == strPincode).FirstOrDefault();
                    }

                    if (cca != null)
                    {
                        AppData.IsAuthenticated=true;
                        AppData.CurrentCustomerAccount=cca;
                        AppData.CreateNewTransactionCode();
                        ((MainWindow)Application.Current.MainWindow).ShowDepositScreen();
                        //DialogResult = true;
                        //this.Close();
                    }
                    else
                    {
                        lblPincodeError.Content = "PINCODE không đúng, vui lòng thử lại";
                    }
                }
            }
            else
            {
                MessageBox.Show("Invalid PIN. Please try again.");
            }
        }

        private void ForgotPin_Click(object sender, RoutedEventArgs e)
        {
            MessageBox.Show("Forgot PIN clicked.");
        }

        private void Help_Click(object sender, RoutedEventArgs e)
        {
            MessageBox.Show("Phiên bản đang sử dụng là phiên bản mới nhất");
        }

        private bool ValidatePin(string pin)
        {
            return true;

        }
        private async void PinCodeButton_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                QrCodePanel.Visibility = Visibility.Collapsed;
                PinCodePanel.Visibility = Visibility.Visible;

                cCoreScannerClass.BarcodeEvent -= new _ICoreScannerEvents_BarcodeEventEventHandler(OnBarcodeEvent);
            }
            catch { 

            }
     
        }
        private void btnQRCodeLogin_Click(object sender, RoutedEventArgs e)
        {
            PinCodePanel.Visibility = Visibility.Collapsed;
            QrCodePanel.Visibility=Visibility.Visible;
            cCoreScannerClass.BarcodeEvent += new _ICoreScannerEvents_BarcodeEventEventHandler(OnBarcodeEvent);


        }
        public void InitQRCodeScanner()
        {
            try
            {
                // Instantiate CoreScanner Class
                cCoreScannerClass = new CCoreScannerClass();

                // Call Open API
                short[] scannerTypes = new short[1];    // Scanner Types you are interested in
                scannerTypes[0] = 1;                    // 1 for all scanner types
                short numberOfScannerTypes = 1;         // Size of the scannerTypes array 
                int status;                             // Extended API return code

                cCoreScannerClass.Open(0, scannerTypes, numberOfScannerTypes, out status);
                short numberOfScanners;                         // Number of scanners expect to be used 
                int[] connectedScannerIDList = new int[255];    // List of scanner IDs to be returned 
                string outXML;
                cCoreScannerClass.GetScanners(out numberOfScanners, connectedScannerIDList, out outXML, out status);
                if (numberOfScanners > 0)
                {
                    // Let's subscribe for events
                    int opcode = 1001;  // Method for Subscribe events 
                                        //string outXML;      // XML Output
                    string inXML = "<inArgs>" +
                                        "<cmdArgs>" +
                                            "<arg-int>1</arg-int>" + // Number of events you want to subscribe
                                            "<arg-int>1</arg-int>" + // Comma separated event IDs
                                        "</cmdArgs>" +
                    "</inArgs>";

                    cCoreScannerClass.ExecCommand(opcode, ref inXML, out outXML, out status);
                }
                else
                {
                    Log.Information("Không tìm thấy đầu đọc QR");
                    AppData.DeviceStatus.OtherError = 1;
                    AppData.DeviceStatus.Description = "Không tìm thấy đầu đọc QR";
                    APIModels.SendEvent(AppData.DeviceStatus);
                }    
            }
            catch (Exception exp)
            {
                Console.WriteLine("Something wrong please check... " + exp.Message);
            }
        }
        private void OnBarcodeEvent(short eventType, ref string pscanData)
        {
            string xmlString = pscanData;
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.LoadXml(xmlString);

            XmlNode rawDataNode = xmlDoc.SelectSingleNode("//datalabel");
            string rawDataHex = rawDataNode.InnerText.Trim();

            var QRCodeContentFull = HexStringToString(rawDataHex);
            string? CustomerID = null;
            VerifyQRCode(QRCodeContentFull, out CustomerID);
            if(CustomerID!=null)
            {
                this.Dispatcher.Invoke(() =>
                {
                    if (AppData.customerAccounts != null)
                    {
                        CustomerAccount? cca = null;
                        if (CustomerID != null)
                        {
                            cca = AppData.customerAccounts.Where(x => x.QRCode == CustomerID).FirstOrDefault();
                        }

