using Parse;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.WindowsRuntime;
using System.Text;
using System.Threading.Tasks;
using Windows.ApplicationModel;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Networking.Sockets;
using Windows.Storage.Streams;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Windows.Web.Http;
using Windows.Web.Http.Filters;

// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234238

namespace TestProxy
{
    public struct INTERNET_PROXY_INFO
    {
        public uint dwAccessType;
        public string lpszProxy;
        public string lpszProxyBypass;
    }

    public partial class NativeMethods
    {
        [DllImport("urlmon.dll", CharSet = CharSet.Ansi)]
        public static extern uint UrlMkSetSessionOption(uint dwOption, [System.Runtime.InteropServices.InAttribute()] System.IntPtr lpBuffer, uint dwBufferLength, uint dwReserved);
    }

    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
        }

        public uint INTERNET_OPEN_TYPE_PROXY =                       3;   // via named proxy
        public uint INTERNET_OPTION_PROXY =                          38;

        private async void Button_Click(object sender, RoutedEventArgs e)
        {
            this.server = new StreamSocketListener();
            this.server.ConnectionReceived += ConnectionReceivedCallback;
            await this.server.BindServiceNameAsync("33321");

            var proxy = new INTERNET_PROXY_INFO();
            proxy.dwAccessType = INTERNET_OPEN_TYPE_PROXY;
            proxy.lpszProxy = "http://127.0.0.1:33321";
            proxy.lpszProxyBypass = "";

            var size = Marshal.SizeOf<INTERNET_PROXY_INFO>(proxy);
            var ptr = Marshal.AllocHGlobal(Marshal.SizeOf<INTERNET_PROXY_INFO>(proxy));
            Marshal.StructureToPtr<INTERNET_PROXY_INFO>(proxy, ptr, false);

            var result = NativeMethods.UrlMkSetSessionOption(INTERNET_OPTION_PROXY, ptr, (uint)size, 0);

            Web.Navigate(new Uri("http://web.whatsapp.com/"));
        }

        #region Server
        private StreamSocketListener server;

        async void ConnectionReceivedCallback(StreamSocketListener sender, StreamSocketListenerConnectionReceivedEventArgs args)
        {
            DataReader reader = new DataReader(args.Socket.InputStream);
            reader.InputStreamOptions = InputStreamOptions.Partial;
            uint numStrBytes = await reader.LoadAsync(1024);
            string request = reader.ReadString(numStrBytes);

            using (IOutputStream output = args.Socket.OutputStream)
            {
                string requestMethod = request.Split('\n')[0];
                string[] requestParts = requestMethod.Split(' ');

                if (requestParts[0] == "GET")
                    await SendResponse(requestParts[1], output);
            }
        }

        private async Task SendResponse(string path, IOutputStream os)
        {
            var file = await Package.Current.InstalledLocation.GetFileAsync("Assets\\Default.png");
            var content = await file.OpenStreamForReadAsync();

            using (Stream resp = os.AsStreamForWrite())
            {

                string header = String.Format("HTTP/1.1 200 OK\r\n" +
                    "Content-Length: {0}\r\n" +
                    "Content-Type:  image/png\r\n" +
                    "Connection: close\r\n" +
                    "\r\n",
                    content.Length);
                byte[] headerArray = Encoding.UTF8.GetBytes(header);
                await resp.WriteAsync(headerArray, 0, headerArray.Length);
                await content.CopyToAsync(resp);
            }
        }
        #endregion
    }
}