                        if (cca != null)
                        {
                            cCoreScannerClass.BarcodeEvent -= new _ICoreScannerEvents_BarcodeEventEventHandler(OnBarcodeEvent);
                            AppData.IsAuthenticated = true;
                            AppData.CurrentCustomerAccount = cca;
                            AppData.CreateNewTransactionCode();
                            ((MainWindow)Application.Current.MainWindow).ShowDepositScreen();
                        }
                        else
                        {
                            lblQRcodeError.Content = "QRCODE không đúng, vui lòng thử lại";
                        }
                    }

                });
            }    
           
        }
        private void VerifyQRCode(string decodedString,out string? ConsumerID)
        {
            ConsumerID = null;
            try
            {
                var qrCodeData = decodedString;
                // Extract the CRC from the QR code string
                string extractedCRC = qrCodeData.Substring(qrCodeData.Length - 4);
                // Get the data without the CRC part
                string dataWithoutCRC = qrCodeData.Substring(0, qrCodeData.Length - 8);

                // Calculate CRC
                string calculatedCRC = CalculateCRC(dataWithoutCRC);

                // Verify CRC
                if (extractedCRC.Equals(calculatedCRC, StringComparison.OrdinalIgnoreCase))
                {
                    this.Dispatcher.Invoke(() =>
                    {
                        lblQRcodeError.Content = "CRC is valid.";
                    });

                    Dictionary<string, (int Length, string Value)> fields = ExtractFields(qrCodeData);

                    foreach (var field in fields)
                    {
                        Console.WriteLine($"ID: {field.Key}, Length: {field.Value.Length}, Value: {field.Value.Value}");
                    }
                    var fields2 = ExtractFields(fields["38"].Value);
                    var fields3 = ExtractFields(fields2["01"].Value);
                    ConsumerID = fields3["01"].Value;
                }
                else
                {
                    this.Dispatcher.Invoke(() =>
                    {
                        lblQRcodeError.Content = "CRC is invalid.";
                    });
                   
                }

               
            }
            catch (Exception e)
            {
                this.Dispatcher.Invoke(() =>
                {
                    lblQRcodeError.Content = e.Message;
                });
               
            }
        }
         Dictionary<string, (int Length, string Value)> ExtractFields(string qrCodeData)
        {
            Dictionary<string, (int Length, string Value)> fields = new Dictionary<string, (int Length, string Value)>();

            int currentIndex = 0;

            while (currentIndex < qrCodeData.Length)
            {
                // Extract ID
                string id = qrCodeData.Substring(currentIndex, 2);
                currentIndex += 2;

                // Extract Length
                int length = int.Parse(qrCodeData.Substring(currentIndex, 2));
                currentIndex += 2;

                // Extract Value
                string value = qrCodeData.Substring(currentIndex, length);
                currentIndex += length;

                // Add the field to the dictionary
                fields[id] = (length, value);
            }

            return fields;
        }
        string CalculateCRC(string data)
        {
            ushort polynomial = 0x1021;  // CRC-16-CCITT polynomial
            ushort crc = 0xFFFF;         // Initial value

            // Convert the string to a byte array
            byte[] bytes = Encoding.ASCII.GetBytes(data + "6304"); // Append "6304" for CRC calculation as per standard

            foreach (byte b in bytes)
            {
                crc ^= (ushort)(b << 8);

                for (int i = 0; i < 8; i++)
                {
                    if ((crc & 0x8000) != 0)
                    {
                        crc = (ushort)((crc << 1) ^ polynomial);
                    }
                    else
                    {
                        crc <<= 1;
                    }
                }
            }

            // Ensure CRC is a 16-bit value
            crc &= 0xFFFF;

            // Return CRC as a hexadecimal string
            return crc.ToString("X4");
        }
        static string HexStringToString(string hexString)
        {
            string[] hexValues = hexString.Split(new[] { " " }, StringSplitOptions.RemoveEmptyEntries);
            byte[] bytes = new byte[hexValues.Length];

            for (int i = 0; i < hexValues.Length; i++)
            {
                bytes[i] = Convert.ToByte(hexValues[i], 16);
            }
            return Encoding.ASCII.GetString(bytes);
        }
    }
}